I took a video of a quick WOT drive. My tune is pretty well dialed in and I'm only running 8psi. I just wedged the camera in the headrest, but the quality ended up being pretty nice. http://www.youtube.com/watch?v=PwHnUIigNIg

Cool man, you can hear the turbo pretty good on the cam, must be even better in person. I like your gauge panel also.

Yeah, you can definitely hear the turbo since I have the downpipe end right below the engine compartment. When I run the exhaust to the rear and through mufflers, I can only hear the bov between shifts. Here's another vid of a walk-a-round of the car.

http://www.youtube.com/watch?v=PdrdX-Jp1BM

have you ever drag raced on a track. just curious what times it runs. is that about a 70mm turbo?

I've never been to the strip or had it dynoed since I've changed to tpi. I keep on telling myself that I'll go when I eliminate every issue, but that never seems to happen.

The turbo is an older unit that I can't find any info on. I measured the compressor wheel, but I forget what it was. I'm replacing the white pvc intake with black pvc tubing (since everyone seems to comment on the sewer pipe), and I'll retake the measurements then.

I switched over the intake tubing and I measured the compressor wheel. This is what I got:

Inducer: 2-5/16" (59mm)
Exducer: 3-3/8" (86mm)

Here is a pic:



It reaches full boost at 3800rpm and here's a recent datalog which shows it:

thing looks like it rips

i am curious what your torque curve looks like with that TPI

having a turbo should make the mid-range hump distinctive more than usual!

24* @ 7psi good choice for timing, Do you have an EGT hooked up? Im curious what the powerband would do at 20* vs 25*
Im assuming you run on 93 octane pump.

Thanks Kingtal0n, your 'recipe for 500hp, 22mpg' post was an inspiration for me when I was planning my build.

It's a lot of fun to drive around on the street with just 7-8psi. I do not have an EGT sensor. Most of my tuning is performed with the datalogger, wideband O2, and knock sensor (even though it has a false knock around peak torque). I always fill up with 93 octane and keep the timing conservative.

I doubt I will make it to a track this year, but I will definitely have it on the dyno before it gets put away for the winter. My goal is to hit 600rwhp with more boost.

That wheel is very old technology. Even a 59mm BW extended tip, Holset HX, Garrett GT comp. wheel would not hit 600 RWHP. That wheel you have is good for probably up to 500 FWHP (not RWHP) at best.

Nice setup.. and 24 degrees of timing! I need to get an intercooler on mine I guess. I'm around 13-15 degrees total at 9 psi, but I have 9.3:1 compression. It really seems like I could get away with more timing than I am but I've had detonation several times with anything higher.

Ahh I just realized you also have aluminum heads, so that is supposed to help a bit too on detonation.

Did you leave your IAT sensor in the stock location in the plenum or move it out to the charge pipe? It seems like once the upper intake gets heat soaked, the sensor stays at 130+ degrees even though the air is not that hot.

What manifold setup did you use for the turbo?

junkcltr, the person who sold me the turbo said it was rated for 600hp. But, like you mentioned, it has a smaller wheel than what similar guys making the big #'s are using. I'll be happy just finding how much power I can make from this setup.

ZZ3Astro, I run 24° at max torque and increase to 26° up to redline. I've even had it up to 28° at 7-8psi without detonation. The combination of 8.5:1 compression, alum heads, intercooler, and 93 octane allows me to run a bit higher I guess.

Also, the IAT sensor is in the manifold still. I do see heat soak, but even then the temps stay under 100° after a boost run. I'll eventually move it just so it will be more accurate, but since the ecu can't change timing based on intake temps anyways, it's not that critical.

chevymec, the turbo manifolds were fabricated from C4 corvette manifolds. I used 2-1/2” mandrel bends to form the crossover and inserted a slip joint between the two sides.

Thanks for remembering! I am on to 500WHP with 30MPG these days haha!

Your knock around peak torque could be real. It depends on the VE around peak, since you have TPI I would expect it to be a serious peak! Have you tried dialing the timing back to about 15~ through peak torque to see if your knock goes away? Its worth a try.

Remember that timing doesnt make power, it only lights your mixture. Yes if you light off too late it makes less power, but thats why I asked about EGT because you will see your power turn to EGT temps and they will rocket up. The trick with timing is using JUST ENOUGH- not using AS MUCH AS POSSIBLE. You wont make an extra 10horsepower no matter how much extra timing you add, you only move closer and closer to engine damaging pre-ignition.

If you have access to a dyno you can test, simply pull back the timing and see if it makes identical power, sometimes the torque gets even smoother (use ZERO SMOOTHING on a dynojet).

Remember that the ECU timing is constant. It doesnt know when the engine is extra hot, or cold. For instance when you first start the car in the morning and drive it around for 30 minutes then boost it- yes it runs great and all is perfect with your timing. 2 hours later you do it again- and the engine is hotter, so you have a hair too much timing there. You wont hear it, you wont see it, but that doesnt mean it isnt eating away at your deck and pistons. car will still run the same, or seem to.

Thanks for remembering! I am on to 500WHP with 30MPG these days haha!

Your knock around peak torque could be real. It depends on the VE around peak, since you have TPI I would expect it to be a serious peak! Have you tried dialing the timing back to about 15~ through peak torque to see if your knock goes away? Its worth a try.

Remember that timing doesnt make power, it only lights your mixture. Yes if you light off too late it makes less power, but thats why I asked about EGT because you will see your power turn to EGT temps and they will rocket up. The trick with timing is using JUST ENOUGH- not using AS MUCH AS POSSIBLE. You wont make an extra 10horsepower no matter how much extra timing you add, you only move closer and closer to engine damaging pre-ignition.

If you have access to a dyno you can test, simply pull back the timing and see if it makes identical power, sometimes the torque gets even smoother (use ZERO SMOOTHING on a dynojet).

Remember that the ECU timing is constant. It doesnt know when the engine is extra hot, or cold. For instance when you first start the car in the morning and drive it around for 30 minutes then boost it- yes it runs great and all is perfect with your timing. 2 hours later you do it again- and the engine is hotter, intercooler is heat soaked, engine bay is hot, everything is higher temp to the max, so you may have a hair too much timing there. You wont hear it, you wont see it, but that doesnt mean it isnt eating away at your deck and pistons. car will still run the same, or seem to.

Huh... do you have a better picture of passenger side manifold, especially around the front port?

Not sure if these help you, but they're all I got at the moment.

Not really, but thanks anyway... I've done a few "manifolds" at this point and always end up compromising one way another, usually either where the crossover enters (I prefer to run it through the stock location and back up toward the middle 2 ports), the middle 2 ports or where that side meets the flange, I was hoping that you came up with something clever avoiding any awkward angles, packaging issues or spark plug issues.

I hope to try again this winter, but this time I've decided that I'm going to get either a 3.5 or 4" downpipe through there and still keep the air-conditioning (the "project car" that I bought was more complete than I wanted, someone even converted the AC to the new stuff, so it would be a shame to ax it...), i may spend some extra $$ on a few extra v-band flanges and make a small section of the downpipe easily removable and then not worry about spark plug access as much.

Actually, I'm curious, why did you run #8 up and back down? I've run that one down and tight against the block which without an AC heaterbox gives you miles of room for a downpipe and to get at the plugs.

I found a couple more pics at home that shows the manifold setup a little better:





The #8 tube going up instead of down was my brother's idea. I was just learning to weld at the time, so I had him weld up the manifolds for me. It looks funny, but when the manifolds and downpipe are installed, the spark plugs are fairly easy to get to. The driver's side plugs are extremely easy and about a five minute job, compared to around 20min for the passenger side.

Kingtal0n, I didn't forget about your advice. Last week I performed a boost leak test on the car, since I wasn't able to increase boost past 7-8psi with the mbc. I took the coupler off the turbo and used fitting to hook it up to 10psi from an air compressor. I found a few big leaks including a hole in the intercooler, in the tube where my bov connects, around the throttle body coupler, and through the throttle shaft. I welded the first two up and used a t-bolt clamp instead of a worm gear clamp to tighten the TB coupler. I plan on replacing the TB unit soon which hopefully with eliminate the last leak. Doing all of this, I am now making 10psi instead of 7-8psi, and I made another datalog to show this.



I took your advice to lower the spark more around peak torque and I think that did the trick. I set it to 19 at 160kpa and now it no longer pulls timing in that area. It feels just as strong, actually a lot stronger with the couple psi increase. Thanks for your help.