Big block or Small block?

[Verytricky]

I am trying to get a very reliable 650hp out of a V8.

I have twice blown up a volvo (GM) small block on the dyno table!


So - apart from determining I am crap at working engines - I have realised I need advice. I was told it was because I was using Mexican blocks, now I am told this is not actually true.

So my thoughts are to start off with a two bolt block and then turn it into a four bolt block.

Next step?

Or are there reliable engine tuners/builders that can be recommended?

I want a V8.
Small block preferable, but Ally head big block would fit ( just! )
I want fuel injection, not carb.


Thoughts?

[Jango]

650 HP from a small block can be done, but realibility is another thing. An engine builder Friend of mine has a Drag racing car with a 327 chev producing 800 HP @ 9600 rpm and 550 lb ft torque, NATURALY asperated. He maintains 2 Bolt Blocks are Stronger than 4 Bolt, but He adds after market 4 bolt caps w. "splayed" outer bolts.
Keeping in mind that Drag race Engines run only a few seconds and are shut down, I would only consider for marine use, a Large displacement Big Block i.e Offshore Race type Engine.

[Verytricky]

More info.....?

[stonebreaker]

This site will help you: http://www.bankspower.com/twin-turbo-products.cfm

[Verytricky]

Hmmmn. impressive, but I dont think I would race with that...

[azs]

Sprintcar race engines are smallblock with that sort of hp. They focus on lightweight componentry as well, with ally blocks and heads, and lots of titanium. See if you can get on to a Sprintcar engine builder for some tips.

[Jango]

There are many people here in the USA who can supply Big powerful marine Engines. Take alook at : http://www.bakerengineeringinc.com/PEOffshore.html

Google: Offshore Racing Engines

[Frosty]

I think you slightly missing the point . Mr tricky needs 650Hp continuous to drive a boat for an hour or more.Thats a bit different form a drag at what 5 seconds. Infact what ever race application you can think of.

It would be like putting your motor on a dyno and giving it max RPM-- max HP-- for an hour.--- Oh with out a rebuild every week!!!

[Jango]

That's why I suggested a Big Block with alot of cubes. Offshore racers run for hours with alot more than 650 horses

[stonebreaker]

Hmmmn. impressive, but I dont think I would race with that...

Well, I didn't mean it to be the only answer. I don't think Gale Banks does offshore racing anymore, but that's how he got his start, and that's where he designed his turn key engine packages. I know he prices them like they should last forever!

[Verytricky]

I think you slightly missing the point . Mr tricky needs 650Hp continuous to drive a boat for an hour or more.Thats a bit different form a drag at what 5 seconds. Infact what ever race application you can think of.


Egg Sack Leigh!

First off, the specific race is Around Britian. This is 10 days x three hour legs per day. Sprint car engines are completely useless. It is too much even for some outboard modded engines, which are estimated to last 25 hours between rebuilds.

I need an engine that is reliable for a minimum of 100 hours WOT without a rebuild.

Based on my racing experiance with a 320hp V8 ( rev limit at 5050 RPM )10% of the time will be between 4500 to 4750 and 85% will be from 4750 to 5050 and 5% will be below 1000RPM. There is almost zero time between 1000 rpm to 4500.

There is also the stress of hopping out the water, and back into the water..

[stonebreaker]

Hey, here's one: http://www.falconerengines.com/prod02.htm

[Jimbo1490]

Tha Falconer is a great engine. I have followed the fortunes of the engine and company since the early 90's when they intended to market it as a low cost replacement for the lower HP marks of the PWC PT-6 turboshaft in the Beech King Airs. They did not forsee the coming of the Walter turboshafts from Czechoslovakia, which gave operators a turbine choice that was as cheap as their piston engine choice. A single PT-6 costs the same as two Walters + two propellers, which is about the same as the Falconer, so most operators opted for the proven reliability of the turbine option over the Falconers, despite the greater efficiency of the Falconer. Thus Falconer now markets their engines for marine applications.

Jimbo

[Michael1]

Having spent a fair amount of time hanging out with the offshore people, don't waste your time trying to build a reliable 650 hp small block. That's an exercise in futility. Get yourself a 572. It is available with aluminum heads provided you put in a closed cooling system. Put in Inconel valves for reliability. Make sure the valve guides are machined loose. Have the bearing clearances on the loose side, too. Run 30 wt. oil or heavier, and be sure you have plenty of pan capacity (12 quarts). Use a good quality marine roller cam, and roller rockers. Get some quality headers, such as CMI. Keep the RPM down near 5000, and you should have no problem running 100 hours without rebuilding.

Michael

[Verytricky]

Thanks.

It looks like I am heading towards a big block with ally heads and a closed circut cooling system..

BTW, the Round Britain is off the cards for 2008 as far as my involvement, I have withdrawn from the event.

BUT

I am looking at a few distance records, which I think I can get in 2008. I will probably start off with the Isle of Wight record, and move on from there. I will need a similar Hp engine, just running it for shorter runs than the 10 day event. The longest will probably be the 17 hours for the Gibraltar to Monte Carlo run.

[mongo75]

No replacement for displacement! With a bigger engine you don't have to push it as hard, so reliability is definitely on your side. Or how about a diesel? Yes they are heavier, but modern diesels can be built for tons of torque and hp to boot. Plus fuel economy is on your side.