I'm putting together a motor for an 83 I purchased a while back and since it's a mish mash of parts and pieces, I wanted to ask the experts for some clarifications.

350 block, Canadian from 86.
I'm using 906 Vortec heads with a vortec carb intake.
I will be using new valves and pushrods. The springs will be reused.

the questions then are:

1. These heads currently have 1.94 intake valves. Would it be worthwhile to have the heads modified to accept the 2.10 valves?
2. Since this is not really going to be a "drag" car, I'm going with the cam that works with the vortec heads without modification of the lift. Is this going to be a problem down the road?
3. Will stock pushrods work or do I need special length pushrods? And if I need special length, what length would that be?

Thanks in advance for the help

 

1.) No. Cut for 2.02. Tops.
2.) You're limited to like .460-.470" lift. Heads are going to the machine shop anyway, just have the guides cut down and machined properly so you can get what ever cam you see fit.
3.) Check pushrod length after it's fully assembled to verify pushrod length. You may or may not be able to use stock length. Probably going to be alright, but again, double check.
4.) Don't reuse the stock springs. Stock valve springs are terrible for pretty much anything car related and would, in no way, be able to control the valves on any aftermarket cam. Buy the valve springs that the cam manufacturer recommends for whatever cam you end up purchasing.

 

Stekmans got the right idea for you here on the all of it. I would go one step further to say that, if you are not making a race car I would save the money of installing bigger intake valves. You should be able to reuse the stock ones and save a good amount of money on the machine work and valves to spend it on other areas, like roller rockers or a cam, etc. 1.94s are just fine for a steet driven 350, in a vortec package.

 

Yep, I agree completely! : )

 

Thanks for the responses. I would reuse the valves but there is some scale rust in a couple of chambers and on the valves. No pitting, just where water got into the wreck so I thought I might as well replace the valves and have the heads cleaned up and checked. While doing that I thought I might as well do some of the recommended head modifications (larger valves). One article I read, without cutting down the guides, made 400 hp+ and since this isn't a "race" car, but a hotter street daily, I thought I might save a bit.

I'll make sure to replace springs when the cam goes in.

 

Where is the rust at on the valves? If it is surface pitting on the head of the valve where it faces the combustion chamber you may be able to clean them up and use them. Either way, the valves are really the cheap part, the machine work to go to the bigger size is expensive. I wouldnt make that jump on those vortecs. I honestly think that with the right parts combination you get to nearly that horsepower without messing with bigger intake valves.