Hp500 clone with 3-4lbs non intercooled boost , want to keep it under 600hp?
 

Just wondering if I have to worry about drive reliability, trying to keep it under 600hp.
Have a 502 40 over, HP500 heads, custom roller cam ( bit more lift and overlap but little less duration than HP500) and Drake ( designed by KE, individual runner to the riser ) manifolds dry to the transom.
and want to add a Merc 575 blower set at roughly 3.5 - 4lbs boost.
I am thinking that would be around 575-600hp but just wanted to check with you guys.
I am easy on the sticks and dont fly the boat but also dont want to be breaking Bravos.
If you wondering why its because I already have everything so it wont cost me anything to do
and I LOVE that whine,LOL....

You will have to baby a standard Bravo to make it live. I would guess that you will be right at 600hp.

Thanks!

you basicly will have a 575 .... with less cam, my guess would be that your going to be more in the 560 range.
the 575's i help with dynoed 601 and 608, i feel the smaller cam is going to put you down a bit from stock 575's.

i take i your going to use the Merc EFI also? if so i'd just get a roller replacement 575 cam while your at it so it runs right with out having to retune.

you wouldn't regret getting that style of cam, those motors sound all sorts of pissed off!

Just be easy on the takeoffs.

Also need to spend the money on an intercooler. Will give you a bigger safety factor.

Actually I believe the 575sc had a very mild flat tappet cam, so you should be more than 600HP. I am not a expert on blowers, but it should add about 100hp from were you are at now.

That is correct, the 575s have a very mild flat tappet cam.
My roller cam was custom ground to make same power as HP500
roller cam but with no reversion problems.


Dont really need intercooler at such a low boost level..

Its gonna be carbed...

Here is what engine/cam sounds like , this was in my last boat
before I swapped engine into my new boat but engine has stayed the same.
http://www.youtube.com/watch?v=fl0vGAiqkLM

Who did your cam?

http://www.midwayperformance.com/predatorcams/

We talked for over an hour to get me the right camshaft for me,
Very happy with the cam. I know everyone here uses Bob but I needed the cam right away and they made it and got it to me in under a week .

Maybe we're not on the same page, when you say 575 I'm thinking 575 SCI. Yes they do have a flat tappet cam but it is much bigger than what your running in duration.
By the near stock sound of your motor in that video, on a guess I'd say the 575 cam is at least 10 more degrees @ 0.050 intake and exhaust than what your running.

dont know the specs on the supercharged 575 cam so I really cant say..
Just have read on here that the cam on them is on the small side.

Mine are:
gen6 roller
580/590 with 1.7rr
[email protected]
230int 236exh 114lsa

Regardless it doesnt really matter to me as it does what I want it to..
:)

Thank's everyone for your responses!

i must admit your cam is closer in duration than i thought, the 575SCI is - Crane 13h000060 240*/240* @ .050 .559/.559 lift
adv duration 300/300
grind # h-240/329-10 t1.2

don't get me wrong i'm not saying it won't work well with that cam because it will real well. the blower will like the 114 C/L, good luck with the build and if you dyno it be sure to post up the results!

Thanks, I dont know if I will dyno it out of the boat but
will probably use mph to gauge my increase, I do have a
wide band A/F already installed to help tune plus fuel pressure and
vacuum/boost gauges.
Right now my best was 69.8mph@5200 with a 4 blader ,boat weighs about 6000 fully fueled which it was for that test run but I have lots of slip in the midrange,(high x dim)
Im going to try a 5 blader plus the blower, hoping for some solid increases in cruise speed more than anything and 4-5mph on top end. I also just bought some 28" long K-planes for added stability.
Should be a fun summer next year..