Hey everyone, so I am curious as to what you guys think. The set up is a GSR block, 81.5mm bore, 12.8:1 cr pistons with a 5cc dome, the block was decked to 0 deck because I lost combustion chamber volume when I had the valve job done, the compression was calculated by the machine shop that built my motor to only be 12:1 so in order to get my CR back up to 13:1ish range I had the block decked. The cams im using are Skunk2 Stage 3s, the machine shop set up the cams to what they called specs from Skunk2, the intake cam is +6 degrees, the exhaust cam was set up to +4 degrees. Is this wayyyyyyyyyy overlapped, im not famaliar to how cam set ups work. The thing im worried about is if I tried to go back and set up the cams where should I start because a big concern would be the block being at 0 deck? Opinions, comments PLEEEEEASE!

 

Trust your builder, and buy race gas.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DonF &raquo;</TD></TR><TR><TD CLASS="quote">Trust your builder, and buy race gas.</TD></TR></TABLE>

Only if you trust that they gave you valve to piston clearence specs measuring at the full 12.7mm of lift that your cams have.

 

Get it on the dyno, the only sure way to tell if that setting works for your application. 2 engines built identically will yeild different settings.

 

It has already been tuned, it made 181hp and 119tq on a Mustang Dyno using 112 octane, took it to the track though and only ran a 13.3 best time with 1.9 60fts, this is not cool to me.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PreStaged12s &raquo;</TD></TR><TR><TD CLASS="quote">Hey everyone, so I am curious as to what you guys think. The set up is a GSR block, 81.5mm bore, 12.8:1 cr pistons with a 5cc dome, the block was decked to 0 deck because I lost combustion chamber volume when I had the valve job done, the compression was calculated by the machine shop that built my motor to only be 12:1 so in order to get my CR back up to 13:1ish range I had the block decked. The cams im using are Skunk2 Stage 3s, the machine shop set up the cams to what they called specs from Skunk2, the intake cam is +6 degrees, the exhaust cam was set up to +4 degrees. Is this wayyyyyyyyyy overlapped, im not famaliar to how cam set ups work. The thing im worried about is if I tried to go back and set up the cams where should I start because a big concern would be the block being at 0 deck? Opinions, comments PLEEEEEASE!</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PreStaged12s &raquo;</TD></TR><TR><TD CLASS="quote">It has already been tuned, it made 181hp and 119tq on a Mustang Dyno using 112 octane, took it to the track though and only ran a 13.3 best time with 1.9 60fts, this is not cool to me.</TD></TR></TABLE>

181 whp and 119 tq seems low for your 1.8L setup. Similar to my Stock B16B with I/H/E and Toda A cams tuned on dyno jet.

Besides the block is your head pnp'd? Headwork is the key to gaining more hp than most other mods, just my .02. You have high compression, large cams, but if the head doesn't flow then no use.

Is it tuned to find the best cam setting or just the a/f tuned for the cam setting provided by the shop.

You may need to test other settings.

 

That does seem a bit low, but I'm not an expert. I have a 1.6 B16A2 that I just tuned @ 170whp 107ft/lbs w/ Skunk2 stage2's, 12:1 CR, OEM Cat., full GReddy exhaust, and 94 octane. Having the GReddy 2.25" header and OEM Cat. really held me back too. Not to brag, just some specs to compare to.

 

you guys are saying 181 seems low but 181 on a Mustang dyno which reads anywhere from 15-20% lower than a Dynojet, so if it was on a dynojet it would have made more than 210hp. The question is more on the cam set up than actual horsepower numbers, +6 and +4, it was my understanding that usually on large cams you only mess with 1 and leave the other, like advance intake +2 and leave the exhaust cam at 0?

 

First of all I don't think most mustang dynos read 15-20% lower, I thought it was more like 5-10% lower. The only way to really tell is to dyno on a dynojet dyno with the same setup and same conditions as you did on the mustang dyno.

Anyway back to your question, when you say the cams are set at +6 and +4 is that overall timing, or is that to compensate for the block being decked? The real answer is to ask the shop that built the motor and find out how they figured 0,0 on the cams. If you are saying the cam gears are set to +6 and +4 that doesn't mean thats the actual amount of advance, first you must find out where the cams are set to 0,0.

 

I am assuming the came gears show +6 and +4 and this is becasue his machine shop degreed the cams in which so many people do not do.

What was your trap speed and the weight of your car on those 13.3 passes. That will give us a better idea of how your engine is performing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by asubennett &raquo;</TD></TR><TR><TD CLASS="quote">I am assuming the came gears show +6 and +4 and this is becasue his machine shop degreed the cams in which so many people do not do.

What was your trap speed and the weight of your car on those 13.3 passes. That will give us a better idea of how your engine is performing. </TD></TR></TABLE>
Well what I had done was I had the cams degreed in to check piston to valve clearance as a result of the block being decked, so I guess a good thing for me to do would be to check with my builder to see if these specs are for 0,0 on the cams or if its +6 and +4.

Vehicle weight is 2170, trap speed was 102-103, like these times were consistent 13.3s with consistent 1.9 60fts, total of 6 runs.