Griff

550 hp with how much boost from the 177's????

phragle

iTrader: (3)

going to a 468 with a little higher than 7.5 would do it with stock boost wouldnt it??

Griff

The 250's are not going to add 100hp.

If he was running 5#'s with the 177's and bumps it to 7#'s with the 250's, I'm guessing he'll see about a 50hp increase.

indysupra

iTrader: (3)

I personally don't think you will loose 100 hp going from my 540's to your 468's. I actually think if you ran your 177's hard and ran the 250's for the same distance hard the power pickup will be even greater because I bet the overdriven ratio on the 250's is much better.

JRider

iTrader: (1)

What kind of carb setup? Single or dual? What I see is lower blower speed and less heat. 420s would have definitely been better

Hopper

iTrader: (1)

4 lbs of boost

Hopper

iTrader: (1)

I think they are dual 1050's less heat for sure.. I guess at the end of the day they will be better then the 177's if it wasn't such a pain in the ass I would pull 1 engine out and dyno it with the bigger blower

Hopper

iTrader: (1)

I know that was my original plan... but the boat is in storage I need to get it out get them swapped before I commit on selling 1 to you just to ensure I have no issues.. do you need the carb and intake as well? they were all just rebuilt 20 hours on them..

Hopper

iTrader: (1)

thanks for wrecking my fantasy Griff LOL... I agree with you the more I think about it... do you think 7lbs of boost would be ok on those engines??

getrdunn

iTrader: (7)

I think you'll be close but don't surpass the limits off respectable boost to achieve something that will jeopardize a melt down. I'd still say you'll be close to your goal but find out how much diff in power btwn the 250 and 420 mb. I didn't think there was a huge difference other than being able to spin the 420 a little more as it runs cooler. I may be out to lunch on that one though.

I do know rookie was over 600 hp with na 468's so....