power to weight

cosworth mirage · 25-04-2009, 01:41 AM

inboardpower im looking at different engine and drive,s around 300-400hp but i was looking for some advice on the weight of different setups
the boats narrow and i think would suffer from to much weight.
is anyone using chevy ls1 or ford modula 4.6-5.0 wth alloy blocks instead of iron.

whats a small block way?
bbc ?
others?
hope you can help gary..
grams are the enemy and kilo's the killer

Captain Chaos · 25-04-2009, 01:55 AM

http://www.gm.com/experience/technol...ne_engines.jsp

cosworth mirage · 25-04-2009, 02:46 AM

They still way a ton
shame there not using the newer alloy block 32 valve motors

motorvator · 25-04-2009, 08:32 AM

Your problem with any form of ally block / heads is not being able to use direct cooling and hence adding the weight saving back with heat exchangers etc.

cosworth mirage · 30-04-2009, 10:08 PM

after my search for a light weight motor i found a ford 5ltr 'cammer' t50 crate engine it weighs 197 kilos complete, its all alloy quad cam with magnesuim manifolds and fuel injection,dry sumped and dyno,d at 480bhp .Found on ebay for 560 quid
need crank some rods and pistons plus one liner found a company called highland racing they do a long stroke crank with short rods,new forged pistons brings it upto 5.4ltr for $2000.

cfun · 01-05-2009, 11:03 AM

If only money were no object for engine and development here would be a prime candidate at the same weight as a Merc 200hp outboard around 200KG but packing well over 600+hp and that's without any supercharger/turbo

KMS Racing engines ... actually 2 of these lovely fella's would be just perfic in team Swipes 32' phantom

cosworth mirage · 02-05-2009, 09:33 PM

this is the same motor i got but its boxes of bits.It looks like its lost oil pressure and damaged crank and rods possably pump failure its got a pace dry sump system from uk?.
5.0-liter, four-valve "Cammer" crate engine producing 420 horsepower.
The foundation of FRPP’s hot new 5.0-liter "Cammer" crate engine is rooted in the Ford SVT Mustang Cobra 4.6-liter four-valve engine family. However, the crate motor's flanged cylinder liners help provide 94mm (instead of 90.2mm) cylinder bores, creating a full 5.0-liters of piston displacement. And while the motor employs the 2003-04 SVT Mustang Cobra "Terminator" forged crankshaft with six-bolt mains and Manley "H-Beam" connecting rods for superior strength, the block itself is specially reinforced in the crankcase web areas for high torque loads.
Other key differences include forged pistons, an 11.0:1 compression ratio, ported heads, higher-lift cams and beehive-shaped valve springs. The crate engine also features higher-flow fuel injectors and a magnesium variable-geometry intake manifold, similar to the FR500 intake manifold currently offered in the 2004 FRPP catalog.
Ford Racing's new 5.0-liter "Cammer" crate engine comes with a stock SVT Mustang Cobra oil pan and exhaust manifolds, so an exhaust system – employing Ford Racing prototype metal-substrate catalysts and a set of Ford Racing dual-mode mufflers – was custom-fabricated to put the engine heat to the street.

larby · 02-05-2009, 11:12 PM

How are you going to go about marinising it then? What are you going to do for cooling with it being an alloy engine? Surely the heat exchanger required will negate any weight saved in the first place?

James

cosworth mirage · 05-05-2009, 01:27 PM

checking out heat exchangers now but cant see it weighing more than 25 kilo's, exh manifolds take a lot of time and effort for twin wall stainless headers but it can be done or pos modify some that are close to design needed with some new flanges.

andyxs · 05-05-2009, 03:38 PM

it looks like an amazing project, should go like a rocket when your done. look forward to it!

cosworth mirage · 05-05-2009, 08:55 PM

it should be more straight forward than marinising the cossie turbo that i put in a few years ago (hopefully) but this sort of thing always bite's you in the arse when you think you've get it sorted.But then i don't think standard stuffs without its problems including the large dolops of cash needed to buy it in the start. I quite enjoy the challenge of seing how fast i can get my scrap to go (and for how long).

larby · 05-05-2009, 09:14 PM

I love it because it's different! I'm forever trying to 'improve' on things... It always ends up costing way more and usually isn't any better.... but one day, I'll manage it. Then, Kerching!!

Keep up the good work and keep us posted!

James

Andy B · 05-05-2009, 10:39 PM

Quote:

Originally Posted by cosworth mirage

checking out heat exchangers now but cant see it weighing more than 25 kilo's,

dont forget to add in the weight of the water contained within said heat exchanger! 1Ltr of salt water is just over 1kg

cosworth mirage · 08-05-2009, 10:52 AM

I might use the heat exchangers i,ve got in the boat already they keep the cossie cool but its not got as much power as the v8 but it does produce a lot of heat for the power you get( downside of turbo,s) maybe build a good size oil cooler into the dry sump tank with a scoop feed and oil stat.
found a good price on forged 5.4 ltr stroke crank $739.00
jeggs do headers for this engine in stainless would have to weld an envelope around manifold for cooling i think this is probably best option for power and cost $415 for pair.
trailer is couple of weeks from completion so going to try boat with its new drive/prop combo + extra 30-40 bhp from engine so looking forward to this i don,t think i can get much more from this engine without reducing engine life
hoppfully i will get some good speed this year then,ripe it all out and start again.(i must be mad)my wife thinks deffinatly insane