308 heads

[midlifecuda]

I have a set of heads casting number 4448308 which I assume are the "308" heads. Anybody have any input on these heads good or bad as far as performance. I know they are not 202 valves ect. but I have heard that they are a good head...?

 

[Robbie2734]

I have a set I'm using on my build. They are said to flow better then the earlier 360 heads, they usually have a 73cc chamber and can be set up as a quench head. mine came off a 91 truck motor. They are harder to find a good set, look for cracks between the seats.

 

[72bluNblu]

I have a set for my 340 rebuild. They flow about the same in stock form as the older X-heads, but they have a better exhaust port design ( taken from the W2 heads) and lend themselves well to porting.They also have an improved chamber design vs the earlier heads. My set, with a stage 2 port, now flow 264 cfm at .500" lift, a touch better than stock edelbrock heads. Plus they already have hardened seats. They can be opened up to 2.02" intake valves pretty easily as well. They tend to crack, but not as badly as some of the early magnum heads. And of course you'll need to block the smog ports.

73cc's isn't the right chamber size though, typically they're 65-68cc's. Mine checked out at 65cc's. :-D

 

[tom340]

Using the same heads on my 372" SB. 2.02's installed and so far no port work at all. 430HP, 450Tq on a dyno run with only a 650 Thunder series and tiny set of Chevy dyno headers... researching into porting these 308's over the winter downtime, along with installing the tti's when things go back together.

 

[67Baccaruda]

Hi Tom

I have a set also. I wonder myself how well they will perform with the stock 1.88 intakes and some mild porting? If the chambers are 65 cc I wonder what the stock CR of my 89 truck motor was?

 

[tom340]

Hi Tom

I have a set also. I wonder myself how well they will perform with the stock 1.88 intakes and some mild porting? If the chambers are 65 cc I wonder what the stock CR of my 89 truck motor was?

I'm sure somebody will be able to provide some specs for you. I have nothing but my own dyno run (no head flow chart) to reference. I am pretty happy that "both" Mike's referred me to the 308 heads vs. the Edelbrocks $$ at the time of my engine build. My brother Todd sold a '69 Cuda to AdamR about 90 years ago (sic) and that 'Cuda I think had a set of stock 308 swirlports on it.. Mostly a stock 340 engine, ran like a scalded dog.