cracked vortec heads - use original LB4s?

[Quickstop [UK]]

I bought the Syclone with a blown motor and got a used motor from a 1999 Blazer. It turns out that the Blazer has two cracked cylinder heads.

They are not salvageable (machine shop took a look) but the LB4 heads from the original might be ok. Given the cost of the heads and shipping to the UK, I'm thinking about using the LB4 heads on the vortec motor, the reverse of what we normally do. This would be a temporary solution until I can source some heads at a reasonable cost.

What do you guys think?

 

[RealFastV6]

Re: cracked vortec heads - use original LB4s?

On the upside you wouldn't have to do the conversion on them or the intake.

If L35s and Vortecs aren't available there then I guess you do what you have to do!

 

[bezerk]

Re: cracked vortec heads - use original LB4s?

i have a set of ported vortec heads, converted

 

[Quickstop [UK]]

Re: cracked vortec heads - use original LB4s?

i have a set of ported vortec heads, converted

Godverdommuh.

 

[bshaw1979]

Re: cracked vortec heads - use original LB4s?

i have a set of ported vortec heads, converted

I thought it was the lower intake you had to convert to fit the vortec's and not the heads?

 

[Quickstop [UK]]

Re: cracked vortec heads - use original LB4s?

You have to drill the vortec heads to match the bolt pattern of the original SyTy intake.

 

[2kwik4u]

Re: cracked vortec heads - use original LB4s?

You have to drill the vortec heads to match the bolt pattern of the original SyTy intake.

And the Intake needs material added to it to cover the ports properly.

So both

 

[Quickstop [UK]]

Re: cracked vortec heads - use original LB4s?

So both

So that aside, this is a viable option? I thought that the compression might be slightly reduced (good for a turbo) and I wasn't sure how the newer cam would respond to the older heads/flow.

I have two valvetrain setups and am not sure of the compatibility. I'll need to see what the rocker ratio is.

The LB4s were on an engine that hydrolocked - they still may be unuseable. I know a couple of the valves are bent. Could I swap the valves out of the vortecs and into the LB4s or are they different again?

 

[2kwik4u]

Re: cracked vortec heads - use original LB4s?

You're getting above my pay grade with those questions.

I would think that it would all bolt togethor and work, but I really don't know enough about what happens below the intake to offer any real good advice there. I'm sure someone here does though.

 

[Quickstop [UK]]

Re: cracked vortec heads - use original LB4s?

You're getting above my pay grade with those questions.

I would think that it would all bolt togethor and work, but I really don't know enough about what happens below the intake to offer any real good advice there. I'm sure someone here does though.

I think it probably would be fine as well. Seeing as it costs so much to get replacement heads, looks like this is going in until the LSX can make an appearance. :rotf:

I guess the tune will be a bit different but when isn't it?

I hope the heads are salvageable.

 

[bezerk]

Re: cracked vortec heads - use original LB4s?

I thought it was the lower intake you had to convert to fit the vortec's and not the heads?

both

 

[Quickstop [UK]]

Re: cracked vortec heads - use original LB4s?