Running a 450HP LS3 on LPG

Post Reply
Message
Author
skiergeorge
New member
Posts: 7
Joined: Tue Dec 06, 2011 3:18 pm

Running a 450HP LS3 on LPG

#1 Post by skiergeorge » Mon Jan 13, 2014 8:15 pm

Looking for advice. Been running OMVL Dream twin regs and think they call them superlight injectors. Upgrading our boats from 350 to 450 HP with the LS3 and doubt this kit will cope. Already running quite how map around the 200's . I am fitting the kit in boats so need quality kit with good response times as our ECMS put the power down fast. Tempted by Prins but cost seems very high. Have tried BRC but had issues on the overrun.

classicswede
Installer
Posts: 2583
Joined: Fri Oct 21, 2005 8:56 pm
Location: North Wales
Contact:

Re: Running a 450HP LS3 on LPG

#2 Post by classicswede » Mon Jan 13, 2014 10:02 pm

I have done a lot of ski boats over the years and the AEB electronics do work well. Getting the water feed sorted is a big key part.

If you have the old OMVL HP regs then they are not great in all honesty. 5 years ago yes they were one of the best but there are now better reducers out there. The OMVL injectors are ok but at those power levels will be getting near the limit of flow.

Are you changing the ECU from group injection to sequential to go with the engine change?
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

skiergeorge
New member
Posts: 7
Joined: Tue Dec 06, 2011 3:18 pm

Re: Running a 450HP LS3 on LPG

#3 Post by skiergeorge » Thu Jan 16, 2014 3:51 pm

Thanks for that information. I ended up with OMVL Regs because we could keep the gas temp up with EMME Gas. OMLV injectors I am sure won't cope as we are nearly flat out on our 350 Vortecs. Latest Idea is a King ECM with Hanna injectors. Heard they are like Kehin.

skiergeorge
New member
Posts: 7
Joined: Tue Dec 06, 2011 3:18 pm

Re: Running a 450HP LS3 on LPG

#4 Post by skiergeorge » Thu Jan 16, 2014 3:53 pm

By the way we use the sequential injection as all out boats are individually injected now. No Group Injecting since 2005. We are also using pre and post lambda sensors. Often having an issue with trimming at idle where one bank goes lean and other rich. Dip Tubes help that issue.

classicswede
Installer
Posts: 2583
Joined: Fri Oct 21, 2005 8:56 pm
Location: North Wales
Contact:

Re: Running a 450HP LS3 on LPG

#5 Post by classicswede » Thu Jan 16, 2014 7:36 pm

Most of the boat engine even with 8 injectors operate a full group injection stratergy.

The hana injectors are good and will flow well
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

skiergeorge
New member
Posts: 7
Joined: Tue Dec 06, 2011 3:18 pm

Re: Running a 450HP LS3 on LPG

#6 Post by skiergeorge » Fri Jan 17, 2014 8:26 pm

Thanks again, I have been thinking maybe a King ECU with Hanah injectors, just not found out if King have the latest AEB software available. Other option is BRC.

rossko
Installer
Posts: 8094
Joined: Wed May 23, 2007 6:51 pm
Location: Wiltshire

Re: Running a 450HP LS3 on LPG

#7 Post by rossko » Fri Jan 17, 2014 8:38 pm

skiergeorge wrote: just not found out if King have the latest AEB software available.
Why, what do you think it does that, say, last year's doesn't?
www.blazegas.com

classicswede
Installer
Posts: 2583
Joined: Fri Oct 21, 2005 8:56 pm
Location: North Wales
Contact:

Re: Running a 450HP LS3 on LPG

#8 Post by classicswede » Fri Jan 17, 2014 10:09 pm

Temp corrections? I've not needed them on any of the boats I have converted.
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

LPGC
Installer
Posts: 3205
Joined: Wed Sep 29, 2010 6:01 pm
Location: Yorkshire
Contact:

Re: Running a 450HP LS3 on LPG

#9 Post by LPGC » Sat Jan 18, 2014 12:19 am

The vast majority of sequential ECU's have built in gas temp correction, even if it is none adjustable, there are only a few sequential ECUs that don't.

All AEB ECUs including King have both gas and water temp correction but with some software / firmware / lack of dongle combinations you cannot adjust them. The latest King 6.1.03 software does allow access to adjust both temp corrections, but as has been said, you shouldn't really need to do that.

OMVL SL's will flow enough gas for the 57bhp per cylinder if you remove the brass nozzles from the outlets and use an appropriate feed pressure. By appropriate, 1.5 bar should be enough and a wide range of reducers will stretch to this pressure. They would give good results but there are better injectors for higher power levels.

You do have high map figures, but remove the brass nozzles from the injector outlet and recalibrate the system then tell us what the map numbers are! I bet those 200s will come down to around 140s. What pressure are you running at?

Does the boat have cats then? You said it has post cat probes? What kind of bank trim problems are you having? What are the bank trims like on petrol?

Simon
Lpgc
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240

classicswede
Installer
Posts: 2583
Joined: Fri Oct 21, 2005 8:56 pm
Location: North Wales
Contact:

Re: Running a 450HP LS3 on LPG

#10 Post by classicswede » Sat Jan 18, 2014 12:23 pm

The vapourisers should be running around 1.8 bar, one is enough for the power but getting the heat with a boat is the problems and two vaps is the best way. You can take them upto 2.5 bar, omvl made a spacer for the high pressure spring to do this.

What temp readings are you getting on the vapourisers under sustained full load?
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

skiergeorge
New member
Posts: 7
Joined: Tue Dec 06, 2011 3:18 pm

Re: Running a 450HP LS3 on LPG

#11 Post by skiergeorge » Tue Jan 21, 2014 6:59 pm

Thanks for all the good information. Did not realise you could space to 2,5 bar, back to the good old impco days. Can the OMVL injectors take 2.5 Bar ? I also suffer pressure drop on the OMVL regs down to a bar at full throttle. I already take the brass nozzles out for anything above 350HP. When I take the nozzles out I do suffer on idle trimming I guess due to the lower nozzle pressure. I never really pay too much attention to post cat sensors only the pre cat. Sounds like I may be able to stick with OMVL although Hanah injectors do tempt me. By the way I really do need 2 regs to keep the gas temp up, circulation is terrible at low revs. I am injecting alot of gas as well. One issue I do have is by the time I include dip tubes and the supply piep I am 15 inches from injector nozzle. The boat ecm we use does have adaptive learning by the way as well.

classicswede
Installer
Posts: 2583
Joined: Fri Oct 21, 2005 8:56 pm
Location: North Wales
Contact:

Re: Running a 450HP LS3 on LPG

#12 Post by classicswede » Tue Jan 21, 2014 8:34 pm

They will work at over 2.5 bar no problems.

What is you petrol injection times on tickover?
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

skiergeorge
New member
Posts: 7
Joined: Tue Dec 06, 2011 3:18 pm

Re: Running a 450HP LS3 on LPG

#13 Post by skiergeorge » Fri Jan 24, 2014 11:53 am

Hello .

Injector times for petrol are around 3 which gets adjusted to 5.5 to 6 ms when on LPG.

classicswede
Installer
Posts: 2583
Joined: Fri Oct 21, 2005 8:56 pm
Location: North Wales
Contact:

Re: Running a 450HP LS3 on LPG

#14 Post by classicswede » Fri Jan 24, 2014 10:16 pm

Is that 3ms on petrol and 6ms LPG? Or does the petrol time climb to 6ms?

Are you using the full group setting or sequential?
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

skiergeorge
New member
Posts: 7
Joined: Tue Dec 06, 2011 3:18 pm

Re: Running a 450HP LS3 on LPG

#15 Post by skiergeorge » Sun Jan 26, 2014 9:51 pm

The petrol injection at idle is around 3 ms and this converts to 5 or 6 on LPG. Alwaysuse sequential not full group. Petrol map is pretty solid with learning never varying by more than 1 or 2 %. On lpg I can sometimes end up 16 to 20 % adjusted off petrol map. I have factory level connection to petrol ecu.

classicswede
Installer
Posts: 2583
Joined: Fri Oct 21, 2005 8:56 pm
Location: North Wales
Contact:

Re: Running a 450HP LS3 on LPG

#16 Post by classicswede » Sun Jan 26, 2014 10:04 pm

I would say you are not getting enough flow there. With a petrol time of 3ms I would expect as LPG time of around 3.5 to 4.5 ms on LPG if you gas pressure and injectors are sized correctly.
http://www.classicswede.com/
http://www.classicswede.co.uk/LPG/cat17 ... 10800.aspx

LPG installer Anglesey North Wales

DIY LPG Kits

07824887160

Post Reply