Comptech s/c issues
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From: Austin
Originally Posted by WashabiS2K,Mar 11 2008, 05:31 PM
did you change your spark plugs? when i went to go dyno-tune mine, my first pass was a solid 283 whp, and then on my 2nd pass, it dropped down to 170whp. My tuner already knew exactly what the problem was. He pulled out my spark plugs, and just as expected, they were fried. I completely forgot that I had brought new spark plugs to change before the tune 
luckily, my tuner said it was no problem and he helped me swap out the burnt plugs with 1-step-colder range spark plugs 
my third pass jumped right back up to 288whp, no tuning at all,. just the change of spark plug. 
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From: Austin
Originally Posted by Spec_Ops2087,Mar 11 2008, 09:13 PM
belt tight? Do you have a boost gauge or have you plugged it into the dynos computer to make sure you are in fact boosting 5psi?
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From: Mesa
Your AFR is going rich just prior to VTEC and then lean because there is a boost pressure drop just after VTEC. The reason is because there is a huge increase in volumetric efficiency once the engine is in VTEC. As your boost drops so does your fuel pressure at the FPR - even though the engine actually needs more fuel in VTEC at a lower boost pressure.
This is a significant drawback to FPR tuning.
Check for leaks on the charge side of the SC. Is there a BOV (could be leaking or stuck partially open). Other thing to consider is that you dyno'd at 170 on that dyno pre-SC and 235 post SC. This is a 48% increase in WHP. IIRC - most cars that dyno at 195-200 NA WHP end up with about 285-290 WHP (about 48% increase in WHP). Pretty close when you compare the percent gain based on NA baseline WHP
This is a significant drawback to FPR tuning.
Check for leaks on the charge side of the SC. Is there a BOV (could be leaking or stuck partially open). Other thing to consider is that you dyno'd at 170 on that dyno pre-SC and 235 post SC. This is a 48% increase in WHP. IIRC - most cars that dyno at 195-200 NA WHP end up with about 285-290 WHP (about 48% increase in WHP). Pretty close when you compare the percent gain based on NA baseline WHP
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From: SLC, UT
You dyno'd low to begin with...this may indicate that your motor was unhealthy prior to the installation or it may simply indicate that this dyno is extremely conservative (unlikely, especially since it's not a Mustang dyno).Something had you down on power prior to the installation of the CTSC. What?
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From: Austin
[QUOTE=CourageOO7,Mar 11 2008, 10:32 PM] You dyno'd low to begin with...this may indicate that your motor was unhealthy prior to the installation or it may simply indicate that this dyno is extremely conservative (unlikely, especially since it's not a Mustang dyno).
Something had you down on power prior to the installation of the CTSC.
You dyno'd low to begin with...this may indicate that your motor was unhealthy prior to the installation or it may simply indicate that this dyno is extremely conservative (unlikely, especially since it's not a Mustang dyno).Something had you down on power prior to the installation of the CTSC.
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From: Mesa
Originally Posted by Sondra S2K,Mar 11 2008, 09:12 PM
That's exactly what we've been trying to figure out. I know of two other S2000s, one an 00 and the other an 03, both supercharged with exactly the same kit and pieces, who dyno at 299 and 311, both gaining 100+ hp from their baselines of 195-199. Something's not right with mine, but we just can't nail down what is wrong. I'm getting very frustrated.
Were both of those cars dyno'd on the same dyno you are on?