Clifton

I wasn't sure why you said use an autometer tach when I was asking about 280 tachs. I'm trying to keep this car as stock looking inside as possible, hense the stock tach. I know autometer gauges are good, I've been using them for over 10 years and my 71's dash is full of them. This car is just a budget build up to run around in.

The battery is just to start the motor. The alternator is what powers everything when running, but at idle that fan might exceed the alternator on an old Z.

87-88 turbos had 3.90. 89-92 turbos had 3.70. Non turbos were higher, I beleive 4.10 but not sure. Turbo cars had LSD. I've heard NA cars with the sport package also had the LSD but not sure on that either. There will be a tag " LSD" on the cover.

Thanks Drax, that's what I was looking for.

The 7M motors is in, just need to finish up the loose ends (wiring). How have you guys with coil packs hooked up your tachs. I know I need a 280 tach. I have a tach output on the stock ecu but don't know were this will need to go on the tach, if it will even works. I did a search and found the same question twice but no answers.

A true "race car" on the street is something I would not drive everyday. You here everylittle peice of debris the tires pick up, It's loud, stiff, and you'll wander and bounce down anything that's not as smooth as a race track. I would do a cage not a bar. I would also not do a ZX due to weight, you want to be as light as possible and a stripped and gutted ZX with no windows is still heaver than an S30 with interior. I stripped my interior and scraped all the black sound proofing off the floor then painted it with can paint to match the exterior. I need to do the occasional touch up but it works good. I rewired it, lexan hatch window, fiberglass doors, hatch, and hood. Made an aluminum dash and removed everything that was not needed all to get it as light as possible. There's some pics if you click my link at the bottom.

"The device that slows the rpms when decelerating is gone"I would put this back on. If you are not geting complete combustion on decel and are a little rich on decel, the throttle being slowly closed even for a brief second should allow enough air to enter to burn off the excess fuel. Try to hold the throttle open just a little for a second next time you decel and see if it still back fire. Most modern EFI cars have a fuel cut if the TPS is closed and above a certen rpm and or a dashpot to prevent the throttle from completely closing fore a second. I don't know what to say about the knock. Maybe rod bearings. You could try to isolate it by pulling plug wires, or just leave it advanced. As long as you don't get to far advanced (36*+ total, depending on temp)and knock from that.

It can't be any worse than the stock L28ET manifold . Flanges should be around $25 for both. I don't wish for twins, I do wish for T66 but $1100 is alot when my V trim T4 gets the job done, although it is my HP limiter. The 60-1 and 62-1's flow alot but not as much or as effeceintly as the T series, alot cheaper though. To do all over again I would of started with a T series.

My $.02. Keep it simple. I would weld on a T4 flange and wastegate flange to your 7M manifold and run a 60-1, T66 or whatever. Twins will not spool up that much faster and if road racing your rpms shouldn't get below 3500 rpm anyways. Also there will be twice as much custom plumbing to deal with and then you still have the exhaust. I run a full T4 on an L28 and only use it for roadracing and I have no problems with lag if I keep it in the powerband.

When you retard it more it knocks? I think you mean advance it more and it knocks. Are you talking light pops or gunshot sounding backfires ? Are you running aftermarket exhaust with low back pressure. If so then some light pops is not uncommon. I f I go from full throttle to closed throttle I can get a bang but from cruise to decel nothing.

You asked how to blow through 2 SU's? I thought you were going to build a fast N/A car, then it was a TBI, now it's twin TBI and turbo. Asking "how to turbo something" and "what do I need to complete a project" is completely different. This is probably why you didn't get the answers you were looking for. If you say you are going to run twin TBI then you would have to know how the system you are talking about, cause I doubt anyone here would know or even want to know as there isn't a reason to use it as port injection is better and manifolds are reaily available. TBI is great for 80's Chevy work trucks though.

The old Crown turbo kit used 1 SU but it was a suck thorugh. Haven't seen any blow through SU's. I know you would have to either plug the float bowl vent or route it to your pressure box. If you can fab the plenum's your self and aren't into it for much I would try it.

I made 360 rwhp @ 15 psi and 417rwhp @ 22 psi. My turbo is my HP limiting factor. There are other things that will limit your power before the ex manifold.

That torque is huge. I'm not trying to be negative but your injectors will keep you from making anything more. If you use an 18% drivetrain loss your HP is around 368 which is about all those injectors will support no matter how much boost is run.

Arizona Z Car is coming out with some anodized aluminum ones. Don't know how soon though.

I can't give you exact numbers but I do know the GN turbine wheel is larger in diameter than the Z wheel. So if you use the GN turbine housing you'll need the GN turbine wheel too. I have a stock 86-87 GN turbo with a .63 a/r on a Toyota 3.0 V6 truck. It will make 12 by 3100 rpm. Don't know what that compares to with a stock turbo on a Z as it's been to long since I've had a T3 on one. By the way the GN compressor is an S trim, doesn't flow too much more than a Z's 60 trim T3.

Go to the Turbonetics web site and do a little research on compressor maps. If you want a T3/4 you can get new T04B's (V or H) for $400 and E's for $450 ( 57 or 60). Either will easily make 350 rwhp. Then just swap out your turbine, turbine heat sheild and housing and you have a nearly new turbo that will bolt up. Or just buy what you need if your center section is fairly fresh. Alot of the Ebay stuff won't bolt up. Lag goes along with having a turbo. Unless you are going Full T4, P or Q trim and larger than .81 I wouldn't worry about lag. Any T3/4 will spool fast enough.

It is no more work to run the E/MSD system or coil packs. You have to fab a crank sensor bracket for both systems and mount magnets to the pulley wich isn't hard. I guess you have to run different plug ends on the coill packs, no biggy though.

2" turbo to intercooler. 2.5" from intercooler to TB. I ran that and the 3" turbo inlet all on the driver side. Needed a litlle trim though.

EM-4 E. Stock turbo bottom end. P90 head and everything is is not stock. 420 rwhp @ 22psi.

A turbo pistons top ring land is about .180" N/A is about .140". It's hard to get a good reading as the caliper doesn't fit into the ring grooves. I've seen 3 sets of turbo pistons and they all say P90 in the center of the dish. Don't know about material differences but the extra .040" on the top ring land is reason enought to use them.

Although not much help for you, US model 240sx's with HICAS have a viscous LSD. They are hard to find though.

Do you have EFI? I'm running a fuel cell and had to put a sump in it to keep it from starving in the turns. The foam in them just slows the slosh down. You may end up needing a surge tank or sump.