technicalninja

Yes, stock rods and the crank are forged. In 20 years of working as an Import car tech I cannot remember last time I found cast rods or crank in any Import-Japanese or European. Air cooled VWs had cast stuff.

Cold adjustment works fine, will get it within .001 of hot setting. I normally adjust valves first time cold then after running engine for a few days recheck it hot. Sometimes its perfect hot,it is never far off. valve adjustment is more critical for radical cams and should be done to cam makers specs.

Early 5 speeds have a problem with main shaft lock nuts loosening up, comingoff and allowing the 5th gear to "walk" up and down the shaft. Nissan first changed the threads to left hand then added roll pin for the 5th gear thrust plate (originally had small ball bearing to locate thrust plate). Often times a early 5 speed with this problem will have this small ball bearing stuck to the drain plug magnet when you pull tranny drain plug. I have been able to fix some of the trannys that had this problem I've seen but usually it is cheaper to get a junkyard tranny. Get as late a tranny as you can as the late 82 and all 83 5spds seem to have both upgrades to the mainshaft. The left handed threads tend to tighten as the tranny is used instead of loosen. All versions have the lock nut "peened" into the mainshaft but the change of thrust that this part sees rocks the nut back and forth and removes the peening after time. Increasing power out put of engine causes this to happen sooner. My technique of refitting old style main nut is to use new Nissan nut, torque to high end of range, and peen the nut to the shaft as deep as I can go. Use red lock tight also. Ive never had to take one off after doing this but I feel sorry for the guy that does. This may have nothing to do with your problem. If you cannot find problem with clutch or mounts (check rear end mount also) then take back case off of trans and check play of 5th gear. Grab last gear on main shaft and try to move it back and forth. It should not move more that .004". Ive seen some where gear had been moving back and forth on shaft 1.5 to 2 inches which destroyed gear and shaft. This tranny had strange clunk noises when engaging 5th (more noticable under hard shifts). Good luck Rick

Depends on type of compressor bypass valve(CBV). If the valve is open anytime a vacuum (non-boost) conditions exist behind throttle plate then some benefits can be had. When the car is driven below boost threshold the bypass system is open which can improve throttle response (shorter intake tract) and more importantly the air charge is not passing through the turbo. This has two benefits- less heat in air charge and the turbo spins slightly faster as fewer air molecules are passing through it thus allowing earlier boost threshold. This will always be a small improvement not a major one and requires extra piping between CBV and intake tract. Some CBVs, especially "blow off valves" only vent when boost has already been produced and then a vacuum condition has been sensed by the valve. This style of valve does not allow the non boost bypass to occur during normal cruise and the above mentioned gains will not occur. Recirculating from one of these valves would help by allowing pressure difference across turbo to equalize quicker (reducing pressure on discharge side while increasing pressure on intake side) thus making it "faster" at reducing compressor surge. Secondly it would create a higher pressure on intake side during fast shifts and would allow the turbo to come on slightly quicker. This is not very noticable as during this style of driving the turbo normally is very quick at regaining boost (6000 rpm shift from 2nd to 3rd at full throttle boost comes back really fast with out any bypass valve at all). It is not mandatory to have an intercooler to use a recirculating bypass valve. The air charge will never go through turbo more than twice and as it is allowed to depressurize it reduces in tempature (not back to ambient but not a full boost temp either). as it is the first air repressurized it suffers less reheating than it got the first time through the turbo. Its already at a higher pressure than ambient and the turbo does take a little time to reach full boost so it escapes the large pres/temp rise it got the first time. The open (any time vacuum is present) bypass valve has all of the gains of the "blow off style" valve and the gains from the first paragraph also. It is the way to IMO. It can make noise at both boost on-set and at throttle close/normal blow off. The boost on-set noise can be strange and disquieting if you don't know about it (sort of a sucking-popping noise) and is much quiter than at blow-off. The blow-off noise is lower that a normal open blow off and if you like the PSSST sound this set up is not for you. Basically open compressor bypass valve= faster surge control, better off boost throttle response, increased compressor response (both full throttle and cruise operation), more complexity, and quieter operation. The gains are minor but real. They are most noticable going from cruise to boost (hiway passing type manuver). A compressor bypass valve (any style) is almost mandatory on a blow through carb set up or you can get a massive rich condition at throttle close. Hope this answers your question Rick

Dirt simple. After clutch job finished (tranny helps support engine) remove pan. You do not have to disco engine mounts. after pan loose from block turn crank from front pully until pan can be removed towards tranny. Remove oil pump pick up (2 8X1.25 bolts) loosen all main bolts except last journal 1 turn only (last journal is very difficult to remove in car- I would leave alone) remove main caps one at a time (lossen bolts and use bolts to wiggle cap untill it releases from block) Replace bearing in cap. look at exposed crank main journal. The ends of the upper bearing will be exposed- one side will have a locating tab which fits into block. push other side of bearing up and bearing will rotate on crank allowing replacement. install in reverse order being carefull that locating tab fits into recess in bearing journal and bearing shell is not angled in block. Lube crank side of bearing with a little lubri-plate or eng assembly lube. reinstall lower cap and hand tighten main cap bolts evenly. finish one journal before moving to next. The center journal (and the rear more so) have larger shoulders where they fit into block. Nissan machined removal holes into both of thes journals. Thread a 8X1.25 bolt into hole and use a small prybar (large screwdriver) to remove (once again wiggle cap- do not try to remove in one single pry). Slipping center main in is tighter but can be done. Make sure you replace bearings with identical ones as top and bottom are different and widths change with journal (center journal is obvious as it has thrust built on) first and last journal are slightly wider that the rest, block inserts have oil groove in them, cap inserts do not. This may vary with manufactors. Total cost for all parts could be below 50 dollars and although this is not a "correct" repair it could get you many miles down the road. It would take me an afternoon to replace bearings and can easily be done on jack stands. If I went to all of the trouble to remove engine I would do a correct job and have crank checked by machine shop and complete lower end rebuid as nec. Very expensive and time consuming. Final note- use a good torque wrench to torque all main bearing bolts. Hope this helps. Good luck

Saw a picture of a 76 that got slideways and hit a pole at about 45 mph. Took the hit 6 inches aft of passenger door forward edge. Crushed body all the way into transmission tunnel. If a passenger had been present legs would have been totally crushed and they would have been lucky to live. Driver was not hurt and walked away. A cage would have helped alot and will give nice stiffening gains. I don't think a 6 point would have helped. Lucky driver!

40 teeth on upper gear=9 degrees cam rotation or 18 degrees crank rotation. Stock gears have 3 holes with #2 4 degrees advanced of #1 and #3 4 degrees advanced of #2. I have bored out holes and used G.M. cam locator eccentrics. (Super Shops/Summit) to allow adjustability. I have also used the HKS multihole unit. I have seen almost no improvements over the stock gear and believe that the adjustable pully is only needed on extremely prepared motors (high compression and cam over .500 lift). After carefully "dialing in" the cam I've ended up trying the other possible holes and often ended up in a different hole than I dialed in. Waste of time and effort. My suggestion- Use stock gear, try the 3 holes, and see which one works better for you. Save your money and buy some other performance item for the car. If using an aftermarket cam check valve to piston clearance in all three holes as cam timing adjustment does effect clearance. On an extreme engine the multihole (8 or 9) gear may help with cam to piston clearance by allowing finer adjustments. Yes, finely adjustable cam timing is a good thing but most street engines do not need this feature. What is your engine build up? How wild are you going? Hope this helps Rick

I've been using my VW/Porsche tool for years on L-series- Works great. As it will only contact flywheel at 1 point be sure to TIGHTEN the bolt you attach it with to lock it in place. My tool has two sides to it (long teeth and short teeth) I use long teeth side. Be sure to lock it so the contact tooth is on the feed side of the lock bolt (as you come to torque the rotation helps to lock the tool- sort of like channel locks).

One of the nicest aspects of a stand alone F.I. system is that with software changes it can adapt to the Z owners whims. While the "big" engine is being built you can use a "mule" stocker motor and the injection will work fine. If you change your plans you do not have to purchase new fuel delivery equiptment. I would use an early 280Z manifold, properly sized injectors (many good choices exist both new and used), and a 60mm throttle body (aftermarket or KA engine type). Many choices exist for aftermarket F.I. systems. Whole threads exist on this site which debate the different brands. Good pieces are available used. Carbs can and will continue to power high horsepower engines but they have to be matched closely to their application. Some carb designs allow the owner to change the basic flow capabilities of the carburator (Weber DCOE, Mikuni PHH, Solex) but require additional parts to make these changes Basic 3X2 Weber choke change= 6 chokes@$20, 6 mains@$4, 6 airs@$3=$162 per major flow change. The cost for the same change with the F.I. is some laptop time (both of these changes assume that labor costs are not a factor). The F.I. can be harder to understand but once learned it is easier to work with than carbs and has proven dependable. F.I. can support a 500 HP L series turbo. I do not believe that carbs can.

The "stub shafts" that slide into the diff are identical between R200 diffs installed in 75-89 Zs and ZXs with the exception being the hypoid limited slip of 88. You can use any of the halfshafts or flanges if you want. They meerly "pop" into the diff and are held in with circlips. I prefer the late Z31 turbo axles that match the LSD just because they appear most "robust". For the original poster- I would not reuse the 240 stuff- try to get any CV based axles. The hypoid limited slip of 88 is its own animal-requires it's correct axle. I have seen some posts about using other axles with it but none have seemed definite in what fits. Any hypoid users care to add to this?

Stock Z injector (na) duty cycle is about 80 percent. The CTS mod can add additional fuel up to probably 95 percent duty cycle. This is a gain of 12+ percent total and will support mild to moderate standard displacement L28 engine mods. An adjustable FPR can support much much more(as long as the fuel pump can supply). The CTS mod is a super cheap tuning tool that can increase fuel supply a little. It will NOT be the answer to increasing fuel in a turbo situation where a FPR/RRFPR would help far better. The cost of the CTS mod can't be beat although. Most coolant temp sensors work the same way. As temps heat up resistance across the 2 sensor leads DECREASE. The F.I. units vary the base fuel curve by what resistance the sensor is at. Curve has no settings;adjusts to any changes to resistance (no hot and cold maps-One base map varied by multiple inputs). Inputs in order of their ability to adjust base map (most changing first)-RPM signal from ignition, AFM, CTS, TPS,O2,ATS (air temp),baro(if equipt). RPM is not normally trickable. AFM range is maxed at WOT by stock engine,CTS is first easily tricked sensor circuit. TPS can also be used but early Zs (pre 300ZX) have a tps with three positions (wot,closed,and anything in between)not very selective but WOT can be adjusted to turn on earlier in throttle range. Might give tiny midrange increase. The O2 sensor and baro sensor have such small impact on fuel curves they are not usually a good place to try. Exceptions ALWAYS exist to ANY rule. Either type of CTS sensor works on same principles and the mod is applicable to either. WOT releases most EFI systems from "closed loop mode" and effectivley turns off signal from O2 sensor but all other signals still adjust fuel injector duty cycle. To verify just disconnect CTS(car thinks it -127 degrees) and try to drive car at WOT-may not run-WAY WAY rich-especially at all but redline. Then cross to leads in sensor harness (car thinks its 500 degrees) and try to rerun-may not run-WAY WAY lean. Hope this helps Rick

Check thread "afm adjustment for more fuel" under fuel delivery. I typed up a modification I have used on non-turbo mild-medium modified motors. This technique will work on turbo cars as well but only for very mild increases in fuel delivery.(fine tuning an AFR). It will not fix your problem. Your car sounds like it was getting sick just before you had an intercooler installed. I don't think the intercooler has anything to do with it but you should be able to remove the tubes attached to engine, reinstall J pipe and eliminate the intercooler for testing purposes. Are you sure that car is lean after warm start? if you had one or more injectors leaking down after car is shut off it could be flooding engine. A way to test- precondition car so it will do its trick, as car is started have someone administer a small amount of carb spray(B12 works best as a fuel) in to a vacuum line (fuel pressure regulator line works good) and see if the car starts and accelerates easier. If it runs easier the your are lean,if it doesn't help or hurts then your rich. Disconnecting fuel pressure regulator vacuum port will make a F.I. run richer during light load operation. Look for fuel in regulator vac line,if found replace regulator. Your description of symptoms sounds most like a bad AFM. Has anyone checked for plate binding at closed position (has to be checked with AFM mounted in car at normal riding position). Getting an extra AFM or borrowing one is not out of the question. Another useful test is the shut down fuel pressure test. When engine is turned off notice fuel pressure(24-28 lbs common). leave car for an hour did fuel pressure drop drastically? A small drop, 2-4 PSI< is expected. A drop to 0 means something in the fuel supply/distribution system is leaking- Common culprit is check valve in fuel pump. Represurise fuel system (crank car untill gauge shows pressure-a good pump will presurise in 1-3 seconds) with car off carefully clamp off fuel inlet line(near filter) with a pair if visegrips. You do not want to clamp too tight-can damage line but you want it tight enough to seal line off. Watch for fuel pressure drop-if still large further testing will be necessary. I have many times removed the injection lines and injectors as a complete set leaving lines attached to find leaking injectors and check injector patterns. Provide power to fuel pump-look for leaks. injectors should not leak at all. Another common issue with air flow controlled F.I. is the integrity of the intake tract. Zs used many flexible rubber tubes with "pleated areas" that get cracks down in the pleats which can be hard to find. The most recent work may have dislodged a hose or made a crack worse. All air which goes in the engine must go through the AFM or incorrect mixtures will result. Common problem occures on F.I. Zs. clutch install causes symptoms like yours. What had happened is engine angle changed when trans was taken off-pulled hose off of AFM. After clutch install complete engine partially reinstalled hose (flush on top-kinked on bottom). Car now has a seriously bad drivabilty problem and from all apperances nothing changed. Customer now thinks mechanic is idiot. Mechanic may be very good- just hasn't seen that particular trick before. Your mechanic is right about no AFR adjustment on stock parts. Nissan and other manufactors do not want normal consumers to alter their settings. I am sure that the cars could never be EPA certified if they were adjustable. Carb mixture adjustment anti-tamper caps have been around for 30 years. Abnormal consumers (me and others like me) can usually find a way to adjust AFR. If a shop modifies an emission control device for profit the crime is a felony punishable by up to 5years Federal and/or $100,000 dollar fine. When asked if I would "gut a cat" I price it at $250,000- have had no takers yet! Most shops which do such thing get away with it but if I'm going to commit what the US goverment thinks is a felony I want to make a lot of money! Typing about modifications is not illegal. If I modify my own car it is a misdemeanor with a minor fine The only factory adjustment is AFM bypass screw which only affects idle AFR. the CTS sensor is cheap-can be tested with info found in Nissan factory manual. I have found many bad ones. also check wiring connection for corrosion. Hope this gives you some testing hints. good luck!

Who here has used nitrous on their turbo L28s? What were your results? Did you have any failures, problems? Anybody have opinions? Search is still not working (no matches for nitrous- tried "intercooler" just to check the search function, got only 10 matches). .

I am building a 2005 challenge car now. I will post the project as it is built. 73 240Z-details later.

I did it by "seat of pants". The engine was originally just slapped together. .30over L28 flat top (incredibly strange-all other overbores I have seen were .20 or .40-could not buy replacement rings-no supply) . I reused all original bearing, rings, etc. N47 non-prepared cylinder head. Basically cleaned and regasketed everything- spent like $100. With the stock cam the engine pinged badly on 93 octane. I did the fuel mod and added resistance untill I lost my detonation then did some plug checking runs. No one ever talks about reading plugs anymore! it actually works pretty good as long as you seen plugs from lean,correct,and rich motors before. Plug check method- Car should be fully warmed up before completing this test.Drive car "briskly" and have the last part of your run a 2+min high engine speed/mid throttle run (usually 2nd and 3rd gear-on freeway 3500-5000 rpm. Pull plugs and inspect 15 seconds after you turn car off-don't idle car for any time after run. It is important to have already applied antisieze to plugs and have the plugs installed lightly in the head(keeps from destroying cyl head). Look at insulator of plug- Rich will apear brown to black and some times its even sooty, Correct will look slightly off white (kitchen appliance white- almond). Lean will be extremly white and may appear shiny or glazed,sometimes with little specks on the insulator-obviously has been HOT. I removed a set once that appeared to be glowing white and watched as the "glow" faded out of the plugs in about two minutes. This is why I pull plugs immediatley to check and do not idle car for longer than nec. The "color" of the plugs changes (probably just a little) with time. After getting nice off-white plugs in sport mode I then drove car at normal freeway settings and rechecked plugs still were same color. I could vary the plug color with the pot by the time I was finished (ended up getting a feel for how much 1 turn was worth on the pot). I have since had the car inspected and the inspection showed 13.7:1. I do not believe the inspection procedure accurately mimics the road(especialy my driving habits) but the numbers were closer to stoich than I expected. One note- The stock cam in this engine produced compression values (Snap-On comp gauge) between 240 and 250 PSI. Adding a performance cam dropped readings to 175-185 and seems to have solved any detonation issues. The stock cam had tremendous low end power but was going away by 5800 rpm. New cam is much better on top end(still has decent low end). Original cam could leave stop sign in 4th with out lugging the engine(won a bet with this cam 0-100 without shifting or clutch slippage $20). Fuel injection was well dialed in. I guess I spent 5 or 6 hours over 2 weeks playing with settings. I had it very close by the second hour although. I do have 20+years experience as a professional import car tech and and knew what I was doing. I would think a someone who has never done anything like this would take twice as long playing around with it before they mastered it. The new cam required a minor fuel add (plugs got a white again). Have not retested it since. Still haven't gotten out to look at potentiometer-life to busy. Hope this helps Rick

Need to go look at my car, cold and dark out there now. I did it years ago and cannot remember. What is range on your pot, it should be 1-1000ohms. 15 ohms per turn doesn't sound correct- more like 100 per turn on mine. I will look at car tomarrow and repost but you should be able to figure it out with a DVOM - Put it on 2k Ohms scale- attach leads to two of the little post-see if meter reading changes as you turn screw. Change leads around untill you find the adjustable set. 1 of the post is usually a reference and will not be used in this application. It is also possible to just use a normal resistor ( I would start with a 300 ohm one) but is not adjustable.

What material did you use to make your "molds". Is it available to mere mortals-where can it be purchased. Very nice. The difference between as cast and 80 grit is suprising- I saw the pictures before your last post and thought "boy it looks like he overpolished the intake"-many head porters leave intakes between 80 and 120 to improve laminar flow. 80 grit mold surface came out much smoother than I would have thought. Keep us informed of your progress. Threads like this one are the reason HybridZ is IMO the best Z Car technical site.

The wires from the distributor go into the wiring harness- Sorry I couldn't resist! actually they go all the way to the 300ZXs brain which controls the ignition also. My 1986 Nissan 300ZX service manuel shows the following BW (black with white stripe) is shared system voltage(switched battery) and goes to the brain on pin 35. It also powers AAC valve,EGR solenoid,idle up solenoid, and air mass sensor B (black) does not go to brain- it is just a ground connection GB (green with black stripe) signal out to brain pin 17 GY (green with yellow stripe) signal out to brain pin 8 A shield system exists inside wiring harness(basically a conductive sleave around all 4 wires which is connected to a seperate ground- reduces interferance from other EMI sources IE secondary ignition wires) The two signal wires will have different rates of change on them. One will make 6 "signals" for 1 complete distributor rotation(2 complete engine rotations) and 1 of the signals will be longer then the others (marks cylinder #1) The other wire will have 360 signals per complete distributor rotation. I don't know which one is which. The Nissan manuels diagnostic procedures check for power at BW, ground at B with ignition switch in on position and at connector disconnected from dist, continuity when you cross GB and GY at connector and infinite resistance between the wires when the dist is pluged in (readings take from ECCS pins for these two wires). If this doesn't fix the problem Nissan suggest replacing the dist (let's throw parts at the car, maybe it will fix it!). Both signal wires can be tested with a wave pattern DVOM or a scope. Many stand alone systems expect a signal at each cylinders TDC and a single seperate signal to mark cyl 1. Most probably won't work with 2 degree signal that the 300zx dist puts out. It might be possible to change the outer rings signal (the 360 slit ring set) by blocking off 359 or cutting out the ring and spokes but leaving 1 'spoke" intact to provide the #1 signal. Try blocking holes first. Maybe you system can detect the longer 1 of the 6 and all this is not applicable. Look at the wires beyond the first connector- harness side to apply this info for your dist. Often Nissan (and others) do not continue the correct color code in short harnesses connected to componets. The factory manuel does show where these wires fit into the oval shaped connector-page EF&EC 50-51. Guess I'm not with it- what does STANKONIA mean-just leave out any unpostabe words. Hope this helps

K-Jetronic is CIS. In its most recent forms its appearance is very similar to the L-Jetronic (electronic pulsed injection) but it still is vastly different animal. Much info exists on its modification and tuning throughout the Internet. Now about your wish for a 911. Z food normally is comprised of Camero, Mustang, Vett, and Honda but a nice fat 911 is a tasty treat every now and then. I just love the look on their face when the "Old Raty Z" screams by. Newer 911s are not to be messed with (YET). Having owned both makes I can honestly say the I will always have a Z and I may never own another P-Wagen. Parts are drastically!!! expensive and the cars are harder to work on than the Zs. Not much faster than a z in stock form the 911 also has an interesting added entertainment feature- Trailing Throttle Oversteer. Gauranteed to terrify both the passenger and the driver for years to come. Back to the post- Z-Ya,I have three suggestions which you may already be doing 60 MM throttle body, either aftermarket or Nissan KE motor(240SX,Stanza Cold air system (Motorsport style- Building it your self would not be hard) Good header/manifold 2.5 inch exhaust. Motorsports is cheap and fits pretty good. Just suggestions but they "bring out the" motor and are not very expensive

Most 911s had a type of F.I. called CIS (constant injection system) this "bugspray" F.I. works on totally different prinicples but it can be "Played" with to, just the above modifications are not applicable. I neglected to advise how to find the "return" wiring from the CTS. The CTS has two wires going to it. Unplug harness from sensor under thermostat cover, turn ignition to "on" one wire will have a 5 volt reference voltage applied to it, that wire is what I call sensor feed. The other wire is the one you want to splice into and you can put potentiometer in engine compartment but it is a cleaner install and easier to adjust in interior. Potentiometer will actually work in either wire but a basic rule is to make your modifications AFTER the sensor. Reduces strange F.I. issues. Old shop technicain slang for 911 is "Super Chicken" for the SC desigination on most of them-just don't let your customer hear you refer to his car this way- they don't understand! get bent outa shape.

Might want to check that fire extinguisher, appears to be discharged! Quick-someone get the marshmellows!

R200 3.54 4 or 5 spped cars R180 3.54 automatics R200s can take a lot of abuse but 1/2 shafts are the weak link. Spicer 5-1505X U-joints are an upgrade. RossC (ModernMotorsports) has good adaptors for 280zx/300zx CV halfshafts- This appears to be the strongest setup. R180 is OK for mild use. Make sure the tranny you use has an overdrive (700R4-T5-T56) or highway cruise will be annoying.

Bad idea! No airfilter on your new/expensive turbo/engine is a sure way to have to purchase more parts and picking up HOT air from engine compartment doesn't make power either. I 've seen such airhorns pick up a bird- most nasty! did not hurt engine but very gross-luckly car was not intercooled or would it have been worse. Make a good cold air system,you will be happier.

Changing the spring tension can be used to "tune" the F.I. but at the stock 280 Z engines max flow rates it is almost fully open anyways and cannot be considered as a good method to increase total fuel delivery. I have your basic engine in my 78 280Z 10.5:1(flat top/N42) medium cam and I increased my total fuel delivery by placing a variable ratio potentiometer in the return wire from the coolant temp sensor. This critter is basically a variable resistor with a range of 0-1000 ohms and was dirt cheap at Radio Shack (.99). You have to determine your return wire from the CTS and splice the unit in (Unit has two posts- cut CTS return wire and apply unit in series). I cut CTS wiring near brain and added 2 wire speaker wire up along dash, tucked it behind A pillar trim and left the end at top of trim panel. Soldered unit to wires, soldered wires to cut wires. The unit is a small blue box with a small common headed screw coming out of it and is un-noticeable at top of trim panel. Adding resistance to this circuit basically tricks the brain into thinking the engine is cooler than it is and this lengthens the injector open time thus delivering more fuel. Through trial and error I found 350 ohms to be the setting my car runs best on. I can vary the AFR easily with a tiny screwdriver. After finding the best full throttle point I then vary the AFM spring setting to retune my midrange. Adjusting the AFM- First carefully cut the silicon seal that holds the black plastic cover on the AFM. The spring tension is adjusted by loosening the bolt which locates the black plastic spring carrier, rotating the carrier, and retightening bolt. It is a good idea to mark the original location by scribing a line in the black plastic carrier adjacent to the bolt before adjustment. You do not have to loosen the bolt very much to be able to re-index the carrier. The carrier has teeth around the outer perimeter which mesh with the locater tab held down by the bolt. Make sure that the teeth mesh with the locater tab or you can break the carrier when you tighten the bolt down. The original location has spring tension against it. When you loosen it it will try to release the tension by rotating so hold on to the carrier when you loosen it. Adding tension reduces midrange fuel. Decreasing tension adds fuel. Reduce tension by 5 teeth then drive car. Increase tension by 2 teeth-drive car. Continue tightening by two until you feel a flat spot when flooring car from 3rd gear 3000 rpm cruise. After you find the lean flat spot reduce tension 1 to 2 teeth. You can re-silicon the cover on but I use a fat rubber band to hold mine on. My car ended up (after much messing with) 3 teeth tighter than stock (this is with the above mentioned CTS modification installed). Having a AFR gauge would make this process easier but it can be done with out one. This modification should cost less than 5 dollars and will give a fair amount of adjustability to the stock system. The CTS modification adjusts the basic fuel delivery, The AFM adjustment tunes it in midrange/acceleration. All of the above assumes the stock F.I. is in good shape with proper injector patterns. If you don't know the age/condition of your injectors remove them and send to a shop specializing in F.I. repair. Normally these shops don't work on whole car- you have to bring them the injectors separate. Have the injectors patterns checked/injectors cleaned. All 6 of my original injectors were bad/had poor patterns so I replaced them with Beck/Arnley "rebuilt" injectors. I compared the "new" Beck/Arnley injectors with the "rebuilt" and the was no difference just boxes. I cannot believe that it is cost effective for the manufactor to use my old injectors and the price difference is just a sales gimmick. New were $55 each, "rebuilt" were $30. Hope this helps Rick

Increasing the pressure of any liquid increases its boiling point and will reduce vaporlock issues. This is the reason Nissan added a transfer pump in 72. Fuel at 2 PSI is less likely to vaporlock that fuel at lower than atmospheric pressure IE the 70 and 71 Z which had massive vaporlock problems. Having said that, The tripples that I have worked with have been very sensitive to overpressure issues- Webers will some times puke fuel out of every orifice at 5 PSI; 1.5 PSI over their suggested 3.5PSI. Mikunis seem to be less sensitive. Use a 3.5 to 4 PSI rated pump mounted back by the tank. I prefer the little square Facet style. Most times I don't use any regulator. I will run a pressure gauge taped to the window for a high speed test drive. If it will maintain 2.5 PSI in 3rd gear full throttle redline its good. If it won't I remove and block return line and retest. Worked so far for me. No vaporlock issues on 15+ cars over the last 10 years even here in Texas. Properly heat sheilding/routing of fuel line is important also. Every round cylinder "Carter" style pump I have installed failed at some point and had to be replaced. I have never had to redo a "Facet" style pump Every high capacity/7-15 PSI fuel system has needed serious work to make it work-restrictors,fuel pressure regulators, etc... They have never been worth it. The Facet style pump is very noisy if you bolt it to the unibody. I mount them with a couple of V.W. radiator insulators. Remember to add a ground strap from pump body to car if your pump has only one wire.