Edelbrock Cam

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Mar 27, 2004 | 07:55 AM

#31

danlee

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From: Delaware

Comp Cams has a conversion kit which contains a 'spider' and the 'dogs' to keep the lifters aligned. This allows you to use 5.0 L roller lifters, which are much cheaper than aftermarket roller lifters. The down side is that it requires some slight machining of the block, which is risky in an assembled engine. Care must be taken to prevent metal filings from getting into the motor.

Mar 29, 2004 | 11:37 PM

#32

Ecuri

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From: Houston/Hope BC

Brent, I don't know who does the math at Holley but it is suspect.
There are several calculators out there, here is one from the enemy camp:
http://www.corvetteactioncenter.com/...ools/carb.html

Mar 30, 2004 | 12:42 AM

#33

BrentKasson

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From: Ottawa, KS

interesting. So the overall consensus is that headers will help out my top end. THat is what I needed to hear. I saw a universal dual exhaust system in my JCWEhitney catalogue. Thank you for the advice. I don't know if I really want to machine the block to accept a hydraulic roller cam, but I do want some more performance, and the hedders sitting in my basement sound like they will help. THank you for your advice. Now, new question, How much more power will a 270H make over that edelbrock cam? I'd like to know if it would be worth the money, featuring I have a new cam. Thank you for the replies. They have been informative.

Mar 30, 2004 | 06:07 AM

#34

CJJTulsa

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"So the overall consensus is that headers will help out my top end."

They should also give a big boost to your low end as well, depending on the tube size. In my experience, smaller tubes seem to improve low-end torque, larger tubes seem to improve the upper end. And I've run Cleveland 4V manifolds, and they didn't even compare to a cheap set of 1 5/8" tube headers.

Mar 30, 2004 | 10:54 AM

#35

Ecuri

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From: Houston/Hope BC

And of course, into 2 1/2 duals, right?. Smear a wad (like a two finger dollup) of plain ol' grease in each tube at installation. This is an econo-coating and will slow rust greatly. I would suggest you have the muffler shop cut the flanges and weld or slip fit the pipes, but that is just me. Tell us how you do passing.

Mar 30, 2004 | 12:46 PM

#36

danlee

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From: Delaware

Edelbrock w/Headers torque = 382@2000 RPM, 403@3500 RPM, HP = 319@5000 RPM
275DEH w/headers torque = 405@2000 RPM, 412@3500 RPM, HP = 324@4500 RPM

270H w/headers T= 429@2000, 426@3500, HP = 318@4500 RPM

Mar 30, 2004 | 02:37 PM

#37

BrentKasson

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From: Ottawa, KS

Yes, 2 1/2" duals. Thank you all for the replies. Hmmm. It looks like that 270H is almost comparable to the 275DEH. Choices, choices. But the numbers on the Edelbrock aren't so bad either. WHat does a 9.5:1 CR do to those numbers, and does it include porting?

Mar 30, 2004 | 03:14 PM

#38

danlee

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From: Delaware

With 9.5:1 CR and headers:
Edelbrock T = 390@2000, 411@3500. HP = 330@4500
275DEH T = 413@2000, 421@3500, HP = 332@4500
270H T = 439@2000, 429@3500, HP = 314@4500

Add ported heads:

Edelbrock T = 386@2000, 416@4000. HP = 356@5000
275DEH T = 409@2000, 427@3500, HP = 356@5000
270H T = 435@2000, 438@3500, HP = 340@4500

Now the longer duration Edelbrock cam is starting to overtake the shorter duration at high RPM, because the motor can breathe better.

Lets try a Crane H278-2:
T= 393@2000, 416@4000, HP = 362@5000 RPM

This cam is similar to the Edelbrock with a little higher lift, but less duration and overlap. This cam wants 10:1 and a stall converter.