GM847 + home ported heads dyno results
#1
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Engine had 15,000+ miles on it at time of dyno.
I ported these heads 7 years ago and had no clue what I was doing.
Car is a 93 Camaro with A4, 3600 stall, AS&M headers, Magnaflow exhaust, and 3.42 gears.
The squiggly lines in the graph were coming from the converter not wanting to stay locked up... you could hear it pulsating. The map reading was pretty low(low 90s, I think), so I'm sure either a better CAI(Moroso with possibly dirty filter) or something other than a stock TB would pick up some power. If I had to guess, I'd say an EWP, fix the MAP problem(TB/CAI), and true duals would put this car pretty damn close to 400rwhp... which isn't bad for some junk heads and this cam. 6 speed car would possibly be a tad over 400.
I ported these heads 7 years ago and had no clue what I was doing.
Car is a 93 Camaro with A4, 3600 stall, AS&M headers, Magnaflow exhaust, and 3.42 gears.
The squiggly lines in the graph were coming from the converter not wanting to stay locked up... you could hear it pulsating. The map reading was pretty low(low 90s, I think), so I'm sure either a better CAI(Moroso with possibly dirty filter) or something other than a stock TB would pick up some power. If I had to guess, I'd say an EWP, fix the MAP problem(TB/CAI), and true duals would put this car pretty damn close to 400rwhp... which isn't bad for some junk heads and this cam. 6 speed car would possibly be a tad over 400.
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#8
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6500+
Which I have YET to see on a graph. They claim there's something wrong if they peak that low but they still make more power than other cams. Only down low are they like 10hp lower. And I do mean DOWN LOW, pre 3k which if you are cammed you should pretty much never be in that area in a race. Manuals should launch higher and autos should have higher stalls.
It's just ridiculous how much misinfo is out there. and the people keep recycling other people's quotes instead of showing dyno proof to counter what I keep showing.
Do a search for any thread about that cam. The debates are retarded.
Which I have YET to see on a graph. They claim there's something wrong if they peak that low but they still make more power than other cams. Only down low are they like 10hp lower. And I do mean DOWN LOW, pre 3k which if you are cammed you should pretty much never be in that area in a race. Manuals should launch higher and autos should have higher stalls.
It's just ridiculous how much misinfo is out there. and the people keep recycling other people's quotes instead of showing dyno proof to counter what I keep showing.
Do a search for any thread about that cam. The debates are retarded.
#10
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You should have to apply for a license to post things online, you have no idea how much bad info I've come across, tried, failed, fixed, and facepalmed at the retardation people swear by because they don't know any better.
#13
11 Second Club
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Every car doesn't run at WOT just to go to Wal-Mart. That's why some people choose to run a cam that starts making power a lower rpm...
#15
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6500+
Which I have YET to see on a graph. They claim there's something wrong if they peak that low but they still make more power than other cams. Only down low are they like 10hp lower. And I do mean DOWN LOW, pre 3k which if you are cammed you should pretty much never be in that area in a race. Manuals should launch higher and autos should have higher stalls.
It's just ridiculous how much misinfo is out there. and the people keep recycling other people's quotes instead of showing dyno proof to counter what I keep showing.
Do a search for any thread about that cam. The debates are retarded.
Which I have YET to see on a graph. They claim there's something wrong if they peak that low but they still make more power than other cams. Only down low are they like 10hp lower. And I do mean DOWN LOW, pre 3k which if you are cammed you should pretty much never be in that area in a race. Manuals should launch higher and autos should have higher stalls.
It's just ridiculous how much misinfo is out there. and the people keep recycling other people's quotes instead of showing dyno proof to counter what I keep showing.
Do a search for any thread about that cam. The debates are retarded.
It still stands that the 847 is not the best choice for a street car, unless you do primarily roll racing. He has self ported heads that he admits were done unexperienced which is making it peak early and probably losing a ton of air velocity - the biggest mistake most people make are doing things like opening up the runners and gasket matching the intake ports, when those are not the restrictions in a stock head and that actually hurts your numbers. At 3k he is down an easy 40hp and 50tq from a smaller grind, even on stock heads. You can say what you want about low end not being important, but that is a significant difference.
Without a 4K stall and much bigger gears then the OP has it will not do very well from a dig.
Give it good heads and it will want 6500 peak and to shift at 6700.
Like I said though, as long as you are happy that is all that matters.
#16
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Probably not much less. lol
I'm sure it's making more power down low than a stock cammed car. I think it feels decent down low.
Not sure what roll racing has to do with anything... that's what stalls(A4s) and gearing down(M6s) are for!
I have looked at a bunch of graphs and just ain't seeing what you are talking about. Show me some to save me more trouble.![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
Honestly, my stall and gears seem fine. Hell, 1/4 throttle and it spins my 315s.
I am, thanks!
It still stands that the 847 is not the best choice for a street car, unless you do primarily roll racing.
At 3k he is down an easy 40hp and 50tq from a smaller grind, even on stock heads. You can say what you want about low end not being important, but that is a significant difference.
Without a 4K stall and much bigger gears then the OP has it will not do very well from a dig.
Like I said though, as long as you are happy that is all that matters.
At 3k he is down an easy 40hp and 50tq from a smaller grind, even on stock heads. You can say what you want about low end not being important, but that is a significant difference.
Without a 4K stall and much bigger gears then the OP has it will not do very well from a dig.
Like I said though, as long as you are happy that is all that matters.
I have looked at a bunch of graphs and just ain't seeing what you are talking about. Show me some to save me more trouble.
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
Honestly, my stall and gears seem fine. Hell, 1/4 throttle and it spins my 315s.
I am, thanks!
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
#18
TECH Senior Member
iTrader: (8)
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First of all congrats on the numbers!
That said, I'm just happy my baby cam and stock heads makes the same peak tq you do and more everywhere else in the curve.
Again, I'm not talking crap here just a comparison. I've been looking at a lot of graphs and dont usually see a curve like mine. The only reason I bring it up is because I have several friends 2 in particular have "machine shop ported heads" and one has a cc306, the other a custom cam about the same size as yours and I've spanked them both with my setup. One is a geared M6, one is a stalled auto.
I just think it goes to show what these guys are talking about, all the HP in the world doesnt do you any good 1) if it's in a small rpm window and 2) if you can put it to the ground.
Either of the 2 setups I mentioned would beat me at the track IF they dead hooked, had the gearing, tune and shift points PERFECT.
On the street, I jump them out of the hole because I make 330ft lbs at 2000 RPMS and the tq climbs from there and the car never quits pulling.
Just a comparison, again not taking anything away from your numbers. I just think a small cammed would be a lot closer to you on the track than you think.
Now, get a set of mean ported heads on it (AI 200's come to mind) a little juice to make up for the loss down low and that car will probably RAPE in the 1/4, assuming it hooks good
That said, I'm just happy my baby cam and stock heads makes the same peak tq you do and more everywhere else in the curve.
Again, I'm not talking crap here just a comparison. I've been looking at a lot of graphs and dont usually see a curve like mine. The only reason I bring it up is because I have several friends 2 in particular have "machine shop ported heads" and one has a cc306, the other a custom cam about the same size as yours and I've spanked them both with my setup. One is a geared M6, one is a stalled auto.
I just think it goes to show what these guys are talking about, all the HP in the world doesnt do you any good 1) if it's in a small rpm window and 2) if you can put it to the ground.
Either of the 2 setups I mentioned would beat me at the track IF they dead hooked, had the gearing, tune and shift points PERFECT.
On the street, I jump them out of the hole because I make 330ft lbs at 2000 RPMS and the tq climbs from there and the car never quits pulling.
Just a comparison, again not taking anything away from your numbers. I just think a small cammed would be a lot closer to you on the track than you think.
Now, get a set of mean ported heads on it (AI 200's come to mind) a little juice to make up for the loss down low and that car will probably RAPE in the 1/4, assuming it hooks good
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)