Is a 235 cc head too big for a street 434 ??

[PTAddict]

Port size can't really be directly compared between 1st gen and LSx motors - port length, port height, valve size, and valve angle differences make the comparison not really useful.

235 CC would generally be considered quite large for a 434 street motor, unless you're going for higher RPM power peak (6500 - 7000). Even then, many engine builders will take the philosophy of using smaller ports. John Lingenfelter used to build 420 CID small blocks with heads in the 190 cc range, shooting for brutal torque and 550 HP or so.

If it was my motor, I'd think about the newest version of AFR 210s or 220s as a starting point. Call Tony Mamo over at AFR and tell him in detail what your goals are - he'll be able to make a recommendation on both heads and cam. I've used 3 sets of AFRs on different builds now, always with excellent results, and AFR's customer service has always been great for me.

[Blown353]

Originally Posted by PTAddict

Port size can't really be directly compared between 1st gen and LSx motors - port length, port height, valve size, and valve angle differences make the comparison not really useful.

235 CC would generally be considered quite large for a 434 street motor, unless you're going for higher RPM power peak (6500 - 7000). Even then, many engine builders will take the philosophy of using smaller ports. John Lingenfelter used to build 420 CID small blocks with heads in the 190 cc range, shooting for brutal torque and 550 HP or so.

If it was my motor, I'd think about the newest version of AFR 210s or 220s as a starting point. Call Tony Mamo over at AFR and tell him in detail what your goals are - he'll be able to make a recommendation on both heads and cam. I've used 3 sets of AFRs on different builds now, always with excellent results, and AFR's customer service has always been great for me.

Exactly what I was getting at only with more words. Heck, for street duty with a reasonable RPM cap in the 6400-6500 range I wouldn't doubt Tony would suggest their new 195 Eliminators, and I bet that 434 would make some mean torque numbers with them.

[70gotboost]

Wouldn't even give a thought to going with anything other than the AFR's!!!

[DB Z28]

I would go with the New 227 AFRS Realy a good head.

[jasonsnova]

not to hijack ur thread but i just ordered a set of afr's new 195's yesterday for my 355, from want ive read they really suppot engines more like a 210cc head with out losing the low end, for your app i would be trying to get a hold of afr's new 210's ....you'll get the hp and some mean torque!!!

[rocketman]

Brodix or AFR's are the best heads period IMO,The only Dart head I use is Big Chiefs on mountian motor stuff,Even the I like Big Duke's better depends on app.

[bluaddict]

I have a 6/71 blown SBC bored .40 over and a 3.85 crank and the heads I have are ported out to the max. I runs like a wild raped ape when I put my foot thru the floor and I believe it still wants to breath more deeply, yea ! I already have Iron eagle 230 with 2.08 and 1.625's and Super Comp Headers 1 7/8 also it ts a tall port Truck motor I was told as I had to have the ports enlarged on my intake to fit ( to short ) along with port matching. I am going to be running a Methenol Injection Intercooler setup soon in my 1978 Z28 Camaro. I also have a Turbo 400 and a set of 3.90 gears as I am in the middle of a teardown on it to add beehive springs, etc. What Do Ya Tink, Claude.

[Stang's Bane]

Originally Posted by PTAddict

Port size can't really be directly compared between 1st gen and LSx motors - port length, port height, valve size, and valve angle differences make the comparison not really useful.

235 CC would generally be considered quite large for a 434 street motor, unless you're going for higher RPM power peak (6500 - 7000). Even then, many engine builders will take the philosophy of using smaller ports. John Lingenfelter used to build 420 CID small blocks with heads in the 190 cc range, shooting for brutal torque and 550 HP or so.

If it was my motor, I'd think about the newest version of AFR 210s or 220s as a starting point. Call Tony Mamo over at AFR and tell him in detail what your goals are - he'll be able to make a recommendation on both heads and cam. I've used 3 sets of AFRs on different builds now, always with excellent results, and AFR's customer service has always been great for me.

I kinda thought that may be the case, that's why I said apples--->oranges.

It is hard to imagine that 2 engines with similiar displacement could be that much different. Oh well, live and learn

[Scotch]

Originally Posted by PTAddict

Port size can't really be directly compared between 1st gen and LSx motors - port length, port height, valve size, and valve angle differences make the comparison not really useful.

235 CC would generally be considered quite large for a 434 street motor, unless you're going for higher RPM power peak (6500 - 7000). Even then, many engine builders will take the philosophy of using smaller ports. John Lingenfelter used to build 420 CID small blocks with heads in the 190 cc range, shooting for brutal torque and 550 HP or so.

If it was my motor, I'd think about the newest version of AFR 210s or 220s as a starting point. Call Tony Mamo over at AFR and tell him in detail what your goals are - he'll be able to make a recommendation on both heads and cam. I've used 3 sets of AFRs on different builds now, always with excellent results, and AFR's customer service has always been great for me.

I was just gonna write the exact same things, start to finish .

Well done. You actually know stuff.

~Scotch~

[Smittys67]

I dont think you can get a head to big for a 434. I have 2 of them with dart 230 ported to the max and there is no hesitaton on the bottom end of them. On the dyno they make 472 ft lbs at 3500 507 at 400 575 at 5000 hp was 635 at 6500. The dyno pulls were not to make peek hp we were messing with lifters and oiling problems.