How much power from this combo?

[Confortar1]

How much power from: 350, .60 over, 9.7:1 comp., Sportsman II heads, Comp Cams 292h-10, msd Box 6a, and a Carter AFB carb 600 cfm

[jveik]

well, the 350 im building will have similar heads, the comp cams hydraulic Xtreme Energy 268 or 262 (still deliberating that area lol) and 1.6:1 rocker arms, with an edelbrock performer RPM intake and holley 750 double pumper carb... also 1 3/4 inch long tube headers as well and "turbo mufflers" chevy hi-performance magazine built just this exact engine and got 416 horsepower at 5700 rpm and 423 lb/ft of torque at 3700 i believe rpm...

with your cam and heads, the potential high rpm horsepower will probably be over 450 horsepower, but probably less torque especially down low... the reason for your higher hp even with less low and midrange torque is that you would have to use higher rpm's to your advantage lol

p.s. that 600cfm carb might kill your power, i dunno... i would see if a friend had a 750 cfm and put it on there and see if it makes more power... if it doesnt, keep the 600, and if it does, get your own 750 and tune it to your needs

[Confortar1]

thanks for the reply, i am looking into getting new heads and dont know which ones to get, trick flow 23' 195 cc or sportsman II's, any opinions? I'm looking for high rpm power also.

[jveik]

well, the magazine article actually used the trick flow heads 195c.c. and 23 degrees. just like you said above... cant beat the price i guess, although i would make sure to use a dual pattern cam (exhaust is higher lift) because the intake exhaust efficiency is only 73 percent. air flow research makes killer heads i think the intake is 180ishc.c. and they flow with a i/e ratio of 84 percent, so they are good for single pattern cams... the t.f.s. heads made a tiny bit more power up high than the airflow research, but the airflow research gained like 15 lb/ft of torque at some points at lower rpm's...

this is too long and confusing even myself right now, so ill stop babbling on and on... good luck and let us all know what you ended up doing... i have no cash right now cause im 17 and work at mcdonalds still in high school, so if you have good results, i might "steal" your ideas lol... good luck

[jveik]

well, the magazine article actually used the trick flow heads 195c.c. and 23 degrees. just like you said above... cant beat the price i guess, although i would make sure to use a dual pattern cam (exhaust is higher lift) because the intake exhaust efficiency is only 73 percent. air flow research makes killer heads i think the intake is 180ishc.c. and they flow with a i/e ratio of 84 percent, so they are good for single pattern cams... the t.f.s. heads made a tiny bit more power up high than the airflow research, but the airflow research gained like 15 lb/ft of torque at some points at lower rpm's...

this is too long and confusing even myself right now, so ill stop babbling on and on... good luck and let us all know what you ended up doing... i have no cash right now cause im 17 and work at mcdonalds still in high school, so if you have good results, i might "steal" your ideas lol... good luck

[jveik]

sorry bout the double post (crappy computer)

[NOVA71]

I ran this combo on the desktop dyno and guessing that the heads have 2.02/1.60 valves and running large tube headers and high perf mufflers. It made 399hp @ 6000rpm and 390ftlbs @ 4500-5000rpm. Just for the helll of it I switched to AFR190 heads and it spit out 440hp @ 6500 and 408ftlbs @ 5000. Hope this helps. If you want me to run another combo, let me know.

[jveik]

umm... this dyno thing you ran... is that a rating on rear wheel or just crank horsepower?

[NOVA71]

Just at the crank I believe.

Desktop Dyno is a pretty cool program. Has lots of different engines, cams, heads, bore, stroke, compressin ratios, intakes, you name it.

My combo I'm building: 350, bowtie heads 64 cc 2.02/1.60, Dart airgap intake, 9.5 compression ratio, 650 speed demon carb, MSD 6T ignition. Either XE268H (cam i was going to pick) 401hp@6000rpm, 413ftlbs@4500rpm or Magnum270H (cam Comp Cams recommended for me) 385hp@5500rpm, 411ftlbs@4000rpm.

[Confortar1]

I forgot to mention Im runnin a sigle plane intake and 1 5/8 shorty headers, don't know how much it matters but anyways, I would like to find some heads that could put me in the 425-450 range, if i need to change up a few other things as well thats fine also. Any ideas or thoughts is appreciated.

[NOVA71]

Ya, I figured with a cam like that you'd be running a single plane intake. I ran a few other combos just for fun. If you went with a 750 carb the figures would change to 409hp@6000rpm and 404ftlbs@4500rpm. Now with your present combo and 600 carb if you swapped to a Comp Cams XE282HR hydraulic roller cam and roller lifters You be looking at around 460hp@6000rpm and 447ftlbs@5000rpm. Swap to a 750 carb and that would bring 471hp@6000rpm and 454ftlbs@5000rpm. Now for some real fun. If you went with AFR190 heads and the XE282HR cam and roller lifters with the 600 carb you could expect around 510hp@6500rpm and 466ftlbs@5000rpm. That'll fry some tires!!!

Personally I'd put $ into a good set of heads and a good flowing exhaust system. No use having good flowing heads if you can't get rid of the burnt up gases. AFR makes some of the best heads on the market in my opinion. Their small heads usually flow as much as other manufacturers bigger heads. Then if you can afford it I'd get all roller gear. Roller rockers, roller cam and roller lifters. Just remember to keep into consideration the purpose of your build. Are you looking for a race car or a good street car? It's no use going overboard and making a car that's cranking out the HP if it's going to have terrible street manners, if that's where it's going to spend most of it's time. I'd say it sounds like your looking more for a race car anyway with a singleplane intake and a cam like the 292h. Although the xe282hr is more of a street cam and I don't know if it would have the ability to effectively rev to 6500rpm. You may want to go with something like the XR294HR or the Magnum304HR that would operate in a higher rpm range and both would make around 500hp and 450ftlbs of torque. If you want me to run any combos sometime let me know.

Also remember, the more power you make, the more chance something will break.

[Confortar1]

Just to humor myself, what would my combo with a set of vortec heads put down?

[NOVA71]

Vortec heads are nothing to laugh about, even with the smaller 1.94/1.50 valves , they outflow alot of heads out there. With your present combo, just changing to the vortecs showed 384hp@6000rpm and 393ftlbs@4500rpm. Not bad for a cheap set of factory heads.

With 2.02 / 1.60 in the vortecs would change that to 394hp@6000 and 402ftlbs@4500.
Add a 750 cfm carb = 404hp@6000 and 407ftlbs@4500.
Large tube headers & mufflers = 414hp and 410ftlbs.
Large tube headers & no mufflers = 436hp and 422ftlbs.
Put the mufflers back on and add a 100 shot of nitros and you'd have 536hp@6000 and 538ftlbs@4500.

By the way swithing to a roller cam with the vortecs would bump these figures up another 30-40 hp & ftlbs

[Confortar1]

Yeah, I forgot I had a set layin' around with 2.02 valves put in them. Think you could play with some numbers (carb cam ect.) and see what I could put down with these?