Series 3 ACR PowerPlus Camshaft Specs

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tynker

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I’m considering putting an ACR Power Plus camshaft in my 2.25L engine. Before I do, I would like to be able to compare its specs to the existing 2.25L and 2.5L cams to see where and how it differs. I have all the specs (except lobe lift) for the stock 2.25L and 2.5L cams but not for the ACR cam. Does anyone have the actual cam card specifications for the ACR camshaft: IVO, IVC, IP, EVO, EVC, EP, LOBELIFT?
 
If I remember rightly, Turners Engineering, those fine purveyors of rebuilt series engines do not recommend 'tweeked' cam shafts. As a modest tuner of engines in the 70's and 80's, I agree with them. If you fit racing horse shoes to a cart horse, it will keep falling over.

Col
 
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If I remember rightly, Turners Engineering, those fine purveyors of rebuilt series engines do not recommend 'tweeked' cam shafts. As a modest tuner of engines in the 70's and 80's, I agree with them. If you fit racing horse shoes to a cart horse, it will keep falling over.

Col
 
If I remember rightly, Turners Engineering, those fine purveyors of rebuilt series engines do not recommend 'tweeked' cam shafts. As a modest tuner of engines in the 70's and 80's, I agree with them. If you fit racing horse shoes to a cart horse, it will keep falling over.

Col
 
I see where you are coming from. The Series engine is intended for smooth low speed slogging and most cams that up power do so by more lift and keeping the valves open longer. Longer valve opeing pushes power up the rev range and makes the engine rougher at low revs. I would look at what you can do to increase breathing first, then capacity, as these will both make for a nice to drive engine.
 
Makes me wonder how much one could spend on redesigning a 1940s engine so as to squeeze out a few extra horse power.
Then you realise Land Rover did it for you in later models. I prefer the original set up. There is something nice and errrrr, series about a series engine.
 
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A skim of the head to increase the compression ratio to 9:1 seems to be a cost effective way of getting a little more power from a 2.25. Then as rob1miles says a bit of careful porting of the head and a larger diameter exhaust to help it breath is a good option. I have heard good things of an SU carb and electronic ignition also. You also have to increase the gearing somehow.
A well sorted 2.25 petrol in a light vehicle (get rid or unnecessary weight) is an acceptable performer even in today's traffic.
 
A skim of the head to increase the compression ratio to 9:1 seems to be a cost effective way of getting a little more power from a 2.25. Then as rob1miles says a bit of careful porting of the head and a larger diameter exhaust to help it breath is a good option. I have heard good things of an SU carb and electronic ignition also. You also have to increase the gearing somehow.
A well sorted 2.25 petrol in a light vehicle (get rid or unnecessary weight) is an acceptable performer even in today's traffic.
 
Really agree with you re electroninc ignition; older engines are rarely set up right and it can be a revelation when they have reliable timeing and a decent carb. I also agree about weight, pity I'm not so good at doing it! I was talking to a guy who was prepping a car for track days, I asked what they found the best mod with the least effort. He said "taking out the interior and everything it doesn't need - better acceleration and handling and very cheap to do". Not that there is much to take ouf of a series. I think we have 1/2 ton of gear that could be removed....(we were weighed at 2 1/4 tons recently).
 
I had a modestly tuned two and a quarter,much as described by Cunkbucket. It was a nice extra boost without being silly. The SU carb although fine on the road was no good off road when one was at an angle.
 
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Thanks for all the feedback. I'm leery about over/mis-caming the engine. The 2.5L camshaft timing is the same as that specified for a 2.25L (8:1) only retarded by 5deg. Nothing terribly magical about that. So I wondered what ACR really did when they created this new grind that they claim is a better upgrade than just dropping in a 2.5L cam.
 
If I remember rightly, Turners Engineering, those fine purveyors of rebuilt series engines do not recommend 'tweeked' cam shafts. As a modest tuner of engines in the 70's and 80's, I agree with them. If you fit racing horse shoes to a cart horse, it will keep falling over.

Col
Yes, but under scrutiny, does this make sense? And if I recall that nugget was taken from a spat 15 odd years back that Turners had with their competitor ACR. Clearly Turner's had an axe to grind, and today, the 'said' nugget of wisdom can be seen for what it is. It's not stood well to history has it? ACR have a very good reputation. I have the full ACR Powerplus kit and it's brilliant. If it is ever going to leave a pile of bits in my wake, it hasn't happened yet. Maybe it's because I've not tried, but t'interweb forums should have seen plenty of tales of destruction by now. What ACR were saying comes good, the point was that also being a 'deseasel' lump, it's so under-stressed. It is. And with a choice of three, how would you mis-cam it anyway?

I have ACR's cam. Mine is the full ACR Powerplus kit with SU, cam, Stage 2 head and manglefold. It's a quiet civilised vehicle used as a daily driver. The low to middle-range grunt the kit gives is V8 like. Goes up any hill. And without the hassles, it really is bolt-on. Those that don't understand, think it makes for a racer. The increase in grunt comes across the range, and with a light foot I get a small improvement in mileage. The only two issues I've got with it, is that a leaden foot can be costly. But then it's going to be, a leafer is heavy. My other beef is the kit price, but then I'm tight.

It still works out cheaper than a Tdi or V8 swap (they only look cheap) and is far easier. With unmolested leafers at 'classic' status these days, the Tdi craze is slowing. It's already happening, blokes are taking 'em back out again. It's a very noisy conversion, so maybe better suited to weekend toys and the deaf. However, ACR kits on eBay get near what you pay for them, because those that have them don't sell 'em! Whereas a Tdi conversion makes you take a hit on the whole vehicle when on eBay, and you'll see lot os those lashed in, and selling cheap. Your price goes down, not up. A V8 is nice but you've gotta knock things about, and bulkheads aren't cheap or a strong-point. You won't see your money back on it.

The ACR kit is bolt-on / bolt-off and works. Simple. I run mine on a BLOS. I started out with just the SU carb jobby. No one conversion is perfect, but for me, especially if you can find a 5MB 2.5, as mine, factoring the overall and not just the headline-rate. Start and finish, looking at it hard, it's the way to go.

'Judging by what sells, I'd say they have it wrong. 'They' will poo-poo everything I've said, there's a hundred blokes with the usual conversions - I'm outnumbered.

I'd counter that those are the vehicles selling cheap, and the more worthwhile your vehicle, the more the point is valid. Of course, if your vehicle isn't worthwhile.... but best I declare defeat now.
 
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Well I'm not poo-pooing, I think the days of the TDI are numbered. I would certianly not be taking a 2 1/4 petrol out for a TDI now, its looking like a step in the wrong direction and has the elments of a fad. Lets see how resellable TDIs are over 2 1/4 petrols in a few years.
 
Yes, but under scrutiny, does this make sense? And if I recall that nugget was taken from a spat 15 odd years back that Turners had with their competitor ACR. Clearly Turner's had an axe to grind, and today, the 'said' nugget of wisdom can be seen for what it is. It's not stood well to history has it? ACR have a very good reputation. I have the full ACR Powerplus kit and it's brilliant. If it is ever going to leave a pile of bits in my wake, it hasn't happened yet. Maybe it's because I've not tried, but t'interweb forums should have seen plenty of tales of destruction by now. What ACR were saying comes good, the point was that also I'm being a 'deseasel' lump, it's so under-stressed. It is. And with a choice of three, how would you mis-cam it anyway?

I have ACR's cam. Mine is the full ACR Powerplus kit with SU, cam, Stage 2 head and manglefold. It's a quiet civilised vehicle used as a daily driver. The low to middle-range grunt the kit gives is V8 like. Goes up any hill. And without the hassles, it really is bolt-on. Those that don't understand, think it makes for a racer. The increase in grunt comes across the range, and with a light foot I get a small improvement in mileage. The only two issues I've got with it, is that a leaden foot can be costly. But then it's going to be, a leafer is heavy. My other beef is the kit price, but then I'm tight.

It still works out cheaper than a Tdi or V8 swap (they only look cheap) and is far easier. With unmolested leafers at 'classic' status these days, the Tdi craze is slowing. It's already happening, blokes are taking 'em back out again. It's a very noisy conversion, so maybe better suited to weekend toys and the deaf. However, ACR kits on eBay get near what you pay for them, because those that have them don't sell 'em! Whereas a Tdi conversion makes you take a hit on the whole vehicle when on eBay, and you'll see lot os those lashed in, and selling cheap. Your price goes down, not up. A V8 is nice but you've gotta knock things about, and bulkheads aren't cheap or a strong-point. You won't see your money back on it.

The ACR kit is bolt-on / bolt-off and works. Simple. I run mine on a BLOS. I started out with just the SU carb jobby. No one conversion is perfect, but for me, especially if you can find a 5MB 2.5, as mine, factoring the overall and not just the headline-rate. Start and finish, looking at it hard, it's the way to go.

'Judging by what sells, I'd say they have it wrong. 'They' will poo-poo everything I've said, there's a hundred blokes with the usual conversions - I'm outnumbered.

I'd counter that those are the vehicles selling cheap, and the more worthwhile your vehicle, the more the point is valid. Of course, if your vehicle isn't worthwhile.... but best I declare defeat now.
Yes, but under scrutiny, does this make sense? And if I recall that nugget was taken from a spat 15 odd years back that Turners had with their competitor ACR. Clearly Turner's had an axe to grind, and today, the 'said' nugget of wisdom can be seen for what it is. It's not stood well to history has it? ACR have a very good reputation. I have the full ACR Powerplus kit and it's brilliant. If it is ever going to leave a pile of bits in my wake, it hasn't happened yet. Maybe it's because I've not tried, but t'interweb forums should have seen plenty of tales of destruction by now. What ACR were saying comes good, the point was that also being a 'deseasel' lump, it's so under-stressed. It is. And with a choice of three, how would you mis-cam it anyway?

I have ACR's cam. Mine is the full ACR Powerplus kit with SU, cam, Stage 2 head and manglefold. It's a quiet civilised vehicle used as a daily driver. The low to middle-range grunt the kit gives is V8 like. Goes up any hill. And without the hassles, it really is bolt-on. Those that don't understand, think it makes for a racer. The increase in grunt comes across the range, and with a light foot I get a small improvement in mileage. The only two issues I've got with it, is that a leaden foot can be costly. But then it's going to be, a leafer is heavy. My other beef is the kit price, but then I'm tight.

It still works out cheaper than a Tdi or V8 swap (they only look cheap) and is far easier. With unmolested leafers at 'classic' status these days, the Tdi craze is slowing. It's already happening, blokes are taking 'em back out again. It's a very noisy conversion, so maybe better suited to weekend toys and the deaf. However, ACR kits on eBay get near what you pay for them, because those that have them don't sell 'em! Whereas a Tdi conversion makes you take a hit on the whole vehicle when on eBay, and you'll see lot os those lashed in, and selling cheap. Your price goes down, not up. A V8 is nice but you've gotta knock things about, and bulkheads aren't cheap or a strong-point. You won't see your money back on it.

The ACR kit is bolt-on / bolt-off and works. Simple. I run mine on a BLOS. I started out with just the SU carb jobby. No one conversion is perfect, but for me, especially if you can find a 5MB 2.5, as mine, factoring the overall and not just the headline-rate. Start and finish, looking at it hard, it's the way to go.

'Judging by what sells, I'd say they have it wrong. 'They' will poo-poo everything I've said, there's a hundred blokes with the usual conversions - I'm outnumbered.

I'd counter that those are the vehicles selling cheap, and the more worthwhile your vehicle, the more the point is valid. Of course, if your vehicle isn't worthwhile.... but best I declare defeat now.
im a little confused now, is your landy a diesel or petrol? My original comment was made in the belief you had a petrol engine. My comment is not so valid if we are talking about a diesel. I agree with you about TDI conversions and decreasing the value of the vehicle compared to a well set up original.

Col
 
There’s some muddling here.
. Petrol or deseasel, the point was "Turners Engineering, those fine purveyors of rebuilt series engines do not recommend 'tweeked' cam shafts.".
ACR's point was "OK, yes but why?" on the facts ACR shot Turner down, yet for reasons those that understood what ACR were saying could not fathom, the takeway for most was odd. Turner was left, 'Face down, dead in the water', and history proves it, but ACR failed to get their point across. ACR wasn't understood. The result, Turner lost the technical argument but won PR. See, there it is again, second comment in this thread.

Meantime, all and sundry went off to "The Land of the V8/Tdi" etc. Years of forums threads on how to do such things.

It was an interesting thread. The blunt truth is, and was, sitting rooted in diesel use for chissakes. This design in its petrol form, leaves the factory in such a 'cooking' state of tune, there's a massive ceiling above it. Even hopped up to the level of my lump, it's not under stress. At a max of 4400ish rpm, and there's little point going that high, it's still at 'cooking' level. This is AFTER ACR have done with it. It's massively more torquey.

In the real-world, driven at mid-range, it gives the V8 something to ponder. A leafer at much over 60 is dangerous, I wouldn't want anything faster, not in a leafer anyway. To cruise at 55mph and do any hill at 'traffic-speeds', is all I need.

If the Turner comment is correct, 1) It's been 15 odd years, the trail of bits behind all those tweaked ACR engines must be evident 2) I should run out to my wagon and hold my foot to the boards? Sustained for long enough, I have to concede, Turner will be kinda' proved correct? It will blow... eventually.

Me? We could do that with any engine. It will blow. Most of us have affinity to things mechanical. Never been anywhere near a red line with mine.

As for the Tdi fad, at about the time I plonked my ACR kit on, I first saw a Tdi jobby. I thought - founded on instant-gratification - "That'll be coming out". And the fad was the V8 came before that. At the time the proponents said it was cheap. Really? You couldn't give the old 2.25 Petrol lumps away. So many have been lost, soon they'll be like gold, and a 5MB?! I know I'm out-numbered by a huge majority... every man-jack has gone that way.

I don't think time is on their side, and judging by the current foul-ups seen on eBay, time can't be kind to all. My ACR Powerplus kit can be removed very quickly, and sold for near what I paid for it. The kit bolts on to make for a quiet, grunty leafer, working well. In reality it looks vastly pricey, but under scrutiny, starts to look the cheapest of the lot.
 

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