VRS TFSI LPG conversion

[lloydy123]

Hello Briskoda!!

I have been reading this site for quite a while although i only joined last night as I am seriously considering joining the Skoda family.

I have 2 requirements from a car - Needs to hold a lot of gear and needs to be a stimulating drive. Pretty clear to me that almost the only car that fits the bill is the Octy estate vrs petrol circa 2007.

I'm going to be doing 18,000 miles a year and will be keeping the car for 5 years so seriously considering converting it to LPG. My local fitter has converted other TSI engines but not the 2 litre TFSI so he is finding out for me from Prins if it definitely can be done.

From what I have picked up Prins seem to be the gold standard of LPG injectors and have only recently released their product to convert TSI engines. With converted TSI engines what normally happens is that they start on petrol then switch to LPG once warmed up - after about 1-2minutes. The car then runs solely on LPG until reaching about 4,500rpm when it will also start to inject some liquid petrol to help cool the cylinders.

I read of MPM's recent failed conversion with his BRC SDI kit. Possibly it was not set up correctly.

Can TFSI engines be converted. Any more info on converting the 2.0 TFSI in the VRS to LPG? Anybody tried the Prins conversion?

Many thanks in advance!

Edited 1 June, 2011 by lloydy123

[chr1staylor]

Welcome.

Just a minor, but possibly important wrt the LPG conversion point, a 2007 vRS will have a TFSI engine, some subtle differences over the new TSI engine (though a more knowledgeable person than I will explain what).

[D@z]

why not buy the diesel?

[gadgetman]

I don't think FSI or TFSI conversions are possible even now. Certainly still was the case when I looked into it about 3 months ago.

I know the newer TSI engines can be converted, but as you say can't run solely on LPG.

[lloydy123]

Good point Chr1staylor and Gadgetman! Sorry i need to edit my title. Are all petrol mark2 octavia VRS engines TFSI until present? When does the engine change?

Maybe I was quoting for a TSI engine.

[chrispy 2]

Good point Chr1staylor and Gadgetman! Sorry i need to edit my title. Are all petrol mark2 octavia VRS engines TFSI until present? When does the engine change?

Maybe I was quoting for a TSI engine.

To the best of my knowledge the Tsi in the vrs only came in for the face lift Or there may be the odd non F/L with one in. But the 07 I had was certainly a Tfsi. There are threads about when the Tsi started to be used on here somewhere. It will say on the engine cover though.

[FUBAR]

if you have had a test drive already have you tried the diesel??

[chrispy 2]

Hello Briskoda!!

I have been reading this site for quite a while although i only joined last night as I am seriously considering joining the Skoda family.

I have 2 requirements from a car - Needs to hold a lot of gear and needs to be a stimulating drive. Pretty clear to me that almost the only car that fits the bill is the Octy estate vrs petrol circa 2007.

I'm going to be doing 18,000 miles a year and will be keeping the car for 5 years so seriously considering converting it to LPG. My local fitter has converted other TSI engines but not the 2 litre TFSI so he is finding out for me from Prins if it definitely can be done.

From what I have picked up Prins seem to be the gold standard of LPG injectors and have only recently released their product to convert TSI engines. With converted TSI engines what normally happens is that they start on petrol then switch to LPG once warmed up - after about 1-2minutes. The car then runs solely on LPG until reaching about 4,500rpm when it will also start to inject some liquid petrol to help cool the cylinders.

I read of MPM's recent failed conversion with his BRC SDI kit. Possibly it was not set up correctly.

Can TFSI engines be converted. Any more info on converting the 2.0 TFSI in the VRS to LPG? Anybody tried the Prins conversion?

Many thanks in advance!

Have you had LPG before my inlaws got there Jeep done and its never been the same since. Plus where I live LPG is a pain to get. Is it worth changing it and possibly having a nightmare with the car afterwards or would it not be better paying out the extra for a diesel.

[RallyBoy]

If it's a 2.0L turbo then it's direct injection (TFSI / TSI). Talked about this with my LPG man and the issue with TFSI / TSI is that as the petrol injectors are in the head firing directly into the cylinder, if there's no fuel flowing they overheat. Hence people looking at LPG conversions on these engines are going effectively bi-fuel - most of the time it runs on LPG but every 200 cycles (or so) the petrol injectors fire to keep them cool - unlike earlier engines which start on petrol then changeover completely to LPG when warm.

In answer to the previous post, yes, it is worth it. I've now done 65000 since my conversion (1.8T) and have saved something like £3K after deducting the purchase price, servicing & Flashlube. The engine hasn't missed a beat in that time. At current prices, payback is about 20000 miles by my calcs.

Edited 1 June, 2011 by RallyBoy

[lloydy123]

OK, thanks Chrispy 2, doubt my budget would stretch to a facelifted model. I had a test drive in a diesel, it was very short and not not very enlightening. What puts me off diesel is the huge potential for expensive engine problems in cars aged 3-10 years - particulate filters, dual mass flywheels etc. I think the potential maintenance costs offset the increase in MPG. And probably not the same craic to drive on the limit.

I have an LPG station on my doorstep. I know 2 locals that have LPG Saab 9-5 Aeros that are going strong with over 1400000 miles which is encouraging. There are a lot of happy people on LPG but struggling to get feedback on this specific engine.

From what i gather the LPG injectors are inserted into the manifold as close to the head as possible.

That's another good point RallyBoy about the petrol injectors themselves needing to stay cool, although maybe that is part of the reason they operate above 4,500rpm. Did your LPG man seem relatively happy with the TFSI/TSI setup on LPG? Any feedback?

[lloydy123]

OK, looks like this can't be converted reliably yet :(

But i'll probably still get one and run it on petrol

[MPM]

I had mine converted and ended up removing the conversion as it just didn't work right....i'll see if i can find the link to the thread.

MPM

edit - found it Link to my LPG thread

Edited 13 June, 2011 by MPM

[rob_e]

The 1.8 TSI engine may be worth a look? Although quoted at 160PS (i think) they usually give a bit more, so performance won't be that far behind a vrs and you'll get better mpg?

[lloydy123]

Hi MPM, yes yours was the only example i found of a converted TFSI and it didn't fill me with confidence.

Sadly my budget won't stretch to a new shape TSI

[MPM]

The chap who did my conversion said that BRC are in the final stages of developing liquid injection of the gas - which would mean that most of my issues should be nullified due to the fuel getting to where it should when it should, at the right pressure. I think the main problem i had was my petrol is at ~100bar and the LPG was <5bar. Getting the fueling map to 'work' was nigh on impossible. (especially at low revs)

Fortunately, the technology is getting better all the time, however, the prices of LPG are getting WORSE all the time - again my LPG man conceeded that the 'easy' savings just aren't there anymore - you really need to be plugging the miles in.

MPM