Thoughts on my cam and intake choice? Okay, my converter, too!

[nikwho]

Hello all,
I grenaded my 383 and have a +0.040" over 350 that I am building for my '59. It's a weekend cruiser/hot rod. Has Camaro subframe, QA1 tubular control arms, 4 wheel disc brakes, Helwig fat sway bar, Hotchkiss dual rate coils, Bilstein shocks up front, Viking coilovers in the rear. Has a built Currie 9", 4.10 R&P, built TH350, 2,800 stall converter.

4 bolt block, forged pistons, 357 cubic inches. +5cc relief pistons, 0.010" deck, 0.039" compressed head gasket with 4.060" bore. IIRC, this put me at around 10.6:1 compression with my 64cc chamber Dart Pro 1 heads. 200cc intake runners. I live at 6,800' ASL, but venture to lower elevations periodically. 650 cfm Quick Fuel w/ mechanical secondaries. I have an MSD HEI, Accel shorty header plugs, 4 heat range. I have 1.5:1 and 1.6:1 full roller rockers, so can run either, or play with mixed sets. Truck has 1 5/8" mid length Heddman headers, 3" mandrel bent exhaust, with dual 3" Flowmasters and 3" crossover "H" pipe, and electric cutouts right after the headers.

Camshaft: HFT, 234° (i)/244° (e) advertised, @ 0.50".
Advertised Duration:
303 int./313 exh.

Valve Lift with Factory Rocker Arm Ratio:
0.487 int./0.508 exh.

LSA is 114°. I chose this, because I run power brakes, and want to pull enough vacuum to operate them. I have a vacuum reservoir, if needed.

Cam specs say 3,000-6,500 RPM. I figure with my 2,800 stall converter and 4.11 gears, I should be in pretty good shape there.

Regarding intake manifolds, I have a Weiand "X-Cellerator" single plane intake AND an Edlebrock Performer RPM, along with 1"-3" spacers to play with.

I was planning on 36°-38° of total timing. I run 91 octane ethanol free fuel.

Thoughts? Obviously I'll give up a little on the bottom running the single plane, AND the 114° Lobe Separation Angle, but will turn some RPM with the 4.11 gears. I have the Performer RPM, but think that this might be a combo that would like the single plane?

I added the pictures for interest. Last picture shows the aforementioned Weiand single plane intake. It's mounted and ready to fire to break this combo in. Rotating assembly has 800 miles on build. Cam has no miles. I haven't fired yet, as I haven't confirmed the springs pressures that are in the Dart Pro-1 heads. If I am not mistaken, they're these heads came with springs for a mechanical/solid flat tappet cam.

I will likely swap to a roller cam before too long. Just had everything to pit this together, so here's what I got.

[Rickysnickers]

Since your engine appears to be somewhat built, why not wait until you have the money to upgrade to the roller cam, before putting it all back together? Also, and I'm only asking, but isn't a 650 cfm carb a little small for that engine?

[geezer#99]

I built a similar 350 for my 56 210 except I used twisted wedge heads and had slightly less compression of 9.9 to 1. Same cam specs. Had vac readings near 15hg. Idled choppy at 700 rpm. I used a performer rpm and the old standby Holley 3310 750 vs. Ran a ton of initial. Motor liked 22 initial. Limited the hei to 12 mechanical and an extra 10 from the vac pot.
Instant 6 grand in 1st and 2nd. Ran a sag 4 speed with the 3.11 first gear and a stock 3.7 no-posi rear gear.
Looked into a single plane but decided that I normally wouldn’t be cranking it to 6 grand much and just normally cruised at 3000 rpm.
Likely not much difference hp wise between the two intakes.

[nikwho]

Originally Posted by Rickysnickers

Since your engine appears to be somewhat built, why not wait until you have the money to upgrade to the roller cam, before putting it all back together? Also, and I'm only asking, but isn't a 650 cfm carb a little small for that engine?

Engine is buttoned up, with the cam already. Lash set, oil pump primed, filled with coolant. It will be ready to fire once I hook up the exhaust to the headers. I didn't want to rush picking out a roller cam. I've had this and other engines in and out of this truck so much, that it doesn't even bother me anymore.

And, regarding the carb size, I don't think so. This engine has never revved about 6,300. May be different with this camshaft, though. But, 6,300 (RPM) X 357 (cubic inches) ÷ 3,456 = 650.78. So, a 650 is ideal for this engine up to 6,300 RPM. In addition, I live at 6,800' ASL. So our air is a bit thinner anyway. I think that the carb is ideal for the engine.

[nikwho]

Originally Posted by geezer#99

I built a similar 350 for my 56 210 except I used twisted wedge heads and had slightly less compression of 9.9 to 1. Same cam specs. Had vac readings near 15hg. Idled choppy at 700 rpm. I used a performer rpm and the old standby Holley 3310 750 vs. Ran a ton of initial. Motor liked 22 initial. Limited the hei to 12 mechanical and an extra 10 from the vac pot.
Instant 6 grand in 1st and 2nd. Ran a sag 4 speed with the 3.11 first gear and a stock 3.7 no-posi rear gear.
Looked into a single plane but decided that I normally wouldn’t be cranking it to 6 grand much and just normally cruised at 3000 rpm.
Likely not much difference hp wise between the two intakes.

I have been thinking about it, and think that the Edlebrock Performer RPM is the obvious choice. But, I do think that I'll run it first with the single plane, just for giggles.

[nikwho]

Originally Posted by Rickysnickers

Since your engine appears to be somewhat built, why not wait until you have the money to upgrade to the roller cam, before putting it all back together? Also, and I'm only asking, but isn't a 650 cfm carb a little small for that engine?

Perhaps a more honest answer to your question is that if I'm going to spend over a grand for a camshaft, I think that I'll probably just build myself an LS engine! I've steered clear of them all this time. Picking up a 6.0 today. I don't know what it will go in, but I am getting closer to crossing over to the dark side.

[blazer2007]

here is a interesting video I came across you might like on cam and other things that work. https://www.youtube.com/watch?v=v6rmbFZawgk

[Rickysnickers]

Originally Posted by nikwho

Perhaps a more honest answer to your question is that if I'm going to spend over a grand for a camshaft, I think that I'll probably just build myself an LS engine! I've steered clear of them all this time. Picking up a 6.0 today. I don't know what it will go in, but I am getting closer to crossing over to the dark side.

HAHAHAHAHAHA!!! I was asking based on the picture of the engine being partially assembled, no nit picking from me!! If you go with the LS, post plenty of pictures

[Tom]

Originally Posted by nikwho

But, 6,300 (RPM) X 357 (cubic inches) ÷ 3,456 = 650.78. So, a 650 is ideal for this engine up to 6,300 RPM. In addition, I live at 6,800' ASL. So our air is a bit thinner anyway. I think that the carb is ideal for the engine.

Thats assuming no intake restriction, which is impossible and why larger cfm then what should be required always make a bit more HP on the dyno [to a point obviously] That being said, I don't see the carb as a problem.

Run the single plane. The RPM intake would be like trying to band aid the power band, but with a 2800rpm convertor why would you need more torque where the convertor just flashes right past?