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Discussion Starter · #1 ·
Huge torque gains that fall off after 3,750rpms. 669.7ft/lb & 627.3hp.
I've been searching to see if anyone else ran into a similar situation but I've yet to see such a large variance between tq/hp. I figured with headers/catless x-pipe and cutouts that TQ would be lower. Would that explain the fall off? Anything to be concerned about tuning related?

'12 6m Coupe
Airraid
2.4" Upper (stock lower)
Flex Fuel sensor
FIC 1000cc
TSP full catless system w/QTP cutouts open
Low mount HX & expansion tank
MM Catch Can

DYNOmite dyno
Pump 93 on the first sheet
50% E on the 2nd

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Discussion Starter · #6 ·
Your torque is peaking at 3750 and rapidly declining because there is a significant restriction with the stock cam and heads. A properly spec cam should flatten out you torque curve and heads will allow you to make more power in the mid to upper range. You can probably upgrade the lower pulley to a 8.66 or 9.06 while doing the cam upgrade as well.
H/C are next on the list (after putting a tire on it). The tuner (big LS/Vette shop) said my next move should be cam, valve springs and ported SC/Snout. I asked about porting the stock heads and he said it isn't necessary at that level which seems contrary to most.
 

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Discussion Starter · #10 ·
Stock cylinder heads flow about 290 cfm on the bench.

That flow is capable of producing about 676 NA fwHP.
A bit more with a Roots Blower. . Depending.:eek:

And since HP is directly connected to engine rpm / piston speed,
that could be why the HP Number was low.
Your engineering mind is truly impressive.

I'm just curious why he let out early. You'd think with 1000cc injectors it wouldn't be maxing them out and the stock pump should be good for more.
 

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Discussion Starter · #11 ·
If your swapping the cam, then porting the heads will complement the cam very well. It greatly increases the efficiency of the engine across the entire usable rpm range and lowers iat2 temps.


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It's one of those might as well things. What's killing me is they're having a Black Friday special- Free head porting with cam package.

Unfortunately, I'm getting married this weekend and that whole thing snowballed price wise. She's lucky she's a good woman.
 

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Discussion Starter · #12 ·
So he is happy that the torque peaked so low then..;)

And one should first target a HP,
then flow the heads,
then determine engine shift point,
then choose the 'appropriate' camshaft. . . .

As cylinder head goes up, the appropriate camshaft requirements becomes smaller.

With too small a head, generally you can't increase the valve lift much,
so one tends to add unnecessary duration.
Ah! So basically putting me in a situation where I'll need to do a cam. He mentioned the B3.

When the time comes I'll do some digging around the forum, figure out realistic goals etc..

My 55g drum arrived today. The driving 38 miles each way for E is already getting old.
 
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