38 fountain 1700hp
 

Anyone out there that have a side by side 38 lighting with 1700hp (850 aside), we are currently repowering and are wondering what kind of mph to expect out of it. We are hoping for 105-110. Just trying to get some feedback.Thanks

Well I think that's a bit optomistic. I know you have steps and I don't but I have 2100 HP (1050 a side) in a 40 footer and the best we can do is just barely knocking at triple digits. I'm sure some other beak guys who have your exact setup will chime in.

what year fountain?
assuming you have the twin small steps, you should be in the ball park of 105+ with a true 850/side. You will have to be spinning some high rpm with the right props though.

It's a 2001 and currently has Orlandi power 500 efi with a true 647hp a side spinning 5600 with untouched 32 bravo ones. It will run 88- 89 mph all day with 3 people. The boat has the twin small steps and we plan on spinning 6000 rpm. With the addition of 200 hp per side and IMCO drives to hold the power we are hoping after some fine tuning of props to be over 105 mph.

I have a 32' with 830ish per side and it won't do 110! 104 is best its seen with 32p props

A friend of mine had a 2000 38 lightning with 900hp per side and saw 108. He had -2" shorties and I believe Maximus props with some cut off the diffuser ring.

the imco drive will probably eat up all the extra H/P from my understanding of those who put them on...but do hold up well...

Seems to be a little debate on the IMCO loss but I still would rather go 100 in every poker run than 105 on the first leg and being broken after that.


Matt

Yea the SCX's are going to scrub a decent amount of mph off

Judging by what you run now, and the power you are looking to add I think 105 is pretty optimistic for sure. If you just added the power and didn't touch the drives I would say you are going to be right around 100mph. With the imco's in the mix it will put you below the 100 mark. Will cost alot to get the imco's dialed in just to midigate the speed lose, and may still be 5mph slower then your current drives. Tryin to find the thread, but there was a guy on here with a 38 that ran 105 with 900 a side, and fell below 100 after putting on the imco's. He had to spend big money on props and spacers to get it back to 100-101

Had a 2001 38 with the bigger steps with 900 per side 2" shorties Imco SC's 5 blade 32 pitch Maximus and can promise it ran ran 102 any day and right conditions it ran 106. The best I ever saw was 108.
Still have props and cav plates if anyone interested.

Hard to say how the boat will react, and the set up is obviously key. The IMCO's take more power to turn then a bravo, but with X changes and prop options it may be able to be midigated at that speed bracket. I remember reading the 35 exucutioner thread at Reggie Jr's shop, and he went with the IMCO's, he was in the mid 120's, but they said there was alot left on the table with the IMCO's, and he would pick up a significant mph going to 6's.

boat should break 110 @6k. hydro p5 works well. faster then the max, as it wasn't designed to surface. set up an early small step w/700 hp 103.

Sounds like your talking about Eric's 42. He had scx-4 I think and swapped out for 6s. Still waiting on results of that. Also it's Reggie 3 shop.

You are right it was a 42, and yea Reggie 3rd is what I meant. They changed there name too, it was RFM, I believe its called R3 Marine now.

With that said, Michigain Matt, you should hit Reggie III up on facebook and ask him what he thinks, and if he has any advice. He is really good about responding, may take him a minute but he always responded to me

Why couldn't you spin lower RPM with higher pitched props?

I agree. Depends on build and where dyno says power is. 850hp at 5700 is the same as 850hp at 6400 unless I'm missing something. Prop for peak power

Yeah real fast marine still exists as a company he said but started R3 custom marine.

Was talking to a buddy that has a 35 cafe racer on saturday, when he went from Xr's to imco's he said he lost 8mph.

Thanks for the feed back but I am full steam ahead with the project, so I will keep eveyone updated