I told my friend I'd help him get some info, but we can't seem to find exact stats.


What do stock LS-1 heads flow vs. stock LT-1 heads?

intake & exhaust.

 

Lets put it this way... LT1 heads that are ported and polished to mad hell and back flow JUST a teeny tiny bit better than a stock LS1 head.... A friend has his LT1 heads ported and polished to the max, with a 3 angle valve cut in em, with bigger int/exh valves and they only flow a little better than my LS1 heads do (according to the dyno shop guy)...

 

Sounds like someone got a bum port job. LS-1's peak around 230 Intake and LT-1's are low 200's I think stock.

 

The '97-'00 LS1 heads flow right at 240 cfm stock, and the '01-'02 heads have been known to flow up to 260 cfm stock! It's easy to see why the '01 and '02 cars are making some nice power. Just looking for the 241 head casting.

Depending on who ports them, an average stage II LT1 ported head shows around 265 cfm on the intake, and the LT4 head is usually good for another 15-20 cfm. Again, it depends on the head porter. A good stage II LS1 head will flow 295-300 cfm on the intake and 220 cfm on the exhaust, and the stage III heads for added cubic inches will typically flow 315-320 cfm. The stage III 6.0L MTI heads on our '99 Corvette peaked at 321 cfm, and a set of stage III TEA 6.0L heads peaked at 318 cfm. These flow numbers are on a 1020 Super Flow, FYI.

Trevor
Texas Speed & Performance

 

$700 port job got me 271cfm/187cfm @ .550"

 

thanks for the info guys... yeah, my buddy dropped some good $$ on a port job and he swears he didn't pick much power, he's pretty disappointed. LOL