3400 With 3.4 RWD Head Gasktets

[sanjay]

i that case, assuming a good port job, you will see gains...

exhaust would be next in line if you don't want to mess with the heads...

Exhaust, as in the manifolds?? I'm planning on using some 3500 log manifolds.

I don't mind messing with the heads but i don't want to do anything that will hurt performance or over port and kill velocity, especially when I'm restricted by the amount of air the stock cam can move.

I don't know if I'm correct but I assume that at a certain point if your heads can flow more than your cam then the extra port work is useless and probably hurt performance by bringing down velocity..

[robertisaar]

i that case, assuming a good port job, you will see gains...

exhaust would be next in line if you don't want to mess with the heads...

[sanjay]

The inlet will be opened for use with a 62mm TB..

[robertisaar]

For a stock cam, at what point is porting just too much?? As in, is there any point of doing a WOT like porting job when using a stock cam or is a simple gasket match & cleanup sufficient??

gasket match + cleanup would help, but if you're going to do it, you might as well get a light porting going on... the TB is more restrictive than the intakes, but you might see a little gain...

[95Grand-Am]

I have used the rwd headgaskets in a 3400 and I thought it worked great. As long as you have good bearings and the pistons arn't loose keep the revs under 6000 and don't plan on running it 100,000 miles it should be fine. The piston to head clearance won't be in the safe zone so you are rolling the dice. It worked good for me, It depends on weather you want to take chances. I would recomend decking the block to 8.810" and use the .060" head gaskets this close but safer.

[sanjay]

typically you want .040" or so between the piston and the head. the stock 3400 piston pops out .020" and the gaskets are .060" compressed so it's a "perfect" setup.

with the 3.4 IH gaskets you'll have .020" of clearance and will most likely have problems.


Rods stretch at high RPM's, .020" just isn't enough clearance.

Thank you. That's exactly what I needed..

May as well throw another question out there.

For a stock cam, at what point is porting just too much?? As in, is there any point of doing a WOT like porting job when using a stock cam or is a simple gasket match & cleanup sufficient??

[Superdave]

typically you want .040" or so between the piston and the head. the stock 3400 piston pops out .020" and the gaskets are .060" compressed so it's a "perfect" setup.

with the 3.4 IH gaskets you'll have .020" of clearance and will most likely have problems.


Rods stretch at high RPM's, .020" just isn't enough clearance.

[sanjay]

What would the compression ratio be? Would you be worried about piston to valve clearance with a stock cam?? Advantages, dis-advantages??

I could have sworn I've seen the answers to both these questions but after spending the weekend searching (while those of you who probably answer these questions were having fun at the meet..lol) I've yet to come up with anything.