Thread: help with choosing top end combo

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A dual-plane, high-rise intake such as the Edelbrock Performer RPM or Weiand Stealth or Professional Products Typhoon will make more power and torque throughout the range than a single plane or low-rise dual-plane intake.

I like the results on my DynoSim of the Edelbrock 185cc runner aluminum heads on a 355 Chevy. Excellent heads for a reasonable price. Be careful though, I'm talking 185cc runners on the RPM heads, not the 170cc runners on the standard Performer heads. There seems to be a lot of confusion on the parts numbers, so call Edelbrock and tell them exactly what you want. There are also options for combustion chamber size and straight or angle plugs.

Pull your heads and make note of the piston deck height and piston crown configuration so you can figure your static compression ratio with whatever chamber size you will use. You need to know that before choosing a cam.

If you want, I can run DynoSims for you on different combinations. Some people say the software programs are unrealistic, but mine has shown to be within 2% and it's not the definitive number that's important anyway, it's the DIFFERENCE in numbers noted using different combinations of parts. It's the cheap way to find out what works without buying real dyno time and investing in a ton of parts.

Here's a simulation I ran for a fellow on another forum with a 355. His static compression is 10.3:1, which may be a bit high for what you want to do, but it still shows the validity of the Edelbrock 185cc heads....


Lots of cams you could use, but while I was in Edelbrock's site, I picked out the specs on the #7102 and plotted them in my DynoSim software. Looks like it works pretty well with the Edelbrock RPM heads, RPM intake, your 750 carb and 1 5/8" long-tube headers.....

RPM HP TQ
2000 140 367
2500 177 371
3000 228 399
3500 291 437
4000 350 460
4500 407 475
5000 450 473
5500 471 450
6000 478 418
6500 453 366

Use the head gaskets recommended by Edelbrock for these heads and set your squish to 0.035" to 0.045" to run pump gas without detonation.