I am currently building (4) LS engines for a twin 28 Eliminator Daytona Tall Deck and 32 Sunsation Dominator. Figured I would let the cat out of the bag for future reference as a go to for people that attempt this. These engines will have prak torque at about 5000 and peak power at 6200. Roughly 625hp 600tq and make a 525efi look like a fool the entire powerband. We will be rev limiting them at 6200rpm. Remember these are not bbc and can easily sustain that rpm for hours on end. Fuel consumption per engine will be roughly 38-40 gph wot. Way better than the blown bbc we are replacing which where burning 110gph each wot. My fuel savings alone the first year alone will pay fir the builds. Onto weight savings. 1000 lbs per set per boat. I have a 67 GTO Aluminum 5.3 LS turbo making big power and know the ins and out of these engines well. Make sure you read the notes after the specs if you attemp this. Dyno sheets, progress reports, and pics to come soon. Engines being assembled within a week. Here are the 28 Daytona engines. Enjoy

Specs: 408ci ly6 blocks 4” stroke 6.125 rods 4.030 bore 10.8cr mains: .0028 rods: .0030
6.0 iron blocks: 4.030 bore, decked .006, cnc honed to 500 finish, arp main studs
Rotating Assemblies: K1 4.00” forged cranks, k1 h beam rods, wiseco 8cc flat tops, wiseco rings
Heads: Ls3 cylinder heads w/ dual .660 springs Cam Motion/ milled .006 68cc
Camshafts: Custom 222/232 114+2 .621/.605 Cam Motion Lobes
Induction: Holley Ls3 dual plane 300-129/ Quick fuel 950 Q Series
Rockers: Ls3 with trunnion upgrades
Ignition: Msd 6014
Oiling: Champ 10.5 qt pain part# ls1060, Melling 10296 HV oil pumps/ billets barbell From Sac city
Exhaust: Marine Power Manifolds with gil tall hp500 tails
Cooling: Hardin remote thermostat for raw water cooling/ crank driven water pump/ 3x18 oil coolers/ 210 oil thermostat/ 160 coolant thermostat
Fuel pump: Holley Hp125
Push rods: Comp 3/8 restricted oiling (See notes for reasoning)
Lifters: Ls7

Notes:
LS based engines have a tendency to pump oil to the heads and have trouble draining it back. Mods are required especially when using a high volume pump to ensure oil starvation is not present. Restricted pushrods with .050 orfice hole allow plenty of oiling to top end while not over doing it. The lifter trays must be drilled with 1/2” holes just below lifter center which hrlps with drain back. An alternative is to use link bar lifters which eliminates trays and further aids drainback but is not a neccessity. Blueprinting the casting flashes on the block and heads is a good idea as well. The billet barbell has much tighter tolerance and eliminates bleed out at rear of block. A billet plug is also installed eliminating the oil bypass in the block. 10-12an lines should be utilized for remote oiling. Other things to not is the stock ls rockers (very good units) must be upgraded with trannion upgrades. This is critical. I lost a engine not doing this in my 67 Gto 5.3ls turbo car. I cannot emphasize this enough. Lift limit of stock lifters is .630. This is perfect as LS3 heads are rather lazy on air velocity and I tend to limit lift to .620 range.

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I will keep this updated as progress happens.

you might be surprised at what unported l92 will do. I went minimum on the cam to broaden the entire curve rather than loose a bunch of power and have to rev to 65-6700 for peak. Also I am looking for zero reversion, which it has -1 overlap @ .050 evc 0 .006 overlap 54. All safe on my end with monster torque ad good power. I did consider about 10 degrees bigger but it would be maybe 30hp more above 5k for a major loss of torque below 4500. In order to stay in the bigger degree it forces wide lsa which we both know hurt power. Without wider lsa reversion is imminent. Ive done a 6.2 with a l92 heads stock with 222/230 114+4 at same lift and did 480rwhp through a 4l80e which is about a 23% loss to drivetrain. Cnc heads generally only help on ls3 heads above 5400 which I cant justify cost for 20hp. Dyno will tell soon enough. Lol. Good luck on your build post it up on here

1.5hp per ci. Piece of cake on LS.

Dyno will be posted in about 3 weeks. More than happy to share results. I posted this in the first place to be informative, not to start a pissing match.

You aren’t making 625hp through that exhaust manifold. Dyno in marine trim and let us know. Needs real headers and then more cam.

https://cimg9.ibsrv.net/gimg/www.off...78acfd2cc.jpegThis manifold looks better but it’s got a cat in it I think.

I will concur with that. With dyno headers it will be right there. The marine power manifold is the exact same manifold as imco power flow from imco. Exact. If you look at a cutout of it you will see it is like a shorty header. So not too bad of restriction but will come up 25-30 short due to that. I do plan on running it both ways on dyno as I have future plans to add lightning headers and would like to see the diffeence in headers snd manifolds. Should be fun either way. Well over 100 mph either way. If I lose 3mph from exhaust so be it

I did look at that exhaust as well but it is pricey. And my daytona has to have custom tails due to lower outlet than stock bravo. About 3” lower

Watch this. Look closely at the chart. Same exact specs on cam but using less lift and xfi lobes. It DOES have gm performance cnc heads which are good for 20 in the range hes in. My lobes will make more power than the xfi lobes.

525s make 560 in dyno trim with the different correction factor than merc uses. I’d be interested to see if your engines are any faster. The weight reduction will help.

I have a LS build also.

6.2 aluminum blocks
821 heads (ported)
Manley pro flow valves
Manley severe duty exhaust valves
Howard’s 98113 K1 spring kits
Howard’s ASA cams with 3 bolt
flat top pistons
full roller comp 1.8 rockers
mellings 10355 oil pumps
15 lb flywheels
light weight starters
Teague custom marine crossovers
dual 150 thermostats
aluminum sheet metal intakes
102 mm throttle bodies
thin head gaskets

keep us updated on this

I heard about your 67 gto death grip ride. Bad azz from what I heard. What ratio rockers you running. I may have missed in OP.

Dennis r built and just sold a while back some stroked ls3 with ls3 cnc ported heads and made like 650 hp at 6,500. Ck out his build sheet. Ran them in a 32 sunsation 88 mph.

I guess Tom told you about her. Puckered his butthole up a lil with some 100mph burnouts. Lol. Im running a 1.7 ratio. Im letting my cam lobe choice do the work. The second two ls engine being built are actually for Tom in the Sunny I gave him. Much milder build than mine though. I spoke to dennis when I was in michigan about his builds and have his cam specs. Very nice numbers on his part and on hell of a nice guy. Im looking to drag power down into a more usuable range for where I plan on running. I am specing a single pattern as we speak. Contemplating 232/232 114+2 and 237/237 114.5+4.5. Events look good and both keep me in range of rpm. Lower torque trade off is contemplation.

have not not heard that term since 1987

Your killing me Smalls. Lol. Ordered 237/237 114.5+3.5 .621/.612. Very broad power but will loose my past peak power without exhaust split which is not a concern. I build my cam totally off of events. Not @.050 or adv numbers. Concern with this cam is planing as the daytona is very tricky to push over and low end will indeed suffer. Counting on the dual plane to do its job there. Will have great power from 3500-6200 though. We will still be utilizing the original cam on the Dominator which is a 6.0 ls3 heads.

I love projects like this and looking forward to the results.

Keep up the good work and keep us posted regardless. Hey worse case scenario you don't achieve your goals but you certainly don't reach them by couch sitting just thinking about it. Your going after it. Would be great if you could try a couple different cams on the dyno and share your results. That's kind of the backbone of this site and much appreciated by most. Also do a search on even split cams here. There was a thread on it a fews ago if I recall. The last custom grinds I bought had only a 4 deg split and made great power once I got the valvetrain stable. The last even split cam I ran was in a 383. Never forget comp labeled it as king of the drive in cam and that it was. 292 magnum cam.

I ran that with GM worked over camel back heads (closed chamber) with a non superior exhaust port. Was a crap shoot at the time being only 18 but made excellent power.

Hi John. Testing with ls3 heads has shown on a stock displacement 6.0-6.2 that a 0-4 split, reverse and forward split believe it or not, works excellent. On a 4” stroke the same applies. The difference I have found is in the overlap #. Stock displacement is happy around 4 where the 4” stroke likes 8 degrees. The cam I specced nails these nimbers. The lack of split will loose my carrying of the power past peak but I am not shifting gears where We need to rev past peak to drop back into the powerband on the shift. I will hit the peak and set the rev limiter. Alot of guys think these heads need a big split due to the .500-.600 ie numbersbut never consider the 2-3-4 ie ratio which is excellent. I will definitley condider cutting a few more cams for testing purposes to show gains and losses.

I respectfully disagree. The events justify the cam. Mainly ivc and evo. The ivc determines peak. The evo determines where the powerband is located. The split determines how well it holds power past peak but also softens low and mid power creates unneeded overlap on in my case a rather lazy intake port. Low initial velocity creates intake reversion due to overlap. So one this particular head I do want less split which is clearly justified. Ill post a pic of the cam card when they arrive so you know my upcoming dyno sheets are not bs. Ill also post the baro. Humidity. Temp and correction factor being used. Wherever it ends up hp wise is where it is. But the numbers will be real and a good aid for future builds. Again the pount of this thread.

Very nice. Will be a great runner. You got a damn good deal on those

You can use the LSA supercharger on the ls3/l92 heads from ctsv, zl1 camaro, or z06. Easy to be had and already intercooled for under 2500. Two other options are bds has a carb blower and hardin marin has a turbo header which Would make retarded power but is an expensive option at 4000 for just the header. Another thing to remember is gearing. The LS can sustain much higher rpm without drawbacks. Mine will rev to 6200 before I stop it. That alow gear ratio torque to help transfer to the prop by using higher ratio but still being able to get great speed fo you rpms. On my daytona I am going to be utilizing 1.5 gear ratio compared to normal 1.36 or 1.26.

https://cimg7.ibsrv.net/gimg/www.off...853094f025.png
Wildman - I have no baseline as the Hull is new to me. I can compare the dyno sheets from the LS3 to a 509 I had (HP500 w/ AFR305s and a Bob Madeira can). You can compare the torque curves.

Nice

What headers are they? Looks great.

Thise are cmi

When I had an air to water intercooler on my gto similar to lsa supercharger I ran a big pump to a secondary radiator as an isolated system. In this case im sure you could run a small heat exchanger and pump or even secondary standard oil cooler but instead of oil run coolant through the AN lines and raw water where it would normally run in. That would also be sufficient. The A2W radiator we ran was actually rather small and kept the IAT in line very well. And this is in track/riad conditions with long extended pulls unlike drag cars. I ran 12an lines and a 2x10x28 core on that.

The LS7 if you want my opinion is good when they run. Expensive. Do sime research online and you will find quiet a few failures fir such a small produced engine.

I get that the 1.5 is stock but my point was that my daytona had 1.36 and by switching to 1.5 it allows me to amplify prop torque as well as spin in the rpm range I am intending while still maintaining the est speed we will be seeing (107-115)

From the dyno sheets, with the exception of 6300+ RPM, the largest gap is at 4600 RPM, about 46 ft lbs. That’s only an 8% gap.

By the numbers, it looks negligible to me. Does anyone have any real world experience of what that level of difference actually feels like? Can you even notice 8% difference? ...maybe the amazing sound will distract all other senses ��

And wouldn’t the weight difference offset it?

(...and between 3650-4100 RPM, the LS has more torque than the 509)