Engine/Transmission (1994 - 1998) Question for 12V aftermarket turbo users...

[TravisG]

Running the thicker gasket lowers your compression a little bit which will cause you to lose a little bit on the bottom end but you make up for it in the upper rpm's. Maybe Jim will step in here and correct me if I am wrong.



Right now I am running 18 degrees of timing.

 

[Jim Fulmer]

Running the thicker gasket lowers your compression a little bit which will cause you to lose a little bit on the bottom end but you make up for it in the upper rpm's. Maybe Jim will step in here and correct me if I am wrong.



It's makes just a tad bit of difference but not that much. When you O-Ring you head there going to have to take some material off to make it flat unless it different than any head I've ever heard of.



Typically . 006-. 010 so when you go with a . 020 over gasket your not really changing that much, but you do need to go with at least a . 010 over gasket to put it back to stock specs and keep the piston to valve clearance correct for the cam your going to install later



Big Compression changes are like mine... . minus 2 points via a piston shave job. It doesn't seem to be an issue of any kind as long as the grids aren't temperamental like mine..... work to be done here.



Jim

 

[Bandit1]

my compression is 1. 5-2pts lower also, i cant remember exactly. i run 20 degrees of timing. we opted to lower compression so i could runmore timing and fuel and not worry about HG issues, i really shouldnt anyway firerings with 14mm studs. that thing isnt going anywhere. starts up fine in the cold.

 

[HEMI®Dart]

I knida figured it was something simple like that, If I were to be able to clock it enough it probably would have saved me some time today.

Anyway I got it buttoned up this PM and took it out for a burn and it runs great. No lag and most boost I seen before I got scared and let up off the go pedal a little was in the 46psi range. Probably coulda got 50 but stock HG/No studs :{

Now the big question is, WHATS NEXT???

Signal,



I lengthened the wastegate actuator rod so it starts to open at 40 PSI. I also replaced the adjustable boost elbow (the elbow in the compressor housing w/ the setscrew) with a straight through elbow.



I have the OEM headgasket and bolts too.

 

[Signal73]

Ill have to tinker with that to see if I can get it down a little. Watching the guages, I felt I could have easily seen 50lbs considering how much pedal I had to go when I was at 46.

Hardware store sell those elbows straight through? 1/8 NPT looks like to me?

 

[HEMI®Dart]

Home Dummies will have the 90° elbow. I believe it's a 1/8 NPT.



I would try that for now. You won't be able to get the the actuator.

 

[BradyWilliams]

RE: Two new turbos released

The Super Phat Shaft 64 has been out for a few weeks and is a very good upgrade to a second gen. truck. Quick spooling to help with the bottom end smoke and yet this turbo will produce big hp results. The Super Phat Shaft 62 is the perfect turbo for pulling heavy loads. The large turbine side drops drive pressure and yet the new designed 62mm with extended blades delivers a lot of air and will support well in to the 500hp range. The comp map shows that this turbo will be good to very high pressures. This turbo has NO comp surge and spool up is very impressive. Thanks

 

[Signal73]

Thanks Bill

 

[Jim Fulmer]

I've already tuned and tested a 12V with a 64/14. The run down on the mods are. A II tweaked 215 pump with a #6 plate and 4K's, stock DV's, Stock 370 and a mildly built auto. The truck is more than just a little impressive and even at 47 psi (wastegate wide open) had allot of fuel to clean up. The turbo spools really good at light throttle and during normal driving but is instantaneous at WOT.



Jim