Just curious if it is possible to tune a TJ VR-X to run on 98 but also be able to switch to LPG?

Cheers.

Theres a few cars on here/were on here that have had this done, inc mine. 60K and 3 years no detonation or fuel related problems.

They are on SVI LPG systems, but that wont matter....

Ah ok cool as!

Thanks

Your question should be other way around. Is it possible to tune for LPG and run the car on 98. Answer is no. If you tune for LPG and run the car on 98 petrol you will be knocking. At the moment in running 98 tune, when i switch to LPG it runs pretty much the same, i.e no knocks, except im running LPG much leaner then petrol (since LPG has no cooling effect of petrol, it is pointless reducing your AFRs like you do with petrol). In my supercharged setup im running AFR of 14 on gas, no knocks whatsoever.

Anyhow to answer your question, yes you definitely can run LPG on 98 tune no worries.

I have one of the VRX's running on 98 octane and LPG.
No knocking and it runs smooth as with plenty of power (ok, I haven't put it on a dyno to compare the power difference, but there isn't much between them).
I have a great mechaninc in my area that is an LPG specialist and he looks after all may dual fuel cars very well (and I still get 580k's from 64 litres of LPG on the highway)
The trick is, get the car running spot on for 98, then get the LPG setup for it. My other cars run on 91 and LPG and also have no issues, it's all in the setup.

I have one of the VRX's running on 98 octane and LPG.
(ok, I haven't put it on a dyno to compare the power difference, but there isn't much between them).


I have, its about 2 kw difference, most of difference is in the mid range, blue line is LPG. If you tune your spark for LPG instead of petrol you will actually produce more power than petrol!

http://i1012.photobucket.com/albums/af244/e363ma78/5SpeedManual.jpg