Engine/Transmission (1994 - 1998) Have a compression question?

[patrobertson]

I just replaced my second head gasket, (first (original) one was bad timing, second was bad torque wrench). Head was checked out and was fine, but was milled . 008 to get a nice smooth surface. First gasket was a . 010 thicker and this second one is . 020 over. Not quite sure why I went so high but I did. The truck is a 96 with 215 pump, #11 plate forward, timing at 15. 5* and some BD 60 hp injectors, that santa brought me. (I think they are 60 hp, not sure I bought them used). Everything works well, I get a little bit more smoke, egts are not a problem, very controlable, It pulls alot smoother, not so ubrupt. But with were I was at I would think I would gain some more power from these new injectors. The motor also seems quieter. The valves are all set right, (ran the motor, warmed it up and checked them again) but it doesn't sound as raspy.

Did I loose some power going with the thicker headgasket? And did it lower the compression enough to cause the motor to run quieter? If I increase my timing some more will help?Now the important part of this whole equation is the old man has a 01 and comp box, DDII's that he got for Christmas and doesn't have the pump wire tapped yet, (He needs a clutch) Well we ran our trucks today and I beat him but not by much, I AM IN TROUBLE HERE GUYS I NEED TECHNICAL HELP!!!!



Thanks a lot guys



Shane

 

[JJW_ND]

Just for Comparison

Shane: My 96 has the same headgasket, with the same . 008 milled, a #11 slide 3/4 forward, factory injectors but timing at 20.



I also get more smoke cold (less compression) but less once warmed up (timing). From what I have been told (no experience here just what I have been told) you lost some HP with the lower compression (about 1/2 a point lower compression) especially on the low end. You also probably dropped a few HP lowering your timing especially on the high end. What was you old timing setting?



On a Dynojet, I went from 346 hp to 329 after the thicker headgasket installed. Only other varibles: 12 months between runs, higher run had no engine fan and stock exhaust housing, lower run had 16cm housing but engine fan installed. I did get back to 356 after increasing the timing (last run and with fan). First two numbers are both with stocking timing.



I really would have rather had the . 010 over gasket but UPS never showed up. Up North here, I now have mucho white smoke (unless I plug in) and it is very stinky. I could do with out that. Never had neither before. Not sure if the thinker gasket provides any benifits below 450hp????



Maybe I am missiterping all the advice I got, but I would think the somewhat higher timing (may 17 or 18 would be better then my 20) would offset the slight loss of compression. The lower compression should help offset the higher cylinder pressures brought on by higher timing.



What we both need is a #10 plate. Then maybe more injectors (me... . yours should really help).



I did not see if you have GSK kit. If you want racing power, the extra RPMs really help. But higher EGTS really show up in upper rpms.



Always want more info... ...



jjw

ND