Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   LS Build: In Progress (https://www.offshoreonly.com/forums/general-q/358652-ls-build-progress.html)

mggdoors 03-03-2021 07:29 PM


Originally Posted by sutphen 30 (Post 4780025)
what computer did you use?

Holley Terminator on these ones. Also run Dominator on another build. Both are excellent

Bajaorlando 04-11-2021 08:00 AM

Any updates on how it ran in your boat

mggdoors 04-11-2021 01:08 PM

Not yet. Should be on water in 30 days or so. Just finished cut and buff below rub rail on paint job. Another week-week and half for top then back together she goes. Literally polished/powdercoated/reupolstered etc everything in boat. Full resto.
https://cimg9.ibsrv.net/gimg/www.off...90ee01b2e.jpeg

Hot Rod 29 07-01-2021 04:16 PM


Originally Posted by mggdoors (Post 4745293)
The lt4 is a different beast than mine. It is direct injected with a higher compression and heads that flow 50cfm more out of the box. The lt4 supercharger will not work on ls applications due to wrong port match and no injector bosses. This dyno run is at 148kpa/7.1psi boost. Had belt slip which you can see in posted dyno log. It is cable driven throttle. We are using the factory intercooler modified with gusseting to prevent collapsing it under sustained load. Cooling is raw water ran through an iron ly6 block no thermostat. If you go aluminum block you will have to go closed cooling because block temp must rise to I would say 160 to allow bearing clearance to grow otherwise you will dstroy engine. We should see upwards of 9psi when belt slip is corrected which will easily push us over 800. Yes it is 1.9 tvs. Keep in mind that I am barely using the potential of this supercharger. With a lower pulley change we could be upwards of 16-18psi. But would require e85

are you running raw water through the inter cooler?

neuer_Typ 11-04-2021 08:39 AM

:nicethread:

I will build a stock LT1 Gen.V in my 29ft Velocity VR-1.
Only 460 HP but the VR-1 is a light weight hull.

I hope it´s enough power for cruisin. :whistle:
What do you think?

mggdoors 11-04-2021 08:52 AM


Originally Posted by neuer_Typ (Post 4811350)
:nicethread:

I will build a stock LT1 Gen.V in my 29ft Velocity VR-1.
Only 460 HP but the VR-1 is a light weight hull.

I hope it´s enough power for cruisin. :whistle:
What do you think?

I think you better run closed cooling or you will murder the mains when the aluminum block fails to heat up and expand the bearing clearances. Otherwise its a great engine. I personally would do an l8t. You get an iron block which is only a few more pounds but you get a long stroker 6.6L. A cam swap would be easy 550hp

Wildman_grafix 11-04-2021 09:34 AM

What ever happened with this project?

mggdoors 11-04-2021 09:51 AM


Originally Posted by Wildman_grafix (Post 4811362)
What ever happened with this project?

life. Its all finished up. Just havent had time to take it out. We went straight from that to my GTO repaint/ tremec tkx swap/ etc to my yard on my house. In the last month I built 1400ft of pipe fence, laid 4000sqft of grass, and about 200 tons of rock/dg. Finishing that up currently. I will update when we get it out. Maybe after holidays.

neuer_Typ 11-04-2021 10:42 AM


Originally Posted by mggdoors (Post 4811352)
I think you better run closed cooling or you will murder the mains when the aluminum block fails to heat up and expand the bearing clearances. Otherwise its a great engine. I personally would do an l8t. You get an iron block which is only a few more pounds but you get a long stroker 6.6L. A cam swap would be easy 550hp

Yes, i will run a closed cooling system!

I´m in germany....no chance to get a 6.6L.
But....it would be a nice project....if i need 800hp+ :riding:

Derek Iwasiuk 01-28-2022 10:48 AM

if you were to build this more for a midrange torque and go NA and no stroker kit, would 317 or even 243 heads work well instead of the LS3 which I believe like higher revs? trying to spec out my 6.0 NA build for small lake boat but want good get up for ski.

mtnrider 06-30-2022 12:41 PM

any progress with this build

articfriends 07-01-2022 06:43 AM


Originally Posted by mggdoors (Post 4767590)
Do yourself a favor and pull the intercoolers and gusset them. Also run the zl1 lid if possible. Good for 20 or so hp and intercooler is more efficient. Port them as well. I did mine. Pay close attention to the area right above the gasket area that mates to head. Youll notice square edges. Round those out and open them up. Injectors I would decap the zl1 injectors and have them cleaned and flow matched. Good for 105lb/hr. And cheap. Last but not least a nice little trick if you dyno them and your ecu has capability is to fire injectors the second the intake valve opens or 0-5 degrees before and stop them at or before the valve closes. Easy BIG hp gain and does let fuel pool behind calve/cleaner afr etc. I actually showed my dyno guy this and he couldnt believe the gains. Over 40hp in my case. If you have overlap and can get enough fuel in within the valve event I suggest injecting after the overlap event. But only if you can get adequate fuel in by the time it closes.

Where did you see the '40 hp" gain from timing a port injected injector rpm wise? Im skeptical as I own a dyno and high end injector machine and have never found a single hp gain form sequential or timed injectors in a port vs batch fire OR a difference in AFRS whatsoever off of idle. Heres the reason WHY I disagree with the 40 hp gain: at say 6000 rpm, the intake valve is opening and closing 3000 times a minute. The injector is also firing 3000 times a minute. at a typical top end MS of say 13 MS, the injectors firing for .013 seconds (keeping deadband out of discussion which is minor) , extrapolating the data out to 3000 times minute, .013 x 3000+ 39, thats 39 seconds, so of in a minute of valve opening and closing 3000 times, the injector has sprayed fuel pretty much steady for 39 of those 60 seconds, so about 70% of the whole time. this is assuming the injector is NOT set to double fire and is only firing every 4 stroke revolution. When you see a injector on machine at anything over than equivalent to 2500 rpms, its a steady spray so i disagree 100 % with the 40 hp gain, you may have made other tuning changes and saw a gain but after a certain rpm your injector is spraying a giant stream/fog of fuel, Smitty
Now a direct injected engine, especially a diesel, yeah, I can see by advancing injector timing there can be a power optimization

PODUNK RACING 03-18-2023 04:06 PM

Good information!

mtnrider 03-19-2023 01:52 PM

Did you ever get the boat back in the water

hogie roll 01-17-2026 10:54 AM

Just reread this one. Wanted to say thanks for all of the posting and data. I know we gave you a hard time.

I think if going NA with LS engines for a boat a guy would want to utilize all of the 9.3” deck height and get really aggressive with the stroke, like a 4.125” if possible. Better yet a sleeved aluminum block or aftermarket block with a big bore too. But then the budget comparisons to big blocks have really gone out the window.

Utilizing stock take off blowers like you did is really the smartest move.

mggdoors 01-17-2026 03:30 PM


Originally Posted by hogie roll (Post 4941586)
Just reread this one. Wanted to say thanks for all of the posting and data. I know we gave you a hard time.

I think if going NA with LS engines for a boat a guy would want to utilize all of the 9.3” deck height and get really aggressive with the stroke, like a 4.125” if possible. Better yet a sleeved aluminum block or aftermarket block with a big bore too. But then the budget comparisons to big blocks have really gone out the window.

Utilizing stock take off blowers like you did is really the smartest move.

no worries, my engines are still up and running great. We have Sens converted them in the last two years over to LSA ported Blowers and blah blah blah and we have them up to just over 1000 hp. Each different cam specs, of course. I can say this my 28 tall deck hauls ass and I can hold 6500 RPM’s as long as I want. We generally run them 5 1/2 pounds of boost. They make 767 hp each and about the same torque. Notice on the diner run we stopped at at 6400 RPMs even though we are still gaining over 20 hp per 100 RPMs that was our final tune for how we run it in the boat 90% of the time to try to keep the drives alive.
https://cimg3.ibsrv.net/gimg/www.off...28acef908.jpeg

hogie roll 01-17-2026 05:54 PM


Originally Posted by mggdoors (Post 4941602)
no worries, my engines are still up and running great. We have Sens converted them in the last two years over to LSA ported Blowers and blah blah blah and we have them up to just over 1000 hp. Each different cam specs, of course. I can say this my 28 tall deck hauls ass and I can hold 6500 RPM’s as long as I want. We generally run them 5 1/2 pounds of boost. They make 767 hp each and about the same torque. Notice on the diner run we stopped at at 6400 RPMs even though we are still gaining over 20 hp per 100 RPMs that was our final tune for how we run it in the boat 90% of the time to try to keep the drives alive.
https://cimg3.ibsrv.net/gimg/www.off...28acef908.jpeg

You dynod to over 1000hp with those blowers?

mggdoors 01-17-2026 06:30 PM

Correct

Originally Posted by hogie roll (Post 4941603)
You dynod to over 1000hp with those blowers?



All times are GMT -5. The time now is 03:40 AM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.