Denny McLain

Those of you whom own the competition ported AFR 210’s, (part #1101) can you share with me a little dyno data on how they compare to other heads you have owned?

I’m being pulled a few different directions as one person is saying to buy a set of the competition ported 210’s and let him clean up the the CNC porting. Claims he can pick up 10-15 cfm over the factory work. Another person I know is recommending LT4 heads over the AFR 210’s. Says they will make more power.

The potential kicker is I would have to buy LT4 castings and the AFR’s are quite a bit cheaper to buy factory CNC porting and then have them tweaked. Both people are very knowledgeable and reputable so there may not be any losers in the bunch.

They will be going on a 12 to 1 compression 385ci motor with a GTP 6 cam.

Anybody have actually dyno data to help me out?? Sure would appreciate your thoughts.

Heatmaker

diddo kiddo

Red96Lt1

Don't go LT4 heads. You'll have to buy a new intake if you do. If you're going to spend the money on aftermarket heads, go with the 210's. Obvously I don't have dyno data, JMO.

llafro

From what I understand, you'll have to get a new intake either way (LT4 or AFR heads). Only the smaller AFR heads are LT1. The rest are LT4. In any case, with that big an intake port, even the LT4 intake may not physically seal the whole port (i.e. the top of the intake port could be visible even with the intake on).

mastrdrver

He'll have to buy the LT4 intake anyway bcuz the heads 195 and larger from AFR are made for the LT4 intake.

Denny McLain

The intake is not the issue as I already have a fully ported LT4 intake.

I've had three sets of name brand heads flowed (227 AFR's - LT4's and stage II LT1's) recently and none of them come close to what the vendor says the flow numbers are. I'm currently having Lloyd Elliott rework the Stage II LT1 heads until I can find a head that actually does what everyone says it should do.

I've personally made 450 rwhp and 451 rwt with a SR 236/242 cam and 466 rwhp/425 rwt with a 246/252 SR cam with a set of GTP Stage II LT4's. The LT4's flowed 283/201 @.600.

The vendor of the LT4's I recently tested was talking 302/230 but when flowed, they were 285/201. Not bad..... but basically the same as my old LT4's. The same vendor whom did the 227 AFR’s and stage II LT1’s is a blatant rip-off and the numbers were way off.

I was there actually watching Jordon Musser dyno when he made 471 rwhp with a set of AFR's (don't remember which ones nor do I have flow numbers) on a hot motor so both heads can make pretty good power.

Based upon Jordons numbers, I'm tending to learn towards the AFR's but like everything else, the porters are getting better and better and things do change as I’m sure someone is actually flowing 300 cfm from a set of LT4’s…… but who??

Again..... I'm being told ty two good porters that one prefers the AFR's while the other swears on LT4's. I'm trying to get independent data to see which direction to go. So far I’m obviously leaning towards the AFR’s.

Heatmaker

THought the LT-4's where the better head to go with if you wanted more...power...period...

Why are they so negative all of a sudden...???

Ai

While you can get a GM lt4 casting to peak over 300 @ 28," it isn't exactly easy to do safely & consistently. If you're having to buy a new casting, I'd go with the AFR... Their 210 competition cnc ported castings aren't bad, but could use some touchup work. I actually have a set now I'm going through and don't think an honest 10-15 peak gain is much of a stretch, even working more towards improved midlift #'s .

No dyno data however, sorry Denny .

Denny McLain

That's OK Phil....... I appreciate your experience and wisdom. Thank you very much for your insights.

It's people like you and Lloyd Elliot whom should be appreciated and respected as your not putting out a bunch of inflated flow numbers. People buy heads off of advertised numbers and when the car doesn't make the power they expect, these other shops tell them it's their combo or tune. “Hey, I personally flowed them myself so something isn’t right as we make 450-460 all day long with those heads”…..right!

The "stage II" (you can tell I'm not much into stages) heads done by shop X (tired of bitching about them) were down a good 30-40 cfm flow on the exhaust from the supplied flow sheets.

Nothing in this world can convince me:

a. I’m the only person whom this has happened to.
b. It’s not done on purpose to simply sell more product

Anyway…… looking forward. Still trying to find a reasonable priced head that makes the best power possible. Something short of raised runner heads which need a sheet metal intake.

FASTFATBOY

If you really want a set of heads that flow a no branier 300 CFM at .650 or .700, just get a set of conventional small block heads and have them converted. You can get Pro Topline 235's to flow 330 CFM@.700 with the right porter, mid lift numbers are strong on those heads. They also take conventional valvetrain also a consideration when using some AFR heads. Just have to get them converted to work on a LT1. And most likely will have less in them that a maxed set of 227's, and they will flow more IMO.


David

Denny McLain

The only thing that has me a bit iffy regarding heads converted to reverse flow is I live in Dallas. The summers can be a bit tuff and even with a BCool radiator and HD EP it get's a bit dicy with the air on in traffic.

Do the conversions cool as well?

383Z4ME

Hi Denny,

I feel your pain. I just got my race ready cnc ported 210's ordered just after Thanksgiving last year. They came last Wednesday. I am having them cleaned up and flowed by a local shop. I was too cheap to have them flowed out of the box. If you can wait about two weeks I will give you flow numbers.


Rick

rskrause

Denny: I am sure a good porter could do more with the AFR's, there is simply more meat to work with.

Rich Krause

ledfootz28

ive been researching about heads also and ive came to the conclusion that im going with the 210cc lt4 style afr heads.i havent decided if im going with the race ready or comp ready version.but when i do get the heads im giong to take them to a respected machine shop and see the flow numbers and if they can touch em up a bit to squeeze out every pony.is it worth the 600 bucks from the race ready to comp ready versions?