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Question on exhaust reversion?
I have a new cam I was about to run and i have been told to be catious of exh reversion.
I dont want to wast a motor.

I was going to run stock the manifolds

Cam spec .544 In .547 ex. durration @50 226 In 236 ex.

I was going to get new edelbrock heads and intake.

If I have to get a new exhaust which would be a good choise?
330 trs drive
Tom

Boatally Insane

iTrader: (1)

I wouldn't run the stock manifolds with that much duration.
I was just recently exhaust shopping and the cheapest NEW manifolds I found were Eddie Marine with a long riser for $1575.00 at www.diamondperformanceparts.com there is a lot of reasonably priced used stuff out there also just make sure you have it leak tested.


Doug

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i was thinking of going with used exhaust.
can i just use any performance exhaust? just extending the hoses?
Do i have to run a dry tail pipe? Is it that much better? Or necessary?

I found used manifolds can i use any style as long as it has casting around the manifold?
Do some systems last longer? (fresh water Mi.)
thanks

monstaaa

i have some used exhaust, cmi uni top's , stellings logs, merc logs, call me 516 799 6029

Boatally Insane

iTrader: (1)

You need to run a longer riser than stock to put the water in the exhaust stream farther away from the engine. Just lengthening the hose would not help this at all.
Completely dry exhaust is very loud.
I would think that almost any aftermarket manifold style exhaust system with a long riser would work good and last a long time in fresh water.


Doug

NOBODY

Just curious, anyone ever had a motor fail from rev . probs. If so can you explain in detail what happened to the motor and in what order it happened in. I believe even if you had a bad case of rev. it would take quite a while before you had motor probs.

Vinny P

A major factor causing reversion is lobe seperation. What is the lobe seperation on that cam?

BOATING ON A BUDGET

lobe seperation is 112.0
comp cams 11-236-4 xm 270h-12

BOATING ON A BUDGET

Can I put risers on and just dump right at the end of the pipe aprox. 6' away from the tail pipe.
Does that make the motor much louder?
Would that solve the reversion?
Do i have a potential problem?

blue thunder

I ran a cam close to that with stock center rise exhaust 226/234 on a 111 lobe angle. After starting engines on the shop floor I removed the risers and found water pooling in the manifold. Couldn't afford two sets of exhaust at the time so I bought Imco stainless steel riser and bolted them on my stock manifolds. Moved the water back several inches which seemed to do the trick. They also claim a 10hp improvement due to the sweeping elbow. I since sold those risers to an OSO member and bought headers.

As far as engines failing due to reversion, I had an exhaust valve shatter one time which I concluded was embrittlement due to cold water quenching after a hard run. Never sure.

BT