Very Low Dyno Numbers
Very Low Dyno Numbers My car is a 2004 GTO, mods are listed in my sig. I recently took off my Patriot stage 2 heads (2.055 1.57 64 cc unmilled) and replaced them with AFR 205's milled to 63 cc. I used Cometic .040 gaskets. My best dyno from Speed inc. was 378 hp and 370 Torque with a locked converter. It seems as though I lost power by switching to the AFR's. The hp and torque were 365/351 with a locked converter. 
Who else is running a Vinci XXX cam with AFR heads? Or even a similar cam to what I'm running? I was told my current heads and cam combonation should yield 400+ hp on torque on an LS1. As far as I know the cam was degreed in properly, and the valves lashed in correctly using the acclerated lift Crane 1.8 rockers. On a side note, the car does feel stronger now than what it was, but the peak numbers don't make any sense. Also this time around I had another place do the tuning, so it was a different dyno. Also they said the part throttle settings (VE table) were way out. Opinions anyone?
Thanks,
Matt
Who else is running a Vinci XXX cam with AFR heads? Or even a similar cam to what I'm running? I was told my current heads and cam combonation should yield 400+ hp on torque on an LS1. As far as I know the cam was degreed in properly, and the valves lashed in correctly using the acclerated lift Crane 1.8 rockers. On a side note, the car does feel stronger now than what it was, but the peak numbers don't make any sense. Also this time around I had another place do the tuning, so it was a different dyno. Also they said the part throttle settings (VE table) were way out. Opinions anyone?Thanks,
Matt
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How many 1.8 rocker arms installs have caused valvefloat in the past?
(Do a search....answer is alot). IMO its better to put a little more lift in the lobe and run a lower ratio rocker but of course you will get varied opinions on that (as well as just about everything else).
I touched on this with you already on the GTO board in addition to the fact different dynos yield different numbers.
Humor me and swap back to your stockers and pay attention to the proper pushrod length as well. Also I wish you were running our 8019 springs which I have done ALOT of testing proving out on the dyno and am convinced are the best springs from a valvefloat/power producing perspective. Nothing has shown me better results and Ive tested quite a few different valve spring combinations.
Show these guys the gragh overlays as well (even though different dyno). The area under the curve gains are substantial and they can also see how the power goes flat from 5500 on (telltale signs of valve control related issues).
Tony M.
(Do a search....answer is alot). IMO its better to put a little more lift in the lobe and run a lower ratio rocker but of course you will get varied opinions on that (as well as just about everything else).
I touched on this with you already on the GTO board in addition to the fact different dynos yield different numbers.
Humor me and swap back to your stockers and pay attention to the proper pushrod length as well. Also I wish you were running our 8019 springs which I have done ALOT of testing proving out on the dyno and am convinced are the best springs from a valvefloat/power producing perspective. Nothing has shown me better results and Ive tested quite a few different valve spring combinations.
Show these guys the gragh overlays as well (even though different dyno). The area under the curve gains are substantial and they can also see how the power goes flat from 5500 on (telltale signs of valve control related issues).
Tony M.
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