[goatheaven]

Thinking about upgrading to Edelbrock RAM AIR IV Aluminum Heads this winter.

My set up currently is 455 bored .30 over, TRW Forged Pistons, 4X Heads with Comp cam ram air V and Nodular Crankshaft 9799103. With thIs set up at about 375 HP

Who is running 455 with aluminum heads? How much horse power would I be gaining? 20% would be worth it to me. Can I run on pump gas 91 or 93?

Thanks in Advance

[performerrpm]

with 87cc eheads on a 455 u would be at the 10.1 cr. so pumpgas would be fine with this being aluminum heads, with the right cam you could even run the 72s at 11.6 cr but you would need a good cam and 93 octane at the least.


my guess, 87cc heads and headers if u dont have them already. im gonna say 400/425hp range

[TCSGTO]

Check piston to valve clearance with the TRW’s and E-heads. The location of the valve notches on those can cause interference with some cams but it’s not hard to relieve them if need be.

I ran them with a .550” lift solid flat cam and didn’t have an issue but it’s more cam timing than lift that causes issues.

Stock nonported E-heads with that solid cam made just over 500HP on the dyno with 1-3/4” headers, 850 Holley and a RPM intake. There is a lot of room to grow from there.

[ponyakr]

You say you have 4X heads. Do you know what size the combustion chambers are. I ask, because you could have the big chamber heads, which makes your engine low compression. Or, you could have 4X heads that came on a 400 engine, which means you have more CR

You mention Ram Air IV alum heads. Does that mean that you want round port alum heads ?. If not, you can go with D-port alum heads. The D-port E-heads even have exhaust heat riser holes, so that you can use an intake with an exhaust heat crossover & the heads will warm up the intake & carb quicker. This is good for cold weather driving, if that would make a difference.

You posted that the cam you have is a "...Comp cam ram air V...". I assume you mean that you have a CC ram air IV duplicate cam, which is a CC part # 51-116-3 ?

https://www.summitracing.com/parts/cca-51-116-3

Your cam upgrade choice also depends on exactly what kind of driving you'll be doing, how much power you want, and how much you can spend on the upgrades. A hyd roller cam set-up can easily cost $1500 more than a HFT cam set-up, if you buy the high end parts. So, an upgrade to alum heads and a HR roller cam could easily cost $4k -$5k.

https://butlerperformance.com/i-2445...tegory:1287735

https://butlerperformance.com/i-2936...tegory:1272239

If you just want a little more power, you might wanna consider having a complete iron head HFT cam engine built, for just a little more than an alum head HR cam upgrade to your engine. Then, after you install the new engine, you could sell your present engine, That way, you'd have a new engine, with the extra power you want, and it won't cost near as much as just an alum head HR cam upgrade.

http://lenwilliamsautomachine.com/455_Long_Block.html

If you have low CR now, just an iron head upgrade can increase power, keeping your RAIV cam. Iron heads which have smaller chambers than yours, will increase your CR. A little porting, done correctly, will also add a little power. Correctly done 6X heads will increase your power, without changing cams. You can easily spend $2000 & more for ported 6X heads. But, that's cheaper than new alum E-heads.

https://butlerperformance.com/i-2445...tegory:1234782

One option to save a few bucks is to go with the new Speedmaster alum heads.

[ponyakr]

Don't know what kind of tuning was done for your engine to make 375hp. If the ignition timing curve was not optimized, there is some power to be gained by doing that.

Also, don't know if you really want more power above 5000 rpm, or you just want more seat-of-the-pants acceleration. If it's the latter, you might wanna consider a stall converter(if you have auto trans), or a slight rear gear ratio change.

What carb & intake do you have. There may be some possible power gains there.

The idea is that you might wanna consider all the power upgrades you can do, without buying any new high dollar parts. THEN, if you still want more power, you can make some choices.

[77 TRASHCAN]

Originally Posted by TCSGTO

Check piston to valve clearance with the TRW’s and E-heads. The location of the valve notches on those can cause interference with some cams but it’s not hard to relieve them if need be.

I ran them with a .550” lift solid flat cam and didn’t have an issue but it’s more cam timing than lift that causes issues.

Stock nonported E-heads with that solid cam made just over 500HP on the dyno with 1-3/4” headers, 850 Holley and a RPM intake. There is a lot of room to grow from there.

Good info. I have read here that valve placement on E-heads is not the same as factory, and that E heads need to be clearanced for higher than stock rockers.

Kauffman heads have stock valve placement and are clearanced for higher ratio rockers when new.

One of the knocks of the round port E heads is that they were essentially a copy of the RAIV heads.

All info I stated came from here, anybody can dispute any of it, let it out!

[Stripes]

Yes

[64speed]

I built a roller motor and I got my heads and rotating assembly from Butler. I had them do the porting to 315 cfm option and although I haven’t been able to drive the car it sounds sick on the engine stand

[ponyakr]

" I built a roller motor and...it sounds sick on the engine stand "


Ya'll younger guys will just have to excuse me. But, if I said my motor sounds sick on the engine stand, I'd mean that it sounded really bad, as in NOT good at all, ruff, about to die, lock up, or blow up maybe.

I'm not around young folks very much at all. But, just from the way that post was formed, I have to assume that his definition of the word "sick' is NOT the same as MY definition of the word sick. Am I correct ?

Assuming that maybe his use of that word is sorta like saying a fast car is "bad".

If I'm off here, some of you young bucks fill me in on the current street definition of the word "sick", as it was used here.

That's all for me. Nite all.

[64speed]

Yes I meant it in the context of awesome

[TheGrudge]

Funny - “sick” was to the 90’s what “rad” was to the 80’s. Both have made a comeback.

[pastry_chef]

Originally Posted by TheGrudge

Funny - “sick” was to the 90’s what “rad” was to the 80’s. Both have made a comeback.

https://www.youtube.com/watch?v=Urg-EqR-pHc

[TheGrudge]

Originally Posted by pastry_chef

https://www.youtube.com/watch?v=Urg-EqR-pHc

🤣 That series hasn’t aged!

[KEN CROCIE]

77-- Copies of the RA4 head? What's wrong with that? What exactly are the "knocks"? No dig, just never heard anything bad about a RA4. FYI, back in 89 or 90 I loaned Edelbrock my ported and Extrude Honed 455 HO heads for it's Pontiac alum. head project. The production heads flow almost exactly the same as my 197s. Coincidence? They were originally going to offer them at only 72 cc, but I consulted with them on the merits of offering an 87 cc version .

[PunchT37]

Originally Posted by KEN CROCIE

77-- Copies of the RA4 head? What's wrong with that? What exactly are the "knocks"? No dig, just never heard anything bad about a RA4. FYI, back in 89 or 90 I loaned Edelbrock my ported and Extrude Honed 455 HO heads for it's Pontiac alum. head project. The production heads flow almost exactly the same as my 197s. Coincidence? They were originally going to offer them at only 72 cc, but I consulted with them on the merits of offering an 87 cc version .

And thanks for your contributions.

[Steve C.]

"Edelbrock Corporation in Torrance, California, has been producing high-performance intake manifolds for Pontiac V-8s since the 1950s. It had been producing aftermarket cast-aluminum cylinder heads for several years, too, but not where Pontiacs were concerned. “During the mid-1990s, we recognized a large demand for a high-flow Pontiac cylinder head,” ,” says Smitty Smith, Edelbrock’s technical sales coordinator. “We teamed with Ken Crocie of H-O Racing to develop a cylinder head patterned after Pontiac’s desirable R/A-IV casting and introduced our Performer RPM in 1995.”

Source:

An Exclusive Look At Edelbrock’s New Performer RPM CNC for Pontiac V-8
Written by Rocky Rotella on October 15, 2014

( Updating the head to a modern heart-shaped combustion chamber )

https://www.hotrod.com/articles/an-e...r-pontiac-v-8/


.

[bulletpruf]

I'm interested as well; thinking about replacing the nicely ported 5C's on my 461 for a pair of aluminum heads.

Curious if anyone has flow numbers on stock Edelbrocks - round port and d port - in the different configurations. Would also be nice to see how the Speedmaster heads stack up, as they are significantly less expensive.

[Steve C.]

Flow numbers on page 118

https://edelbrock-files-v1.s3.amazon...ck-Catalog.pdf


.

[Sirrotica]

PONTIAC

LIFT_______.100_____.200_____.300_____.400____.500 _____.600

#60579 72 / 56 138 / 106 198 / 141 239 / 163 264 / 175 275 / 185 – – –

#60599 71 / 69 143 / 120 208 / 151 253 / 173 272 / 191 286 / 199 – – –

#61569 65 / 52 140 / 105 201 / 131 236 / 145 250 / 151 257 / 156 258 / 157

#61599 65 / 52 136 / 103 199 / 130 237 / 146 256 / 151 263 / 157 263 /