CamTom12

iTrader: (1)

How much CFM difference does a radiused inlet make on average over just a bare head?

Say I've got a set of heads that flowed 268 int. and 215 ex. (corrected) at .650 on a 4" bore and 28" of water naked...

How much would you guess they should flow with a radiused inlet?

The guy that flowed them gave me an estimate and it doesn't stack up to where the heads are supposed to be at all...

AlkyInMyBlood

Flowing with out a radiused inlet is just a waste of time and provides no real results. You must have the boundry layer attached to the port wall.

If a guy flowed your heads without a radius you need to find a new cyl head guy, cause he obviously dosent know wtf is goin on.

Sean Collins

You should try to flow the head with the intake bolted on. Provides the most consistent and real world result. You can make most ports flow a ton of air but that behavoir changes with the intake bolted on.

1989GTA

What they said.

Armageddon

iTrader: (41)

I've had some experience with a bench and it seemed, "like the guys above said," much more accurate with the intake on.

CamTom12

iTrader: (1)

Well, the heads are in a box now and have to go on the car tomorrow so there's not much I can do for getting another flowsheet, which is why I thought I'd see what some folks that have used flowbenches had to say about the difference between the two methods

JL ws-6

iTrader: (50)

What you end up getting for heads Cam?

Long time no talk.. what's new? Ya gona be back up this way anytime soon? if so lemme know.. we'll have to get the whole group together again next time you're around

CamTom12

iTrader: (1)

Unfortunately it'll be a while before I end up there again...

I'm heading to TN next as far as duty assignments go, and it's supposed to be a busy time there. I'm definitely down for chillin' with the crew next time I get up there, though!

It's the same set of heads I've had, I was just unhappy with the power I was getting out of them, plus I was having some issues relating to intake valve sealing so I pulled them off and had them cleaned up and a new valve job

JL ws-6

iTrader: (50)

I don't knwo what you picked up... what are they?

Tony Mamo @ AFR

iTrader: (13)

Why would a shop even bother flowing something without an inlet??....

Even clay works pretty well if molded properly (I've seen some "shoddy" clay jobs), but a radiused inlet is always best.

Anyway....I dont know what you were promised but if it was over 300 CFM's you can forget it. My best guess is that your heads will flow more than 10 CFM and less than 20 CFM better with a radiused inlet. Closer to 15 is probably about right....and by the way the disparity will get greater the more the valve is lifted (it may only be 5 CFM at say .200 lift).

Your heads probably flow a peak number in the low/mid 280's but you may want to consider another bench just to verify (with the proper entry and possibly a pipe on the exhaust to simulate a 1.75 header).

Good luck either way...

Tony

CamTom12

iTrader: (1)

Beats me. It was Pilcher's shop so I figured they'd know what they were doing. I haven't a clue...

Yeah, I ended up just slapping them back on the car because I ran out of time to do anything about it. I figure they don't flow for **** which is one of the reasons I made crappy power with the last set-up I had them on.

Oh well. What's some more bad luck after what I've had in this industry? haha

BriancWS6

iTrader: (18)

Sorry your having troubles man. BTW, I got that 400rwtq

JL ws-6

iTrader: (50)

Cam if ya need them.. I still have Brad's old heads.. everyone's playing tire kicker with them.... 850 shipped to your door. Ya probably could get 90% of that for the ones you have now. I wish I knew you were having these issues earlier man.. ya gotta keep in touch more!

Lemme know