mrm2083

Hi, I don't have speed boat, I have a mastercraft wakeboarding boat but looking around you guys seem to know alot more on this topic than the ski boat forums. I use my boat in saltwater and the cast iron manifolds on the engine are rusting alot after only 130 hrs and 7 months, and i flush with saltaway after every use. It has a 5.7L indmar engine, which is a vortec 350, it is closed cooled but raw water still cools the manifolds and risers. I've been looking for something more salt friendly and the eddie marine thunder manifolds seem to fit the bill. My questions are, will they void my warrenty? Are they better than using stock ones? Will i have to remap my ecu, im not trying to get more power, just need them to work correctly. Any other manifolds you recomend?

Thanks,
Manny

BY U BOY

they should work great for what you want to do. you do not have to do anything except bolt them on. as for warr i don't know the answer to that question.

oldandtired

Stainless Marine also makes a nice setup for small blocks and has a great warranty. Just make sure that when you order whichever manifolds you get, that you get the brackets that are specific for your application so that whatever accessories are attached to the manifolds will fit up correctly. If you have a switchable (captains call) system, make sure that they are correct for that as well. Anything is better than the cast iron manifolds. You do not need to remap the ecu.

Rene

the duke

I like the stainless marine too. 5 year warranty can't be beat. You have to see if they make risers that will bend down to meet your exhaust that run along the floor to the transom. Calling Stainless marine direct should give you that answer. If they don't have it stock they can probably make them. There should be no reason that these exhaust void your warranty, but just looking at it should tell you. Also your MC dealer should be able to tell you.
http://www.stainlessmarine.com/
305) 681-7893

JLAY

I have the eddie marine aluminum manifolds with the stainless risers and they work great plus they are much lighter.

mrm2083

Does anyone know what the policy is for these engines and aftermarket manifolds. Is it like car engines where you're warranty is only void if the defect is caused by the aftermarket part? One last question, since aluminum and iron (the block) have different expansion rates, would this cause leaks?

the duke

I'm not sure how Indmar writes their warranty. All of the companies write them differently. You should have a copy of it that came with your boat.

As far as Aluminum to Iron heads, no there will not be any leaks. Put them on, run teh boat the first day, and then re torque them, and you should be fine. Mine have not had to be tightened in the last 2 years.

awsomethunder

anyone know which manifolds make the most power on bigblock?

Lofty

We have the stock indmar replacements... cheap!

We also have RMI for small blocks, around $900.

Call or email for my best pricing.

Fionn
925.952.4240
[email protected]

PS: Can't answer you warrenty question either but my guess is that ANY aftermarket exhaust will void the warrenty.