Low Pressure Turbo Kit
Discussion
ClassiChimi said:
Buy it,, will you run the gas on it,, that's a daft question I'm sure 
Perfect for gas mate, LPG is 110Ron 
However, LPG is also a very voluminous fuel so it occupies more space than a liquid fuel like petrol.
It therefore tends to displace the air in the combustion chamber, and because you always need the right air fuel ratio no matter what fuel you're burning the voluminous nature of a gaseous fuel can result in a small reduction in performance.
In practice you can claw this lost performance back by taking advantage of the very high 110Ron octane and running more advance, in the end if you manage the ignition correctly you end up with the same power and actually a bit more torque on gas than petrol.
But what about if you could make that voluminous LPG smaller by compressing it, well that's a great idea but of course not very practical on a fuel injected vehicle.
So how about we compress the air instead
Now that's a great idea
And with 110Ron octane LPG the biggest danger of going forced induction (detonation) is actually far far less likely than on 95/98Ron petrol.
Finally.... it really doesn't matter what fuel you're burning if you are cramming more air in you'll need to add more of the fuel too, so all a forced induction engines will end up being less economical.
But I'm not really bothered about all that, because even if my LPG consumption falls to 15mpg it'll still be the same as a petrol car doing 30mpg.
Like I say, "LPG is perfect for forced induction"
I like it,,,I like it a lot,,, you make good sense Dave,,,,
If I'd done the France trip in the Chimaera 2600 miles and more by the time I get home at say 20 mpg ,,,,
That's a small fortune in itself
That's one of the things that's made me smile,,, I ride 200 miles or so then put 16 euros worth of petrol in the little tank and your off again,,
I'm going to keep the fuel receipts on the way back and calculate just how cheap it's been.
If I could get my car doing the kind of figures you can achieve on the Gas I'd never get out of it
For trips like these,, tight roads and changing gear all day not really ever getting upto silly speeds
It's making more sense every second.
My old Jaguar ran on petrol for years, only the 3.2 V8 but still drank the stuff
Soon as I went LPG it was as you've said before Dave half the price!
Ok so it cost a few quid to install but from that moment on my bank account had money in it
Your on to a winner yet again Dave,, your a clever boy so you are.
This is very interesting,,, I knew about the higher octane level and after reading your last post,,,,
I'll watch this with fingers crossed,,,
I'd like to keep my Chimaera for life,, this would be a way to ensure I do.
If I'd done the France trip in the Chimaera 2600 miles and more by the time I get home at say 20 mpg ,,,,
That's a small fortune in itself
That's one of the things that's made me smile,,, I ride 200 miles or so then put 16 euros worth of petrol in the little tank and your off again,,
I'm going to keep the fuel receipts on the way back and calculate just how cheap it's been.
If I could get my car doing the kind of figures you can achieve on the Gas I'd never get out of it
For trips like these,, tight roads and changing gear all day not really ever getting upto silly speeds
It's making more sense every second.
My old Jaguar ran on petrol for years, only the 3.2 V8 but still drank the stuff
Soon as I went LPG it was as you've said before Dave half the price!
Ok so it cost a few quid to install but from that moment on my bank account had money in it
Your on to a winner yet again Dave,, your a clever boy so you are.
This is very interesting,,, I knew about the higher octane level and after reading your last post,,,,
I'll watch this with fingers crossed,,,
I'd like to keep my Chimaera for life,, this would be a way to ensure I do.
Good on ya Alun, glad you get my back to front oddball way of doing things 
To be honest everything I've done to the car over the last few years has been about making it nicer to drive, more reliable, far more economical and ultimately more usable. I appreciate this isn't as sexy to read about as the more performance focused projects people present here it but I enjoy being different which is why I have massive respect for you and your recent amazing adventure.
I've been in the classic car world for a long time, the first thing I learned early on was that even the classics considered icons can be a huge disappointment to own and drive. Poor brakes, iffy handling, shocking reliability is often the reality of classic car ownership. If you like cars because you like driving the way I see it you either take something from the past and try to sympathetically update it, or you find something more modern with the character of something older that has most of the upgrades already.
That and my memories of the 90's Rover V8 TVRs when I was a young skint mechanic is what lead me to my Chimaera. It was and still is comparatively cheap to buy compared with something like a big Healey but so much better in every respect.
But to me a Chimaera could be made so much be better, I looked at the inherent reliability issues, the drivability failings and ultimately what was stopping me using the car more. The rest is history as they say.
I've seen a lot of people put all their focus into adding power only to find they've created a car that actually isn't all that nice to drive and one that consumes so much fuel they end up not driving it as much as they'd like.
Fast yes, makes big numbers on the rolling road yes, nice to drive & easy to live with.. absolutely not...
. So it spends more time sat in the garage than giving it's owner pleasure which is a crying a shame 
. Its also why I've always subscribed to the view point that you're far better off with a car that's nice to drive but has less power, because it'll be a car you actually use.
I wanted to reverse the well trodden "add power at all costs" path by first making my chosen classic more practical, reliable and nicer to drive. Only once all this had been achieved would I allow myself to move onto the fun bit of making it go faster.
Essentially I tried to focus on removing as many of the key TVR failings as I could, I'm not saying I've finished with all that but now I've got things more or less where I want them on the sensible side of things its time to look seriously at doing the fun bit most people start with....
Adding a bit more power
Lets just hope I dont completely undo all my good work so far
To be honest everything I've done to the car over the last few years has been about making it nicer to drive, more reliable, far more economical and ultimately more usable. I appreciate this isn't as sexy to read about as the more performance focused projects people present here it but I enjoy being different which is why I have massive respect for you and your recent amazing adventure.
I've been in the classic car world for a long time, the first thing I learned early on was that even the classics considered icons can be a huge disappointment to own and drive. Poor brakes, iffy handling, shocking reliability is often the reality of classic car ownership. If you like cars because you like driving the way I see it you either take something from the past and try to sympathetically update it, or you find something more modern with the character of something older that has most of the upgrades already.
That and my memories of the 90's Rover V8 TVRs when I was a young skint mechanic is what lead me to my Chimaera. It was and still is comparatively cheap to buy compared with something like a big Healey but so much better in every respect.
But to me a Chimaera could be made so much be better, I looked at the inherent reliability issues, the drivability failings and ultimately what was stopping me using the car more. The rest is history as they say.
I've seen a lot of people put all their focus into adding power only to find they've created a car that actually isn't all that nice to drive and one that consumes so much fuel they end up not driving it as much as they'd like.
Fast yes, makes big numbers on the rolling road yes, nice to drive & easy to live with.. absolutely not...
. So it spends more time sat in the garage than giving it's owner pleasure which is a crying a shame . Its also why I've always subscribed to the view point that you're far better off with a car that's nice to drive but has less power, because it'll be a car you actually use.I wanted to reverse the well trodden "add power at all costs" path by first making my chosen classic more practical, reliable and nicer to drive. Only once all this had been achieved would I allow myself to move onto the fun bit of making it go faster.
Essentially I tried to focus on removing as many of the key TVR failings as I could, I'm not saying I've finished with all that but now I've got things more or less where I want them on the sensible side of things its time to look seriously at doing the fun bit most people start with....
Adding a bit more power
Lets just hope I dont completely undo all my good work so far
OleVix said:
SILICONEKID345HP said:
Will that be another 50hp ?
make it another 100 Daz!
And in a car that weighs little more than a tonn you'll definitely feel that.
Especially the 100ft/lbs of torque
To put that into some sort of context it means my little 4.0 litre LPG converted Chimaera will make 325hp & 360 Ft/lbs of torque.
Compare this with the 2014 Griff Growl Rolling Road results...
| Name | Model | Modifications | BHP | Torque |
|---|---|---|---|---|
| eff eff | Griff 620 SE | LS3 6.2 Tremec TR6060 six speed box | 446 | 362 |
| Quinny | 400 Precat | Few bits n bobs and another mighty LS engine | 403.3 | 327.2 |
| phazed | 5.5 Interloper | Left handed angle bracket and strengthened swirl pot | 326.8 | 395 |
| ChimpOnGas | 4.0 Gas Sniffer | fantasy single turbo blowing a safe 5psi | 325 | 360 |
| pjac67 | 5.4 V8D | Feels alot quicker than my old 5.0 V8D which had higher figures... | 323.8 | 340 |
| P500OKO | Griff 500 | standard engine re-built 3k miles Austec Racing Mapped Mark Adams Bosh AFM and Injectors | 301.2 | 320 |
| Tavan | Griff 500 | Std engine, orig cam, 53K mls, 72mm plenum, riser & flared trumpets, no pussies, Megasquirt (fuel & wasted spark) | 300.8 | 320 |
| fastandcurious | Griff 500 | standard engine re-built with smooth bore induction kit, flared trumpet base & Power 885 cam | 300.3 | 285 |
| MPoxon | Griff 500 | Tornado chip, Bosch injectors, 3bar fuel reg, Bosch AFM, ACT Carbon Plenum, ACT Manifolds, Clive F decat Y-Piece, K&N Filter | 291.2 | 330 |
| Grngriff | Griff 430BV | Upgraded to BV with chip,decatted,carbon trumpets,smooth bore etc | 287.4 | 310 |
| SteveSprint | Precat 430 | Standard and well overdue a rebuild | 263.8 | 298 |
| lordrover | Ginger Ninja | sharkfin antenna | 180 | 145 |
That's all well and good but the real questions are..
- Is 5psi really low enough to safely not need an intercooler?
- Will it consume oil like knackered old Morris Minor?
- Will it blow it's seals?
- Will it blow it's exhaust manifold gaskets?
- Will the power delivery be lovely and predictable?
- Will I notice the turbo lag and end up frustrated by it?
- Will the engine remain reliable?
- Will it become the car I wish I'd never created?
Edited by ChimpOnGas on Tuesday 22 September 23:16
Not sure I'd agree with this comment
Fast yes, makes big numbers on the rolling road yes, nice to drive & easy to live with.. absolutely not..
Using the supercharger it drives smooth and no hump in the torque curve ! Mine will drive like a pussy cat , down to choice of cam etc, also fully sequential injection made a difference . Of course if a hairy chested medallion wearing cam is fitted I'd agree with your comment.
Fast yes, makes big numbers on the rolling road yes, nice to drive & easy to live with.. absolutely not..
Using the supercharger it drives smooth and no hump in the torque curve ! Mine will drive like a pussy cat , down to choice of cam etc, also fully sequential injection made a difference . Of course if a hairy chested medallion wearing cam is fitted I'd agree with your comment.
Edited by Hoofa on Wednesday 23 September 10:11
Not sure about Frankenstein Chilli, I guess its just a different way of doing things than the traditional large capacity normally aspirated rout that ultimately stops Rover V8 play around the 380hp (ish) mark.
And due to the elevated compression ratio of such builds means you'll never get to go forced induction even if you wanted to
I prefer to look at the proven engineering theory and predicted outcomes then base my modifications on them.
To this end all the theory suggests Eann Whalley's 5psi single Turbo starter kit should work really well on 'Ol Gasbag'.
The projected figures would speak for themselves:
And all that without the initial expense and added complication of an intercooler as the system will be only applying a very lowly and safe 5psi of boost to the engine.
Best of all there's huge scope for winding up the boost (to a still rather modest 10psi) and developing the car into something that will easily put down over 400 ft/lbs of torque.
But for me the target is a lovely driving super flexible old school performance car that doesn't drink oil, turn it's crank seals inside out or detonate it's pistons into moon crater landscape lookalikes. Yet retains that lovely LPG economy I've worked so hard to achieve.
For all these reasons the 5psi kit from Eann Whalley looks very very tempting indeed
And due to the elevated compression ratio of such builds means you'll never get to go forced induction even if you wanted to
I prefer to look at the proven engineering theory and predicted outcomes then base my modifications on them.
To this end all the theory suggests Eann Whalley's 5psi single Turbo starter kit should work really well on 'Ol Gasbag'.
The projected figures would speak for themselves:
- 325hp, making it faster than a standard 5.0 litre Chim or Griff by some considerable margin
- 1100kgs being moved along through town by 140 - 160 ft/lbs of torque between 1,500 to 2,000 RPM
- Torque rising rapidly to 220 ft/lbs by the time you reach just 2,500 RPM
- 360 ft/lbs all in but with a massive 90% of this peak torque being delivered at only 3,000 RPM
And all that without the initial expense and added complication of an intercooler as the system will be only applying a very lowly and safe 5psi of boost to the engine.
Best of all there's huge scope for winding up the boost (to a still rather modest 10psi) and developing the car into something that will easily put down over 400 ft/lbs of torque.
But for me the target is a lovely driving super flexible old school performance car that doesn't drink oil, turn it's crank seals inside out or detonate it's pistons into moon crater landscape lookalikes. Yet retains that lovely LPG economy I've worked so hard to achieve.
For all these reasons the 5psi kit from Eann Whalley looks very very tempting indeed
ChimpOnGas said:
Not sure about Frankenstein Chilli, I guess its just a different way of doing things than the traditional large capacity normally aspirated rout that ultimately stops Rover V8 play around the 380hp (ish) mark.
And due to the elevated compression ratio of such builds means you'll never get to go forced induction even if you wanted to
I prefer to look at the proven engineering theory and predicted outcomes then base my modifications on them.
To this end all the theory suggests Eann Whalley's 5psi single Turbo starter kit should work really well on 'Ol Gasbag'.
The projected figures would speak for themselves:
And all that without the initial expense and added complication of an intercooler as the system will be only applying a very lowly and safe 5psi of boost to the engine.
Best of all there's huge scope for winding up the boost (to a still rather modest 10psi) and developing the car into something that will easily put down over 400 ft/lbs of torque.
But for me the target is a lovely driving super flexible old school performance car that doesn't drink oil, turn it's crank seals inside out or detonate it's pistons into moon crater landscape lookalikes. Yet retains that lovely LPG economy I've worked so hard to achieve.
For all these reasons the 5psi kit from Eann Whalley looks very very tempting indeed
Can I have one please? Sounds perfect! Time to trade in the M3And due to the elevated compression ratio of such builds means you'll never get to go forced induction even if you wanted to
I prefer to look at the proven engineering theory and predicted outcomes then base my modifications on them.
To this end all the theory suggests Eann Whalley's 5psi single Turbo starter kit should work really well on 'Ol Gasbag'.
The projected figures would speak for themselves:
- 325hp, making it faster than a standard 5.0 litre Chim or Griff by some considerable margin
- 1100kgs being moved along through town by 140 - 160 ft/lbs of torque between 1,500 to 2,000 RPM
- Torque rising rapidly to 220 ft/lbs by the time you reach just 2,500 RPM
- 360 ft/lbs all in but with a massive 90% of this peak torque being delivered at only 3,000 RPM
And all that without the initial expense and added complication of an intercooler as the system will be only applying a very lowly and safe 5psi of boost to the engine.
Best of all there's huge scope for winding up the boost (to a still rather modest 10psi) and developing the car into something that will easily put down over 400 ft/lbs of torque.
But for me the target is a lovely driving super flexible old school performance car that doesn't drink oil, turn it's crank seals inside out or detonate it's pistons into moon crater landscape lookalikes. Yet retains that lovely LPG economy I've worked so hard to achieve.
For all these reasons the 5psi kit from Eann Whalley looks very very tempting indeed
carsy said:
The thing is tho Daz, you have the 345 at 6000rpm. Dave's turbo 345bhp will probably feel a lot faster with its torque coming in much lower in the rev range.
I could always fit one on my engine which would give ridiculous power but I`m not sure if the high comp might damage the engine .Those little 4l engines are very low compression so work well from standard form .
Hoofa said:
Using the supercharger it drives smooth and no hump in the torque curve!
Humping can be fun Nigel That's not an offer by the way
Question....is the power delivery on a low revving low compression ratio eight cylinder 4.0 litre engine really going to be that humpy if you're only blowing a very modest 5psi through it?
And while I freely admit I dont know much about managing turbo boost dynamics yet, surely these days its a very well understood science?
Now consider in addition to my very conservative goals my Canems engine management system has the facility to take full control of the bomb proof & ubiquitous Bosch N75J boost control solenoid, surely much if not all the undesirable hump effect can be effectively ironed out?
I would have thought assuming the right compressor pitch/size and hot side are carefully selected, assuming I keep the levels of boost to the very very modest 5psi, and assuming I properly manage that extremely limited boost with a well chosen waste gate & skilfully mapped Canems controlled boost control solenoid...I really can't see why the system couldn't be designed and configured to deliver the super smooth and predictable power delivery characteristics I seek.
The know how, components and control systems are not fantasy... they've been around for years and are very well understood, and lets not forget the essential engine management side is already in place on my car.
Considering all this does the power delivery really need to exhibit a hump?
Surely a skilled mapper using the Canems system and a boost control solenoid could intelligently build my boost curve to deliver exactly the drivability characteristics I'm looking for?
https://www.youtube.com/watch?v=TpdUBe2YJxQ
And all that's before we even start to play with the 3D ignition system to mask and smooth out any tiny peaks in the power delivery that may or may not still remain in order to artificially dial in a feeling that's very close indeed to a normally aspirated engine.
I'm a conservative guy, so I'd happily exchange 5hp and 10Ft/lbs of peak torque for a super smooth power delivery with none of those undesirable and well known turbo traits.
I'm a great believer in using technology to solve problems, so I really can't see why my objectives aren't totally achievable given my current engine management system, the skill of the mapping team I work with and we've chosen the turbo and boost management hardware wisely.
Maybe I'm over simplifying it, maybe I've not fully understood the boundaries of whats possible and how successful the results will be?
But I have a sneaking feeling given the knowledge, skills and modern technology that are available to me, a really nice driving 50mpg turbo Chimaera with modest boost is a perfectly achievable goal.
Edited by ChimpOnGas on Wednesday 23 September 12:42
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