Hey guy i am going to be getting a 350 and redoing it! Now 350 heads are 1.94 and 1.5 correct me if i am wrong. But what do you guys think of porting and polishing them to be 2.02 and 1.6? Will they work good or should i buy new heads?
thanks
kevin

 

Depends which heads they are.

 

there are some really good videos that i just stumbled across that might answer your questions. go to www.enginevideos.com or you can get them at racingjunk.com

the name of them are power building videos. he has a couple different titles.( rotating assemblies, nitrous, supercharging,,, and heads porting and valve train)

answered alot of my questions....ad gave me alot of ideas for future builds

 

Ok i will check them videos out sometime tonight! But lets just say that i get a 350 from like a camaro in 1968-1971?
thanks
kevin

 

there are a lot of really good castings thru those years. but even at that, just putting bigger valves in heads dont always make them flow any better. Not without some port work.

 

I would have a pretty good performance shop by me do it. Theny have their own funny cars and stuff so i think they will do a good job at it but is it a good idea? will they work about as good as new 2.02/1.6 heads?
kevin

 

Again... depends which heads they are.

 

It is not cost effective to pay someone else to port a stock OEM GM SBC head.
The $$$shop labour time required$$$ to fully port a OEM head to flow near a decent aftermarket head will be higher than the cost of a new aftermarket head.
A simple pocket port job "street port" "stage 1 port" will not get you up to a the flow of a aftermarket head.

The only way to do it in a cost effective manor is to do all the porting yourself and then have the shop do the valve job and other required machineing.

Be sure to get a accurate total cost estimate ( with all real labour costs, machining and parts ) before you go ahead and start this.
New high quality aftermarket high flow 2.02x 1.60 aluminum heads can be had for less than $1000 (US)
eg:
http://store.summitracing.com/partde...5&autoview=sku

What is the casting number on the cylinder heads you're thinking of having ported?

 

Hey thanks man ya i will run down to their shop and see how much they would charge for it! Bc i figured an aftermaket will be better but i thought i might be able to save money and have good flowing heads.
thanks
kevin

 

Hey guys i have found a motor that i am looking at! It is a 350 crate motor from the mid 90's he said. What do you guys think of them heads?
thanks
kevin

 

get the casting number from under the valve cover and look it up.
www.mortec.com
Most of the 350 "crate motor" heads are not worth playing with at all.
Exceptions are vortec (062 906) (350HO 330hp) and corvette L-98 aluminum (113). 350 "ZZ4"
All other heads than come on 350 cratge motors have little or no performance potential.

I get the impression your knowledge is very limited in this area.

 

Yes i am 17 and i think i know what i want but now im trying to some info on this stuff! Here is my plans!
350

• bore .30
• 2.02/1.6 heads
• 11.1 compression
• 800cfm carb
• performer dual plane intake
• small tube headers with muffler
• high performance cam with around .600in lift on Int and Exh

Something like that and hopefully that will put me around 430-450 at the crank. Then hopefully 360+ to the wheels.
thanks
kevin

 

If it's a gen I crate motor (hecho en mexico), the heads are pretty much the worst you can get (then again any 76cc 1.94/1.5 smog head is pretty awful). I have a brand new pair I took off a crate motor and they are not worth running. Super low compression and really nasty lightweight castings. You can't really port these heads, there is not enough material there. If you do have a gen I crate motor, do not waste your money putting bigger valves in the heads. Start out with different (or better yet aftermarket) heads

 

Sounds good, mabe a 750 cfm carb. and little smaller cam would help. If the heads are not vortec you would be better off buying after market heads.

 

too much cam for nearly any stock style head, too much carb for a 350. Way too much compression for iron heads. I would suggest you do some reading and study some proven combos.

 

Well how else would i get that much hp with a 350 and not making it a 383?
kevin

 

You sound like you need to do a lot more research before you start building engines. A lot. Also, is this car going to be daily driven, or a track-only car? Just asking, because if 450 fwhp is your goal with a carb, you're gonna be sucking down gasoline like a fat kid chugs soda.

 

Ya its my every day driver but i am also getting another beater from a guy. Im having a performance shop build it im just going to buy the parts.
kevin