I have a 1987 chevy 350.
I will be useing holly pro injection.

I belive the heads on the engine have 197 valves
I have a good set of 2.02 heads off of
a 400 chevy.

I have had this debate with a few frends
and cant make up my mind on what to do.

It was also sugested buy one person that I
get a head with even smaller valves.

His reasoning is that the smaller the
valve the lower the rpm will need to be
to produce peak horse power.

Vehicle is a fj4o with sm420 and
3 speed transfer case 4.10 gears 35 inch tires.

Thanks..

Small valves/ports are supposed to give the charge air more velocity at lower speed, so it will fill the cylinder better = more low end torque, but it will run out of power sooner than the bigger valved engine will (at hi rpm).

I'd use the 1.97s with the projection, and save the 2.02s for a big 4 bbl. motor

first of all dont go projection:

http://www.pirate4x4.com/forum/showthread.php?s=&threadid=27679&highlight=projection

then go big intake small exhaust for low end torque.

what cam?

stock cam

from what I have read the pro injection
will be ok as long as I dont modifie the
engine to much..

ps I probubly will keep a one barel
carb around in the spares box just in case.

Projection's run rich so you might want to put in a rv cam, just keep it milg and built for grunt not ponies.....

Personally I would go with vortec heads! they are really cheap (well for heads at least) and better all around then either of your choices. I think you should be more worried about port design then valve size. Also came design will be a bigger factor also. Get something with lots of lift and lower duration. I would call the came manufactures they are very helpful and obviously knowledgable.

agree with port comment
the valves can be huge as long as port matches your requirements

I wouldn't use the 400 head, they are notorious for cracking, especially around the steam holes. Its rare to find of 400 heads that aren't cracked.....:skull:

vortec head is a good idea

I know that they have a very straight
passage for the air to travel.

this brings up another question
would a 194 head that has been ported
be better than a 2.02 head.
as far as air flow ?

Um, isn't a 350 Chevy the MOST DOCUMENTED engine ever created????? :rolleyes:

2 cents worth, stock Vortec heads, single plane port injection, GM TPI ECM.

Squash

Originally posted by Land Crusher
vortec head is a good idea

I know that they have a very straight
passage for the air to travel.

this brings up another question
would a 194 head that has been ported
be better than a 2.02 head.
as far as air flow ?

Vortec heads have small valves and out flow every other SBC production head except the fast burn. Even better then the old Bow-Tie 2.02 heads