ACR Powerplus Land rover Series 2.25 2.5 Petrol 17H swap / conversion.
Posted: Thu Feb 27, 2020 11:47 am
For Eric Frenken & Anke Verheyen .... and Ivo van der Linden 123
1) Land rover Series 17H ACR Powerplus Petrol 2.25/ 2.5 /2.8 Petrol swap / conversion.
Be aware, this is a tidied rewrite of a post I did with another forum.
This conversion isn't strictly an engine-swap, however it kinda’ comes under that heading. Broadly the same engine as the 'common or garden' 2.25, this conversion is as easy as it gets. More correctly an engine-replacement, the 2.5 Petrol really does, 'just drop in'. No welding/ cutting/ moving battery-trays etc etc. Everything lines up, everything bolts in.
You'll use the 2.25 engine-mounts, radiator top-hose fitting; in some instances swap to a Series starter; find a 12V feed for some variants of the 17H carb, and use the 17H petrol NRC9772 Swirl Pot.
Be sure to put in a fuel-filter if running the 17H native Weber, they've a reputation for fussiness for dirt. Optional: A Stage One V8 throttle cable (with Clevis-pin) NRC5494 (fits SU very well) & Defender pedal. Bring the exhaust downpipe forward. And that's about it.
Disregarded in favour of the usual suspects, a 2.5 17H shouldn't be. The 17H 2.5 Petrol offers the character of the 2.25, yet it's sweeter, smoother, more grunty and slightly more economical. Whisper quiet too. Add the icing on the cake, ACR's kit, and a Series leafer struggles to be better.
Despite being sold for what must be 20 odd years, ACR's kit is never the herd-choice. For those of you that don’t know, ACR make a gas-flowed head/cam/SU carb / extractor 'kit of parts' for 2.25/2.5 petrol engines. Branded Powerplus. Most add this kit to the 2.25 3MB because that'll be what they have. Any of the 4-pot 2.25 LR petrol engines will do. In my mind the ideal start-point is a 17H 5MB 2.5 petrol. I say this because you'll see 200Tdi/ Lower level V8 like grunt.
I've a 17H 2.5 and I run this with ACR’s over-size pistons. This takes the 2.5 5MB out to 2.8. There's another route to 2.5: this involves crank-swaps from the 200Tdi. Take a 2.25 5MB out to 2.5 (or even 2.8).
I notice ACR offer similar over-size pistons, these added to a 3MB 2.25 to bring 2.5 - favouring 5MB, no experience of these myself.
I certainly wasn't the first to do this conversion. Nonetheless a 2.5 Petrol is rare, and it shouldn't be. Even without adding the oomph from ACR parts, this swap is a beautiful thing. What baffles me is the number of rebuilds you'd see of the 2.25 in preference to the 2.5? The 2.5 is essentially the same engine. It's why ACR's kit fits either 2.5/2.25 5MB 17H/11H / 13H or any 2.25 3MB.
More on that in a mo'...
I can't stress enough, the 2.5 gives a smoother experience with gains not shown in the figures. I shall do my best to explain why you'll grow to love this solution.
https://www.automotivecomp.com
Engine-swaps
Anyone that’s done engine-swaps , and done them properly, knows swaps are not quick, or 'real-world cheap. Even if they appear so.
Nothing lines up, thus when doing a 'swap-proper' it's too tempting to lash them in. Mostly... they are. Yet, lash it in and we'll be doing it again. The bigger cost of all these swaps is the ancillaries. Custom exhausts etc. Never forget swaps will involve knocking-about. The damage done to anything decent is best avoided. Unless we intend to cock it in, a decent exhaust adds time and hassle, factor £700-900 to all the main swaps...
Except this one.
Most think it's the cost of finding an engine. If the engine is not the easy, quick and cheap bit, your swap is set to be yet another worthless bodge. See these on eBay now.
I’ve done all the favourites. Engine recommendations are like those TripAdvisor restaurant reviews, more about the reviewer than the restaurant. Every conversion comes as a compromise, and for me anyway, the 2.5 17H approach works best.
So why a 2.5/2.8?
I write this biased to use as a 'daily-driver'. My V8 swap was nice but more knocking-about than I wanted to repeat. The V8 was 'juicy', the heat irked, and the sound although lovely, is too loud and isn’t 'very leafer'. On paper, a V8 appears the go-to solution, the reality doesn't really work.
I had a 200Tdi about 7 years back. Apologies to its fans but the swap, for my use anyway makes no sense. Yes it went well, only no amount of engine-mounts or sound-proofing, meant I had to be deaf, or prefer to limit driving-time. A Tdi powered daily-driver, for my use is unpleasant. That is not to say a Tdi is wrong. If you want cheap grunt, it’s your weekend toy, and don’t intend to drive far; or have no need for a radio, it might be the way to go. I found the 200Tdi promises instant gratification yet self-defeats - I used to wear ear-muffs, the noise ruins the experience. Most of the pleasure and character that is 'leafer-ownership' is removed. Those that base engine-choice on economy when they're not going to drive the thing, must be wiser than me; the 200TDi kills the desire to drive. The 200TDi has many fans, for which, I’m sure it’s right.
However, this took me back to my favourite, I did my numbers and a 5MB Powerplus 2.8 worked out quicker and easier. Initially it's far, far more expensive, yet long-game, cheaper and more pleasant. With the exception of a 2.6L Sixer, I’ve ‘long-term’ driven, and more importantly... lived with them all. On the surface the others tend to look a good idea; I've found they might impress for five minutes, yet don't really work when it's 'long-game'. Where ultimate driveability is paramount, and real 'liveability', you'd be wanting a 2.5 17H - preferably ACR kitted. And that's it bottled, the V8 or Tdi loses an indefinite 'something'.
Here's how I did mine:
I started in dribs and drabs with the ACR SU kit near 15 years ago.
Just the carb kit, the head a year later. I’ve had the kit as a 2.5 for near 6 years. 2.8 recently. My biggest mistake was not to fit the whole shebang in one hit. Only it's pricey; and I didn't see why I should? In hindsight, if I had, I'd never have gone to Tdi.
For me, a 17H with ACR kit is the perfect conversion. Silent as an angel's fart, but torque-laden, its real benefit is how lazy the driving experience becomes. I’ve now gone all the way to 2.8, it pulls hills in top and is ‘on pace’ with a lower-level V8. It’s slightly faster than a Tdi but appears slower because there’s no stirring the box. With a Tdi you won't want to sit in a 200Tdi for long. You move slower to limit noise. This means a 17H is real-world vastly quicker via its quietness, and the wider, lazier power delivery. Low-speed or off-road, the wider delivery knocks spots off my Tdi.
Family owned from new this 109 I do roughly 9000 a year, and it’s a real winner. Much as I ever did, I potter about at a max of 55-60mph. 55mph is about the comfortable speed for a Series regardless of how much grunt you have. A V8 or Tdi suits many, and I realise this solution sits on the fringe of the fringe. I doubt it’d suit the majority. Like as not, that's another reason it finds favour with me - precisely because it's never been the herd-choice. It's how the quiet grunt gets delivered. It’s also the whole experience which for me is pretty much the whole point of ownership. My mother or father, and my grandfather would use our leafer, listening to Radio 4 whilst we'd chat on the school-run. I do this now, with my own son.
Sentimentality is in the mix, yet cold-reasoning figures too. I run gas, and Homefill means a Tdi comes dearer to fuel. Which takes me back to sentimentality, a Tdi or V8, neither fits my mind’s eye of how our family-leafer should feel anyway. The standard swaps are somehow alien, and the overall effect leaves you to think: “Yes, but why?” I accept that’s very personal to me.
Near 20 years back, ACR were first to market. Understandably, Turner’s derided it. To a conservative customer-base, not truly understanding what ACR were doing, this was always going to be easy. These days, Turner’s - I suspect through gritted-teeth - make a muffled salute to the idea, they produce their own.
Most of you like a diesel. Quiet is my thing, this petrol is super-smooth, properly quiet and grunty. It's a 'daily'. Fuelling with gas via Homefill, makes it cheap to run.
I wrote before; Roland, the chap at ACR is a brilliant engineer, and his words are always right on it. I'll never quite grasp how Turner's are given the edge. Speak to them and it's soon very apparent they are machinists - if capable ones. Years back in the forums, the two went hammer and tongs at each other. Turner's decried the ACR approach, words to the effect that working what is essentially a block designed for diesel stresses is, all wrong, risky etc etc. This didn't stand scrutiny then, and time has borne this out. With my set-up I gather I must live in fear of things falling to bits... Ahem, where we move the goalposts slightly, the 5MB crank sits in a 200Tdi for chrissakes. It's the same part - more on that later.
One thing is true - Messrs Turner better understands the hide-bound mindset of the 'beard-brigade' customer-base. The customer-base thinks the ACR kit attempts to make a Series Land rover into a hot-hatch. These engines will never be road-burners, yet Roland’s full kit turns the page. These days, save the hard bit, that glorious cam, Turner's grant a big fat endorsement to Roland's approach, with their own version. Says it all really.
My mistake with this kit was to work in dribs and drabs, the kit really comes on song when you’ve removed each bottle-neck to air, and there's several. If you don’t, improvements are there, but with the other restrictions in place, you’ll not see 'bang-for-buck'. You're left wishing you’d gone the extra mile. For example, boy-racer 'more petrol innit' science says do a carb-swap. Unless your current example is worn, this alone can't work, and won't give bang-for-buck. The bottle-necks to an air-increase - and thus power - sit in your cam and head. Swapping a carb and thus metering the self-same air can't work. All you'll ever see is the power you were supposed to have.
How to cheat yourself?:
Run the cam and big pistons too. Don’t half-bake it, because failing to go the next notch won’t make you happy. You’ll feel you've cheated yourself. For ages I had everything fitted, but the cam. Yet, cam fitted, the other stuff comes alive. Most misunderstand what Roland is saying, and what this does. His development of this engine allows the head-work to breath right across the rev-range. The change is pure genius. Unlike a Tdi, which has you box-stirring for the impression of speed, the cam gives a wide spread of power. It’s the trick everybody misses, it becomes very driveable. Pull a hill-start from 500rpm. Sail up pretty much any hill in top, without ear-defenders. The cam/head does move peak power up by 200-300 rpm, yet most dullard the obvious. In putting out more power, there's more at the bottom. At low rpm you’ll leave a 2.25 petrol for dust. Where there is an rpm increase, it'll be because you're going faster. Thus you don't have to rev. I don't drive that way, and most of us don't. The reality has you going up hills in a higher gear, rpm is lower or identical. Unless you insist.
Be minded to why the late 2.5 5MB has extra grunt - it’s in its breathing and cam.
Land rover's final development of this engine, even in stock form the 2.5 5MB engine and its long-stroke format makes a real difference not seen in the figures. Don't under-estimate the extra torque and its usefulness. The extra power is not all about extra capacity. If it was, we'd see higher fuel-consumption. If anything, the 2.5 uses slightly less fuel. The 17H breathes better. Put a stock 200Tdi/2.5 cam [same part shared] in a 2.25, and this alone makes a difference. The head/carb and exhaust is better too.
1) Land rover Series 17H ACR Powerplus Petrol 2.25/ 2.5 /2.8 Petrol swap / conversion.
Be aware, this is a tidied rewrite of a post I did with another forum.
This conversion isn't strictly an engine-swap, however it kinda’ comes under that heading. Broadly the same engine as the 'common or garden' 2.25, this conversion is as easy as it gets. More correctly an engine-replacement, the 2.5 Petrol really does, 'just drop in'. No welding/ cutting/ moving battery-trays etc etc. Everything lines up, everything bolts in.
You'll use the 2.25 engine-mounts, radiator top-hose fitting; in some instances swap to a Series starter; find a 12V feed for some variants of the 17H carb, and use the 17H petrol NRC9772 Swirl Pot.
Be sure to put in a fuel-filter if running the 17H native Weber, they've a reputation for fussiness for dirt. Optional: A Stage One V8 throttle cable (with Clevis-pin) NRC5494 (fits SU very well) & Defender pedal. Bring the exhaust downpipe forward. And that's about it.
Disregarded in favour of the usual suspects, a 2.5 17H shouldn't be. The 17H 2.5 Petrol offers the character of the 2.25, yet it's sweeter, smoother, more grunty and slightly more economical. Whisper quiet too. Add the icing on the cake, ACR's kit, and a Series leafer struggles to be better.
Despite being sold for what must be 20 odd years, ACR's kit is never the herd-choice. For those of you that don’t know, ACR make a gas-flowed head/cam/SU carb / extractor 'kit of parts' for 2.25/2.5 petrol engines. Branded Powerplus. Most add this kit to the 2.25 3MB because that'll be what they have. Any of the 4-pot 2.25 LR petrol engines will do. In my mind the ideal start-point is a 17H 5MB 2.5 petrol. I say this because you'll see 200Tdi/ Lower level V8 like grunt.
I've a 17H 2.5 and I run this with ACR’s over-size pistons. This takes the 2.5 5MB out to 2.8. There's another route to 2.5: this involves crank-swaps from the 200Tdi. Take a 2.25 5MB out to 2.5 (or even 2.8).
I notice ACR offer similar over-size pistons, these added to a 3MB 2.25 to bring 2.5 - favouring 5MB, no experience of these myself.
I certainly wasn't the first to do this conversion. Nonetheless a 2.5 Petrol is rare, and it shouldn't be. Even without adding the oomph from ACR parts, this swap is a beautiful thing. What baffles me is the number of rebuilds you'd see of the 2.25 in preference to the 2.5? The 2.5 is essentially the same engine. It's why ACR's kit fits either 2.5/2.25 5MB 17H/11H / 13H or any 2.25 3MB.
More on that in a mo'...
I can't stress enough, the 2.5 gives a smoother experience with gains not shown in the figures. I shall do my best to explain why you'll grow to love this solution.
https://www.automotivecomp.com
Engine-swaps
Anyone that’s done engine-swaps , and done them properly, knows swaps are not quick, or 'real-world cheap. Even if they appear so.
Nothing lines up, thus when doing a 'swap-proper' it's too tempting to lash them in. Mostly... they are. Yet, lash it in and we'll be doing it again. The bigger cost of all these swaps is the ancillaries. Custom exhausts etc. Never forget swaps will involve knocking-about. The damage done to anything decent is best avoided. Unless we intend to cock it in, a decent exhaust adds time and hassle, factor £700-900 to all the main swaps...
Except this one.
Most think it's the cost of finding an engine. If the engine is not the easy, quick and cheap bit, your swap is set to be yet another worthless bodge. See these on eBay now.
I’ve done all the favourites. Engine recommendations are like those TripAdvisor restaurant reviews, more about the reviewer than the restaurant. Every conversion comes as a compromise, and for me anyway, the 2.5 17H approach works best.
So why a 2.5/2.8?
I write this biased to use as a 'daily-driver'. My V8 swap was nice but more knocking-about than I wanted to repeat. The V8 was 'juicy', the heat irked, and the sound although lovely, is too loud and isn’t 'very leafer'. On paper, a V8 appears the go-to solution, the reality doesn't really work.
I had a 200Tdi about 7 years back. Apologies to its fans but the swap, for my use anyway makes no sense. Yes it went well, only no amount of engine-mounts or sound-proofing, meant I had to be deaf, or prefer to limit driving-time. A Tdi powered daily-driver, for my use is unpleasant. That is not to say a Tdi is wrong. If you want cheap grunt, it’s your weekend toy, and don’t intend to drive far; or have no need for a radio, it might be the way to go. I found the 200Tdi promises instant gratification yet self-defeats - I used to wear ear-muffs, the noise ruins the experience. Most of the pleasure and character that is 'leafer-ownership' is removed. Those that base engine-choice on economy when they're not going to drive the thing, must be wiser than me; the 200TDi kills the desire to drive. The 200TDi has many fans, for which, I’m sure it’s right.
However, this took me back to my favourite, I did my numbers and a 5MB Powerplus 2.8 worked out quicker and easier. Initially it's far, far more expensive, yet long-game, cheaper and more pleasant. With the exception of a 2.6L Sixer, I’ve ‘long-term’ driven, and more importantly... lived with them all. On the surface the others tend to look a good idea; I've found they might impress for five minutes, yet don't really work when it's 'long-game'. Where ultimate driveability is paramount, and real 'liveability', you'd be wanting a 2.5 17H - preferably ACR kitted. And that's it bottled, the V8 or Tdi loses an indefinite 'something'.
Here's how I did mine:
I started in dribs and drabs with the ACR SU kit near 15 years ago.
Just the carb kit, the head a year later. I’ve had the kit as a 2.5 for near 6 years. 2.8 recently. My biggest mistake was not to fit the whole shebang in one hit. Only it's pricey; and I didn't see why I should? In hindsight, if I had, I'd never have gone to Tdi.
For me, a 17H with ACR kit is the perfect conversion. Silent as an angel's fart, but torque-laden, its real benefit is how lazy the driving experience becomes. I’ve now gone all the way to 2.8, it pulls hills in top and is ‘on pace’ with a lower-level V8. It’s slightly faster than a Tdi but appears slower because there’s no stirring the box. With a Tdi you won't want to sit in a 200Tdi for long. You move slower to limit noise. This means a 17H is real-world vastly quicker via its quietness, and the wider, lazier power delivery. Low-speed or off-road, the wider delivery knocks spots off my Tdi.
Family owned from new this 109 I do roughly 9000 a year, and it’s a real winner. Much as I ever did, I potter about at a max of 55-60mph. 55mph is about the comfortable speed for a Series regardless of how much grunt you have. A V8 or Tdi suits many, and I realise this solution sits on the fringe of the fringe. I doubt it’d suit the majority. Like as not, that's another reason it finds favour with me - precisely because it's never been the herd-choice. It's how the quiet grunt gets delivered. It’s also the whole experience which for me is pretty much the whole point of ownership. My mother or father, and my grandfather would use our leafer, listening to Radio 4 whilst we'd chat on the school-run. I do this now, with my own son.
Sentimentality is in the mix, yet cold-reasoning figures too. I run gas, and Homefill means a Tdi comes dearer to fuel. Which takes me back to sentimentality, a Tdi or V8, neither fits my mind’s eye of how our family-leafer should feel anyway. The standard swaps are somehow alien, and the overall effect leaves you to think: “Yes, but why?” I accept that’s very personal to me.
Near 20 years back, ACR were first to market. Understandably, Turner’s derided it. To a conservative customer-base, not truly understanding what ACR were doing, this was always going to be easy. These days, Turner’s - I suspect through gritted-teeth - make a muffled salute to the idea, they produce their own.
Most of you like a diesel. Quiet is my thing, this petrol is super-smooth, properly quiet and grunty. It's a 'daily'. Fuelling with gas via Homefill, makes it cheap to run.
I wrote before; Roland, the chap at ACR is a brilliant engineer, and his words are always right on it. I'll never quite grasp how Turner's are given the edge. Speak to them and it's soon very apparent they are machinists - if capable ones. Years back in the forums, the two went hammer and tongs at each other. Turner's decried the ACR approach, words to the effect that working what is essentially a block designed for diesel stresses is, all wrong, risky etc etc. This didn't stand scrutiny then, and time has borne this out. With my set-up I gather I must live in fear of things falling to bits... Ahem, where we move the goalposts slightly, the 5MB crank sits in a 200Tdi for chrissakes. It's the same part - more on that later.
One thing is true - Messrs Turner better understands the hide-bound mindset of the 'beard-brigade' customer-base. The customer-base thinks the ACR kit attempts to make a Series Land rover into a hot-hatch. These engines will never be road-burners, yet Roland’s full kit turns the page. These days, save the hard bit, that glorious cam, Turner's grant a big fat endorsement to Roland's approach, with their own version. Says it all really.
My mistake with this kit was to work in dribs and drabs, the kit really comes on song when you’ve removed each bottle-neck to air, and there's several. If you don’t, improvements are there, but with the other restrictions in place, you’ll not see 'bang-for-buck'. You're left wishing you’d gone the extra mile. For example, boy-racer 'more petrol innit' science says do a carb-swap. Unless your current example is worn, this alone can't work, and won't give bang-for-buck. The bottle-necks to an air-increase - and thus power - sit in your cam and head. Swapping a carb and thus metering the self-same air can't work. All you'll ever see is the power you were supposed to have.
How to cheat yourself?:
Run the cam and big pistons too. Don’t half-bake it, because failing to go the next notch won’t make you happy. You’ll feel you've cheated yourself. For ages I had everything fitted, but the cam. Yet, cam fitted, the other stuff comes alive. Most misunderstand what Roland is saying, and what this does. His development of this engine allows the head-work to breath right across the rev-range. The change is pure genius. Unlike a Tdi, which has you box-stirring for the impression of speed, the cam gives a wide spread of power. It’s the trick everybody misses, it becomes very driveable. Pull a hill-start from 500rpm. Sail up pretty much any hill in top, without ear-defenders. The cam/head does move peak power up by 200-300 rpm, yet most dullard the obvious. In putting out more power, there's more at the bottom. At low rpm you’ll leave a 2.25 petrol for dust. Where there is an rpm increase, it'll be because you're going faster. Thus you don't have to rev. I don't drive that way, and most of us don't. The reality has you going up hills in a higher gear, rpm is lower or identical. Unless you insist.
Be minded to why the late 2.5 5MB has extra grunt - it’s in its breathing and cam.
Land rover's final development of this engine, even in stock form the 2.5 5MB engine and its long-stroke format makes a real difference not seen in the figures. Don't under-estimate the extra torque and its usefulness. The extra power is not all about extra capacity. If it was, we'd see higher fuel-consumption. If anything, the 2.5 uses slightly less fuel. The 17H breathes better. Put a stock 200Tdi/2.5 cam [same part shared] in a 2.25, and this alone makes a difference. The head/carb and exhaust is better too.