I have a 94' ls, in stock form I ran 16.5. About 50k miles later ( 154k now) and a few bolt ons (DC 4-2-1, AEm cold air, UR under drive pulleys and a race cat "Landspeed") i ran an awsome 17.2 . Just a couple of more details to add, I had installed a Fuel pressure regulator boosting pressure from 34 psi to 39 psi. I did'nt get in 4th gear til' about 150-200 feet to the finish line. My first check will be compression, but I dont think thats it , it's a honda. If you have any logical conclusions i appreciate it.

 

Tune-up, drop the fuel pressure, you might have rasied too much. Tire pressure. Compression test give good insight.

 

sounds like you raised the fuel pressure too much. go to the track and test it at different psi.

 

Check plugs, cap/rotor, and lower fuel pressure.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dirtman &raquo;</TD></TR><TR><TD CLASS="quote">I have a 94' ls, in stock form I ran 16.5. About 50k miles later ( 154k now) and a few bolt ons (DC 4-2-1, AEm cold air, UR under drive pulleys and a race cat "Landspeed") i ran an awsome 17.2 .
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OK, this may sound obvious, but were both slips at the same..

-temperature
-humidity
-track
-tire pressure (or tires for that matter)
-car weight (did you add some monster heavy sub box?)
-did you eat nothing but burritos for a full year and put on 200lbs?
-was the engine in the same state of tune (plugs, valve adjustment...)