fstrnyou

I have about 2k miles on a rebuilt ported motor from Atkins. also have custom TID and gutted precat. For some reason, my car isn't nearly as fast as it should be. I know i'm making more boost but it just doesn't pull any harder than when it was stock. as a matter of fact, i was only .02 seconds quicker in the 1/4 compared to when my car was stock. i'm baffled that i'm not seeing any results. the porting is claiming to increase hp by 25%. add the intake and "high flow" cat and i should be pushing more than 230hp, at the motor of course.

andrew lohaus

maybe it needs to be broken in. checked the coils, grounds, and all that other good stuff that can sapp power without being very obvious?

JackoliciousLegs

jack = noob... how do you check grounds?

The BIg j

i have the same problem. i have an 86 n/a and it is not as fast sa it should be. i have been told this by countless people.

Molotovman

iTrader: (49)

Check you vacuum lines, make sure theyre all where theyre supposed to be.

fstrnyou

nearly all vac lines were replaced. i did remove the acv/airpump and vacuum line spider web under the manifold. the only vac. lines that i kept were the ones attached to the throttle body(secondary lockout mechanism), and the oil injector vac lines. i believe all other lines were replaced. i had planned on adding two more grounds made 4GA power wire but haven't gotten around to it. also, turbo spins freely.

88IntegraLS

Have you tuned the fuel map for the increased airflow due to the ports? How about to compensate for the Walbro pump?

You can go faster in the 1/4 mile by changing those stock TII wheels for something in the 15lb range.

fstrnyou

Umm. The AFM changes the fuel map for the increased flow. The fuel pressure regulator compesates for the larger fuel pump.

88IntegraLS

Okay, I understand that line of thinking. It's not the prevailing mindset on this board concerning turbo II's with mods, but it's your car so I just thought I would give my perspective. Even NA cars with just intake and exhaust mods have been known to pick up 10 rwhp on a dyno if they have an S-AFC that has been tuned (forum member wozoom for one).

Good luck.

fstrnyou

I didn't intend to come off like an ***. I just was under the impression that the AFM controlled fuel delivery amounts and the FPR controlled the fuel pressure in the rails.

SureShot

Mine was slow until I discovered the secondary throttle was not opening at all.

I removed the dashpot, cam, & holdoff diaphragm, and wired the secondary open.
The empty vac nipple in the TB made a good boost gauge source.

Aaron Cake

iTrader: (1)

My first though is as SureShot mentioned. The seconary throttle plates could be stuck closed.

After that, it's important to do a full tuneup. With that new of an engine, the plugs are probably fouled. Compression test would be a good start, but it can take quite a while for rebuilt engines with used housings to build up compression to what it should be. So I'd wait a few thousand more miles...

Sideways7

iTrader: (7)

So are you saying that plugs will foul faster on a newly rebuilt engine?

Aaron Cake

iTrader: (1)

Yep, until the compression builds up and all the seals break in.

fstrnyou

Well, I am getting another throttle body from another member on this forum. I'm thinking of doing a little porting and taking the secondary lockout plates out. Not sure if I should take the shaft out as well as this would require plugging some holes.

You know, I never would have thought of that. I was just wondering how I'm gonna plug that port without something blowing back off under boost. I have a 4-way connector near the pressure sensor coming from the manifold and splitting 3 ways, 1 to boost guage, 1 to pressure sensor, and 1 to BOV.

Yah, since compression is low on newly rebuilt motors, combustion isn't at its peak efficiency. I haven't done a compression check or looked at the plugs since I put the motor in. Sounds like it may be a good idea to do a little investigating.

Aaron Cake

iTrader: (1)

If you have not seen the plugs since you put the engine in, they are bad.

fstrnyou

Last week, I lifted the upper manifold/TB assemply and removed the lockout plates but left the shaft. And runs a little better but still not what I expect. Well, I checked the plugs this morning. They "looked" ok but I'm no expert in diagnosing a car based on spark plugs. I let the motor warm up until the needle was a little into the normal range. I went driving around to warm the motor more. I did notice and have noticed before that when I first leave the parking lot when the motor isn't to full temp but definately warm, that the car pulls very hard. And when shifting into second boost spiked to around 9 or so. But when the motor fully warms up(just less than half way up the guage) it doesn't pull as hard and boost only makes it to 7.5. Is there a reason for this. Maybe someone can shed a little light as to the reasoning behind the lower boost when the motor is hot. Oh, also ran a 4GA ground from the front of the water pump to the passenger shock tower.

Also...checked the rear compression when i got back from warming the motor. reads about 98-99. is that low for haveing around 3K on the motor? or am i right on schedule? very very rarely will the motor flood itself after driving for a while. went to zaxby's last night and when i went to leave, it wouldn't start. so i unplugged the fuel pump relay under the dash let it crank and fire up until it ran out of gas then plugged the relay back in and it fired up and i drove off. again...very rarely does it do this. is 99 pounds low enough to cause this. the fuel injectors were cleaned by RC when i installed the motor. Thanks for your help guys. I really appreciate it. And I look forward to helping you one day.

Craig

88IntegraLS

Part of the reason it may pull harder when cold is because it hasn't had a chance to heat soak the intake manifold and IC. Just about every car I have driven has been that way. As for the boost problem, I wouldn't know. I'm boostless!

fstrnyou

a friend of mine said the same thing. and it's possible but the intercooler isn't doing anything when i'm in first and second gear anyways. so, even if it wasn't heat soaked, it's not acting like an intercooler. oh, and my car idles for about 6-10 minutes before it gets into the normal range. so i'd figure that the intercooler might be hot. oh well. was just hoping it was a bad sensor or something that i could replace to make it faster. i know, get a FMIC. don't have the money...