running_cold924

mike- i've read about your dead knock sensor. Have you tried installing a knock counter just to see if it would read anything? may be interesting to find out or help verify its dead. i actually was hopeing for some better results because I sort of have a setup like yours, just not the turbo yet...

Bri Bro

Not only does it no build HP past 5K, the boost doesn't max until a little before 5K. I think you need to fix your exhaust leaks.

MM951

I don't know why the dyno shows the boost plot like that - I have 18 psi by 3,700 rpm according to my VDO boost gauge. I agree that I have exhaust leaks, but nothing too serious. I spent a bunch of money and time replacing the headers, crossover, crush rings, etc a while ago in an attempt to fix it, but it had minimal impact. The only spot that even leaves evidence of a leak in the whole system is the #4 exhaust header flange at the cylinder head...

V2Rocket

from 4000-6500 you ran an AFR under 11:1 in each run...maybe a little too rich for power?

Bri Bro

18psi by 3700 sounds a lot better. Here is a dyno I dug up with a 60 hifi. Looks a tad bit better in all areas.
https://rennlist.com/forums/1304914-post18.html

what exhaust are you running and do you have a cat? Did you check your downpipe from the turbo for a collapse of the interliner?

Van

Here's the comparison with my car. I have the KKK 26/8, stock AFM, Lindsey boost enhancer, stock KLR chip, Russell's "booster" DME chip, and an open exhaust.

Van

P.s. remember that those boost values don't mean anything... I haven't figured out what voltage values to enter into the software to have it be actual PSI. But, what it does show, is relative boost. Mike's making a bit more boost pressure than me (I only have the stock gauge, but I probably peak at 14 PSI (because of the LBE) and then it drops down to 11 PSI or so.

His AFR is much richer than mine... he's around 10:1, and I'm almost 12:1.

I wish we could map ignition timing...

Bri Bro

Looks like you meed to shift at 4800 rpm to stay in the power band. I was wondering what is your open exhaust, stock pipe with no cat and muffler?

Rogue_Ant

Looks like your ~80hp low to me... Find out what the problem is.

Van

I don't mean to take Mike's thread off topic... But I have a custom exhaust that's 3", going to 3.5", going to 4".

MM951

Van and I think so too, I will be checking some of the sensors again...

Don't tease me with a dyno graph like that .! That is pretty much what I'm shooting for. Sad that I am making ~70whp less and at much lower rpm..

I am running a test pipe (2.5"), Borla catback (2.5"), and a stock downpipe, which I have not checked for a collapased inner section, but when I put the car together 2 years ago it looked fine. Probably worth checking again... I have been considering a 3" exhaust for some time, but I like the sound (fairly quiet, all spool) of my car as it is now. Still, if it would mean a significant bump in tq/hp I'll do it.

Thanks for that graph, it sure was a PITA trying to compare your car vs. mine by switching back and forth. Your car really seems to have more low end and essentially the same tq. One thing that is surprising to me is that it is showing I have boost before you, yet you have more tq at lower rpm.. Sometimes the car does feel like the boost is like boost level x .75 if you know what I mean

I think Van has a stock downpipe, 3" section, then 3.5", then 4" at the end, with no cat, but I may be wrong.

Yep. I'm really hoping I can pick up this lost power easily/cheaply. Once I get home from work I am gonna spend some quality time with a multimeter and the DME/KLR harness checking sensors etc.

333pg333

Van, so you have a 4" exhaust with a stock turbo do you not? Did you get any logs of the differences?

Just a quick OT while you dyno dudes are around. The dyno we use down here is a Dyno Dynamics and for some reason it runs the torque in Lbs not foot pounds. Does anyone know how to convert? My most recent pull showed about 1130lbs torque. Any ideas?

Back to program...sorry....

toddk911

With a bad knock sensor and the power gone up top, could there be timing getting pulled out?

Van

I put that exhaust on many years ago - and never did any before or after dyno runs with it. But, I remember feeling a "noticeable increase" after putting it on.

Bri Bro

The power and torque curves shouls cross at 5250 rpm. If you trust the HP number, you can calculate the torque.

HP = Torque x RPM ÷ 5252

So at 5250 RPMs
HP= Torque