LPG Discussion Forum

So, on the subject of GEMS being better than my batch fired Canems duel fuel stand alone ECU I think it's important to accept while fully sequential injection may indeed give a slightly more refined idle and lower emissions at idle it really isn't the holy grail many will have you believe. There's ...

Merek makes some good points, people should understand this project was a personal deep dive into engine management first principles, it's as far off slapping an LPG piggyback ECU on my ancient original 14CUX ECU as you could imagine, and unsurprisingly the results are in a different galaxy to such ...

Thanks for your comments chaps, firstly a couple of points on gas pressure & temp:

1. I implemented both and still have these features

2. Extensive on road and hub dyno evaluation proves them to be largely unnecessary

Horsepower and torque outputs along with carefully monitored AFRs at all ...

Four years and tens of thousands of miles have passed since I started this post, and I'm pleased to say my LPG TVR Chimaera is still delivering exceptional performance, drivability, reliability and fuel economy.

Anyone considering converting a performance vehicle that runs carburetors or as in the ...

There are little gains to be made by tweaking petrol ignition maps for LPG .

Massively disagree, all our rolling road time conclusively shows ignition delivers the single biggest influence on cylinder pressure (power) and efficiency, we can incrementally dial in & observe EGT & power changes ...

The reason why, perhaps, I mentioned anything was because you said the system runs open loop much of the time

Nope Simon, definitely never said that, all I said was it only goes closed loop when certain rules are met, this is governed by load, throttle position & coolant temp perimeters, the ...

The statement is: "proven not required for perfect LPG operation"

I say this quite simply because we proved time & time gain we could achieve perfect LPG operation without the need for volume/temp correction.

That's not to say volume change isn't taking place, in fact there is absolutely no doubt ...

TVR Chimaera 4.0 litre V8
LPG System: Canems Duel Fuel engine management system
Tuning: Unique fuel & ignition open loop maps built for each fuel type
Additional strategy: Enters closed loop to follow AFR targets when certain rules are met
Notable exclusions: No LPG fuel temp or pressure sensing ...

Wow I'm really surprised at all the negativity at the end of my project.

Especially seeing as it's been such a success.

When I first came on here people told me to piggyback the 14CUX, really!!

How in God's name can manipulating a petrol injector signal that's completely wrong for LPG in the ...

I'm still not conviced about no gas temp and pressure correction with the ECU setup you have chosen but it looks like it is working well enough.
Wrong, it works actually brilliantly.

But you do seem to have answered your own question so I'm not really sure what you're trying to say here?

I did ...

A big thank you to Keith Woods at Quest Motorsport who made an excellent job of turning my dual fuel TVR Chimaera idea into reality.

http://www.pistonheads.com/gassing/topi ... n%29&mid=0

I have not mentioned Canems ONCE in any of my posts and I haven't endorsed it - I have no experience of it, but I hope it works for you.

kind regards
Marek

I understand Marek, apologies if I made it look like you were endorsing the Canems.

I was referring to the big play you made of your ...

Hi Gilbertd,

Thanks for taking the time to look at my project, I'm pleased you like it.

I raised the LPG position question with Keith "Woody" my installer, at which point I was promptly taken to his own converted Skoda.

This uses Keihin injectors as does my conversion, & their position was very ...

Cheers chaps, you have taught me a lot here.

Shall I take your latest responses as thumbs up for the Canems Dual Fuel ECU?

I must say it's performed fantastically well on petrol so far, and has proved to be a huge step forward from the Lucas 14CUX & distributor which I had always planned to ...

Thanks again marek, you explain things well.

I appreciate the time you are giving me here.

So if the reducer temperature follows, but runs a bit lower than coolant temperature, it should reach a point of being constant as it will in effect be governed by the thermostat & cooling fans.

The only ...

Spot on marek you've made an excellent job of highlighting the benefits as I see them.

On the subject of LPG fuel density corrections, I have raised this a number of times with Keith Woods (Woody) and he is very insistent this will not represent an issue for him whatsoever.

To be honest I only ...

Thanks Rossko, I'm very happy so far.

Like you say the proof of the pudding will be in how the system performs.

I'm confident Keith (Woody) has all the bases covered.

I'm very much enjoying working with Keith, it's tuning into a really fun project.

Keep an eye on the Pistonheads post as that's ...

Well it's happening folks, in fact it's well under way.

Not long now it'll be leaving Woody's workshop running on LPG.

For anyone interested, you can read all about it here:

http://www.pistonheads.com/xforums/topic.asp?h=0&f=8&t=1255616&mid=165876&nmt=LPG+Chimaera+%28Follow+My+Conversion%29

Hi all,

I did promise an update, so here it is.

I've already invested heavily in the project, although LPG is not normally associated with this type of car I see no reason why it shouldn't work very well if I can get the installation and packaging right.

So for those interested, essentially I'm ...

Thank you for your kind comments, please excuse me for being blessed with a quality education.

Joking aside, I expect to update you all on the project in the coming months.

Kind regards, COG.