Scottie-GNZ

If the rod slips on the lever with no tension and the boost is 15psi, then that is what the spring pressure in the cannister is set to deliver. That is not unusual. The stock GN spring delivers 12psi and I am using a HD version of that one that is set for about 16psi. The turbo itself has nothing to do with the control of boost.

Yo, not quite sure I understand your problem. Are you saying it is not a standard WG actuator and the minimum boost you get is 15psi? Did you have the pull on the rod ( :D ) to get it on lever? The amount of boost you get from a internal WG actuator is controlled by 2 things, 2 spring pressure and the length of the rod. The default is the rod slipping on the lever with no tension. If you shorten the rod then you pre-load the spring and boost goes up. Is it possible this non-stock actuator has the wrong length rod or the rod is misaligned?

Trying to find a pic of that dual-port cannister but could only find one in Turbonetics with the "Maxima" WG setup. Is that the same cannister you have? Do you know what the default spring pressure is. I need 12 or slightly less. Rick, that MSBC-1 is a loaner for a trial with no obligation. What are you doing Saturday? It looks like we are taking Misred (RX7/GN) to Bradenton for some T&T at a track rental event. Looks like I will have to drive as Mike is slightly incapacitated at the moment as you can see in the pic. Think we can take it to the level which would be the 10.70s still with "low" boost. If you can make it I will bring the MSBC-1 and you can look it over but I doubt we could pop the box open to se the guts.

Rick, are you saying you have an internal dual-port WG actuator? If you do, I LOVE YOU, MAN! Err, Ok, you are my good buddy :D Rememebr what we talked about the other night? Well, someone just loaned me an Innovative MSBC-1 to try out and buy if I want it. This thing works best with a dual-port, internal or external.

My goodness, what a coincidence! I am also looking for one even if I have to do some adaptations to make it fit GN turbo. Does anyone know of any OEMs that used them?

Like Lockjaw, I want to clarify one thing before anyone thinks I am slamming that car or disputing the claim. I clearly stated the reason for my conclusions in BOLD TYPE.

Good luck. It will be great to have another street-driven hybrid in the low-10s.

This is one of my favorite topics of discussion and I agree with Alex. If there is unlimited budget or this will be one of those "...and this turbo engine must run 12.1 on the street with pump gas" projects, then go for the gold, err forged. Being able to run 12.1 with a turbo engine requires ONE thing: HP AND no detonation. HUH? He said one thing then listed two, and that is correct because those two things in a turbo engine are one and the same. You cannot make HP if you have detonation. Forged pistons do not make HP or eliminate detonation. They stand up to detonation better. Regardless of whether you use stock or forged pistons, you still need to avoid detonation to make the HP needed to run 12.1. The way to avoid detonation is to have an efficient turbo and I/C, free-flowing exhaust, adequate fueling (pump/FRP/injs/octane) and good engine management system. yes, thats right. Those are all the things that make HP. That is where your focus should be initially. Next, having all that HP is useless if you cannot put it to ground and cut a decent 60'. Tires are critical and street tires are useless. Wider/bigger is not always better. Here compound is the key. Next, do you want to run 12.1 on pump gas on the street or do you want to run 12.1 on the track? I am not into street racing so I have a different perspective on that. If you want to run 12.1 on the street with pump gas you have to build an engine that can run low-11$ all-out then detune it for the street. If you want 12.1 at the track, then have a way to control boost so you can run say 13psi on the street with pump gas then go to the track, add some octane and crank up the boost to say 18psi. So, to sum up. If money is no object, go for all the trick stuff like forged pistons, headers, etc, but you still need all the components to avoid detonation and provide maximum launch traction. If budget is tight, freshen up the head, go for the other items and be patient and learn how to tune, tune, tune, tune and you will be rewarded. If you take the time to understand the basics of turbochrging and fuel injection and learn to tune, you won't have to buy components that can make 450hp to make the 320 required to run 12.1. The 2 biggest gains you will find when wanting to go quick at the track will cost you NOTHING, NADA. They are learning how to tune to maximize what you got and being one with the car at the track. Both take lots of practice and patience and unfortunately most folks cannot deal with that. You are not going to run 12.1 the first time out. Not even close. It might take several trips to the trap to attain it. Just remember, every .1 in the 60' affects the ET by .15, and that is where you make the most gains when you start running.

I do not think I could tell you if the hub and axle mods would work. You also need to fab up a front diff mount, get the correct driveline angle and make a driveshaft. No problem on the 3.08/700R4 combo, but the C4 tire is a 255/50-16 which is 26" and taller than most Zs use. Make sure you understand every mod that will be required and understand the cost. It will not be inexpensive. Here are some pics of my front diff mount that I designed to adapt the C4 diff to the stock Z x-member. You are welcome to copy the idea. However, note that it is a solid mount, which I decided on specifically for the kind of racing I do.

Maybe it took so long to get to the finish line he thought it was a 1/4-mile :D D: Oh, I kill me

Here is a formula to use as a rule of thumb: (inj cc / 7) * # of cyls = HP @ 80% DC It is just a rule of thumb and if you run a higher base FP or higher DC%, the HP number can be much higher. However, there is no general rule to apply as to how far you can go. Some engines prefer to run richer and some get mean when they get lean. The leaner the mixture, the less fuel you use but the more danger of detonation. One thing is for sure, the better the fuel management system, the more efficiently you are at maximizing the injs.

I have not given you a straight answer yet, have I? :D That is probably because I am not sure exactly what you have or plan to do with it. Still need to know what tranny you have and are you planning to drag race the car with really sticky tires? I need to caution folks to carefully consider what I did with the C4 swap before they decide that is what they want. I went with a 3.08 for somewhat similar but different reasons. I needed a LSD but I needed to run 130+mph in the 1/4 and keep the tranny in 3rd and the engine around 5500RPMs. On the hwy I am running a tad under 2000RPMs at 72mph in OD and LU with a TH200-4R. The GN setup can deal with that because it is a low-revving, mild-cammed grunt engine and the slightest pedal pressure kicks it out of LU and a little more kicks it out OD. Not sure how an NA would deal with those low revs. Once again, depends on the tranny you are using. If you are using a T-56, you do not want to do this. Some of the other LT1 cars can chime in on how this engine deals with low revs and high-gearing. Hate to see you do a mod that might cause damage because you end up lugging the engine too much or end up having to upshift on the highway. The C4 rear brakes are 11.4" so you better plan on having similar or larger in the front or a prop valve which would then defeat the purpose. The C4 uses the GM 5-lug pattern which is 5x4.75". Unless you look for rims designed for early GM rear wheel drive cars, just about every late model GM is going to have a FWD-like offset, even the RWD Vette, Z-28s, TransAm, etc. E.g., the wheels I am using for my slicks are late Z-28s 16x8 with a 6" BS ... If you want a matched set of wheels, you have to use an oddball adaptor in the front or find a wheel for early GMs. That sort of rules out some of the nice late-model GM wheels which are super lightweight and can be had cheaply. The 280Z stubs are the strongest and you should have them if you plan to drag race with sticky tires. If not you can probably get away with the early ones. Not trying to talk you out of your idea but I have no idea if it will work and just want to caution you on things you might not have considered.

Based on the timeslip, that car is not making anywhere close to what he claims. If you assume it weighs 3600# with driver, the 12.88 @ 122.37 (registers more HP) is about 440rwhp and 530 at the flywheel with a 17% drivetrain loss. I know he had lousy 60' times but if he had what he claims, he would have registered a much higher MPH, like 130. Maybe he did register that number on the dyno, but at the track he lost 100+hp based on his time. Slow 60' times will affect ET but not MPH and sometimes the MPH is higher with a slower 60'. Even if he granny-shifted he would have had a big MPH IF he had his foot to the floor. I am running 50# injs, 525cc, and I am in the 90s% DC range. I suppose if you cranked up the FP with the 555cc injs you could support 570+rwhp.

Since you have an LT1, I assume you have a T56 or some automatic with OD and LU. I would rather see you go the R230 route with a 3.54 LSD than try to do something that no one else has ever done.

I did a little write on how to mod the SVOs to fit the L28ET. It is in my old L28ET webpage which was hosted on zdriver.com. I left it there in case anyone could find it beneficial but now it is not accessible. I have no urge to fix it or rehost it so if anyone still wants it up, contact zdriver.com and see if they will fix it.

Any luck? The problem could be anything but more than likely it will show up as an oddity in either IGN or DC in Gauge 2 mode. you just have to know how to interpret it. E.g., if you look at your IGN and IGN RET maps, you would know exactly what the timing should be for 4500 RPMS & 8psi boost. Lets say it is 25*, derived from 33* advance @ 4500 minus 8* retard @ 8psi boost. If IGN in Gauge 2 is reading 8* under those conditions, then it is probably the result of the knock sensor as suggested. Either real knock or the knock sensitivity needs to be adjusted. Make sure you have good IGN & IGN RET maps so the timing is accurate. I would not waste money cleaning stock turbo injs. Get a set of used SVO 30# injs and have those cleaned then reprogram the SDS. Here is where you see one of the benefitsof a programmable system. No worries about the bigger inj making the engine run rich at idle or off-idle.

Yes, 4-spd with a 3.36 just like the early S30s with the 4-spd. That is why they are so rare. I had a R200 with the 3.36 but it was still too tight a gear for me and a lucky person on this forum now owns that rare piece. For people like myself, Trevor and others who need a R200 with a gear taller than 3.54, that is when other rear-end options get serious consideration. Here is the scenario. Find a 3.70 LSD if you are lucky. Find a R200 3.36 if all the stars are aligned and Bin Laden & Saddam turn themselves in or buy a set from NISMO , pay a shop to do the R&P swap, new bearings while you at it, get a set of CVs, get the CV adaptor and strong stubs from Ross. You are well into 4-figures, if you can find the first 2 items and hope they are in good condition.

I guess I am curious why you would want to do this.

'79 ZX 2+2, 4-speed to be exact

What generation? C3 or C4?

OK, this will be my last post on this topic and it will be an idea for you to look into. It might not sound as exotic as your initial dream, but..... You love the Z and want to road race it. You love turbos and want a lot of HP. Scour the hard-core racing rags and look for someone selling a rolling GT2 chassis that has a good racing record. Next, get an RB26 and the appropriate tranny and start out learning and being one with the car. The Rb26 has 600hp potential w/o much internal work. Trust me, you do not want or need more than that in a well setup GT2 Z-car.

Austin, does the video show Gauge 2 mode? If it is not terribly large, go ahead and send it to me but no promises on what I will see. Hopefully bad injs will show flaky DC behavior but there is certainly a difference in the load when in N. Strange.

Good advice so far. If the engines revs past 4500 in N, then you need to check the DC% when it starts going flaky and if it shoots up to a very high %, then the problem is fuel delivery. Check the following: - Stock pump will not cut it! - Kinded fuel line - If you are using the stock fuel tank with a front pickup, you might be getting cavitation with the fuel flowing away from the pickup under acceleration - Clogged fuel filter or internal screen/filter in the pump if it has one - If you are using the factory wiring, check for a bad conection or corrosion, then completely rewire the pump with 10-gauge through a relay and using the factory wiring to trigger the relay

All this discussion about how easy it is to make 1000hp has gotten out of hand. I giggle when I hear the comments about SupraTTs and other factory engines making 1000hp without any internal mods or just port the heads and turn up the boost. That is just nonsense and those that make the claims in the magazines or on forums are lying. Just think about it. A 3.0L 6-cyl engine making 1000+hp is making as much HP as a stock L28ET in 1 cyl and put another way, .5L!! No factory crank can handle that. Let me clarify that and say no engine available in a production car since engines like the Buick StageII are factory engines that can "easily" handle 1200-1500hp. There was a reference to a 1000hp car that spins the tires at speed just needs more down force. What car could possibly generate more down force than an F1 and even with that downforce, those drivers that do not respect the 750-800hp loses it. A 600hp, 2300lb tube-chassis Z is more in line with what is needed to get the job done in SP. It might not have the ring of 1000hp, but it is realistic, reliable, less costly and driveable. In the hands of an experienced driver, such a car is still a handful.

I read the list thinking I would find a lot that applied but was surpirised. 1. Emissions? FL? At least not in my county 8. A couple of times 30. 125mph 33. I wish 42. Yes.