Side by side image of 643 vs. 561 castings inside..
Registered User
Joined: Jun 2004
Posts: 398
From: Paragould Ar
Re: Side by side image of 643 vs. 561 castings inside..
I purchased 643 cores from Lloyd to have done. To me it was alot easier than pulling mine off and sending them out. Plus I got to drive my car while I waited. Ill sell my stock heads when they come off to make up the money
Registered User
Joined: Dec 2002
Posts: 1,810
From: Indiana
Re: Side by side image of 643 vs. 561 castings inside..
[QUOTE=SStrokerAce]No they are all 54cc.
The big deal is to make sure you can tell the castings apart so you can get the right set to send to the porters. The internal parts of the port are hard to see the differences unless you have a well trained eye.
Bret[/QUOTE
i can prove otherwise. i had a set of lt1 heads that came right off of my 94 lt1. they flowed 56.6 cc after beeing milled. chambers were'nt touched a bit. so that equals out to be a set of 58cc heads.
back to the topic, can u tell what heads you have with the heads on the car?
The big deal is to make sure you can tell the castings apart so you can get the right set to send to the porters. The internal parts of the port are hard to see the differences unless you have a well trained eye.
Bret[/QUOTE
i can prove otherwise. i had a set of lt1 heads that came right off of my 94 lt1. they flowed 56.6 cc after beeing milled. chambers were'nt touched a bit. so that equals out to be a set of 58cc heads.
back to the topic, can u tell what heads you have with the heads on the car?
Banned
Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
Re: Side by side image of 643 vs. 561 castings inside..
[QUOTE=blackztpi]
The few sets I have CC'd were 53.7/8 to 54.6/7 and that is MORE than one set.
Don't know what the difference is unless it was the plug ya used.If ya don't use the same plug for comparison it don't work.
Only by part number.
Originally Posted by SStrokerAce
No they are all 54cc.
The big deal is to make sure you can tell the castings apart so you can get the right set to send to the porters. The internal parts of the port are hard to see the differences unless you have a well trained eye.
Bret[/QUOTE
i can prove otherwise. i had a set of lt1 heads that came right off of my 94 lt1. they flowed 56.6 cc after beeing milled. chambers were'nt touched a bit. so that equals out to be a set of 58cc heads.
back to the topic, can u tell what heads you have with the heads on the car?
The big deal is to make sure you can tell the castings apart so you can get the right set to send to the porters. The internal parts of the port are hard to see the differences unless you have a well trained eye.
Bret[/QUOTE
i can prove otherwise. i had a set of lt1 heads that came right off of my 94 lt1. they flowed 56.6 cc after beeing milled. chambers were'nt touched a bit. so that equals out to be a set of 58cc heads.
back to the topic, can u tell what heads you have with the heads on the car?
The few sets I have CC'd were 53.7/8 to 54.6/7 and that is MORE than one set.
Don't know what the difference is unless it was the plug ya used.If ya don't use the same plug for comparison it don't work.
Only by part number.
Registered User
Joined: Jan 2006
Posts: 1,127
From: Dallas, TX
I have the 643's ported/polished, so are yall getting them done by LE? How much does he charge? Also are aftermarket heads better or getting them Ported and Polished with like 2.02/1.60 valves? Thanks
Registered User
Joined: Jan 2006
Posts: 1,127
From: Dallas, TX
they already said 643 because you can tell from the picture there is more metal, more room to port and take out of, the walls on the 374's are thinner, bigger isnt always bigger though, you wanna keep the right flow.
