R

roiltide

Member
Hi everyone!

I've been working on rebuilding an old Series 3 for the past year and a bit, and it's finally at a stage where I can take it out fairly regularly. It has an original 2.25l diesel engine (5 bearing, I believe), which is (understandably) slow.

Currently, I'm topping out at about 45MPH on the flat, and ending up below 30 on hills, with downshifting. As far as I can tell this is pretty typical performance, but I would like to be able to hit 60MPH as a top speed, and maintain a better speed on hills. It's fitted with a Fairey overdrive, but can't accelerate in 4th with it engaged, you end up losing speed.

My initial thought is that the best bet would be to swap the engine out (I suspect that when new it had a bigger one, given the overdrive, which someone has at some point robbed out), but I don't want it to be much faster, just a little bit. Would going over to the 2.5 Diesel give me what I'm looking for? Is swapping to the 2.25 petrol feasible (I know they made about 10hp more originally, and can be tuned more effectively)? Alternatively do I just need to bite the bullet and go for a 200 di?

If anyone has thoughts on what the best way would be to get a small performance boost, I'd really like to hear them. I'm not trying to turn it into a fast truck, just one which is marginally less of a hazard on dual carriageways.

Thanks!

 
Something is wrong then.
Overdrive you should use as a 5th gear only and any hill will see you losing speed and have to change out of Overdrive. It's only any good on the flat or downhill. Most of the time you can't use it.
In general an Overdrive only really cuts the noise level, doesn't really give you any more speed.
60mph should be fine, had 75mph once, took a while to get there though.
That's my experience.
Try changing how you drive it and see how you get on.
Oops didn't notice you had a diesel, my experience is with petrol.
 
Thanks for your response.

I know the petrol makes more power - but if you're getting 60MPH with series diffs with the 2.25 petrol then that sounds like it might be a feasible option?
 
50 is a more enjoyable speed in my 2a petrol, 55 is do-able, can reach 60 but feels like you're giving it a kick in the nuts
 
kermit_rr said:
50 is a more enjoyable speed in my 2a petrol, 55 is do-able, can reach 60 but feels like you're giving it a kick in the nuts
Click to expand...
Thanks Kermit - and is that a 2.25 as well? What kind of speed do you drop to on longer hills?

I'm thinking that a straight swap from 2.25 diesel to petrol might be one of the better options.
 
roiltide said:
Hi everyone!

I've been working on rebuilding an old Series 3 for the past year and a bit, and it's finally at a stage where I can take it out fairly regularly. It has an original 2.25l diesel engine (5 bearing, I believe), which is (understandably) slow.

Currently, I'm topping out at about 45MPH on the flat, and ending up below 30 on hills, with downshifting. As far as I can tell this is pretty typical performance, but I would like to be able to hit 60MPH as a top speed, and maintain a better speed on hills. It's fitted with a Fairey overdrive, but can't accelerate in 4th with it engaged, you end up losing speed.

My initial thought is that the best bet would be to swap the engine out (I suspect that when new it had a bigger one, given the overdrive, which someone has at some point robbed out), but I don't want it to be much faster, just a little bit. Would going over to the 2.5 Diesel give me what I'm looking for? Is swapping to the 2.25 petrol feasible (I know they made about 10hp more originally, and can be tuned more effectively)? Alternatively do I just need to bite the bullet and go for a 200 di?

If anyone has thoughts on what the best way would be to get a small performance boost, I'd really like to hear them. I'm not trying to turn it into a fast truck, just one which is marginally less of a hazard on dual carriageways.

Thanks!
Click to expand...
Have you tried changing gear? OD is likely too tall unless on level terrain.

The engine is unlikely to have been bigger when new, as the only offering was 2.25 in petrol or diesel flavour.

The petrol 2.25 should be more than adequate in a Series and run at 55-60mph if needed, although standard gearing vs revs will limit cruising speed more than outright power.

The diesel is slower and less refined, but should still be usable.

As for engine swaps, it depends if you want a modified vehicle really. A 2.5 NaD is only 67bhp, so not a huge change in power. But there are lots and lots of potential engine swaps.

I'd say a Rover V8 still makes sense, as you can find an engine for low cost still, its a proven conversion. Will be no worse on fuel than a 2.25p but offer plenty of grunt and power and a lovely soundtrack.
 
300bhp/ton said:
Have you tried changing gear? OD is likely too tall unless on level terrain.

The engine is unlikely to have been bigger when new, as the only offering was 2.25 in petrol or diesel flavour.

The petrol 2.25 should be more than adequate in a Series and run at 55-60mph if needed, although standard gearing vs revs will limit cruising speed more than outright power.

The diesel is slower and less refined, but should still be usable.

As for engine swaps, it depends if you want a modified vehicle really. A 2.5 NaD is only 67bhp, so not a huge change in power. But there are lots and lots of potential engine swaps.

I'd say a Rover V8 still makes sense, as you can find an engine for low cost still, its a proven conversion. Will be no worse on fuel than a 2.25p but offer plenty of grunt and power and a lovely soundtrack.
Click to expand...
Thanks for your reply!

Yes I'd only ever use the OD on level terrain. When I do speed will typically ease down from 45 to 40 and then hold there, so I can go faster with the OD disengaged!

I'm okay with it being modified in principle, it had already been heavily modified when I got hold of it, but changing it for an engine which is at least period and maker adjacent would be good. The Rover V8 is absolutely a tempting proposition.
 
Yes it's a 2.25 petrol, 3 bearing if i recall. Never really had problems on normal hills, I've been fully loaded with camping and scuba gear towing a dive boat up st asaph hill on the A55
 
roiltide said:
Thanks for your reply!

Yes I'd only ever use the OD on level terrain. When I do speed will typically ease down from 45 to 40 and then hold there, so I can go faster with the OD disengaged!

I'm okay with it being modified in principle, it had already been heavily modified when I got hold of it, but changing it for an engine which is at least period and maker adjacent would be good. The Rover V8 is absolutely a tempting proposition.
Click to expand...
Rover V8 is a well precedented swap. Although in reality you can do a lot of things, you just need to read the guidance and regs for Historic and radically altered vehicles.

If you want to stick with diesel a 19j turbo diesel would be an easy swap or even a Tdi. Although the latter are more pricey to get hold of these days. The Tdi is a fantastic engine, but hugely loud and unrefined. If you aren't doing big annual milages, you may well find a petrol engine much more pleasant.
 
tottot said:
What size tires fitted ? Oversize from standard kills performance.
Click to expand...
Thanks for the input, this is a good point.

They're very tall Avon Rangemasters - I did look into replacing them with smaller tyres (I don't plan on any extreme off roading) but had very limited luck finding any smaller ones which fit on the original tubed wheels. This is another avenue I'd gladly explore to improve road performance, but I'd rather not fit aftermarket wheels if that's the only way to get smaller tyres.
 
300bhp/ton said:
Rover V8 is a well precedented swap. Although in reality you can do a lot of things, you just need to read the guidance and regs for Historic and radically altered vehicles.

If you want to stick with diesel a 19j turbo diesel would be an easy swap or even a Tdi. Although the latter are more pricey to get hold of these days. The Tdi is a fantastic engine, but hugely loud and unrefined. If you aren't doing big annual milages, you may well find a petrol engine much more pleasant.
Click to expand...
Thank you so much for the detailed advice on this. I'd personally prefer to switch to a petrol from a diesel - and from what I'm seeing here it seems like both the 2.25 and the V8 would be viable options for "small boost" so I am considering both angles (though I am also trying to figure out, again, if I can get smaller tyres). I would probably be looking to try and do it myself - if there is a particular source of truth that you have come across for V8 swaps in Series 3's, do let me know!
 
www.landyzone.co.uk

Slow diesel road test

Flat road no wind pulling away in 2nd, pity i cant put the vid on here changed from 2nd to 3rd at 25mph in about 10secs got to 40mph in 3rd in about 20 secs with a max speed in 3rd of 45mph In 4th i got 55mph in 39 secs and back to zero in about 46secs it must be running well today it went up a...
www.landyzone.co.uk www.landyzone.co.uk
I have 200di in mine now but still need to repeat the test sometime, running on rangemasters good road holding
 
Ours was a 2a petrol with 7.50 x 16 with overdrive and seemed well suited. Saying that you did need to try and anticipate the nature of the road make sure you are in the correct gear and try not to let the revs die down.
Petrol engine is pretty pleasant when running well.
 
steve2286w said:
www.landyzone.co.uk

Slow diesel road test

Flat road no wind pulling away in 2nd, pity i cant put the vid on here changed from 2nd to 3rd at 25mph in about 10secs got to 40mph in 3rd in about 20 secs with a max speed in 3rd of 45mph In 4th i got 55mph in 39 secs and back to zero in about 46secs it must be running well today it went up a...
www.landyzone.co.uk www.landyzone.co.uk
I have 200di in mine now but still need to repeat the test sometime, running on rangemasters good road holding
Click to expand...
I saw your post earlier while I was doing research before mine! Thank you so much for your contribution. How would you say the 200tdi compares to your earlier 2.25 Diesel experience?
 
Anaconda said:
Ours was a 2a petrol with 7.50 x 16 with overdrive and seemed well suited. Saying that you did need to try and anticipate the nature of the road make sure you are in the correct gear and try not to let the revs die down.
Petrol engine is pretty pleasant when running well.
Click to expand...
Thanks for this - another vote in favour of the equivalent petrol engine!
 
roiltide said:
I saw your post earlier while I was doing research before mine! Thank you so much for your contribution. How would you say the 200tdi compares to your earlier 2.25 Diesel experience?
Click to expand...
I don’t know the 200tdi personally but it’s faster accelerating for sure , I have the 200di and it’s a bit more powerful that gets me up hills where I’d be dropping down in the 2286, for me it’s an easy swap keeping original exhaust, radiator keeps the engine bay open, cleaner , drops no oil, no worries of installing intercoolers or turbo/ gearboxes/ halfshafts failing , I bought some wright off-road matting and the noise is ok listen to radio fine and gets about 30mpg

I did the Nc500 in the 2286 managed 60mph in places with OD
 
steve2286w said:
I don’t know the 200tdi personally but it’s faster accelerating for sure , I have the 200di and it’s a bit more powerful that gets me up hills where I’d be dropping down in the 2286, for me it’s an easy swap keeping original exhaust, radiator keeps the engine bay open, cleaner , drops no oil, no worries of installing intercoolers or turbo/ gearboxes/ halfshafts failing , I bought some wright off-road matting and the noise is ok listen to radio fine and gets about 30
Click to expand...
Sorry yes I meant the di, rather than tdi - a slip of the finger! That's also useful information. Sticking with diesel would mean I had to do less mucking about with the fuel system than the conversion to petrol so it's still a firm contender. Thank you again for your input, genuinely super helpful.
 
Just looking at my vid again you have the same engine I did and I got 55 quite easily, , maybe check what the issue might be , tappet gaps,engine compression, injectors, pump timing , wheels binding , throttle cable not fully opening , butterfly valve in inlet manifold , clogged air filter a few things to look at
 
Last edited:
You must log in or register to reply here.

Similar threads

R
Overdrive very stiff?
Replies
4
Views
682
Wildefalcon
W
Guldner
My Series 3
Replies
3
Views
738
Wildefalcon
W
W
Overdrive wanted for LT77 in Land Rover 127
Replies
4
Views
511
WelshWayne
W
W
2.25 diesel performance
Replies
7
Views
2K
Bobsticle
Bobsticle
S
Series 3 Loud knocking sound from the engine when running.
Replies
12
Views
1K
steve2286w
steve2286w