AFR LT4 H/C Dyno #'s.
Thread Starter
Launching!
Joined: Jul 2003
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From: MI
AFR LT4 H/C Dyno #'s. I know . . . LT1 crap probably doesn't belong on an LS1 forum, but CZ28.com doesn't have a dynomometer section . . .
I went to AP Engineering for a dyno tune last Wednesday. Mods are as follows: Stock 350ci bottom end. 195cc AFR LT4 heads (203 cc after porting) flowing 280cfm @ 0.580 lift. Comp Cam from Combination Motorsports, XER lobes, 233/239 at .5, 283/289 advertised .569/.577 110lsa. Hooker longtube headers (no cats), Corsa catback, Ford 9", 17 X 11 wheels w/ 315's out back.
Dyno'd 368rwhp at 6200 rpm and 325rwtq at 5300 rpm on AP's Mustang Dyno. I was pleased with the torque. It would have been nicer to have a little more, but it is flat as a board from about 2500rpm on up. As far as horsepower goes, I know - 368 souunds low (especially on an LS1 forum). And according to the tuner it is low, by at least 12-15hp at the wheels. Based on the graph and some other things, he said I have pretty bad valve float. This really pisses me off - I bought the entire valvetrain from Combination Motorsports - and here's the kicker - it is THEIR cam: Comp only grinds this cam for them. So WTF? They send me springs for their own cam that are inadequate? This cam should be peaking somewhere around 6500-6700 rpm, and the hp/tq curves drop like a stone after 6200.
I figure I'll have to pick up some new springs (or be happy shifting at 6000 - not likely). Seems to me like I should be getting a FREE set from Combination Motorsports, but I'll believe that when I see it. Anyway, assuming I can hit 380-385rwhp after a spring swap, what do these number translate to on a Dynojet? When I put this package together, I was hoping to hit 400rwhp. Kinda disappointed. Anyone know what I could gain from an electric water pump? Pulleys?
I went to AP Engineering for a dyno tune last Wednesday. Mods are as follows: Stock 350ci bottom end. 195cc AFR LT4 heads (203 cc after porting) flowing 280cfm @ 0.580 lift. Comp Cam from Combination Motorsports, XER lobes, 233/239 at .5, 283/289 advertised .569/.577 110lsa. Hooker longtube headers (no cats), Corsa catback, Ford 9", 17 X 11 wheels w/ 315's out back.
Dyno'd 368rwhp at 6200 rpm and 325rwtq at 5300 rpm on AP's Mustang Dyno. I was pleased with the torque. It would have been nicer to have a little more, but it is flat as a board from about 2500rpm on up. As far as horsepower goes, I know - 368 souunds low (especially on an LS1 forum). And according to the tuner it is low, by at least 12-15hp at the wheels. Based on the graph and some other things, he said I have pretty bad valve float. This really pisses me off - I bought the entire valvetrain from Combination Motorsports - and here's the kicker - it is THEIR cam: Comp only grinds this cam for them. So WTF? They send me springs for their own cam that are inadequate? This cam should be peaking somewhere around 6500-6700 rpm, and the hp/tq curves drop like a stone after 6200.
I figure I'll have to pick up some new springs (or be happy shifting at 6000 - not likely). Seems to me like I should be getting a FREE set from Combination Motorsports, but I'll believe that when I see it. Anyway, assuming I can hit 380-385rwhp after a spring swap, what do these number translate to on a Dynojet? When I put this package together, I was hoping to hit 400rwhp. Kinda disappointed. Anyone know what I could gain from an electric water pump? Pulleys?
We hit 404/416 SAE on our final tune on a TEA S3 LT1 headed 383 w/Speed Pro.
The car is an animal to 6800
This was threw a A4/12-bolt 4.10 and makes 400RWTQ from 3200 to 4800
The car has a dead flat hp curve and its making 350RWHP by 3000 rpm.
We didnt set the dyno on fire but I bet this car lays down a number..
The car is an animal to 6800
This was threw a A4/12-bolt 4.10 and makes 400RWTQ from 3200 to 4800
The car has a dead flat hp curve and its making 350RWHP by 3000 rpm.
We didnt set the dyno on fire but I bet this car lays down a number..
Thread Starter
Launching!
Joined: Jul 2003
Posts: 204
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From: MI
Originally Posted by big dave
I think you should be seeing a bit more power with that combo. That really is a decent sized cam for an lt1. Get those bugs worked out and take 'er to the track.
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TECH Addict
Joined: Jul 2003
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From: Amarillo, Texas
Have you contacted Combination or do you just rant on a forum?
Doesn't seem like those numbers are low...Mustang dyno's are significantly lower. The 9" and 315's will cause the numbers to be lower, too.
FWIW, my full bolt-on LT1 put down 338 rwtq.
Doesn't seem like those numbers are low...Mustang dyno's are significantly lower. The 9" and 315's will cause the numbers to be lower, too.
FWIW, my full bolt-on LT1 put down 338 rwtq.
Thread Starter
Launching!
Joined: Jul 2003
Posts: 204
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From: MI
Originally Posted by ZaneO
Have you contacted Combination or do you just rant on a forum?
11 Second Club
Joined: Jul 2003
Posts: 2,311
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From: loudoun county,va
Originally Posted by ZaneO
Doesn't seem like those numbers are low...Mustang dyno's are significantly lower. The 9" and 315's will cause the numbers to be lower, too.
.
.
exactly.
same car on a dyno jet,
10bolt
3.42 gear
245 tires. 410-420 rwhp
IMHO
