133.5 Cam # & Edelbrock’s Supposedly Lame BBC ‘E’ Heads

[David Vizard]

Gary,
You asked:-
How about a Power Adder Cam thread?
Differences in Blower, Turbo, Nitrous

Yes I can do something there but I need to hold off on it for a while. This thread has become all about the 133.5 # and no one has commented on the Edelbrock heads.
I have a set of the rolled E-Street heads here (22 degrees) that I am going to port. My late and sorely missed friend Roger Dr. Air Helgesen ported a set of these for an ST poster and I would like, if possible, whoever that may have been to let me know how they went. The set that I am doing is the next stage on from those. Much the same everywhere except from a 1/2 inch before the valve seat to about 3/4 into the chamber. Roger and I worked on this but he passed before we could start a real working set of heads.

DV

[David Vizard]

Gary,
You asked:-
How about a Power Adder Cam thread?
Differences in Blower, Turbo, Nitrous

Just as a starter here doing a positive displacement cam is a straightforward deal as is a nitrous cam.
All you need to know here is the amount of extra oxygen being digested by the engine.
The real difficult one is a cam for a turbo motor.
If you see a catalog cam that says it's a good choice for a turbo motor they are probably as much in the dark as to what is needed as a typical cam buying customer.

Without having any idea of the pressure ratio's intake/exhaust across the engine at WOT a cam cannot be speced out.

I will go into details on this for my next post - bit short of time at the moment.
DV

[sjre]

David you commented on the edelbrock heads without porting and made 600= hp with a hyd 268 ft cam.I recently did a 496 with brodix 294 heads,286-296 258-266 @ .050 110 in at 104 703 lift roller ,10.5 -1 comp. low tens. rings 1050 dominator 454o int and made 650hp-630 tq.at 6300. Am i crazy because your hp with ede heads/hyd cam makes this 496 look like crap,or are these ede heads far better than everyone thinks??You say your formula will produce 60+ hp 60+torque but on a bbc we were trying to raise peak hp from 6300 to 6500 plus but wherever we put the cam 63-64 was the max.These heads are less cc than the edys but i believe the brodix flow better. Any comments??

[David Vizard]

David you commented on the edelbrock heads without porting and made 600= hp with a hyd 268 ft cam.I recently did a 496 with brodix 294 heads,286-296 258-266 @ .050 110 in at 104 703 lift roller ,10.5 -1 comp. low tens. rings 1050 dominator 454o int and made 650hp-630 tq.at 6300. Am i crazy because your hp with ede heads/hyd cam makes this 496 look like crap,or are these ede heads far better than everyone thinks??You say your formula will produce 60+ hp 60+torque but on a bbc we were trying to raise peak hp from 6300 to 6500 plus but wherever we put the cam 63-64 was the max.These heads are less cc than the edys but i believe the brodix flow better. Any comments??

Your results look a little on the shy side here. Our typical 496's for say street strip use typically top the 750 HP mark and make close to 700 lbs-ft. In this range we use a 320 cc port volume head spec with 2.3 inch valves. This is with a 10.5/1 CR so it runs pump gas. The cams for these builds are typically about 248-252 at 0.050 and lift the valves about 0.770 -0.790. Most important is that for the combo we use the cam LCA is 106-107. Could be my BB Chevy books would be of assistance here. Try amazon.com for such. From 511's we have seen better than 715 lbs-ft and from 525's about 740 lbs-ft.
DV

[sjre]

David you said 2.3 valves ,these have 2.25 . the cam you typically use is 248-252 this is larger but not 106-107 . Where do these typically make peak hp ? Also how much do you figure you lose with a 20cc less cyl head.Also these brodix have a poor i/e ratio how do you correct for that?

Thanks for your input.

[David Vizard]

David you said 2.3 valves ,these have 2.25 . the cam you typically use is 248-252 this is larger but not 106-107 . Where do these typically make peak hp ? Also how much do you figure you lose with a 20cc less cyl head.Also these brodix have a poor i/e ratio how do you correct for that?

Thanks for your input.

Because they are making a lot of torque the builds I am doing make peak power at relatively low rpm though they can be usefully turned past 7000.

It's not so much the port cc here as being a little too small does not hurt the results as being a little too big. At the end of the day it's all about airflow.
Is it the exhaust flow that's down in relation to the intake? if so add exhaust duration. there will b e a loss of torque at rpm less than about 4500.
DV

[HDBD]

David
Sorry to head about Roger. Great guy. He helped me with some reversion issues I had with Harley stuff.

[David Vizard]

David
Sorry to head about Roger. Great guy. He helped me with some reversion issues I had with Harley stuff.

Yes Roger was a highly respected and liked guy. You are just one of many hundreds he shared with.

Although the subject got diverted some I just want to make it clear that those E-street BB chevy heads are a great entry level deal and will really produce when used correctly.

With that said I think I am done on this thread but I will start one, as requested, on cams for power adders so look out for that

DV

[mdabbott2009]

David I sent you a pm