Tony D

I will cross pollinate a thread here from another forum and mention to Bastaad that I witnessed JeffP's car on the dyno smoke his CF clutch at.... are you ready for this? "About 4000 rpms" SOUND FAMILIAR? Got a good idea where PEAK TORQUE might be in a turbo Z? If Pallnet built his engine from Nissan parts, and JeffP has a radical cam, and all custom stuff and they both fry the clutch around 4K, you gott a know there is some sort of "characteristic curve" to a turbo Nissan L-Engine. I bet you look at your dyno graph now, and go "Hmmmmmmmm, no shi...."

yes, it is. The torque peak only moves north and south on the dyno sheet, depending on the intake manifold pressure. The curve should be identical for torque, only near the top of the graph as you add more boost. The peak moves east and west depending on variables like camshaft, camshaft timing, possibly ignition timing, and maybe carburettor size... But generally speaking, "peak" torque on a turbo Z will be nearly identical to a stocker, just further north on the graph when you crank in boost. Stock N/A L28 makes peak HP at what? 5.5K or thereabouts? Where do most guys dyno out at with peak HP? 5.5 to 5.8K? Not that big a difference to worry about. But the "flat spot" of the torque curve remains fairly constant. You also have to consider "how much torque do you need to accelerate the way you want" which enters into "performance -vs- economy" argument. Some may want the engine cruising at 4000 rpms so the boost response is instantaneuos, and gives a much harder pull when used. others can wait a bit, and gear so they are around 3000 so response is still instantaneuos, but you may have to pull a bit to really get going... This is BTW the origin of the commonly misused term of "turbo lag"... People confuse what happened in 60's vehicles with improper driving technique. Drive a turbo corvair and you will know what REAL turbo lag is about. The engine made seriously variable boost in each gear. Maxing out around 10psi in fourth around 5500rpm (where it was rated as a magnificiently peaky 180HP!) Caomparing that response to what a turbo ZX does is like night and day!

here: http://www.mcmaster.com put "polycarbonate sheeting" in the search window, and start the search. You should find a 24X48" sheet is around $40 in the .188 thickness---which if I recall is the thickness of the factory glass. These guys are probably not the cheapest place to get it, but they have one of just about EVERYTHING, you will be amazed at what they have in stock and what they offer in the way of anything... The temperature resistance for this stuff is rated at 240 degrees maximum. From what I remember from when I did this last (around 1987) I would heat it to around 300Deg F or 320... I would hook all the heat guns up on a circuit I made from an old oven timer that would simply swith them on and off from an outlet strip I made from a four plug outlet box and some 12 gauge SO4 extension Cord wire and hospital grade three-prong plugs I horked from work... This worked good enough to keep the "oven" temperature fairly constant. When Atlas Copco bought me that Steinel Heat gun from Germany with the digital readout and variable temperature output and display I was thinking "If only I had this then..." Man, just set a single gun to 320, and walk away. Come back and check in an hour or so, and if it's ready, Pick and droop. Another way to do this if you don'twant to droop the glass over another piece of glass is to lay your glass "outside down" and polish the inside with auto wax. Then pour in plaster of paris to a level to the edge of the glass (I ran duct tape around the edge, and let it set up thickly with a big lip on it so it had enough thickness to be handles gingerly.) Then you simply carefully roll it back over, and separate the plaster fromthe glass (it should pop off) and then paint/po.lish and you have one heluva durable buck for drooping production quantities of glass over it! The only drawback with plaster of paris is that it's easy to mar the buck, and it cracks eassily---hell it even cracks when it's drying! But it's cheap, and a couple of bags should do you just fine. With some good release compound, you could lay fiberglass over it, and make a very neat looking filler plate---but some different procedures would apply to construction of the buck and for grafting it to make a solid hatch... Good Luck. You will be amazed how easily it works once you heat this sheet to the right temperature. It will become flimsy like a big sheet of Lasagne! Just don't heat it over 320! (This was for the stuff I was using---the new stuff may have different characteristics) I was concerned about preserving the shatter-proof characteristics of the product, and from literature they sent me 320 rings a bell as a temperature you didn't want to exceed as it would start some crystalline changes that would weaken the product, or set up cracking or crazing or something like that. There is about a 60 degree range where you can work it with no degredation and it becomes very easy to form in this range. I was making vases by draping it over bowling balls and sitting them on a flat table top, all that kind of artsy hippie sh*te you do when you are in your early 20's! Anyway, I'm sure "Lexan" put into google will return some meaty bits of information on thermoforming (then again "thermoforming lexan" might be a better search parameter for google) the product correctly. As I recall I recently (within the last two years) did a search and found a nice website that had all sorts of infomration on it that was helpful. Anyway, the 60 degree working range was why I used an old salvaged oven timer---it seemed to handle the ampreage with no problem, and was relatively consistent in ti's operation when sat on the outlet hole just above the center of the sheet. Again, Good Luck. Post back with how amazingly easy it was so more people start doing it!

just a friendly reply to John Scott's comment on my contribution to this post. Please don't misinterpret my statement as something it's not. What I meant is building something that is unbalanced is usually unproductive and somewhat(IMHO) dissatisfying. You have to understand I started with a triple mikuini blowthrough car with around 250 rwhp on skinny tires. I did it because it was the thing to do... Lots of power in 1985 for any Z with a six. But I was troubled with lack of traction and kept thinkging "I need to get this power tothe ground". I ended up flared fendered with 395's in the back (Dunlop Racing Slicks) and 295's up front. With this combination I could yank and bank like nobody's business... so then the evil cycle of demented power kicked in and I figured "Well, they don't do a rolling bunrout at 60 in third gear, so I can use some more power..." And then built more. What a mistake---I could not get these tires in the USA, and ended up settling on some 265's in the back, and 245's in the front. Nowhere near filling the tire wells as satisfyingly as the old 345's did. Somewhere along the line I realized in my head that for a street going wannabe dual-purpose car tempered performance is the key. For straightline power.....well.....uh, I took up Land Speed Racing. So I guess it's the Teutonic Genes that make me a stickler for Technical balance for a road car, and the power crazy vehicle for a Land Speed Record. For the diseased German Genes in my brain, this makes perfect sense. While turning brodies may be a heluva lot of fun---all it really does it waste expensive rubber. I temper my advise to newbies to learn to drive the car first, then add power. To this date, most have thanked me for that advice. Knowing the beauty of a technically perfect turn and appreciating it's execution costs FAR less to those on a strict budget like most newbies are, and this will be with them in whatever vehicle they drive, not just the Z. I would rather enjoy EVERY vehicle I drive, not just one special one. While one may grab my heart, driving them all is my goal. And driving them well is a lifelong pursuit.

1)lay some cinder blocks in a square on the concrete driveway. 2) knock out some holes so you can lay your heat guns on their sides, and blow into the center of the square---four guns could be used. I would think the $19 Harbor freight specials wouldn't be too bad a hit... Make these holes about halfway from each end of the square. 3) lay some conventional bricks like you were going to make an ornamental diamond inside the first square. The heat from the heat guns might just blow on those bricks. If you have fire bricks, use them here! Basically you just need four bricks or rocks to act as heat diffusers / buffers and supports. Failing in finding fire bricks, my first oven was made using tin cans as the supports! 3)lay some 3/4" plywood atop these four bricks. Use sheetmetal scraps to prevent the diffused heat from blowing directly on the plywood as it can be 1100 degrees, and make the wood smoulder 4)cover the cinderblocks with some more plywood with a hole in the center to let out heat. Use a sheetmetal scrap to open or colse the hole to help build heat faster... I hope this isn't getting to obtuse---but are you getting the picture? Basically you want to trap the heat discharged from the guns in as small an area as you need to heat the polycarbonate. You lay it on the shetmetal cover of the first piece of plywood set on the bricks. If you are daring, you can skip actually picking up the whole board from inside when it comes time to drape the plastic---you can pick it up with tongs at two opposite corners, and just drape it floppily over the buck. This is how I made rear windows, side windows, and quarter windows out of 95% Light Blocking Greay Smoked Polycarbonate. It looked Bitchen, and NOBODY could break into my freakin Z again with a simple spring powered centerpunch or hammer---unless they went after the windshield, and wanted to crawl through broken glass. (Theft of personal property is the mother of invention!) Good Luck if you need further clarification ask, and I'll try to be more detailed. Good Luck! You can get the polycarbonate in the right thickness to fit the stock rubber trim for the rear window from McMaster Carr. You cut it with a razor blade, and you can just "shrink" the stock sized hole porportionally, or turn it into a Triangle for that matter!

You know what, with that setup, you will ABSOLUTELY need a bypass valve that is open on vacuum operation. If you don't plumb the float bowls to the same pressure as the barrels, you run into problems. so the plenum for the front of the carbs has to take this into consideration---if you do not, every time you lift throttle, the fuel will be pushed up the mainjets and totally flood the engine due to the 14" of water you get! This is how "modulator rings" work on a turbo blowthrough. When at low airflows, they do nothing , but on-boost they act as a venturi at the front of the carbutrettor putting the main section of the primary and secondary booster venturi under a slight vacuum condition compared to the pressure present in the plenum, avoiding hte "on-boost cough" and as boost increases, so does the fuel enrichment regardless of mainjet size! This is how Maserati got by iwth comparitaviely small main jets, but still managed to run rich enough under boost to not detonate! I assumed full time blower operation. I would not use the triples in a bypass situation with a blower---to be brutally honest, I would go with a Wet Four Barrel setup before killing thetriples I think. Sell the triples to someone who iwll give you $500 for them, (like E-bay) and then use that money towards an SDS or Megasquirt. The packaging of an EFI bypass supercharger on an L is FAR easier. There is a gent in OZ who used a bypass compressor from a toytoa on his 510, then was selling the setup later complete with the dizzy and drive off the cam he devised! The EFI route will be far supreior in every aspect. Costs are declining forthe technology every day, and over time more and more used systems are coming on the market at unbelievablely low prices!

all I have to add tothis is that 8.5 compresion is NOT "high compression" for a Turbo Application, and in fact I believe the general consensus will be that it is the ideal compression ratio with which to start! If you want "top end performance" ditch the stock manifold---it hinders you above 5500... Other than that, 250 tothe wheels will be a breeze to achieve. 300 will take some work, but you might consider Megasquirt2 when it comes out... Eventhe basic Megasquirt-n-Spark program is loads better than the stock ECU in terms of throttle response and fuel mileage off-boost.

327 brings up a good point: peak torque, or where the "flat spot of the torque curve starts" is actually where you want your engine to be for top fuel economy. For more perfromance, yo ucheat the curve towards the "peak point", but ALWAYS want at least 500 rpom below the peak so when you stomp on it, you get IMMEDIATE response (and might I also add....BOOST!) while still having a meaningful range of rpms to run through before upshifting. If in top gear, you pull storngly to the top speed. My car gets 22mpg towing an 800# trailer with these specifications above, despite "screaming" at close to 3500 (anywhere from 3100 to 3500, with occasional extended speeds of 4000rpms...) So higher engine revs don't necessarily kill gas mileage, as well as lower revs don't automatically give better mileage! 327 has a good point and should be well heeded.

I temper my comments here far more than at the "other site" simply because there is ACTIVE moderation, and there is really no need for "the people to police themselves". Someone says something out of line, and they are dealt with. I only wish the same could be said for the other place. I don't know that approving every post would work, and like I said other places I wish I knew how to make a filter for new posters (say with less than 100 posts) that would actively "read" their question, AUTOMATICALLY perform a search on the keywords, and if there is more than Xx% of matching keywords, Kick the post back to the originator without posting it with a suggestion of the first 25 or 50 relavent hits in the body of a message that stars something like "Your question appears to have been asked and answered Xx times before in the past six months, please read these topics first before rephrasing, clarifying, or otherwise editing your post for a more productive use of other member's time" And then auto-lock the person out of posting until all 25 hits have been clicked on. To me it SOUNDS simple enough, but I am boggled by what it would actually take to implement this feature in real code writing! So It will probably be a dream for a while tocome until public domain "carnivore" programs become available...

surplus record is fantastic. I am keeping my eyes peeled for a rotary table now that the Bridgeport is bought and paid for! So is the 4X10 layout table that weighs 2800#, the power band saw that cust 6X steel billets, my 48" rusty slip rollers, and the 350Amp TIG machine.... Yeah, I went on a shopping spree. You can find what you want, and for the right price, too! I bought the mill out from under a Harley Shop that was dawdling about coming over for "photos" of the machine! The owner said "What do they need photos for, a Bridgeport is a Bridgeport I mean, how different can it look? Of course the shaper head on the back of the turret makes it all the more tantilizing! Muahahaha! Now to get them all on a flat bed, and over to the house!

Pressure is usually adjusted by spring bias and you can adjust it fairly easily if you think it's too touchy or sluggish... Most Japanese Systems are all made by the same company anyway. Teh only time you would run into strange compatibility problems is seapping American and European, or Japanese and American, etc etc etc... Except for Jaguar---the old KJ6 and XJS had Saginaw Steering Gear power steering, my father in law was a foreman on that line. They distinguished the steering boxes by the size of the quill shaft connecting the wheel to the steering setion of the box. Corvettes had a very stiff and torsinally rigid shaft, so they had a touchy steering response. Jags got a soft shaft, which softened the steering response. But from what he said, everything they produced all worked on the same pressure, Response was dictated by internal parts that moved valves and etc.

"The car is screaming on the hwy 65mph@3100rpm (not cool). Is there a way to resolve this problem? " 60 or 65mph at 3100rpm IS cool, and NOT a problem! You are just below peak torque at cruising speed on the highway, making for PERFECT top gear roll-on throttle response. You will be in the HEART of the tourque band on a stock engine, and will accellerate briskly. This is not a problem, and is not affecting your terminal top speed, either. If you speedo was DEAD ON, you top speed would theoretically be 120 to 130mph at 6200rpm. My old Fairlady Z with a factory direct-drive four speed and a 3.70 gearing, with STOCK HEIGHT TIRES would pull 6350rpm at 200KPH. Some math involved, but that's dead on, and I NEVER had a problem with that car. Currently my 75 2+2 runs at around 3500rpm at 70mph, though that may have changed since installing the 45 series tires, so I may be running slightly higher. For a Z-Car whatever your average cruising speed on the highway is determined to be, you should gear it so the vehicle is turning around 3000 to 4000 rpm (depending on perfomrance bias) at that speed. From what you tell me, your car is running perfectly fine, and there is absolutely no problem. It's not a V8 that will float the vlaves at 4800rpm...

wrong place to ask that question! I have to agree with John: most people can't drive their STOCK 240 or whatever to 10/10ths before they start gobbing in more power. More power makes you lazy as you think you can always "make up time" on the straightaways. Watch the old Corvette/Lotus battles of the early days of televised roadracing and you will see this laid out very well. A balanced machine will ALWAYS be faster than one with just one good attribute. Building a car that you can never drive to it's fullest is both sad, and a sorry waaste of good resources.

nothing horrible about cutting it, you get a sandblaster, set up a template for the window size you want, duct tape it or glue it to the glass, and have at it at about 60psi using fine aluminum oxide or slag. you will slice through the layers of glass and laminated plastic in short order. This is how shops cut down glass for chop-tops. If you have a steady hand, and a fine point nozzle, you can get away with just ductaping whatever you don't want cut so you don';t make pitts in the glass and have at it, but I have always used a sheetmetal shield. As for Lexan or Polycarbonate, you can easily get it to the "right curvature" using several industrial guns (I like the adjustable steinel) hooked to an extension cord blowing into a small "furnace" you make from bricks on your concrete driveway. Lay he polycarbonate sheet on an elevated piece of sheetmetal, and have theheat guns blowing across the bottom of the apparauts (indirect heat) to raise the internal temperature to around 300 degrees (just where the plastic will droop). Pull the cover and exhaust stack off the top, grab the oversized piece of sheetmetal and polycarbonate sheeting with some heavy gloves and slap the polycarbonate onto the back window---it will assume the same droop, and re-harden that way. Then all you do it cut it to size with a Zip Cutter like for drywall. Far easier than sandblasting, and cleaner, too! You can control the heat guns on a multiple plug outlet strip, by running an extension cord through an electric oven thermostat that will maintain and regulate the heat in your makeshift "polycarbonate heating oven"! Yeah, I had lots of time on my hands to experiment when I was younger!

hydxraulic flow and pressure are hydraulic flow and pressure. The 240 I know of used brand X rack, and the easily available and pre-made bracketry affordable 280ZXT pump to drive the racks internals. Worked just fine. I have seen GM pumps on Fords, Chrysler Pumps running snow plough cylinders, Nissan pumps converted into a PTO for a logsplitter on a front mount hitch, and GM pumps used as PRESSURE WASHER PUMPS! So the pumps are very versatile. Very versitile indeed!

I think you will need to have one helluva large blowoff dump valve to dump positive pressure off the carburettors during idle and drop throttle conditions. Surge was not the problem, it was a condition under light throttle where the plenum went to "0" pressure almost instantly, and the carbs have a presistent lean stumble in this area. They will cough and lightly pop no matter WHAT you do. The only way to stop it is to use a larger plenum sized like HKS Surge Tank, and add modulator rings as the Maserati BiTurbgo did on the Dellorto's in it's blow-through configuration. I would go wet supercharger---you don't really need intercooling with a wet system and only 9psi. Lynn Burkhardt of the Ontario Canada club runs 12 to 17psi on his blower, but he's EFI... And has been since 1995 at least. I wonder why...

woah waitaminit here? are we calling things the same terminology here? Is this FMU some sort of electronic gizmo that manipulates the injectors, or is is simply a variable rate FPR (Fuel Pressure Regulator?) As you saw in my original post on this subject, a fixed rate FPR is all you need, jacking up the fuel pressure and solving for the new delivery rate to enter this into the MS unit. Tuning around a variable FPR would be actually simple if you know what maximum pressure you run at under full boost: simply do the calculation for terminal total flow from a single injector, enter it as the injector size in the Ms during setup, and compensate off boost by lowering the VE number to give less duration and fuel delivery accordingly... Fairly simple, actually, and would get you VERY close the FIRST TIME OUT instead of GUESSING (which is what many people call "tuning"). Some basic math beforehand makes for a lot less headaches and things that go "boom" afterwards...

I thought I answered that before. The owner of the car is Dave Glidewell and he is a longtime Member of Group Z of SoCal. The engine was dynoed around 345, which is not really pushing this setup, I have seen 450+ from these type of setups using proper surge boxes in Japan in the mid to late 80's... The smaller box he has on there is horrendous on the transient suffering from a "0" boost condition at speed with even the stock compressor. There needs to be more plenum volume so slight transients do not result in you going into boost immediately as there are problems with using SK and Mmikuinis in this service (and webers are worse...) The only carbs really set up to handle this kind of application out of the box are Dellortos with the Turbocharged emulsion tubes, sealed throttle shafts, and the proper modulator rings at the front of the main venturi... Dave and I have run these systems for a looooooooong time, I first installed mine in 87. I saw the light. Standalone EFI is FAR superior if you want a daily driver in the heat. I did drive mine daily to and from work in SoCal, and averaged 17mpg with it (better than some guys with SU's!) but when you flog it don't expect anything much more than 5mpg... So that's about 70 miles before you fill that tank again with high-test...

exactly how does something "emulate" larger injectors? I mean, I can see if you jack up your fuel pressure, and use it as a variable in an FMU it would back down duty cycle "like" larger injectors were installed, but if you do the simple delta equation of fuel pressure and delivery before, and fuel pressure, delivery after, and solve for delivery after, and enter THAT number into the Megasquirt, it, too will "emulate" bigger injectors in the exact same way! The FMU should be totally unrequired with the Megasquirt, it would "tune around" the FMU just like you could "tune around" a AIC---but you really don't need to, if you only have one set of injectors, you can tune it all with the MS, regardless of you fuel pressure... BTW, you can actually buy two MS units, and run them on two different banks of injectors, making for a 'staged' injection scenario. Basically run spark and fuel to full duty cycle on one unit, and set thesecond bank of injectors to come on where the first unit's duty cycle maxes out. You simply make the first bin about 500rpm below where the injectors go static on the primary system. This would allow about 550cc per cylinder from a set of two stock Turbo Injectors... And if you used those 550CC ford units from the TBI engines, you could have around 720CCs... Now I got Bastaad whirling, don't I?

To clarify, this is for a swap into an early S30 model, and not a replacement for an S130 unit, correct?

turbo manifold is identical between L20 and L28. The stock L20ET made 145HP stock, so 200HP is not a big deal. Boost on. It's late, I'm tired. Maybe more time to read and see what you really need, later. Anyway, the stock L20E can take that boost no problem--crank into it as any other N/A to Turbo conversion: Add that rising rate FPR, or standalone and some L28ET injectors and you should be good for your HP range stated (225?) with the right boost and some small intercooling... Hey Frank, you get photos of the Orange Truck? Too much for Dad, huh?

On a non-intercooled turbo application, the discharge temperature of the turbo is easily figured, through sijmple physics. The compression ratio will determine the temperature along with a variable like the compressor's efficienfcy. Simply put, 100 degree ambient air pushed to Xpsi will be approx 270 degrees. Add that temperature to the compression ratio of the engine, and you will quickly see the compression in the engine being closer to 7.5 or 8:1 will also raise the air temperature some more. And BOOM! the gas lights off if you have cheap stuff... In reality due to camshaft overlap and how dynamic compression works on a rotating engine, the compression ratio (actual) in the engine while running is somewhat lower until peak torque where it reaches nearer the actual design ratio. So basically, you are limited in a non-intercooled application to the compression ratio, it's resultant heat, and then the engine's effective compression ratio raising the temperature in steps to a critical point where iognition wold occur. This is why some Diesels use rad high-boost turbos with no intercooling due to the heat produced through the turbocharging. Throw in an intercooler, and all bets can efectively eliminate the turbocharger's heat, and all you have is intercooler out temperature being the effective ambient temperature for purposes of determining ignition temperatures in the combustion chamber. Basically, the Turboicharger acts like a "variable compression ratio" component. With the cumulative heat, a low-boost turbo's output can be equated (as well as having detonation characteristics comparable to) a high-copmpression engine (14:1 and up!) But it's late, I got a killer neckknot, and can't expound any longer on any more of the question. maybe tomorrow! not enough energy left right now to get into density and AFR variations. But this heat is how the ping and ignition happens. Simple Physics.~

yer too picky! "Tight valves burn"! You learn that "Quiet Valves Burn" If you drive an old air cooled VW for any legnth of time... The valve lash noise is part of the engine harmony. It's not natural for a solid lifter camshaft to be quiet.

450? Where did you get that low number? Electromotive was cranking out 580HP on stone age fuelcontrol only EFI (TEC1) back in 1983... That was state of the art, then. Now with modern EFI controlling both fuel and spark, that number is available for street cars...

BAE, Crown, and SK all made the adapter you speak of... The Corwn one was the worst of the bunch, being made of mild steel tubing. But the SK unit used a stock exhaust gasket, and sealed great. I still have one, for what I have no idea, but it's just soo cool looking, and it doesn't take up much space.... I have seen the BAE unit, and it looks a lot like the SK unit, except the SK unit uses a T3 flange.... Cool, huh?