[prostcelica]

Hey Guys. The original plan was to get a set of AFR 180's and run a flat tappet cam. After some good info from you guys I changed the plan to going with a Patriot freedom series 185, port and polish and put a hydraulic roller. I went to buy the Patriot heads yesterday from one of ther distributors. They spoke to patriot and patriot said they dont have the cores to make the heads and wont probably wont THIS YEAR!! as they are having finacial issues.

My question is what do you guys think about keeping the same plan but subing the Patriots for the Dart SHP180's?? THe out of the box flow doesnt look great but I know flow doesnt tell the whole storey.

355 SBC 10.3:1 Stock internals
RPM Air gap
Comp XER294
crower rolller rockers 1.6 int - 1.5 exh. (got a deal on them)
Holley 670 street avenger

[ap72]

They're iron heads, and heavy castings but nothing great without a lot of porting.

I really don't see any appeal for them unless you're required to use them by racing rules.

Since you were looking at patriot I assume you want aluminum offshore heads- there are plenty of options available for that. Also with that cam id get a 195-210cc port not a tiny 180cc port.

[2wld4u]

check out the 195cc trick flow heads Fast as cast, they are as cast off of cnc ported versions..




Trick Flow® Super 23® 195 Cylinder Heads for Small Block Chevrolet - trickflow.com

here is the flow sheet as well..

http://static.trickflow.com/global/i...195%2064cc.pdf

and here is my choice for your build the 215 cc

http://www.trickflow.com/partdetail....6&autoview=sku

and flow sheet..

http://static.trickflow.com/global/i...215%2067cc.pdf

and dyno example

http://static.trickflow.com/global/i...up23%20215.pdf

[prostcelica]

The Dart SHP heads I was looking at are aluminum. They have a dual valve sping for use with hydraulic roller cam. I'd post the link on the heads but I'm writing this on my phone. Ill attach the link later when I'm on my computer.

[dave350v8]

I bought some skip white procomp 210cc for mine! Look really good! I will get shot for this now.........

[CNC BLOCKS NE]

Originally Posted by ap72

They're iron heads, and heavy castings but nothing great without a lot of porting.

I really don't see any appeal for them unless you're required to use them by racing rules.

Since you were looking at patriot I assume you want aluminum offshore heads- there are plenty of options available for that. Also with that cam id get a 195-210cc port not a tiny 180cc port.

I don't know where you got your info but the Dart SHP heads I have been buying have been aluminum !!!!

[prostcelica]

Here is the link to the heads I am looking at. Being that its going to be a street car isnt a 200cc head to big?? I told Comp what I was doing and thats the cam they recomended

Hey CNC block: Do you like the SHP heads??

Dart 127122 - Dart SHP Special High Performance Cylinder Heads - Overview - SummitRacing.com

[prostcelica]

Thanks for the info 2wldr4u. I think I would just spend the extra 200$ and get the AFR's though.

[vinniekq2]

AFR 180s will support 550 plus Horse power,how much HP are you planning on making?

[ap72]

Originally Posted by vinniekq2

AFR 180s will support 550 plus Horse power,how much HP are you planning on making?

on a mild 350? for that much power if bet looking at the 210s.

[hpete]

9/12 issue of car craft has a low buck aluminum head shootout. The dart heads have 200cc intakes everything else has 180, if your going to port them all of these heads are promising.

[vinniekq2]

If you have heads that flow 250 plus cfm on the intake side with a 75-80% exhaust flow,for normally aspirated engines,,,,I would go with the smallest cc intake runner that gives the flow numbers I want.This keeps the intake velocity higher on a smaller engine.
on a mild 350 I would consider modified vortecs first.any aluminum head that offers CnC machined,flow tested aluminums next,for a race car,go with specialty heads and custom porting.

[ap72]

Originally Posted by vinniekq2

If you have heads that flow 250 plus cfm on the intake side with a 75-80% exhaust flow,for normally aspirated engines,,,,I would go with the smallest cc intake runner that gives the flow numbers I want.This keeps the intake velocity higher on a smaller engine.
on a mild 350 I would consider modified vortecs first.any aluminum head that offers CnC machined,flow tested aluminums next,for a race car,go with specialty heads and custom porting.

Flow numbers aren't everything. Using the smallest port will result in severe choking at high rpm. There are ways to corectly size the port and the valve for your intended usage, always using the smallest is not one of them. You can get 250cfm out of ported stock castings, that doesn't mean they're good for performance.

Btw excessive velocity is just as bad as inadequate velocity if not worse.

[prostcelica]

I wont be turning the motor past 6500 Tops!!. Probably put a 6000 pill in my msd just to be safe. This will aslo be a street car. Ive read you really dont want to use anything above a 195cc intake runner on the street. Also seen many people say 180 runner is perfect for 350 street motor. I talked to 2 people at AFR one said use the 180's for sure. The other said Because of the weight of my car (2500#'s) he go 195's. Being that im a cheap a** I considered getting a cheaper set of heads(still want decend quality) and port and polish them.
I would like to make 450hp but still have a reasonable amount of tourqe.

Any head suggestions would be appreciated. I can get a set of AFR streets to my door for 1715.00 USD. If I could get a set to my door for $1200 and port and polish and achieve that 450hp goal I think thats the way I would go. Im in Canada btw

[vinniekq2]

stock 292 angle plug heads can make 450 HP with a decent camshaft.My 67 Camaro used GM cast iron heads,solid cam,850 holley,ran high 11s @ 114,car weighed 3600 ish with me in it.

The afr heads can make more power with less cam,you do the math on cost and drive ability.