center riser or rear riser.

[foresteronw]

Will it matter if I change from a rear riser exhaust manifold system to a center riser manifold system. I want to do this for exhaust rousting room.

 

[zzzzz]

Re: center riser or rear riser.

Forester-no it won't...you'll actually be doing your engine a favor because the end rise doesn't cool the cylinder farthest from the riser quite as well...center rise distributes the water more evenly

 

[foresteronw]

Re: center riser or rear riser.

Is there any difference in mounting to the heads, I wouldn't think there would be but just want to make sure.

 

[zzzzz]

Re: center riser or rear riser.

are we talking small/big block chevy??

 

[foresteronw]

Re: center riser or rear riser.

I have a 1989 OMC 5.7L GM 350.

 

[zzzzz]

Re: center riser or rear riser.

from what i can tell it should bolt right up

 

[foresteronw]

Re: center riser or rear riser.

any tricks to getting off manifold bolts that are rusty without buting them off?

 

[zzzzz]

Re: center riser or rear riser.

soak them with a rust penetrant and walk away for a nite...turn 'em till they tighten up on ya' then soak 'em again and walk away...if you rush 'em you'll break 'em...patience is the key !!

 

[foresteronw]

Re: center riser or rear riser.

thanks a lot. i appreciate all the help. I have one final question. If my manifolds are shot, this would cause me to get water in my oil correct? They are original (1989) so they are due to come off. How can I tell if it is the manifolds causing the problem or a cracked head/block?

 

[zzzzz]

Re: center riser or rear riser.

correct...cracked manifold=water in oil...as for the manifolds,some shops can pressure test them but I'm not sure of the exact procedure whether they need to be on or off motor-call someone local you trust or put up a new post about pressure testing them also,if you're still wondering about the bolt up-buy one gasket for the center rise and check against your exhaust ports

 

[foresteronw]

Re: center riser or rear riser.

not too sure what you mean by getting a gasket for the center riser. Do you mean if I want to use the old risers with the new manifolds? I am more concerned about the manifolds bolting up to the heads, but that is a good point. I could use that same idea on the manifold to head area as well. I called around here about the manifolds and risers being presure checkes, but nobody does them around here. I am just trying to figure out how to tell were the problem is coming from without tearing apart the engine.

 

[zzzzz]

Re: center riser or rear riser.

Sorry!what I meant was to get a head side gasket for the center riser manifold and check bolt pattern...as for using old risers with new manifolds-not advisable...if we're talking original equipment (1989)..heck-they're old enough to drive !...do all new for the piece of mind...put up a post on the pressure testing and see what you get

 

[foresteronw]

Re: center riser or rear riser.

thanks for all the info.