'Ol Gasbag' On the rollers - The 250hp -- 45mpg TVR
Discussion
A 250hp 4.0 litre V8 that does 45mpg, now that's what I call progress!
I'd like to think this is a healthy result for any 4.0 litre Rover V8 with standard heads on petrol.
But here we're doing it on LPG at just £3.20 a gallon.
The truth is she's probably making a good 15-20hp more than the day she left the TVR factory on petrol 17 years ago, and it wouldn't have been doing the cost equivalent 45mpg back then
A proper full fat old school 155mph V8 sports car that does 0-60 in under 5 seconds.
And now with added Ford Fiesta fuel economy!!!
I'd like to think this is a healthy result for any 4.0 litre Rover V8 with standard heads on petrol.
But here we're doing it on LPG at just £3.20 a gallon.
The truth is she's probably making a good 15-20hp more than the day she left the TVR factory on petrol 17 years ago, and it wouldn't have been doing the cost equivalent 45mpg back then
A proper full fat old school 155mph V8 sports car that does 0-60 in under 5 seconds.
And now with added Ford Fiesta fuel economy!!!
Edited by ChimpOnGas on Tuesday 29th October 18:48
ChimpOnGas said:
A 250hp 4.0 litre V8 that does 45mpg, now that's what I call progress!
I'd like to think this is a healthy result for any 4.0 litre Rover V8 with standard heads on petrol.
But here we're doing it on LPG at just £3.20 a gallon.
The truth is she's probably making a good 15-20hp more than the day she left the TVR factory on petrol 17 years ago, and it wouldn't have been doing the cost equivalent 45mpg back then
A proper full fat old school 155mph V8 sports car that does 0-60 in under 5 seconds.
And now with added Ford Fiesta fuel economy!!!
Well done Dave well worth the effort!!!I'd like to think this is a healthy result for any 4.0 litre Rover V8 with standard heads on petrol.
But here we're doing it on LPG at just £3.20 a gallon.
The truth is she's probably making a good 15-20hp more than the day she left the TVR factory on petrol 17 years ago, and it wouldn't have been doing the cost equivalent 45mpg back then
A proper full fat old school 155mph V8 sports car that does 0-60 in under 5 seconds.
And now with added Ford Fiesta fuel economy!!!
Edited by ChimpOnGas on Tuesday 29th October 18:48
Have you tried reducing the Road Tax with the greener solution?
A900ss said:
Other than the LPG, what other engine mods have you done to extract 250hp from a 4.0? That's great power.
Not much really, the car is still on its standard cylinder heads which is what's holding it down at 250hp.The car runs the Canems dual fuel engine management system & a Stealth cam from Rob Robertson at V8 Developments.
Other than an ACT induction kit with a K&N air filter that's it, but the 110ron LPG had allowed us to run a lot more ignition advance, especially in the lower RPMs.
With better heads 270hp or more should be absolutely no problem.
But it's forced induction that's got my juices going, forget the heads and put the money into a supercharger and it should make 365hp on gas with no real impact on the fuel economy when cruising.
But hey, I'm getting ahead of myself again
ChimpOnGas said:
Not much really, the car is still on its standard cylinder heads which is what's holding it down at 250hp.
The car runs the Canems dual fuel engine management system & a Stealth cam from Rob Robertson at V8 Developments.
Other than an ACT induction kit with a K&N air filter that's it, but the 110ron LPG had allowed us to run a lot more ignition advance, especially in the lower RPMs.
With better heads 270hp or more should be absolutely no problem.
But it's forced induction that's got my juices going, forget the heads and put the money into a supercharger and it should make 365hp on gas with no real impact on the fuel economy when cruising.
But hey, I'm getting ahead of myself again
mmmm...thought you were going down the turbo routeThe car runs the Canems dual fuel engine management system & a Stealth cam from Rob Robertson at V8 Developments.
Other than an ACT induction kit with a K&N air filter that's it, but the 110ron LPG had allowed us to run a lot more ignition advance, especially in the lower RPMs.
With better heads 270hp or more should be absolutely no problem.
But it's forced induction that's got my juices going, forget the heads and put the money into a supercharger and it should make 365hp on gas with no real impact on the fuel economy when cruising.
But hey, I'm getting ahead of myself again
CHIMV8 said:
ChimpOnGas said:
Not much really, the car is still on its standard cylinder heads which is what's holding it down at 250hp.
The car runs the Canems dual fuel engine management system & a Stealth cam from Rob Robertson at V8 Developments.
Other than an ACT induction kit with a K&N air filter that's it, but the 110ron LPG had allowed us to run a lot more ignition advance, especially in the lower RPMs.
With better heads 270hp or more should be absolutely no problem.
But it's forced induction that's got my juices going, forget the heads and put the money into a supercharger and it should make 365hp on gas with no real impact on the fuel economy when cruising.
But hey, I'm getting ahead of myself again
mmmm...thought you were going down the turbo routeThe car runs the Canems dual fuel engine management system & a Stealth cam from Rob Robertson at V8 Developments.
Other than an ACT induction kit with a K&N air filter that's it, but the 110ron LPG had allowed us to run a lot more ignition advance, especially in the lower RPMs.
With better heads 270hp or more should be absolutely no problem.
But it's forced induction that's got my juices going, forget the heads and put the money into a supercharger and it should make 365hp on gas with no real impact on the fuel economy when cruising.
But hey, I'm getting ahead of myself again
I swing one way one day, and the other the next.
Did I tell you I swing both ways
ChimpOnGas said:
Not much really, the car is still on its standard cylinder heads which is what's holding it down at 250hp.
The car runs the Canems dual fuel engine management system & a Stealth cam from Rob Robertson at V8 Developments.
Other than an ACT induction kit with a K&N air filter that's it, but the 110ron LPG had allowed us to run a lot more ignition advance, especially in the lower RPMs.
With better heads 270hp or more should be absolutely no problem.
But it's forced induction that's got my juices going, forget the heads and put the money into a supercharger and it should make 365hp on gas with no real impact on the fuel economy when cruising.
But hey, I'm getting ahead of myself again
I am getting 350bhp with 10 boost, but going much higher pressure would decrease engine lifespan/risk very rapidly. The car runs the Canems dual fuel engine management system & a Stealth cam from Rob Robertson at V8 Developments.
Other than an ACT induction kit with a K&N air filter that's it, but the 110ron LPG had allowed us to run a lot more ignition advance, especially in the lower RPMs.
With better heads 270hp or more should be absolutely no problem.
But it's forced induction that's got my juices going, forget the heads and put the money into a supercharger and it should make 365hp on gas with no real impact on the fuel economy when cruising.
But hey, I'm getting ahead of myself again
TV8 said:
Hi Dave, good numbers but why was it on the rollers again?
The short answer is, we needed to change the injectors.The long answer is......
The original Keihin injectors I selected are very sophisticated , they worked great, gave excellent economy, drivability & power.
Actually the car made 261hp on the Keihins, but they run at very low impedance.
Unlike petrol saturated injectors, peak & hold LPG injectors send all the load back to the injector drivers housed in the ECU & that means heat!
The lower the impedance of the peak & hold injector the greater the load on the injector driver.
The Canems dual fuel ECU is mounted on a large aluminium heat sink to dissipate all this heat, but ultimately there's a limit to how much heat you can get rid of before the injector drivers get cooked.
The solution is to fit Magic Jet injectors, these are not really a true pintel type injector like the Keihins, as with all other LPG injectors the Magic Jets are more of a simple solenoid in fact.
In a way its a shame the Keihins didn't work out, when running they were exceptional, it's just things got too hot down at the ECU after long runs of anything more than 4 hours of sustained driving without a stop.
But we haven't given up on the Keihins just yet, there's some R&D going on up at Canems as we speak that could see them back on the car before long.
It's all in the electronics and how the heat can be dissipated, there are plenty of LPG piggy back ECUs out there like the Prins system that can easily cope with Keihins.
The challenge is actually far greater with the Canems system because everything in housed in one box, there's a lot less room than with a stand alone piggy back.
The Canems dual fuel ECU advantages are irrefutable, but the packaging advantage also presents the designer with some real challenges.
Its the same reason why its a ground breaking system and no one has done it before, or since.
So there's some Prins piggy back ECU evaluation going on at Canems to see how the Prins people do it, the next challenge will be to make it work in the single body Canems ECU housing.
But the truth is there's a much easier solution for now.
The boys at Lloyd Specialist Developments have been running their Range Rover on the Canems dual fuel ECU paired with Magic Jets for over two years with great performance, excellent economy & most importantly bullet proof reliability.
In fact from the outset they developed the dual fuel system in partnership with Canems to work specifically with Magic Jets.
Note to self,.... "Don't feck with a proven system"
My choice of Keihin injectors was always a bit of a step into the unknown, but it did have some sound research behind it and the idea wasn't rejected by Canems when we suggested it.
All the data suggests the Keihins should offer best in class efficiency, and they do, but the ECU needs to be able to cope with them first.
That's not far away, but for the time being it makes sense to just run Magic Jets for their compatibility with the ECU and the proven reliability this gives.
Apologies for the long answer, but changing the injectors alters other stuff & means a little bit more mapping is required.
But I think you'll agree looking at the above graph the Magic Jets still give nice power, and the economy should be excellent too.
So for now we've gone with the total proven reliability option of the Canems DF ECU & Magic Jet injector marriage.
Watch this space for even more power, paired with the same amazing Ford Fiesta fuel economy
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