I wondered if anyone has put a 2.35 valve in a AFR 357 Head and curious about results. I need to replace valves in mine so curious about a bigger intake valve and what effect it would have. Especially MPH. Thanks.

how big is your engine? how big is the valve now?

4.610 x 4.50 --600ci. 2.30 intake 1.88 exhaust looking at new cam but motor went through at 7300 1/8th mile. Only thing I am considering is going to a 2.35 intake on the afr 357s I happy with everything else. Didn't know if anyone had put a 2.35 intake in those heads and what result they had. MPH would be nice but if no change I will stick to a 2.30 valve. I could lay off the honey buns M&M's and Dr. Peppers and pick up some MPH but Them things keep calling my name. Thanks for the reply.

LOL weight is king. I do not have experience with these heads. but from my experience id say you have enough CIs, along with the bore, to get good benefits with a 2.350 valve. As to how much- not sure. What do you currently run? At what weight?
What intake do you run?

2038 weight 4.90's timing 32 to get down some marginal tracks. I had a sv632 intake on it but believe it's to big and made my airflow lazy but that's just me and could be far from the truth. I'm putting my old super Vic back on. Going through motor now so considered changing valve size. Now would be the time. Hope someone chimes in that has done this. I know I could change lots of things to go faster but I bracket race and et doesn't concern me but would like to have some more MPH if this would change anything. Compression is 14-1. It been a good motor so like that I can run the cheaper gas and has lived a long time. Heads havnt been off til now for 10 seasons. Now I have changed bearings springs lifters and timing chain in that time but always leaked good so keep running it. I heard a faint squeal so took it apart and it had cracked a piston from skirt to top so it was a good save or I would be asking about a whole motor.

Just realized you said 357s. Instead of speeding money to put bigger valves in those heads, i would spend it the next step up head(365 TF, 375 profiler, 380 brodix/dart) all of those come with a 2.350 valve. Thatd get you a tenth and a half, maybe more. Then use the sv632 intake you have.

Good catch with the piston being cracked

Yes I thought about the 375x profiler but the 357's still need valves. Plus I really don't know anything other than what I have read about the 375x heads. Thank you for your reply

I RUN THE SAME 357 AFR HEAD,SENT THE HEADS BACK TO AFR FOR PURTING.
ANTHONY MAMMO PORTED THE HEADS AND PUT 2.350 INTAKE VALVES IN,THIS IS A 586 BBC THAT RAN A BEST OF 4.600 @ 149 MPH IN A 1920 UNDERCOVER DRAGSTER.
ANTHONY MAMO WAS THE HEAD DESIGHNER FOR THE 357 HEAD.
THE MORE AIR IN WITH HIGHER VELOSITY THE MORE TORQUE AND HORSE POWER.

You may not be able to put a 2.350 in without shrinking the exhaust, which would require new seats.
Also radial clearance of the intake pocket needs to be checked as well.
A 2.325 would probably work, but you need to mock it up and see what the clearance is at overlap.
And it is not only the larger valve, you need to open the throat a like amount.
I went to 92.5% on a set of Eddie/Musi heads and it liked it.

I would say if you really want to keep the AFR 357 head, call AFR and see what they can tell you.. They should know what can and can't be put into your specific head

NO OTHER CHANGES NEEDED, DONE THAT ALREADY!

VALVE POCKET WILL NEED TO BE OPENED IN PISTON ON INTAKE SIDE

quote:

Originally posted by Bad News:
You may not be able to put a 2.350 in without shrinking the exhaust, which would require new seats.
Also radial clearance of the intake pocket needs to be checked as well.
A 2.325 would probably work, but you need to mock it up and see what the clearance is at overlap.
And it is not only the larger valve, you need to open the throat a like amount.
I went to 92.5% on a set of Eddie/Musi heads and it liked it.

A 2.325 will work! Done it. The larger 2.350 should be checked to ensure at overlap the intake does not hit the exhaust valve. Both should be checked for the piston notch! If you need to cut down the ex valve diameter, it will be minimal and the existing seats will be fine.

Smokinjeff
So the real question here is what are you trying to do? That head is a good head as is! If you had a SV632 intake on the motor and it did not like it then you likely don't have a motor combo needing more air and therefore are unlikely to see much if any performance gains adding a larger valve.

Thanks Guys. I appreciate the replys. Top I agree it's not optimal for Sv632 mainly because of the way I been racing it. I make go down the worst track and then leave it alone for all others. My purpose was thinking I might be able to pickup some MPH with a bigger valve. I went ahead and put a 2.30 back in it for now. Just so I don't run into any issues. I might try some different heads down the road to see what it might do. The combo I had has ran well in past with timing and some rpm in my last car. I have had issues this last year with getting a different dragster which needed lots of stuff changed to make it right. Won 1st race and all seemed well till the trailer caught fire going home. Redone and replaced most Then issue after issue followed. I would go racing and 800 ft change would run same. Change 6 jet sizes and still run same. Sounds great right? HaHa then out of blue slow 2 hundreds or speed up 2 hundreds never new which or when. So did lots of finish line driving. Some I was good but then some I was behind or too much ahead. Frustrating so I thought maybe the sv632 air was lazy by the way I was running it. Sounds like a mess. Pulled motor found cracked piston but sure happened at the end as I heard a faint squeal not a lifter squeal. Also cam pin was broke. And then when I had changed the 4-link and lowered back of car the yoke was bottoming out in rear shorty cover. So I'm putting it back together with old super Vic and will see if I kick ass or on the other end of the ass kicking. I will use the advice given and check things if I do add the 2.35 valve in the future. Thanks All.