I'm thinking about putting a set of keith eikert lightning manifolds on and trying to decide how much (if at all) they will help with performance. I've got a 454 that I'm putting 781 heads with bigger valves, gasket matching and bowl blending. Have a mild cam (don't remember specs mid 550 lift), dual plane high rise intake, going from a qjet carb to a 750-850 holley and adding crane gold roller rockers. As of now I have old stock manifolds. They aren't leaking, but thinking they are not helping the cause. Will adding the ke lightning exhaust with the mods I'm doing make any noticeable difference?

The boat is a baja 235 force.

I did some research and didn't find much on the ke lightning exhaust.

Thanks

KE Lighting exhaust headers do a great job on a big block marine engine. They flow much better than stock exhaust manifolds and they will not leak water at the riser flanges like a lot of stock manifolds eventually do. As for power the increase to an average mild engine will probaly be around an increase of about 5% generally in power over stock manifolds so if your engine turns out to be lets say a 425HP big block you would probably expect about 21-25 more horsepower or so and in a 23 foot BAJA i would expect that might be 2-3 mile per hour increase but the biggest benefit would come from increased torque in the 2500-4000rpm range which will probably result in better acceleration and cruising speed performance and efficiency. If the engine is a higher horsepower base engine or increased in the future with more cubic inches, bigger camshafts, induction and improvements then the header benefit will increase accordingly. Besides all these possible power improvements, lets face it they look much better and make any performance marine engine look more like a high powered engine and sound cool too!.
If their in your budget and you can add them, then by all means do.

Best Regards,
Ray @ Raylar

Thanks Ray for the detailed reply. I do plan on adding a blower in the coming months and plan on building a 540 over the winter so I'm sure they will help long term.

Thanks again.

Cp

you have done a lot to this 454. overall you are goung to see about 100 hp gain over the stock 330 you started with. blower? i dunno. this is a cast piston cast crank engine. now you are thinking big inches for next year. if you are doing that, make sure the blower is adequate for the 540, but dial the boost down to 5 psi for this engine. same with exhausts. they are a major expense and MUST do the job for the next phase of this build-up. i am not saying they won't. but you need to do some homework. the 781 heads? they stay with the 454 as a spare engine or to be sold as complete engine. large ovals on a 540 is worse than peanuts on a 454. stock iron rect ports need work to let a really big motor breathe. and you are gonna find out just how much fun porting iron heads is. one of biggest advantages of alum heads is you don't have to spend forever with a die-grinder in your hand to get results. next thing you need to consider is hyd steering. big power in a small boat is scary and dangerous if you can't make is go where you want it to...

Derek, I agree with buying stuff that will work for my future build. Everything I plan on doing I'm trying to make sure it will also work on my future plans. To an extent anyway. The 454 will stay as is minus exhaust so I have a spare running engine. My buddy has a lead on blown up 502's out of air boats for cheap so I will start from there and build up. The exhaust I'm looking at is supposed to be able to support 750 na hp (from what I've read) so that should be able to cross over.

With in a year or two I hope to find a 29 fountain fever single minus the motor and at that point I can sell my Baja with the 454 and already have a 540 to drop in the fever. Thats the plan anyway.


Thanks for all the help guys! I got into the powerboats last year with this Baja and really enjoy it. With out this forum I would not know 20% of what I know (its not much..lol) after reading this site for the past year.

Cp

I think the ke exhaust I mentioned might be misleading as I can't find anything on the ones I was looking to buy.

Here is a link to the ones I was looking at buying. They don't look like the ke full length runner that comes up when googling ke manifolds.

Any info on these?

I think this may be the link to the headers you are referring to:
http://www.keitheickert.com/c-444-bi...g-headers.aspx

Remember KE sells and distributes several manufacturers marine exhausts and headers as well as selling their own specific headers and designs.

Best Regards,
Ray @ Raylar