Turbo - 5psi - No Intercooler
Discussion
One for the forced induction experts really....
What are your thoughts on Eann Whalley's Kit 1, ie his basic kit with no intercooler running low boost (5psi)?
My Canems engine management system gives me excellent control over fueling and ignition timing under boost, it also includes a number of boost safe strategies including air temp ignition correction and air temp fuel correction so I can further retard timing and add fuel in addition to my base forced induction map when/if there are spikes in air temp.
This plus the fact I'd be burning super detonation resistant 110Ron LPG.... obviously
My questions are....
Q1: "Would it be perfectly safe to run 'Ol Gasbag' on 5psi with no intercooler with the right boost map and air temp timing/fuel safety strategies to add a further margin of safety?"
Q2: Or is it a case or is it a case of .... "For the extra money, an intercooler is a no-brainer even at 5psi?"
Perhaps the answer lies somewhere in between, ie at 5psi the no intercooler strategy is fine, I can then add one at a later date if I choose to wind the boost up over say 7psi?
Finally, 'Ol Gasbag' is essentially an LPG fed 4.0HC with a V8D Stealth cam, a lightened flywheel, no cats and few other minor tweaks. Like this and with same heads the car came with from new in 1996 she makes 250hp and 263 ft/lbs burning LPG in her current normally aspirated sate, which I feel is a respectable result for a 4.0 litre on gas with no head work.
Q3: "Based on my current figures, what numbers should I expect after adding 5psi of boost?"
I was thinking if it gave me 305hp and 340ft/lbs I'd end up a 4.0 litre Chimaera that got down the road much like a fit 5.0 litre (if not a little better), but my hope is if I choose to stay out of the boost I can retain my current very practical LPG touring range of 307 miles and the game changing average 48mpg petrol cost equivalent economy too?
Running LPG has given me my cake and allowed me to eat it too, I'm just wondering if adding 5psi would give be a bigger slice of cake when I wanted to indulge myself..... without ruining my touring range and fuel economy when I'm watching my waistline
Answers and thoughts on this idea from the experienced boosted brigade are most welcome
Thanks, Dave
What are your thoughts on Eann Whalley's Kit 1, ie his basic kit with no intercooler running low boost (5psi)?
My Canems engine management system gives me excellent control over fueling and ignition timing under boost, it also includes a number of boost safe strategies including air temp ignition correction and air temp fuel correction so I can further retard timing and add fuel in addition to my base forced induction map when/if there are spikes in air temp.
This plus the fact I'd be burning super detonation resistant 110Ron LPG.... obviously
My questions are....
Q1: "Would it be perfectly safe to run 'Ol Gasbag' on 5psi with no intercooler with the right boost map and air temp timing/fuel safety strategies to add a further margin of safety?"
Q2: Or is it a case or is it a case of .... "For the extra money, an intercooler is a no-brainer even at 5psi?"
Perhaps the answer lies somewhere in between, ie at 5psi the no intercooler strategy is fine, I can then add one at a later date if I choose to wind the boost up over say 7psi?
Finally, 'Ol Gasbag' is essentially an LPG fed 4.0HC with a V8D Stealth cam, a lightened flywheel, no cats and few other minor tweaks. Like this and with same heads the car came with from new in 1996 she makes 250hp and 263 ft/lbs burning LPG in her current normally aspirated sate, which I feel is a respectable result for a 4.0 litre on gas with no head work.
Q3: "Based on my current figures, what numbers should I expect after adding 5psi of boost?"
I was thinking if it gave me 305hp and 340ft/lbs I'd end up a 4.0 litre Chimaera that got down the road much like a fit 5.0 litre (if not a little better), but my hope is if I choose to stay out of the boost I can retain my current very practical LPG touring range of 307 miles and the game changing average 48mpg petrol cost equivalent economy too?
Running LPG has given me my cake and allowed me to eat it too, I'm just wondering if adding 5psi would give be a bigger slice of cake when I wanted to indulge myself..... without ruining my touring range and fuel economy when I'm watching my waistline
Answers and thoughts on this idea from the experienced boosted brigade are most welcome
Thanks, Dave
For low boost an IC isn't needed imo. I'd get it up and running and go from there. A shot of WI is my preferred method as you never hold boost for very long. As for power predictions, maybe just over 300 hp and appx 350 lbs/ft.
As you know your lpg is very boost friendly so I suspect you'll be able to run at 9 psi maybe a tad more even on stock c/r. Then you may choose to fit an IC.
As you know your lpg is very boost friendly so I suspect you'll be able to run at 9 psi maybe a tad more even on stock c/r. Then you may choose to fit an IC.
Sardonicus said:
Just my cents Dave why would you not run an inter-cooler ? Why run hotter intake temps than necessary ?
Valid point Simon and the very debate I'm having with myself, as such it's exactly why I'm posting in the hope of getting some balanced views on the pros and cons. Eann Whalley's 5psi kit seems to have been designed for those still on the 14CUX, so running the no intercooler kit with my Canems engine management system surely only makes things easier and safer still..The argument actually goes two ways, but here's the 'no intercooler' side of my personal debate which I feel in my personal and rather unique situation earns itself a lot of merit points:
1. POWER & TORQUE TARGETS:
I don't need more than say 320hp and 360 ft/lbs, and from everything I've read it's unlikely I need more than 5psi to achieve these goals?
2. USING LOGIC:
I think its safe to assume Eann Whalley doesn't offer an intercooler with his 5psi kit because it doesn't need one, I also think its equally safe to assume Eann knows what he's doing as he's been boosting RV8 TVRs for years now.
3. LPG COMPONENTS:
In theory keeping things at 5psi means my current LPG hardware (Magic 3 Power vaporiser & LPG Tech Yeti injectors) can be retained with only a small pressure adjustment at the vaporiser and a conservative increase injector nozzle size. These components have a ceiling of 400 horse/torques, so keeping things at 5psi means I'm not forced to fit a second vaporiser and going to Yeti Big Flow injectors adding tuning complexity/cost.
4. COST & ENGINE LIFE:
Adding an additional vaporiser and the Yeti Big Flow injectors will add £300 to the conversion, Eann's intercooler kit is £600 more expensive than his 5psi kit without one, so in total I'd be saving £900 and still be able to hit my horsepower/torque targets while keeping things nice and safe and retaining engine longevity too.
4. SIMPLIFYING INSTALLATION COMPLEXITY:
Running an intercooler means more pipe work, I've studied this plumbing on intercooled turbo Chimaeras and it would definitely be in conflict with my vaporser location and LPG hose routing, if I fitted an intercooler I'd have to completely rethink my vaporiser location ect which while doable is a bit of a pain.
5. ECONOMY & TOURING RANGE:
In theory if I stay out of the boost I should retain my petrol cost equivalent 48mpg average and 307 mile touring range which makes the car so practical to use, I definitely wouldn't want to lose these advantages as it could start to impact on how often I use the car and limit the continental touring holidays I enjoy so much.
SUMMARY:
The idea of 5psi boosting 'Ol Gasbag' is it would take the car to the next level without introducing compromises in reliability, engine longevity or the excellent enhanced usability going LPG has given me. There is also a very strong argument that says LPG & boost are the perfect bedfellows as it's a super detonation resistant fuel which is just what you want when going forced induction, but due to it's voluminous nature it tends to displace air in the combustion chamber which is part of the reason you will always burn a bit more fuel when running on gas.
A small amount of boost means you are offsetting the fuel volume and air displacement disadvantage, cram air in above atmospheric pressure and the mix of air and LPG fuel becomes a more efficient recipe, essentially the volumetric efficiency improvements we see when boosting a petrol engine are even more pronounced on a gaseous LPG system to the extent where at cruising/low boost situations these efficiencies should actually translate to an improvement in fuel economy on gas.
On a boosted engine running petrol we tend to not only run a richer mixture to match the additional air charge density but we also throw in a bit more to help cool that charge down, this would be a pointless strategy on LPG as there is no cooling effect from the fuel. Even in 'Ol Gasbag's' current normally aspirated state and under full load there's very little point in running AFRs anything other than a fraction richer than stoich, LPG burns more completely than petrol too as being a gas it mixes better with air which obviously is another gas. All this means the 'richer under peak load' petrol rule simply doesn't apply to the same extent on LPG, indeed the richer you go with LPG the hotter it burns so pegging things to, or close to, lambda one is the preferred strategy in intelligent LPG tuning circles.
Going back to the 'intercooler or no intercooler' debate if I went for the intecooled 10psi kit things just get more complex and expensive as I'd be pushing my LPG components right to or even beyond their limit, with an intercooler in place I would already need to relocate my single vapoiser and if I was forced to run two vaporisers the under bonnet packaging headache becomes double the challenge.
My thinking is if I keep things modest at 5psi I'm confident my existing LPG injectors and single vaporiser arrangement will cope, with no intercooler the whole packaging challenge in my case becomes far less complex and saves me the best part of a grand in total which is not to be sniffed at. I'm confident the end result of forcing just 5psi down 'Ol Gasbag's' neck should be a noticeable but safe jump in my current output somewhere in the order of 300+ horsepower and 350+ ft/lbs of torque thus pushing the performance past that of a fit 5.0 litre Chimaera.
All that and in touring mode where the blower may only be huffing 1 or 2psi into the engine it could actually deliver a small increase in efficiency and so a small improvement in fuel economy too, so for a host of reasons and for a long time now I've been thinking Eann Whalley's no intercooler 5psi kit is just so perfect for 'Ol Gasbag' I would actually be mad not to add it
I was having this exact conversation with a customer the other week.
Low pressure, no intercooler, no real need for a dump valve even, integral wastegate to reduce plumbing/fabrication costs, 14cux remapped ..
this is the way I would go for a low cost simple install. Ebay turbo for under 150 pounds - plenty of people successfully using cheap ebay turbos on the forums .. I reckon you could probably do a self-build for under 600 pounds set up and mapped ??
Low pressure, no intercooler, no real need for a dump valve even, integral wastegate to reduce plumbing/fabrication costs, 14cux remapped ..
this is the way I would go for a low cost simple install. Ebay turbo for under 150 pounds - plenty of people successfully using cheap ebay turbos on the forums .. I reckon you could probably do a self-build for under 600 pounds set up and mapped ??
spitfire4v8 said:
I was having this exact conversation with a customer the other week.
Low pressure, no intercooler, no real need for a dump valve even, integral wastegate to reduce plumbing/fabrication costs, 14cux remapped ..
this is the way I would go for a low cost simple install. Ebay turbo for under 150 pounds - plenty of people successfully using cheap ebay turbos on the forums .. I reckon you could probably do a self-build for under 600 pounds set up and mapped ??
Hard to argue with that Jules Low pressure, no intercooler, no real need for a dump valve even, integral wastegate to reduce plumbing/fabrication costs, 14cux remapped ..
this is the way I would go for a low cost simple install. Ebay turbo for under 150 pounds - plenty of people successfully using cheap ebay turbos on the forums .. I reckon you could probably do a self-build for under 600 pounds set up and mapped ??
I am not an expert.....one install, done by the guy selling them, on an engine built by an expert to a design specified by an expert who knew I wanted to turbocharge it,, does not make me an expert.
The things I remember from the design of my engine was that it needed to be low compression, and with minimal valve opening overlap. Therefore mine is a Range Rover 4.6, with Range Rover cam and heads.
So you might want to find out how much valve overlap your stealth cam creates, and what compression ratio you might be running.
Intercooler or not....ask Eann.
My engine should have been 220 bhp as a standard RR 4.6. It made 372 bhp and 470 torques at 6 psi. I think you might be surprised how much yours makes at 5 psi, Dave.
Discuss.....
The things I remember from the design of my engine was that it needed to be low compression, and with minimal valve opening overlap. Therefore mine is a Range Rover 4.6, with Range Rover cam and heads.
So you might want to find out how much valve overlap your stealth cam creates, and what compression ratio you might be running.
Intercooler or not....ask Eann.
My engine should have been 220 bhp as a standard RR 4.6. It made 372 bhp and 470 torques at 6 psi. I think you might be surprised how much yours makes at 5 psi, Dave.
Discuss.....
QBee said:
I am not an expert.....one install, done by the guy selling them, on an engine built by an expert to a design specified by an expert who knew I wanted to turbocharge it,, does not make me an expert.
The things I remember from the design of my engine was that it needed to be low compression, and with minimal valve opening overlap. Therefore mine is a Range Rover 4.6, with Range Rover cam and heads.
So you might want to find out how much valve overlap your stealth cam creates, and what compression ratio you might be running.
Intercooler or not....ask Eann.
My engine should have been 220 bhp as a standard RR 4.6. It made 372 bhp and 470 torques at 6 psi. I think you might be surprised how much yours makes at 5 psi, Dave.
Discuss.....
Good post, valid points, thanks Anthony The things I remember from the design of my engine was that it needed to be low compression, and with minimal valve opening overlap. Therefore mine is a Range Rover 4.6, with Range Rover cam and heads.
So you might want to find out how much valve overlap your stealth cam creates, and what compression ratio you might be running.
Intercooler or not....ask Eann.
My engine should have been 220 bhp as a standard RR 4.6. It made 372 bhp and 470 torques at 6 psi. I think you might be surprised how much yours makes at 5 psi, Dave.
Discuss.....
I have a standard 4.0 HC (serp engine), I believe the compression ratio on all 4.0 litre Chimaeras is the same as a Range Rover of the day (9.35:1) but I'm happy to be corrected on this.
As for the overlap on the Stealth cam, well this is unknown as V8 Development don't advertise the detail spec of their cams, what they do say about it is the following....
The Stealth is a slightly more progressive fast road camshaft than the MC1. This is ideally suited to the 4.6 or 5.0 engine and the driver who is looking for a little more performance from their car. The camshaft produces valve lift which is just on the limit of fitting without pockets but we recommend pocketed pistons as a precautionary measure.Peak horsepower is seen at around 5,500 rpm and this cam still maintains good low rev manners and a steady idle. Double valve springs recommended.
The Stealth is a milder and more street friendly cam than the V8 Developments Track Day Cam which the describe as follows....
This is a slightly more 'radical' version of the Stealth camshaft. Peak power is at around 5,700 rpm and idle is slightly compromised on a standard injection system (aftermarket injection systems cope far better). The power output is substantially greater than the milder cams however and this makes an excellent track day camshaft. Hydraulic design. Requires double valve springs.
My Stealth certainly isn't a wild cam with lots of overlap, I ran it before switching to my Canems ECU and the car was perfectly drivable on the 14CUX, and if I'm right about my compression ratio being 9.35:1 then I wouldn't have thought just 5psi is an issue at all?
QBee said:
My engine should have been 220 bhp as a standard RR 4.6. It made 372 bhp and 470 torques at 6 psi. I think you might be surprised how much yours makes at 5 psi.
Ok lets do some maths 
...... 372 - 220 = 152 / 6psi = 25.33hp per 1psiSo if I add 5psi on top of my 250hp in theory I should get 126.66 + 250 = 376.66 horsepower which is plenty thank you very much.
I'm not even going to properly work out the torque as its clearly going to be mental
Saying that we can all get excited about top line numbers, of course what tells the true story is a dyno graph and a test drive
Looking at the IC routing on super/turbocharged Griffmaeras, I would most definitely forego the intercooler installation on one when at all feasible in favour of water injection, keeping the intake tract from turbo to throttle butterfly as short, simple and unrestricted as possible to salvage as much of the throttle response as possible.
In fact, that's what I would do if I'd build a Saab turbo right now...
In fact, that's what I would do if I'd build a Saab turbo right now...
spitfire4v8 said:
I was having this exact conversation with a customer the other week.
Low pressure, no intercooler, no real need for a dump valve even, integral wastegate to reduce plumbing/fabrication costs, 14cux remapped ..
this is the way I would go for a low cost simple install. Ebay turbo for under 150 pounds - plenty of people successfully using cheap ebay turbos on the forums .. I reckon you could probably do a self-build for under 600 pounds set up and mapped ??
Hmm, interested to know a bit more about this and if anyone has done it. Low pressure, no intercooler, no real need for a dump valve even, integral wastegate to reduce plumbing/fabrication costs, 14cux remapped ..
this is the way I would go for a low cost simple install. Ebay turbo for under 150 pounds - plenty of people successfully using cheap ebay turbos on the forums .. I reckon you could probably do a self-build for under 600 pounds set up and mapped ??
Dave, you asked for graphs.
The bottom one is 2.5 psi
Middle is 6 psi
Top is 7.5 psi
The torque scale is double the bhp scale, hence the lines are lower down the page but the torque is substantially higher than the bhp.
It drives just like my old stealth cammed V8D 5 litre engine used to. No noticeable lag at all, but you can drive it to see if you can detect any.
The bottom one is 2.5 psi
Middle is 6 psi
Top is 7.5 psi
The torque scale is double the bhp scale, hence the lines are lower down the page but the torque is substantially higher than the bhp.
It drives just like my old stealth cammed V8D 5 litre engine used to. No noticeable lag at all, but you can drive it to see if you can detect any.
So a key consideration with LPG is unlike petrol there is no cooling/lubricating effect, this is not really an issue if your valve seats are hard enough as they are with a Rover V8, this is one of the key reasons the Rover V8 is considered a gas friendly engine.
With forced induction contrary to common assumption intake temps will actually be hardly any different as this is a port injected engine, quite simply because the petrol is introduced close to the inlet valve the cooling properties of petrol have on air temps have less effect.
Introducing the petrol further upstream as with a carb or throttle body injection and things are very different, this is why water with water injection gets introduced upstream and sometimes directly into the compressor inlet itself to cool the air as it picks up heat from the process of being compressed.
In the world of LPG oil injection is common place and kits are readily available, a light oil is injected not to cool the inlet charge as with water injection but to cool and lubricate the inlet valve that can suffer recession if the valve seat metallurgy is not hard enough to cope without the lubricating and cooling qualities of a liquid fuel.
In summary if theres no intercooler water/meth injection is a fantastic solution for a forced induction engine burning LPG.
With forced induction contrary to common assumption intake temps will actually be hardly any different as this is a port injected engine, quite simply because the petrol is introduced close to the inlet valve the cooling properties of petrol have on air temps have less effect.
Introducing the petrol further upstream as with a carb or throttle body injection and things are very different, this is why water with water injection gets introduced upstream and sometimes directly into the compressor inlet itself to cool the air as it picks up heat from the process of being compressed.
In the world of LPG oil injection is common place and kits are readily available, a light oil is injected not to cool the inlet charge as with water injection but to cool and lubricate the inlet valve that can suffer recession if the valve seat metallurgy is not hard enough to cope without the lubricating and cooling qualities of a liquid fuel.
In summary if theres no intercooler water/meth injection is a fantastic solution for a forced induction engine burning LPG.
Edited by ChimpOnGas on Monday 15th April 22:21
ChimpOnGas said:
So a key consideration with LPG is unlike petrol there is no cooling/lubricating effect, this is not really an issue if your valve seats are hard enough as they are with a Rover V8, this is one of the key reasons the Rover V8 is considered a gas fr
Contrary to common assumption intake temps will actually be hardly any different as this is a port injected engine, quite simply because the petrol is introduced close to the inlet valve the cooling properties of petrol have less effect.
Introducing the petrol further upstream as with a carb or throttle body injection and things are very different, this is why water with water injection gets introduced upstream and sometimes directly into the compressor inlet itself to cool the air as it picks up heat from the process of being compressed.
In the world of LPG oil injection is common place and kits are readily available, a light oil is injected not to cool the inlet charge as with water injection but to cool and lubricate the inlet valve that can suffer recession if the valve seat metallurgy is not hard enough to cope without the lubricating and cooling qualities of a liquid fuel.
In summary if theres no intercooler water/meth injection is a fantastic solution on many counts.
Port injected, yeah I’d not thought about that but your summery is obviously correct. Very interesting post sir Contrary to common assumption intake temps will actually be hardly any different as this is a port injected engine, quite simply because the petrol is introduced close to the inlet valve the cooling properties of petrol have less effect.
Introducing the petrol further upstream as with a carb or throttle body injection and things are very different, this is why water with water injection gets introduced upstream and sometimes directly into the compressor inlet itself to cool the air as it picks up heat from the process of being compressed.
In the world of LPG oil injection is common place and kits are readily available, a light oil is injected not to cool the inlet charge as with water injection but to cool and lubricate the inlet valve that can suffer recession if the valve seat metallurgy is not hard enough to cope without the lubricating and cooling qualities of a liquid fuel.
In summary if theres no intercooler water/meth injection is a fantastic solution on many counts.
LPG now a Turbo,,, this guy is braver than astronauts
All of a sudden I quite like the lpg if you can make it fast
Proper cool dude even if a bit dangerous but in for a penny :Hehe:
I can’t see you spinning the turbo up enough to use it at 43 mpg or whatever it is,,,,,,
I love this idea using lpg.
Impressive if you can make it work.
Makes me think anything’s possible
Go for it man.
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