View Full Version : Stock Heads
gUmBaLL68 Sep 19th, 99, 02:40 PM What kind of hp could i get out of a 350 with a mild cam don't know info with 194 or 202 heads ported etc. posi 3.73 gears with a 3000 stall thankx.
holley intake and holley 650fm Double Pump
Don't know much info but all info is helpful
Coach Sep 23rd, 99, 04:44 PM Gumball, you need to supply much more info to get a realistic idea on HP. Like what kind of heads and what is their combustion chamber size (area). Compression ratio plays a part as well as cam design. Headers or exhaust manifolds?
Typical 350's with stock cast iron heads (1.940 intakes and 1.500 exhaust)are around 250 to 300 horse, but you can kick em up to 500+ with the right combination of accessories.
gUmBaLL68 Sep 23rd, 99, 07:21 PM it will probably have 194 open Chamber heads with some port work around the bowl.
11.5:1 domed pistons
310 dur .530 lift comp cam
GM Roller Tip rockers
Street Dominator Intake
Holley 650 cfm Double Pump
3000 stall TH350 with B&M Shift Kit (not sure which kind)
10.5:1 Compression
Thats about all i know thankx
Dave Birdwell Sep 23rd, 99, 07:33 PM Two things come into play here...your cam's powerband is 4000-7500, and stock heads even with some bowl work, will only go to 6500-7000 before they drop off. Some Dart or AFR, or even Edelbrock Victor JR. heads would be a much better choice.
Second, that carb is WAAAAAYYY too small...this engine would need at least a 750 double pumper, if not an 800.
That is not a Mild cam. It is radical. Don't expect to idle below 1200 in gear. You'll need more stall in the converter too. 3500 or 4000 at least.
1 3/4 headers minimum.
With the right parts and heads, this will be about 475-500 horsepower.
gUmBaLL68 Sep 24th, 99, 09:24 AM I thought my cam was very radical but he kept on telling me that it was mild.
Aftermarket heads are out of the question the head work has already been done on the heads.
Not sure about a bigger cfm i have heard that 650 would be just right and any more would be an overkill but i don't know exactly.
Thankx for the hp rating ABOUT http://www.camaros.net/forum/smile.gif
Oh yea this is a daily driver not a race car so i don't want a higher stall i am not sure if the gears will be able to cruise above 3000 as it is
Dave Birdwell Sep 24th, 99, 07:00 PM First of all, with 10.5 Compression, you'll need to run at least 98+ octane. You'll have the timing so retarded to run pump gas it won't make any power, and run hot.
Not to mention the mileage will suck. 3000 stall is not enough with that cam. Believe me. 3000 is barely enough for Camp Cams 292H cam, and that's less cam than yours.
A 650 will work. Won't make any power, but it'll work. A bigger carb makes more power because it is able to distribute the fuel into the air better.
In a nutshell, for a daily driver I would stay below 9.5:1 compression, and around 274-278 duration cam, use your heads and 650 carb, 1 5/8" headers, 2400 stall, and you'd have about 350-375 horsepower. And be able to run premium pump gas, get alot better mileage. Plus your power brakes will work too, if you have them.
Just my opinion, but it's your car, build it how you want it. Let us know what combo you go with and how it works!
Coach Sep 24th, 99, 07:24 PM Gumball, how did you figure your compression ratio at 10.5 to 1?
If you do have that much compression a 650 is going to be too light. 750 would be better.
Thats a good size cam, hope you don't need a lot of vacumn. If you do be ready to install a vacumn booster. 530 lift can cause some problems with valves hitting the heads. Need to check very carefully.
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Lynn Robinson
Pacheco, Ca.
gUmBaLL68 Sep 25th, 99, 04:42 PM Well the guy rambled off 10.5:1 compression he might have said 10:1 but i am pretty sure its 10.5:1 he said i could run pump gas and get through emmisions with about 8-10mpg if i need better gas mileage i will probably goto a Vac Secondary and get a larger cfm probably. The cam i said was the largest he said that would work right with mine that i said he said a few lower but i wanted to see how the biggest cam would work it will probably be a little smaller but not much.
AFter a bit of research it was probably going to be about 300-310 dur with about .517 or .520 (give or take a bit not truely sure engine isn't built).
But he was positive with the compression he said would run fine with 93 octane pump gas. Well thats all i know i will know more on tuesday hope to give more info as the project progesses
Doug Garland Sep 26th, 99, 05:20 AM Built basically the same engine for my friends Impala, :Keith Black pop-ups-10.8:1,Comp Cams 270 duration/470 lift cam, '70 mnodel # 126 large combustion chamber heads,1.94/1.5 S.S. valves, comp cams magnum tip roller rockers,HEI w/hot coil, Z28 oil pump, balanced the assembly and degreed the cam, running a turbo 400 w/ 26-2800 stall and 3.31 gears.It runs fine on 93 octane gas and runs very well, considering it's a VERY BIG car.The actual ststic compression w/ these heads and a thick head gasket is probably close to 10.2:1. I also think that the cam is too big.Just my .02
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gUmBaLL68 Sep 26th, 99, 02:25 PM Doug i am interested to know what the gas mileage was beacause i didn't notice much diff between the 2 except i will not have full rollers but only roller tips and a little larger stall i don't think that the tranny makes to big of a diff.
waiting for the reply gumball
Thankx a lot guys i have learned much from this forum
Doug Garland Sep 26th, 99, 04:50 PM He get @ 11-14 mpg. , that is driven pretty hard, he doesn't cut it any slack. The heads are off it now, it has been built 4 yrs. now and a valve spring broke and dropped a valve.No damage , the valve was off the seat about 1/16 ".The inside of the engine is as clean as it was when we built it.There is minimal carbon build up on the pistons, so it is burning clean.That was what I was afraid of with pop-ups, it not getting a good flame travel around the chambers, and not running good.Both were accomplished with this combination.Plan on a cam change up to a 280 or 292 cam, gear drive and freshen up the bottom end.It should be even stronger.Forgot to tell you, he has a 650 holley and a Torker 2 intake w/ spacer plate on it.I would run a Performer RRM intake , and a good hydraulic cam with @ .500 lift, a little over it is fine.I just don't like a lot of lift in a small block cam.Have had some bad experiences with over .510 lift small block cams.Just my .02 , every person is different.
craggar Sep 29th, 99, 07:49 PM I'm with the majority the cam is to big for the street and the carb is to small.I have a 292 and 10" of vacuum.I also went from a 650 to a 750 vacuum secondaries and noticed the improvement right away.My compression is just over 10:1 and run premium at 38 degrees total timing with no problems.
I would reccomend the 292 cam with 3000 stall(mine is 3000 and works fine around town and good at the track)The heads will work fine with that combo below 6000 rpm.A performer rpm intake would help as well.I am basically describing my combo except I have the performer rpm heads,1.6 roller rockers and 4.11 gears I run low 13's high 12's in a 80 Z28 which is a heavy car.I had camel bump heads last year with 1.94's and 1'50's with no work and ran a best of 13.7 everything else was the same.
Hope this helps give you an idea on what to do.
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