Tony D

JeffP ran on a dyno early last year, and with the GT35 he was running 8psi and making over 380ft-lbs to the wheels at 4500rpms....engine will turn to 7500rpms. Build the engine to flow first, then size the turbo for the horsepower and spool characteristic you want, and you can easily have a car that will make that kind of horsepower at low boost levels. The response is more linear, and "N/A Like" thought the way the power rushes on as the revs rise seems to be counterintuitive. At these boost levels, exhaust manifold pressure is equal to intake manifold pressure, so it's flowing well through the turbine, minimizing parasitic loss from preturbine backpressure and possible exhaust reversion or decreased cylinder scavenging.

I'd ask 'Did you degree the cam'? I have seen cams that were off several degrees from their cam card specifications. On our Bonneville Car, installing the cam in the '#1' hole had a torque curve that started at 6000 rpms, and went on flat as a table through 8500. Tweaked the cam 2 Degrees, and that same torque curve was now available and present at 4000 rpms! If the difference wasn't so dramatic I would not have remembered...but only a 2 degree adjustment in the cam location relative to where it originally was installed made almost a 2000 rpms difference in useable torque band!!! The top end power did not change one bit...power peak was still at 8250rpm. We ended up running the cam a total of four degrees in each direction from 'straight up' to check the 'best' location. For the $200 we spent on the dyno...I would say it was the best $200 we ever spent in regards to the payoff returned. So if you have the time and money, take it to a dyno and check exatly where your cam produces the most torque and horsepower. If you can, take the time to install either the Arizona Z Car, or Tomei Adjustable Cam Sprocket. Changing the timing on the cam is a SNAP on those compared to the Nissan Motorsports "Multi-Hole Abortion"! After that experience, I started degreeing my cams religiously and that is when I started noticing some cam manufacturer's specs may not be right on to what their cam card says opening events need to be...the profile and the differential between intake and exhaust lobes are pretty much correct, but where that operator starts grinding the cam may float about a bit. So I always now check, and if you are 'loosing power noticably' on the bottom end, you may want to make sure you are optimized for what you have. Now, on to the EFI.... 40mm Triples restrictive, sure, they usually run only 32 or 34mm chokes as well. Same as the Stock Intake Manifold. The EFI is not so much 'junk'---it works really well for what it does, and if you had access to the Bosch (NECS Actually) Setup for the Triple Nissan 45MM ITBS that were in place on the European Rally Cars in the early 70's your thoughts may change about how "junk" they really are... The Megasquirt is really nothing more than the stock box set up so you can EASILY adjust what happens in reagards to inputs and outputs. In the same vein that the stock box is "junk" for a mildly or highly modified system, so would be the Megasquirt be classed "junk" by someone running a full-on Motec controlling variable cam timing, etc etc etc. It's just not what it was designed to do---if something is "junk" because it doesn't work in a misapplied situation....then there is a LOT of "junk" out there: A Geo Metro at a Monster Truck Competition, a 240Z at LeMans entered in the Prototype Division... I won't disagree, the Stock Box is unsuited to the application with the modifications as described but it most definately is not 'junk'--a stock vehicle is very well served by a Stock Box. Let's see how many MS units are around running these vehicles 30 years down the road. Durability and Longevity go a long way towards debunking the "junk" misnomer, IMO. As for spark advance: run as much as you see power gains. Running anything more is useless, and can be argued can be detrimental by putting more heat into the combustion chamber than is required. If you have MS controlling spark, you can play with your bins quite a bit to tailor the timing in each spot...but you have to see on a dyno where you are getting the power and at what point you stop getting a gain in power for more advance being run. There is not a 'magic number' that you need to run---it is all dependent on your power production at each given point. "Don't run more than you need to."

"I'm sure Nissan had fuel economy in mind when they switched to EFI." Actually, the primary concern of Nissan in going to EFI was reduction of Exhaust Emissions. The Japan Specifications for Emissions Control were going to be MUCH stricter than the US in regards to NOx by 1978, and they put the money in early to get something that would easily be tailored to many different markets with a minimum of stocked parts. The harness from a 76 Cal spec car works on a 76 Federal car as well. There is not two different pieces to make and stock spares for...different carburettors for different altitudes, etc... In fact, the EFI system was touted in Japan as the "NAPS" system: Nissan Anti-Pollution System. Starting with the EFI cars, ALL JDM Z's came with Catalysts, whereas EXPORT models didn't necessarily have them! Hell European TURBO models STILL have basic pre-programmed EFI boxes (no ECCS!) without O2 sensors!!! When the S130 came out, in conjuction with the JDM NOx requirements, they ALL got O2 Sensors... My 78 Fairlady 280Z(X) has a "hybrid" EFI system: No cold start injector, Stepper-Motor Idle Speed Control, O2 Sensor, AND Catalyst! VW Beat Nissan in Adoption of the Bosch System. They implemented it in 1968 on their Type III Models, primarily to satiate Emissions Concerns. They held off on the Beetle since it was already established technology, but the Type III was a 'clean slate' vehicle, and designed in the late 50's as a replacement for the Beetle--but it's downfall was a cramped engine bay with dual carburettors (this sound familiar?) so when the emissions rules changed in 67, VW didn't waste any time and got Bosch to make them the first mass-produced EFI system for passenger vehicles. My stock 2+2 runs around 22mpg on a regular highway drive...and I'm not putting around at 55. I probably could get much better if I tweaked the AFM a couple of clicks leaner, and slowed down to 65. I'm in pretty wide open territory and generally when I'm driving the Z on the Weekends traffic is light so I'm in the upper 70mph range + to get that mileage. Then again, with a 3.90 in it...I'm not exactly loafing along at 2500rpms at those speeds either!

I can attest firsthand that Norm's bulid pulls phenomenally. 12 second car built at home without fancy tools and runninng SU's to boot. I feel a kinship with him in that both his car and my wifes 260Z (AKA "The Blue Turd") have similar...er....'patina'! Having supported Turbomachinery in the third world, I can tell you firsthand that 'the proper way to do it' takes a back seat to 'it works' any day. I watched aghast as a guy with a hand grinder took swipes at a Turbine Impeller Stud, and then randomly swiped against pieces in his stock rack until he got a 'spark pattern similar'---nothing like precise metalurgical analysis for 'torque to yield' fastener fabrication! I had gotten into that situation when no less than FOUR OEM-Manufactured pieces failed on pull-up. I was not happy with their OEM machining, as I could see lines in a radius, and it didn't look like it was shot-peened for stress relief. This guy, in his little shop, with his 'benchtop tools' resting on the FLOOR with operators squatting in front of them piled with chips all around...produced a part that looked like it was CHROME. I simply had them 'make it as smooth as you can' and they did. Torqued up, held, and is actually running today at a Refining Location now four years later! Never put too much faith on a 'clean and proper shop'---put more faith in the backlog of work the shop has...if they have a lot of work, there's a reason for it: They probably do a pretty good job! Amazing things can happen with ingenuity and simple hand tools. In the Phillipenes during WW2, they made Colt 1911's using little more than hand labor, chisels, and files! Barrels were drilled using a bit, then broaches for the rifling and final bore were made using broken file pieces woven into bamboo arbors! They didn't place at any International Pistol Shooting Competitions, but they put lead downrange when they needed to! I digress... Side Thought: New Discovery Channel Program for Maching Geeks: Extreme Machining of the Third World! First Edition: Norm squatting on his driveway in the hills of Western N.C. machining his pistons! LOL

I had occasion to use Dry Ice Blasting earlier this year whilst up in Canada (Timmins, in March...) and was pretty impressed by the control it had and the lack of cleanup compared to other methods I have seen employed for the same duty (cleaning electrical winding of large motors in place). They blasted the hell out of everything and the dust was flying---but nothing to cleanup BUT what they dislodged! Media....sublime! LOL

Nice hidden hitch! I used the Fairlady Z Bumper Mounts to make mine, and it's not 'unobtrusive' like yours. Maybe I should re-make mine---that setup would hide behind my bumper!

Do not discount an Inverter in that case. You can get them quite big now, and they will run a lot of stuff. Drill motors, etc... A Small 3-Phase 240V 20A generator should be available from Military Surplus Auctions that is light and will provide what you need. Our ABDR trailers in the USAF (Air Battle Damage Repair) were rolling workshops with stock like you propose, but had a high capacity air compressor for pneumatic tools, as well as a Diesel 10Kw Generator that was used for lighting mostly, though some electrical tools were run off it at times. What you need to figure out is your peak electrical user: Mill or Lathe. From that point you size your generator accordingly. Don't forget floodlights and lighting in the tent!!! Chances are if you run even a 6HP electrical Compressor, that is only 7Amps 240 Single Phase, which is easily accomplished with most of the small commercial generators out there. Chances are good that outside of lighting you will not be running more than one high-load electrical device at the same time...especially if you are a one-man show! That is why most places use gas powered compressors and welders, and then a much smaller electrical generator. For the compressor, I have seen more than one application that made a direct-drive adapter for a hydrostatic motor, and you simply drove the compressor off either the Transmission PTO, or a power-steering pump/hydrostatic pump off the truck's engine. Making your own generator is pretty drastic when you think about voltage regulation and speed governing. The VW did have governors available, and if you were to belt-drive a PTO style Generator it would drive a fairly sizeable unit---if you got the right one, it could be a Generator/Welder! A Lincoln Bobcat was what my pal used in his Portable Welding Business. It did everything, ran his chop saws, welded everything, and ran some lights if he needed it to.... Took up no more than 1/4 of the full size bed on his truck. I still have my eye on it...one day he will sell! LOL

I'm in the Monzster and katman camp (with far less finesse, and more "Primitive Pete Tech"): Made a mandrel out of a chunk of steel, slightly tapered it like the end of a spike, then heated up Sch10 Piping and rammed it onto the mandrel while red hot. That kept falling out of the vice, so I welded it to a stake, and put it in the anvil. Then it was like any other blacksmithing operation: Ram it on, heat it, hammer it....one end ended up nicely matching the ports, the other was easily welded to round tubing. After making Six like that, the obvious conclusion that #3 & 4 were different dawned on me. Having the header flange nearby would probably have caught me before getting that far! All I can say is "Think Ahead"! LOL

Aeromotive Regulator. Disassemble, clean, reassemble, monitor. They have a reputation of drifting with swarf, cleaning usually stops the issue. Make sure testing of pressure is done in similar conditions each time, just to rule out environmental differences. Might be pump, but I'd check reg first.

I haven't forgotten Paul! LOL I just haven't put a big priority on finding those receipts. maybe tomorrow after Jury Duty... I'll get them to you. What ever happened to the Flushseal Plugs? Did those taps and plugs work out for you? What you might want to try is the Graphite Composite Turbo Exhaust Manifold Gasket. It has "octagon" style ports on the exhaust, but will work on either the Square Port or Round Port Heads equally well. And due to the graphite nature of the gasket, it slips and allows the manifolds to expand and contract as needed during warmup and cooldown---while sealing well all the while. Due to it having a metal reinforcement in the layers of graphite, it is very blowout proof, and can also be an absolute BEAR to trim to oversized ports.

Yeah, using compressed gasses that have a tendency to explode in the manifold may have sufficient force to overcome turbine inertia well above idle speed! I someplace have nice photos of an impeller that actually had the blades bend backwards enough to score the root of the next closest impeller valley ... before shelling out completely, breaking off, and migrating to the diffuser portion of the scroll, and parts downstream. "Violent Surge" didn't begin to explain it...until the owner admitted he drove into a puddle and immersed the turbine inlet under boost from a stuck throttle. Turbo didn't like to pump water. Oh, that explained it! LOL

Typically it will be from the Thermostat Housing, and returned to the pump inlet... In this situation it will act as a cold startup bypass line, speeding warmup in cold weather. After shutdown there will also be somewhat of a thermal siphon through the hot side of the head, back to the cooler inlet side of the pump. If you return directly to the radiator, you may (depending on line size) experience some longer warmup times due to the engine having to warm the whole system (or even the radiator) as well as the block when starting cold. What you want is maximum differential pressure during operation. This is afforded by the standard Thermostat Housing, Pump Inlet Scenario. That keeps the turbo cool. Though taking the water source from the bottom of the block, and routing it back to the pump inlet would result in MUCH cooler water being supplied to the turbo, with all the advantages of the Thermostat Outlet...though thermal siphon may not work as well from that location. I'd feel comfortable taking water source from either place (Thermo or block) and returning to the pump inlet for turbo cooling.

Remember the Chrysler "Lean Burn" engines of the 70's and early 80's before EFI? Some cases they were 17 and 18:1.... Iron Block, Iron Heads, hardened seats... Industrial Stationary engines routinely run 22:1 with stochiometric precombustion chambers for consistent ignition. Stellite is your friend in those engines. Stellite Valve Seats, and Valve Faces. Anybody up for recutting a head to optimize lean burn abilities? You got my attention.

I think the discussion was about selling options on parts someone said they had, but didn't in all actuality posess. But what does that have to do with a photograph of flanges that are available for sale (obviously so, since there is a photograph of them)? I'm missing that connection, if there is one at all. I'm waiting to see what the "protest" with the SCTA holds for the Bonneville Car, I may be making my own manifold with Turbo Usages much earlier than I had anticipated. So this thread interests me on that level.

Yep, Float Valve is stuck down, or not sealing. My 77 Impala would do that after a long run...would pump out of the vent in the center of the carb---would have to jump out and bang on the body to get the float to seat the valve. Bad thing was it was doing thin in 1979... So 30+ year old SU's are forgiven! LOL Weigh those floats, make sure they aren't leaking and filling with fuel, causing them to sink. My friend recently replaced two of his floats, as it had failed all around the solder joint at the center of the float. You can boil the floats (brass ones) in hot water....if you see bubbles coming out of the float, you know you got a leak! Sometimes you can solder over the hole you see (do it while it's hot, so the solder will be 'sucked in' as it cools, instead of having air blowing out as you heat the float to solder it!) but you have to be careful not to make the float too heavy, or the bouyancy is affected, and you end up in the same situation you were in with the leak! Good Luck!

Summing up what we teach our Technicians: Surge is the phenomenon of compressor flowpath instantaneously reversing due to the inability of the compressor to continue making pressure at that given flowpoint. Air delaminates from the blades, slips backwards until pressure comes to a point where stable flow in the normal direction can again occur, and then it will repeat. From there, there are other terms that are used, like 'pumping' whereby the compressor operates in a surge condition continuously. Bad! Microsurging can occur when ambient conditions make the flows or densities marginal for the conditions...you can not hear it in many cases unless you mic up the compressor housing ultrasonically. I digress... "Backspin" or "Pinwheeling" is the phenomenon whereby the turbine is actually driven backward from an air source that has sufficient volume to drive it for a time. This would be very unlikely in a vehicular installation if there was any kind of BOV in the system...mainly because even on lift-throttle the turbine is still getting energy to spin in the correct direction, and that would have to be ovecome as well. In industrial compressors, I have seen failed discharge check valves cause Pinwheeling. But not while the unit is coasting down. It happens after the inertia of the drive is stopped, and then the motive force of stored compressed air starts driving the wheels of the compressor backwards like Turbine Drives...Failure happens almost immediately as the bearings are directional, and speeds come up so fast things just go bad, very bad...quickly.

This is concurrent with what my understanding of several items I have checked upon as well. When spin-testing Turbomachinery Impellers, the dimensional integrity is not determined, it's more of a 'spin to fail' or 'overspeed' mode of testing. As long as what they are checking for passes their criteria, they get their certification. This is not to say they are making something useless, this sounds more like a bore tolerance mistake---and those things happen. If they make it good, by either reworking it or replacing it with one of dimensionally accurate machining---then it's all good. The SFI rating regarding Structural Integrity is important to me---Clutches, Flywheels, etc.... Same for a Damper---you don't need a chunk of something flying off doing impromptu bodywork (either vehicular, or personal!) during a run! Tolerances are always subject to buggering it up. They need to make it good, and I'd say the SFI rating is a 'good insurance' for any part put on the car, and is---as Dragonfly says, not related at all to how it is supposed to fit. Myself, I may have been tempted to have it finish-ground slighty undersized as I mentioned above. The impellers I work with can have as much as 0.003+" Interference on a 1.5" shaft! Freeze the Shaft, Heat the impeller in a 600F oven, and hope it all goes together without cocking and binding halfway down. Believe it or not, those parts DO come apart when it's time for overhaul as well. It just takes...er....'effort'! LOL

Don't get greedy, the VW industrial engines were only rated about 25hp. They were interchangable with Wisconsin MV4HD engines in Military Support Equipment....the Japanese used VW Industrial Engines in their support stuff for the F15, where we used Wisconsins...and later Diesels. The A-Series Nissan Engines were also rated similarly, and give good service life. When you get above about 30HP, TurboDiesels rule in things like Small Tractors and Bobcats---generators as well if you want a small package.

I watch this closely, thanks for the pioneering, guys. I'll need a better ratio for Bonneville, and was thinking of harvesting an Armada Unit as well for those tasty gears!

Actually, Motorsport Division at Nissan recomended Locktite Green for Damper Bores to make sure there was not any chance of fretting or working the keyway in competition engines. If you have a turbo engine that you rev to higher revs regularly, I'd be more comfortable with a tight damper that I had to heat to install (along with loctite) than a stock slip fit. Granted, given the interference fit that was measured in this case, that is dead wrong. But 3 to 8 tenths of a thousandth is acceptable for a 'tight fit' and in some cases even more can be had and easily assembled with slight heating as noted by Dragonfly. What it came like 'stock' has little to do with it, if you want something that won't rattle around, 'tight' is better then 'line to line'...

PM ME I'm heading over to Los Alamitos this evening for rewiring on the Bonneville Car...for the hassle of shipping it, I can pick it up anywhere in the LA Basin. I'll be working in Torrance next week as well.

"I was hesitant to open up the Quaife, because they don't break and the warranty card says I shouldn't, but I decided to because there hasn't been a picture thread comparing the 2 side by side." I will bet money, if you reveal the comparison you did, and supply them with the photos....they will 1) Understand 2) Pay you something for the rights to use them as 'examples' when fielding inquiries! Thanks for a very informative post, and I nominate for "Sticky" as well so people can see for themselves and make the decision based on what they decide they need, or if they actually want to take the time to rebuild new parts so they know they will work...

That is Fred Sangalang's Car...his project shown at this years' MSA was a mid-engined 240Z that utilized the new Maxima Drivetrain mounted behind the seats...and it had an onboard jacking system so you could rotate the car about it's centerpoint. Really handy if you get into a deadend road and can't three-point....I guess....LOL As for what parts are what on one of Fred's cars...anybody's guess! It may have started as one thing, but he will rework just about anything to make it fit. Photos above a great case in point! Should have seen his '4WDZ' that was mounted on a Bronco 2 Frame! That started out as an innocent comment one day of "Hey Fred, now the only thing you haven't done was make a 4 By 4 Z-Car!" You gotta watch what you say around him...he WILL make it work! LOL He will also, if you ask him, tell you exactly what he did in detail on whatever you want to know. Really a great craftsman, who is proud of his work, and more than willing to share what he did to overcome whatever challenge was presented. He is a great guy to talk to at a car show about his car---really nice! If you get the chance at an MSA show, or anywhere else, just ask him, he'll tell you.

The XS Manifold clearly states it's for an RB20 / RB25, with differentiations on what is different between the two applications. I bought one of their T3/T3 External Wastegate Adapter Flanges...just because. One day I might use it...or not. For the price....who cares? LOL

Better to do a pin to pin check from the connection at the MS, and then at any juncture heading back to the sensor, culminating with a sensor resistance check. If you get a noticable drop in resistance as you work toward the sensor, the connection you just eliminated is your problem. It's not uncommon for resistance to build up in connections, and cause false readings. Skews them high or low, depending. Unless they are both drawing from the same sensor, likely they will be different---but not that different! Somewhere you should be able to dig up a resistance-to-temperature curve for the sensors. That will tell you the range you should expect to see during your troubleshooting. Many times people skip to sensor, when it's a harness connection that is the problem. Doing the pin to pin checks the whole loop first, and then you eliminate pieces as you go towards the sensor. Good Luck.