vtown

Sick boat. Great engines for a 6 speed transmission. I think 1st thru 6th gear are within 20%. now the lower TQ/HP at lower rpm compared to BBC is not an issue. for everyone else with 1 spd that ls7 has less accelleration that a similar peak hp 500+ ci BBC. VVT in the ls narrows the gap

vtown

The LPG engine makes alot of sense at that power level...If your boat and prop allowed you to cruise out of boost then it would be better on fuel. otherwise you are paying the same as a 502 whippled BBC 800hp and getting 675hp, would still need an XR or better. i guess it depends on your boat...Im always comparing single high hp to twin ls's. For my boating interests I think N/A 500+ hp ls with stock bravo 1x is unbeatable for total cost (including drive), power, reliability. twins will allow semi-serfacing for speed without crabbing the drive (single) and having to use expensive custom 5 blades. Higher rpm pf the ls's give a larger power band so a top speed prop will still get on plane easy.

JJONES

normally aspirated .no turbos,no blowers, v bottom, 40'. I recon its real good

Fenderjack

iTrader: (2)

The LS would be a perfect set up in a lighter boat, but that has already been stated. Wasn't or isn't there a guy on here that has 2 5.3's in his 28-30 cat that is running north of 100? These things are with out a doubt as strong as some aftermarket SBC_BBC parts. 2 lq4's or 9's could be done fairly cheap. Have the bottom ends balanced, put them back together, add new cams and push rods. Always gona be guys on both side of the fence as far as what is better, but it will surly be based on the set up and boat it is going in. I have a 6.0 block in the garage now with over 120k on it, the cross hatching on the walls still looks new. I see no reason why a properly tuned LS on a constant 10 lbs wouldn't last in a marine set up.. Also some 6.2's in the trucks are iron blocks.


John jr

GTOKILLER

iTrader: (1)

Kinda what I though, that thing sounds good though!! I know BBC sound great but that will grab your attention!! Hope mine sounds good twisting about 7k across the water!! (not LS's though)

Cole2534

iTrader: (1)

Hmm, now I'm interested. Make 550hp, NA, lose 500#, and it wont grenade my B1?

Get the F$&k out, that's make the 24' fly.

vtown

A 496 HO has about 500ft/lbs TQ at 3600 rpm and peak hp 420 @ 5000 RPM. 416ci LS3 with VVT is about the same peak TQ and HP numbers at similar RPM with 1000 more RPM for higher peak HP at around 550. will get on plane the same with the same prop, wont stress the drive more since the boat is freed up after 5000 rpm has higher top speed with more RPM and is MUCH more fuel efficient with smaller CID possible with higher VE. Seems Like a really good combo to me. The weight savings may make it a better performer than a 525 efi depending on boat

IROCDave

If you are really interested in a LSx conversion, go to this site.

http://ls1tech.com/forums/conversion...otor-boat.html

These guys are hardcore LSx and have apperently converted many Lsx engines to marine use.

cheech

Same as your avatar? So not LS? What kinda specs on them?

Hardin Marine

For those of you that are interested in making the LS Marine engine conversions we have a whole slough of new products that will be released next month from block mounted sea pumps to Closed cooling kits, to LS engine mounts that bolt right in place of Mercury HI Perf mounts. We've had a number of customers make the swaps with huge success.