TimZ

Yep. Look how close the spark plugs are spaced. Also notice that they are not in a straight line. It's two VR8's in a V. ..You are familiar with VW's VR series motors, right? They are a very narrow angle V arrangement - the banks are close enough together that they only use one head. That's why you only see two heads on the W16. It does mention this in the tech specs, btw.

It's not a V16, its a W16. Basically the same idea as VW's VR6, except it's two VR8s arranged in another "V". Basically a 16 that packages like a V8. Very cool.

This is correct, assuming that the 81 engine still has the '81 head on it. The fact that it's carbed makes me a little suspicious - were the '81 heads still drilled for carb intakes? EFI heads have little notches at the top of the intake ports to accomodate the injectors. Do you know which head you have (should be stamped on the head - something like E88, N42, N47, P79, or P90)?

If he is never going to tubocharge, then the 1 bar sensor is much better for his application. If you assume an 8bit A/D converter in the EFI system, using a 3bar sensor for N/A is like going from 8 bit resolution (255 discrete steps) to a little more than 6 bit resolution (85 discrete steps). btw, 1 atmosphere = 14.7psi 1 bar = 14.5 psi

I thought the only reason to convert to a cable linkage would be to accomodate a different throttle body that didn't work with the stock linkage. Given a choice, I'd go with the mechanical linkage any day. Does that engine have a BCDD (Boost Controlled Deceleration Device)? You'll have to look in a service manual to find out probably. RPM hanging is a very common symptom of a malfunctioning/misadjusted BCDD.

You really don't want to rely on the EGO feedback to fix big holes in your fuel delivery curve (I assume the DFI has a VE table or something equivalent, right?). I always leave the feedback off until the VE table is in good shape. The EGO feedback simply cannot respond quickly enough to compensate for big swings as you go through incorrectly tuned cells in the table. The result is pretty much what you described - inappropriate swings in the injector pulsewidth and bucking and spitting. On the voltage, you might want to check the connection at the regulator - I am running a 140A GM alternator, and found that the connection to the output post have come loose internally and was making intermittant contact, and this gave similar results to what you describe. I agree with blkmgk that unless you have a wideband sensor, you shouldn't rely on the readings as they move away from stoich. BUT, I think it's pretty safe to say that if the narrowband sensor says it's rich it really is rich and if it says it's lean it really is lean. The inaccurate part is in the "how much" it says you are rich or lean.

Okay, I have never used the Valvoline synthetic fluid, but would you care to elaborate on this? Aside from sucking, what is wrong with the Valvoline synthetic brake fluid? The clutch hydraulic system is not a particularly demanding application for any brake fluid that meets DOT3 or DOT4, so if it's unsuitable for a clutch, it would have to be downright dangerous for a brake system. So what gives?

I would pay close ttention to the quality of the harness install. If you see things like wire nuts or wires just twisted together to make a connection, I would walk away.

Exhaust Gas Recirculation - it was used for emmsisions control.

As long as you are simply cutting the injector pulses off clean (i.e., not in the middle of the pulse), the fuel cut should work fine. This is what Vishnu generally does on their TECII - controlled Subie setups. Fuel and spark would be even better, but I would be leery of spark cut by itself. You would be dumping alot of unburned fuel and oxygen out the exhaust port. Just sounds like asking for big fireballs.

Well, this is not quite right - 1.2ms is approximately the minimum pulsewidth that a low impedance injector can tolerate without becoming unstable. This means that you will need to have at least 1.2mS of pulsewidth at idle to have any hope of getting a stable idle. Note that this dictates a minimum amount of fuel that you can inject into the cylinders at any time, and if this is still too rich, you will have a difficult time reducing the fuel delivery more. This is where jgkurz's suggestion of backing the idle timing off comes into play. All else equal, less timing = lower idle speed. So, if you reduce the base timing, the IAC will have to open more to compensate. The result is more air for your minimum amount of fuel (i.e., it gets leaner). Using this method, I was able to get stoich idle (well, ~14.4) using 72lb injectors and a mild turbo cam (Isky L475). My base timing was down to about 5 degress, btw.

Yes, James - of course you are correct, however I would contend that only 2 s's are required to quell the 4th harmonic resonance (using the S = sqrt[harmonic] rule). Anything more than 2 s's is pure bling, and could even cause negative harmonic suspension oscillations, which are highly unstable.

Pete - I would contend that it doesn't even help then - if properly recirculated, the output of the BOV goes back to the turbine inlet, which is almost certainly at a lower pressure than atmospheric. Bigger pressure differential = better function for a BOV. Although you mentioned that you didn't want to discuss this in your original post, you did give the appearance that perhaps you were worried that it might be too loud. This implies that you thought that there was some advantage to venting to atmosphere, and weren't just worried about whether the added bling factor would make you look cool enough to your idiot friends. In that context, Pete's and others' comments were appropriate, in that they were pointing out that if you were worried about noise, there was no performance to be gained by venting to atmosphere anyway. From your last post, it (sadly) appears that maybe you were hoping to increase your bling factor, and didn't really care about whether it did anything useful or not. To many of us, this puts your question at the same status as "Who makes the brightest LEDs for my windshield wipers", which we really just don't give a shit about. If this was in fact the case, maybe you could just say that specifically up front, and then the grownups on the board won't have to waste their breath trying to help you.

As long as the diameter of the retainer is not so much larger that it can no longer properly retain the pad, I don't see that as being an issue. The thickness could be an issue, however. There are at least three different retainers for different ranges of lash pad thickness. If your retainer was not intended for a .120 pad, then the pad could be riding too low inside the retainer. This can result in the rocker riding on the retainer instead of the pad. Check for interference between the rocker and the retainer through a full revolution of the cam (two engine revs). If there is no interference, then you should not have a problem (assuming that your wipe pattern is still okay). yo - As I recall, VE is simply a measure of the amount of air that actually gets drawn into a cylinder divided by the cylinder's swept volume. For instance, at 100%VE, a cylinder whose swept volume is 1 liter actually draws in 1 liter during it's intake stroke. At 50%VE, that same cylinder would only draw in 0.5 liters. VE is not a single number for an engine - rather, it is a function of RPM (possibly also manifold pressure).

Thanks, guys. The surge tank is integral with the plenum, and includes a summing network across the top of the plenum, for summing the vacuum sources from each cylinder. This also allows the IAC to be integrated into the assembly without any additional hoses. There is another small tank integrated in at the back of the plenum (also connected to the summing network), for supplying vacuum to the booster and other accessories. I plan on summing vacuum sources to a seperate summing network for the MAP sensor and FPR, so that I can keep them isolated from fluctuations from the accessories. Also, this will allow the engine to run with the plenum disconnected (i.e., if I want to sync the TBs). At the inlet, I angle cut a 3" velocity stack to give a smooth transition into the plenum. Since I did the welding in several small steps, I was also able to make sure that the inlet was pointed directly at the pass through point for the intercooler piping, so no S-bends were necessary there. I still need to add a flange for the boost recirculation (blowoff) valve, and some tabs to mount the heat shield to. I have the old exhaust manifold installed for mockup purposes, since I don't have the SFP header back yet. It's getting close...

VE shouldn't change unless the valve lift/timing is changed (possible but not likely). I think you are thinking of specific power output, which probably will go down slightly, due to the added friction.

Just FYI - perhaps you already knew this, but standard steel braided hoses do not have a high enough pressure rating to use with a power steering system - you can get pressure spikes of over 2000psi at full lock. Both Aeroquip and Earl's make special power steering hose and hose ends. This is what you should use.

I'm pretty sure that DOT 3, DOT 4 and DOT 5.1 are compatible - you won't get full performance from the higher grades if they are mixed, though. DOT 5 (silicone) is not compatible with the others, and is generally a bad idea for a performance car. I'm using ATE Blue (DOT 5.1), btw.