1990 GTU single turbo dyno tuned
 

Well, I was finally able to get the car tuned on friday 2.20.09. I have a 90 gtu with a turbo 2 motor, MP T70 with Garret internals, 850 and 1600 inj, Weldon 600a, Microtech Mt4, 2 msd hi6al, 2 blaster coils, ebay hks style wastegate, HKS blow off and a single side exhaust, fmic. On the dyno, the gremlins came out. I had to replace the Weldon with a new one due to voltage issues from the pump ( only reading 10.1v) and the spring inside the wastegate was toast (replaced with a new spring) before these corrections the car was making 308 rwhp going up and down with major flactuations in the readings. After the corrections, everything evened out and 420.07 rwhp and 332.05 tq was able to be made at 15 psi. Currently with the MT4, I cannot go past 2 bar which is another issue. I honestly am pretty happy with the results. I do not know how to scan the dyno sheets, i have a few. I am truly contemplating upgrading a few parts and seeing how much more the car will produce...:scratch:

This was tuned on 93 pump gas.

wow great numbers, congrats.

sounds good, I was doing 385rwhp around 13.5psi. With the same turbo a few years back.

Thanks guys! I am thinking about opening the motor back up, replacing the factory seals with RA seals and replacing the MT4 with an lt10 with x4. I am really hoping to be in the 500+ rwhp club on my daily driver. The car is going out to the track this week to see how she does???:scratch:

congrats,very good numbers

running a distributor? i love it! now did you lock the timing or just do a global retard and let it advance to x amount of degrees?

great numbers btw!

It's "welded" but once I go with the LT10, I can get rid of that and a few other items!:icon_tup: Thanks guys!

Well, it seems that the GTU rear end could not hold the 420 rwhp. I did not launch the car just rolled into it, nope, it's gone. Iam going tobe opening the motor now and put in the RA Super Seals and other related items. I was surprised the factory seals did so well. I am also going to be ordering the lt10 inthe quest for 500+ rwhp, WOOOOHOOOO:Wconfused

man i would just keep the distributor ;) simplicity at it's best and you're getting more spark now with those msd's on the dizzy than you will using the microtech's ignition system.

The only thing I don't like is the fact of the MT4 only being good for 2 bar. I was hoping to build the motor and go high 20's maybe 30#?? I spoke to the mechanic and it seems that the differential mount is the culprit of my recent woes. At least I hope. He will be checking in the morning what needs replacing.

can't you send it to microtech and get the 3bar installed? i've tuned a few microtechs and i'm not happy with how it's setup. the cars did well but i feel i could have gotten more with a Haltech in it's place :)

What was wrong with the wastegate spring?

You could squeeze the spring with your 2 fingers.

nice numbers man! Looks like these t70's are getting some pretty good numbers! These turbos make some damn good power when your not running at 9.6:1 afr :lol: Anyways that hp at 15psi is no joke! Congrats!

Thanks! I'm looking at the dyno sheet and from 5,750 rpm the car is making around 290 rwhp. At 6,500 rpm the car is now producing the 420 rwhp and 330.86 #tq. I like the way the boost comes in on this car. it was conservatively tuned due to the mt4 issue and factory seals. I am looking at correcting those soon as well as the rear end. I had the MP t70 rebuilt by Mike Turbo with all Garret internals, recently.

Nice! I've heard nothing but damn good things about mike turbo. By chance what did that cost you?

The rebuild was $350 but I had to have the back housing machined to fit the garret internals which was $60 more

Shit that's not bad at all. Looks like I know what I'm doing when this mp takes a dump :)