[ap72]

Originally Posted by 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

If your redline is 6000 rpm then you have the wrong cam. For that rpm on a 350 a 180cc runner is about perfect. A cam with about 225 intake duration (.050" hyd) will be about right.

You need to pick a concrete target and have all your parts work towards that goal, not just slapping parts together.

BTW taking about 10cc's out of junk yard vortec heads along with a good valve job and stock valve would actually be about perfect for your goals, and can be done for less that $500. Much less if you're resourceful.

You're making reaching your goal much more complicated than it needs to be.

[CNC BLOCKS NE]

Originally Posted by prostcelica

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

Where can you buy AFR's for 1020.00 ???

[CNC BLOCKS NE]

Originally Posted by vinniekq2

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

A 180 runner head 550 horse are you serious!!

[CNC BLOCKS NE]

Originally Posted by 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

I have a set of the 200 coming this week but here is some info on the 200's

ATK HP ENGINES / Eric Weingartner Dart SHP 200CC Test - Yellow Bullet Forums

[vinniekq2]

CnC,whats the confusion?

[prostcelica]

Heyyou car CNC. I wish I could get AFR's for 1020 (so does everybody I would thnk :-) ) AFR's will cost me 1720 usd by the time I have them in my hand. Do you think the dart 200cc head would be to big for 355 street car?? Also that link you posted look like it was for a 383. What do you think those numbers would be like on my setup if I did some clean up on the heads??

Thanks again for the great info

[CNC BLOCKS NE]

Originally Posted by vinniekq2

CnC,whats the confusion?

No confusion I have built alot of engines over the years and if I was looking for 550 horse it would not be with a 180 runner head.

[CNC BLOCKS NE]

Originally Posted by ap72

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.

X2

Just another guy racing a flow bench LOL

[vinniekq2]

most street driven cars dont even need the flow of a 180 cc intake runner AFR head.I use dart 227 heads on my car,its not that Im scared or unaware of what those heads can produce.Just look around at the general posts,hydraulic cams,small to medium carbs,most carbs are vacuum secondaries,lots of dual plane intakes,small tube headers,2 1/2 inch exhaust or smaller,,,,why would any of these applications need 200 plus CC heads?

[Ripper 410]

I have used Darts for years and refuse to buy any other name brand to race with for two reasons reason #1 out of the box they out flow all other competition and #2 they are truely a track proven performance head I have a set of the 230 pro1's on a 410 small block as we speak the shp series are nice for any app and I believe the dude that replied about the cast iron heads was probably thinking of the sportsmans which are still excellent heads but you won't be disappointed with any Dart head you pick!

[Cridder]

Originally Posted by ap72

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.

Remind me to tell that to the next guy i see running a tunnel ram,
i take it theres no benefit to port velosity in the late stages of valve closing.
I think someone once said "when is fast fast enough" that person should have the answer, he can tell us why excessive port velocity is bad.

[bigdozer]

i run the brodix ik 200, on 355 and 383 and for the money they real hard to beat ,run 11.80 with 355 and 11 .00 with 383 turning 6500 with both, and those are right out of the box, check them out might be something your interested in

[ap72]

Originally Posted by Cridder

Remind me to tell that to the next guy i see running a tunnel ram,
i take it theres no benefit to port velosity in the late stages of valve closing.
I think someone once said "when is fast fast enough" that person should have the answer, he can tell us why excessive port velocity is bad.

Port choke and air fuel seperation.

Look at the engines being developed now, specifically the current ls and hemi runner designs... also consider those engines will rarely see more than 5,000 rpm and spend the majority of their lives right above idle...

But I'm sure they were doing much better in 1965 than in 2012...

[cdminter59]

I have been on Comp Cams CamQuest. I went thru every HYD. roller cam they have recommended and according to the dyno results on their cams you wouldn't come close to 450 Hp with your parts. Now if you use the Dart SHP heads with a Comp solid roller XR280R, 2500-6500 rpm range, single plane intake with a 750 cfm carburetor,3.73-3.90 gears and a 3000 stall it will put out 424.1 hp@ 5500 and 436.7 lbs of torque @ 4500 rpms. With the largest Hyd roller hp was like 387 hp @ 5500 with your intake and carb. If you wanted 450 hp should have done some research and built a 383.

[prostcelica]

I went 355 because I got a smokin deal on itfrom a friend. I would like to make 450hp but at the end of the day I just want to build a nice stout street motor.