Performer RPM Magnum heads?

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glockr

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How well do they perform? I'm having a hard time finding LA blocks so it looks like I'm going with a Magnum block if I want to build a 360. Only other 2 choices seem to be the stock heads (crack prone) or the new cast-in-China EQ heads (poor flow compared to the original Australian EQ heads). I'd like to end up with an engine that can run mid to low 11's in a 3000 lb car with good suspension and torque converter. How much work would the Eddy's take to support that? Also, can anyone recommend a good head porter that doesn't have a year lead time?
 
How well do they perform? I'm having a hard time finding LA blocks so it looks like I'm going with a Magnum block if I want to build a 360. Only other 2 choices seem to be the stock heads (crack prone) or the new cast-in-China EQ heads (poor flow compared to the original Australian EQ heads). I'd like to end up with an engine that can run mid to low 11's in a 3000 lb car with good suspension and torque converter. How much work would the Eddy's take to support that? Also, can anyone recommend a good head porter that doesn't have a year lead time?
if you buy EQ heads, you will get the choice of intake bolt pattern - magnum or LA, which is nice. BUT - HEED MY WARNING: inspect the heads by disassembly. IF you want proof, watch my video !!
 
If you can find a pre magnum roller LA motor(89-93 I believe)that would be great. They used the LA 308 heads and some came with the roller cam in them. I have 2 of them and 1 came with the roller and 1 did not. You can run the magnum or LA type heads on them.
Everybody keeps repeating about how crack prone the Magnum stock head is.
So far I have never had a cracked Magnum head.(8 sets so far) Now from what I have heard the crack in the Magnum head is a dry crack and can be removed by simply, although not necessarily cheaply, having valve seats put in.
@MOPAROFFICIAL is who did my LA heads for my roller motor. He did a mild not wild(260 @ .500) porting job for me but he went way beyond the normal helping me with my heads. He is located around San Diego CA.

 
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Go the Magnum route and use trick flow heads and the Harland sharp rockers. TTI 1-3/4-1-7/8 headers. Set your pistons up for a pump gas ratio as the TF heads have a small chamber and a zero deck height could be hard to on feed pump gas. I got away with it (zero deck height slugs and TF heads) with 93 octane. Small hyd roller cam @ 224@050.

Your cam selection should start with at least another 30*’s @050.
I’d be looking at a solid cam for a LA and a solid roller for the Magnum mill.
 
Go the Magnum route and use trick flow heads and the Harland sharp rockers. TTI 1-3/4-1-7/8 headers. Set your pistons up for a pump gas ratio as the TF heads have a small chamber and a zero deck height could be hard to on feed pump gas. I got away with it (zero deck height slugs and TF heads) with 93 octane. Small hyd roller cam @ 224@050.

Your cam selection should start with at least another 30*’s @050.
I’d be looking at a solid cam for a LA and a solid roller for the Magnum mill.
I thought about that, but I can't wrap my brain around the idea of shaft mounted rocker arms with no oil being fed through the rocker shaft. How does Trick Flow handle oiling to the rockers?
 
How well do they perform? I'm having a hard time finding LA blocks so it looks like I'm going with a Magnum block if I want to build a 360. Only other 2 choices seem to be the stock heads (crack prone) or the new cast-in-China EQ heads (poor flow compared to the original Australian EQ heads). I'd like to end up with an engine that can run mid to low 11's in a 3000 lb car with good suspension and torque converter. How much work would the Eddy's take to support that? Also, can anyone recommend a good head porter that doesn't have a year lead time?
The Magnum and LA versions of the Edelbrock RPM heads have similar ports, so power potential should be considered about equal in stock, out of the box configuration. However, the Magnum version has a smaller, modern style chamber. I often wonder why Edelbrock does not offer an LA version with the Magnum chamber. Also the Magnum version comes with 3/8” studs for use with Chevy small block roller rocker arms, so tons of rockers are available in all price categories.

Running a Magnum block does not mean you must run Magnum heads. You can run LA heads. If the Magnum is an early block and has LA oiling drilled, just install LA cam bearings and LA based camshaft to oil through the heads and rocker shaft. If the Magnum block is not drilled for LA oiling, you can still use LA heads with a rocker arm that allows pushrod oiling, like Comp Cams Ultra Pro Magnum and clones. This is how the Trick Flow 190 head works on the Magnum block with the correct Harland Sharp rocker srms.
 
I put a set on my magnum 408 stroker. The reason I went this route was because I could use SBC roller rocker arms that were way less expensive than using the trick flow heads with the harland sharp rocker arm setup. I’m extremely happy with he outcome.
 
@MOPAROFFICIAL has done some research work with the new iron magnum speed master heads. IIRC, they’re a decently heavy iron casting but would eat up some time getting the full potential from them. Bare speed master aluminum heads are still available, too.
 
I thought about that, but I can't wrap my brain around the idea of shaft mounted rocker arms with no oil being fed through the rocker shaft. How does Trick Flow handle oiling to the rockers?

Pushrod oiling. Works fine.
 
I have a set on my Magnum 408. Mild cam, pump gas, 3350 pound Dart, 3.55 gears and it runs 11.55 @114. No porting or anything fancy, it's a garage built street car. No Dyno sheets or anything unfortunately.

I had EQ heads on a 360 Magnum in the same car. It ran 12.60s. Same cam, similar compression, same trans/gear/tire, etc.
 
What are you doing/did for a cam?

I have a set on my Magnum 408. Mild cam, pump gas, 3350 pound Dart, 3.55 gears and it runs 11.55 @114. No porting or anything fancy, it's a garage built street car. No Dyno sheets or anything unfortunately.

I had EQ heads on a 360 Magnum in the same car. It ran 12.60s. Same cam, similar compression, same trans/gear/tire, etc.
 
I have a set on my Magnum 408. Mild cam, pump gas, 3350 pound Dart, 3.55 gears and it runs 11.55 @114. No porting or anything fancy, it's a garage built street car. No Dyno sheets or anything unfortunately.

I had EQ heads on a 360 Magnum in the same car. It ran 12.60s. Same cam, similar compression, same trans/gear/tire, etc.
Thanks. I like time slip results better than dyno sheets.
 
What are you doing/did for a cam?
It's a Hughes hydraulic roller cam. I'll have to find the cam card, it's been awhile. But it's something like [email protected] and .570 lift.

I had a smaller hughes cam with the 360/EQ heads at first, I think it was a [email protected] and .540 lift. It went 12.90s. The car was a little lighter then with some of the interior missing.
 
Running a Magnum block does not mean you must run Magnum heads. You can run LA heads. If the Magnum is an early block and has LA oiling drilled, just install LA cam bearings and LA based camshaft to oil through the heads and rocker shaft. If the Magnum block is not drilled for LA oiling, you can still use LA heads with a rocker arm that allows pushrod oiling, like Comp Cams Ultra Pro Magnum and clones. This is how the Trick Flow 190 head works on the Magnum block with the correct Harland Sharp rocker srms.
Besides the Ultra Pro Magnum rockers, what clones can also do pushrod oiling to the shaft? Looked at Speedmaster but they just say they oil to the pushrod cup, nothing about routing any of that oil to the rocker shaft. Can't find anyone with the Ultra Pro's in stock.
 
PRW rockers allow pushrod oiling. The speedmaster rockers look to be a copy of the PRWs (or more likely made in the same factory as a more budget friendly line)
 
It's a Hughes hydraulic roller cam. I'll have to find the cam card, it's been awhile. But it's something like [email protected] and .570 lift.
Wow! Maximization of that cam and combo there to be in the 11’s. Woooooo
I had a smaller hughes cam with the 360/EQ heads at first, I think it was a [email protected] and .540 lift. It went 12.90s. The car was a little lighter then with some of the interior missing.
An old member here that used to live close to me ran in the 12’s as well in his Duster with a Crane hyd @ 218@050. More of a race car than a street car, though plated with lights and such….
It was a well done up car and combo considering such a small cam running into the 12’s.
 
Besides the Ultra Pro Magnum rockers, what clones can also do pushrod oiling to the shaft? Looked at Speedmaster but they just say they oil to the pushrod cup, nothing about routing any of that oil to the rocker shaft. Can't find anyone with the Ultra Pro's in stock.

Mancini Racing sells pushrod oiling rockers
 
PRW rockers allow pushrod oiling. The speedmaster rockers look to be a copy of the PRWs (or more likely made in the same factory as a more budget friendly line)
The PRW is a copy of the Comp Ultra Pro Magnum rockers. Same with Speedmaster, Mancini, and anyone else selling that same style stainless body with roller tip. I have a set of Comp and a set of Speedmaster, both in 1.5 ratio, and everything I can measure is exactly the same. I never had the PRW stuff yet.

Editing to add;
I measured the Comp and the Speedmaster to see what each one would take from B3 Racing for a correction kit on Edelbrock LA heads and found all of those measurements were the same, within one or two thousandths.

Anyone that says Speedmaster or PRW, or whomever needs correction to clear the spring and retainer should know the Comp version needs the correction as well.
 
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How well do they perform? I'm having a hard time finding LA blocks so it looks like I'm going with a Magnum block if I want to build a 360. Only other 2 choices seem to be the stock heads (crack prone) or the new cast-in-China EQ heads (poor flow compared to the original Australian EQ heads). I'd like to end up with an engine that can run mid to low 11's in a 3000 lb car with good suspension and torque converter. How much work would the Eddy's take to support that? Also, can anyone recommend a good head porter that doesn't have a year lead time?
fully ported they will support well over 500HP which you'll need to get low 11's. I did a 422 sb a few years ago using the Eddy mag heads, our cam, Indy intake, 950 carb and 10.5:1 and made 565HP with it. It also made 550's TQ.
 
fully ported they will support well over 500HP which you'll need to get low 11's. I did a 422 sb a few years ago using the Eddy mag heads, our cam, Indy intake, 950 carb and 10.5:1 and made 565HP with it. It also made 550's TQ.
1.3 lbs-ft per cid solid build
 
fully ported they will support well over 500HP which you'll need to get low 11's. I did a 422 sb a few years ago using the Eddy mag heads, our cam, Indy intake, 950 carb and 10.5:1 and made 565HP with it. It also made 550's TQ.

you won’t need over 500 horse to run low 11’s with a 3000 pound car.
I went 11.26 with a 3350 pound car and wasn’t remotely close to 500 horse. More like maybe 450, maybe.
At 3000 pounds I would have dipped into the 10’s rather easily.
 
you won’t need over 500 horse to run low 11’s with a 3000 pound car.
I went 11.26 with a 3350 pound car and wasn’t remotely close to 500 horse. More like maybe 450, maybe.
At 3000 pounds I would have dipped into the 10’s rather easily.


I was kinda surprised by that comment too. My sons stock crank Edelbrock headed 360 ran 6.54 at 3200 pounds which if you convert over is a 10.35 or quicker.
 
fully ported they will support well over 500HP which you'll need to get low 11's. I did a 422 sb a few years ago using the Eddy mag heads, our cam, Indy intake, 950 carb and 10.5:1 and made 565HP with it. It also made 550's TQ.
What cam?
 
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