Engine/Transmission (1994 - 1998) Too Much Turbo ??

[TGroves]

well got my truck back together after a blown head gasket ,,, studed and fire ringed ,, new turbo and manifold and down pipe ,, "sps66 ",, got the head torqued three times and took it out and got on it ,,,, well the truck feels like a slug see sig for other items done ,,,, i can see 50 psi but just does not feel like it pulls???? any help would be great or do i need to put more money in it :-laf

 

[9 Lives]

I would go easy on it after a new head gasket. I would at least wait until I had done all my re torquing before give her all she has.

 

[zstroken]

I agree I would run it thru a few heat cycles, and retorques before you give it the go. Is it just puking black smoke? If so you may need some AFC tweaks.

 

[TGroves]

yep, lots of black smoke ,, or should i put my # 5 plate and take the 0 out????

 

[zstroken]

Adjust the AFC to limit some of the black smoke, too much fuel will impede spool up.

 

[TGroves]

i changed the afc spring to a soft one should i change it back to stock ??

 

[zstroken]

On a bigger turbo like that you want to set the AFC where the charger starts to light. On the SPS I would say about 10-15 psi. I set mine to move fully with 30 psi. I had a super tight convertor. Also I imagine I had quite a bit more fuel. I ran a zero plate, but if I had a stock plate to grind on I would run a 100 plate. If you set the AFC right though it will function better than a plate. The AFC allows fuel based off of boost, the plate goes off of RPM.

 

[mclunas]

Adjust the AFC to limit some of the black smoke, too much fuel will impede spool up.

what can i do with mine too keep some of the fuel out before the charger lights. . ive noticed that it spools a lot quicker if i turn my comp box off but then i dont have near the power. is there any way to limit it without having to turn box on and off...

 

[EHarvey]

i changed the afc spring to a soft one should i change it back to stock ??

i have a similar signature and i also had the sps66 i know it takes a little bit to spool it up, but once it goes it should pull really hard. I changed my cam to help with spooling issues. I had my timing a 20 deg but i think it would make things worse. Stick with playing around with the afc. Sounds like theres way to much fuel on the bottom and with that big of a turbo if you cant get it to spool it wil feel like a slug. good luck keep us posted

 

[TGroves]

well got home moved the afc housing to the middle and turn the strar wheel one whole turn because it was all the way forward and that made a huge differance in power truck feel like it gained a other 100 horse ,,, thanks for the help "zstroken"

 

[TGroves]

well got the afc adjusted and it runs better... . i got on it and when it hit 4th gear and the troque converter locked up the truck bucked and feel like it was hopping ??? but i was no lossing traction ???? got off the gass (diesel) and it stoped and all is fine... ????

 

[AndrewKing]

You possibly caused the lockup to shudder (slip) due all the power... . May be time for a better converter... . well at least it's a good excuse for one!

 

[TGroves]

wow ,, only got about 2000 miles on my suncoast transmission now ??? and its all billet to

 

[Forrest Nearing]

after you retorque a few times, give it a few more degrees of timing, it'll rip a lot harder on the big end (which is where that turbo shines anyhow

 

[TGroves]

thanks , we are to put the timing at 20 this weekend ,, i was thinking of sending the turbo back and down sizing?

 

[Forrest Nearing]

I think you'll be VERY happy if you go with a 62mm compressor vs. the 66...



I ran a silver 66 for a week, and it pulled HARD in the 3000+ range, but it didn't really get started till just over 2000rpm. I'm betting an sps66 would light off a little sooner.



it was fun, but just not as drivable overall as the sps62, so I put the 62 back on it and sold the 66.



this was with a 6sp, I would imagine it would be pretty smokey/laggy with an automatic unless you were running a full manual valve body and a floor shifter

 

[zstroken]

I think 20 might be a tick much on the street, I would say 18 would be a little better suited. The higher the timing the slower the initial spool will be.

 

[TGroves]

well ,we will be in goshen saturday for the truck pulls and go to orp (irp) tuesday night before the big event . . hope i can work the bugs out ... i also ordered some ddp 4 injectors today i'm going to try that before i really send the turbo back ... talk to brandon at II and he said i would have to buy a whole nother turbo and would have to sell this sps66 ???? i heard II could change the housing for a price ??