Horsepower estimates?
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Joined: Mar 2009
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From: West Chester, PA
Horsepower estimates? I am installing Absolute Speed 5.3L Stage 2.5 heads, a pretty aggressive grind cam (MS3/MS4 aggressive), 55lb injectors, LS7 lifters, LS2 timing chain, Melling oil pump, Walbro 255 fuel pump and hardened pushrods.
Anyone have any rough estimates on what kind of numbers I will be putting to the ground?
Heads are Comp 977 springs 2.055- 1.575 valves, CNC'ed and hand finished, less than 1k miles on them.
Anyone have any rough estimates on what kind of numbers I will be putting to the ground?
Heads are Comp 977 springs 2.055- 1.575 valves, CNC'ed and hand finished, less than 1k miles on them.
Those injectors are pretty large.
Id guess 430.
Although that depends on auto or manual etc.
We made 420 on a cam only 02 M6 ta. Our custom grind. Could put around a parking lot also. No need to go so aggressive for a number.
Id guess 430.
Although that depends on auto or manual etc.
We made 420 on a cam only 02 M6 ta. Our custom grind. Could put around a parking lot also. No need to go so aggressive for a number.
Thread Starter
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From: West Chester, PA
That is true, after getting the stats back from the machine shop on the springs. Keeping it around .600 lift will probably be best suited, something around the grind of a Futral F14.
Lift doesnt has little to do with how aggressive or "large" a cam is. I like higher lobe lifts but the lobe itself is what is important and the specs together for each combo. It will run alright, but sometimes on ms3/4 cams and 5.3 heads you either have to recess the valves or flycut to fit the cam. Make sure you find that out!
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Brett Foote Thread Starter
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From: West Chester, PA
Change of plans after talking to my guy and getting the specs on my heads back... It is mostly a street, might see track time eventually.
Going with Lunati double springs and a custom grind around .227/.235 and .614/.621(might not go as high) on a 112lsa.
Going with Lunati double springs and a custom grind around .227/.235 and .614/.621(might not go as high) on a 112lsa.
The springs you are getting will more than handle the .600+.
That cam is a moderate cam that will have good midrange to top end with 7° of overlap.
Judging by your bolt-on numbers in your sig I would guess you still have a 3.42 rear that's stock too? You don't want a dog for a street car, and I would always check a set of heads for PTV especially if they were used prior. The whole "it will fit" internet line gets tossed around way too much. I can tell you all day on here that it will work just fine because at the end of the day I am not the one destroying my motor that I just bought a bunch of parts for. Check or have someone check it. Also, check your pushrod length too. Sometimes, not very often, a cam will have a different sized base circle and or the lifter may require something different and you may be better off running a 7.450 or vs. a stock length 7.400. This is just a for instance of course and it could be stock is fine or shorter. Again, the last thing you want is coilbind or PTV issues. Something to think about nonetheless though.
Lol, but to answer your question: It's hard to tell since you may not be sure on the cam you want. It will probably put you over 420rwhp and rwtq will depend on your grind, but I would not expect much over 400 if it even gets that high.
FWIW: I ran (YEARS AGO) a 244/248 .598/.598 115+2 cam on milled stock heads with a mild hand port and pulled 426/391. It was SLOW out of the hole on my stock rear but stupid on the top end.
That cam is a moderate cam that will have good midrange to top end with 7° of overlap.
Judging by your bolt-on numbers in your sig I would guess you still have a 3.42 rear that's stock too? You don't want a dog for a street car, and I would always check a set of heads for PTV especially if they were used prior. The whole "it will fit" internet line gets tossed around way too much. I can tell you all day on here that it will work just fine because at the end of the day I am not the one destroying my motor that I just bought a bunch of parts for. Check or have someone check it. Also, check your pushrod length too. Sometimes, not very often, a cam will have a different sized base circle and or the lifter may require something different and you may be better off running a 7.450 or vs. a stock length 7.400. This is just a for instance of course and it could be stock is fine or shorter. Again, the last thing you want is coilbind or PTV issues. Something to think about nonetheless though.
Lol, but to answer your question: It's hard to tell since you may not be sure on the cam you want. It will probably put you over 420rwhp and rwtq will depend on your grind, but I would not expect much over 400 if it even gets that high.
FWIW: I ran (YEARS AGO) a 244/248 .598/.598 115+2 cam on milled stock heads with a mild hand port and pulled 426/391. It was SLOW out of the hole on my stock rear but stupid on the top end.
OP, I gotta tell you...don't get hung up on the dyno numbers! Case in point: My ride made 420 rwhp n/a. On most other dynos it should be maybe 450-460 rwhp. Now here's the thing....it runs with 500 rwhp cars that weigh the same, have similar gearing, similar drivers, etc...My point is forget whatever number it makes, and go race it against other cars, and take it to the track as well 
My cam only m6 made 427 rwhp ran 10.86 at 126 mph. So I would think 440 rwhp is obtainable. But really who cares. Ppl are more impressed I think with my track times then my dyno numbers lol.
I know I sure am. We are going to coordinate a day to go to the track together and I'm going to let you see what ET you can get with my car.
Thread Starter
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Joined: Mar 2009
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From: West Chester, PA
My bad guys, I forgot to mention that I am doing 4.10's. I am just leaving everything in his hands at this point, stressing me out haha
But I am open to suggestions to throw his way.
But I am open to suggestions to throw his way.
Launching!
Joined: Oct 2012
Posts: 219
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From: near Beech Bend race way
I am installing Absolute Speed 5.3L Stage 2.5 heads, a pretty aggressive grind cam (MS3/MS4 aggressive), 55lb injectors, LS7 lifters, LS2 timing chain, Melling oil pump, Walbro 255 fuel pump and hardened pushrods.
Anyone have any rough estimates on what kind of numbers I will be putting to the ground?
Heads are Comp 977 springs 2.055- 1.575 valves, CNC'ed and hand finished, less than 1k miles on them.
Anyone have any rough estimates on what kind of numbers I will be putting to the ground?
Heads are Comp 977 springs 2.055- 1.575 valves, CNC'ed and hand finished, less than 1k miles on them.