1500HL Tuning

[clubbyal79ch]

Are there any tips or threads regarding tuning the 1500 engines, I'd like to get 90-100bhp & a similar torque figure. I have access to a machine shop, so would like to do the work myself.
So far I'm changing the following
Air box for a ITG filter
Electronic ignition
Free flow exhaust
Some minor porting to the head

Any other ideas?

[Galileo]

Only have technical rather than practical knowledge having never owned a 1500 Triumph, but everything I've ever read suggests look at increasing torque and do not go chasing revs for it would be far cheaper to get a 1300 instead if you plan on doing that.

Reason for this is that the 1500 engine was a victim of machine shop rationalisation, the crank diameter was increased to match the 6 cylinder engines, but retained the same 3 main bearings, the steel hardening was reduced to save money (EN40 to EN16? Something like that!), so it ended up with a heavy weak crank made from inferior steel with poor wear characteristics and a long stroke. Not a good recipe for an easily tunable engine without spending a lot of money to mitigate the weaknesses.

I'm sure someone with some real world knowledge will come on and offer some solid tips, and you could do worse than search on Triumph Spitfire 1500 tuning, and for that matter, the MG midget used the same engine. Plenty of people raced with the 1500, sounds like you just need to know the limitations of the lump and factor that in, oil cooler and adding extra oilways to the crank always seem to come top of the list when it comes to reliability.

viewtopic.php?f=19&t=29763&p=283332
viewtopic.php?f=4&t=30827

[yorkshire_spam]

I have a 1500 Spitfire and plan the following for my performance engine (whilst keeping my engine with the original number relatively standard)
[*]Fast road cam from Newman cams (with appropriate followers also from Newman)
[*]Ported/flowed head
[*]Oil cooler (already fitted with standard engine - I wouldn't want to risk the alpine passes without one on a 1500 engine)
[*]Lightened and equal mass conrods and pistons
[*]duplex cam chain with vernier timing adjustment
[*]Switch from twin SU HS4 to quad mikuni bike carbs. (Custom manifold etc. required)
[*]Custom air box with remote intake to get cool air into the engine (Sticking pancakes / K&N on helps flow, but on the Spit you end up pulling warmer air)
For the Spit I also have the wide radiator to keep cooling under control.
If I had a bottomless bank account I'd be looking at a steal crank, but I simply can't afford or justify it.

[cliftyhanger]

I had a "tuned" 1500, it produced 91bhp on the rollers, the same as an 1850.

I did 5 cranks in that engine.....and it was carefully built. But the vandervell bearings that were really good are just not available.

The cheap way to get the sort of figures you are looking for are (according to folklore):
4 branch manifold (the club is getting some made, so get on the waiting list)
Toledo 1300 head. I think that gives about 10:1 CR on a 1500. Or skim the 1500 to get similar CR
TR5 profile cam (good as it is designed to work at sensible revs)

Of course additional porting will not go amiss. Get the distributer curve altered to suit or use a megajolt. Then a trip to the rollers to get the needles sorted.
Budget for a thermostatic oil cooler, and you MUST use a decent oil. Millers CSS 20/60 or something similar.

[cleverusername]

Are there any tips or threads regarding tuning the 1500 engines, I'd like to get 90-100bhp & a similar torque figure. I have access to a machine shop, so would like to do the work myself.
So far I'm changing the following
Air box for a ITG filter
Electronic ignition
Free flow exhaust
Some minor porting to the head

Any other ideas?

Are you sure you want to do this? I like the 1500 engine, the torque makes it a good fit with the Dolly, but it is not really suitable for high power outputs.

Peak power comes at 5500rpm and I wouldn't be happy revving a long stroke 3 bearing engine that hard on a consistent basis. You might end up spending allot of money to increase power high up, when you could never use it.

I am not saying it can't be done, I am not an expert and I believe posters here have tuned them successfully, but I suspect you would have to do something with the bottom end to stop it ending in tears and that could get expensive.

Also there is the diff and gearbox to consider. I don't know much power they can take.

[cleverusername]

Only have technical rather than practical knowledge having never owned a 1500 Triumph, but everything I've ever read suggests look at increasing torque and do not go chasing revs for it would be far cheaper to get a 1300 instead if you plan on doing that.

Reason for this is that the 1500 engine was a victim of machine shop rationalisation, the crank diameter was increased to match the 6 cylinder engines, but retained the same 3 main bearings, the steel hardening was reduced to save money (EN40 to EN16? Something like that!), so it ended up with a heavy weak crank made from inferior steel with poor wear characteristics and a long stroke. Not a good recipe for an easily tunable engine without spending a lot of money to mitigate the weaknesses.

I'm sure someone with some real world knowledge will come on and offer some solid tips, and you could do worse than search on Triumph Spitfire 1500 tuning, and for that matter, the MG midget used the same engine. Plenty of people raced with the 1500, sounds like you just need to know the limitations of the lump and factor that in, oil cooler and adding extra oilways to the crank always seem to come top of the list when it comes to reliability.

viewtopic.php?f=19&t=29763&p=283332
viewtopic.php?f=4&t=30827

I think the stuff about reducing the quality of the steel hardening is a myth. As far as I understand it the stroke is simply too long and the crank too heavy, on later engines, for the 3 bearing setup to cope.

[Galileo]

Fair enough, not sure where I read that either, could be Pistonheads or The Journal of Automotive Engineering (1972). I was looking at the latter most recently, they have the odd automotive book at Cambridge Uni library!

[Carledo]

I think the stuff about reducing the quality of the steel hardening is a myth. As far as I understand it the stroke is simply too long and the crank too heavy, on later engines, for the 3 bearing setup to cope.

Even without the hardening quality issue, the problem was there from the introduction of the "big crank" 1300 in the 1970> Herald 13/60 (code GK) The big end journal size was increased without attention to lubrication so the same amount of oil had to lube a larger area - and it mostly didn't! Then the 1500 came along with an increased stroke and even more weight which made everything worse still!

This is why, if you want to build a screamer, the 1300 "small crank" Spitfire engine is so highly regarded, it doesn't have the inherent flaws of the 1500 and can produce more horses for longer than any 1500 ever will. However, this motor is now getting rare (and expensive) and we work with what we have, so......

All the 1500 savvy racers say the best improvement is to cross drill the crank to get better lubrication and go from there, uprated pump, oil cooler and very good oil follow that. Lightening and balancing the rotating masses is good for pickup AND longevity, then add your choice of bolt-on goodies. My choice, a decent TR5 spec cam, ported, matched and flowed head, 4 branch and extractor exhaust and a single 45DCOE. Oh and a 123 dizzy or Megajolt. If you're REALLY brave (and richer than me) getEFi too!

Steve

[clubbyal79ch]

Brilliant responses, I love forums for this reason. A few people have said skim the head to raise the CR, if so how much would be a ball park figure, if upto 0.010" I can surface grind, if more I can get it milled and then ground to achieve a near perfect flatness
Also I'm not after a screamer, just a little more BHP and more importantly torque for those long hills when the car is laden. I've had 2 1850s in my youth and loved them both, but this car came up in the right colour and in fairly good condition.
Thanks again it makes great bedtime reading

[trackerjack]

Brilliant responses, I love forums for this reason. A few people have said skim the head to raise the CR, if so how much would be a ball park figure, if upto 0.010" I can surface grind, if more I can get it milled and then ground to achieve a near perfect flatness
Also I'm not after a screamer, just a little more BHP and more importantly torque for those long hills when the car is laden. I've had 2 1850s in my youth and loved them both, but this car came up in the right colour and in fairly good condition.
Thanks again it makes great bedtime reading

Not really a good idea to grind the head as it ends up too shiny! the grooves caused by milling help clamp the and seal the head gasket.
I have the SAH tuning book in which is what to do with this engine is not only discussed but there is an example shown. I can scan it and send it to you if you like.
I always thought that the Ford crossflow would make an excellent conversion but hey I like Fords apart from Pinto's!

[marko]

Regarding the above post, has anyone ever gone to xflow in a Dolomite? I'm working alongside a guy who builds xflow race engines and love the idea of a reliable 190bhp from a 1600.

[soe8m]

Or put a tr7 engine in it.

Jonners.

[cliftyhanger]

Or put a tr7 engine in it.

Jonners.

Which is what I did! I doubt power is much more than my tuned 1500, but it feels faster. And I have no concerns about cranks/BE etc, it just works and economy is better too.

As to a crossflow. I thought all the westfields etc used 1700 crossflows on webers, and in geeral all made approx 130bhp. I reckon if somebody is getting 190, it won't be much use in a road car and I doubt it will last 50K! As implicated, a race engine. For a modern engine, how about a 2 litre or 2.3 duratec? Light as all aluminium, and well over 200bhp achievable on std internals (maybe a mild cam swap for more) and with some effort rather more.... and will last well and be very tractable with a very fat torque curve.

[clubbyal79ch]

trackerjack

I have the SAH tuning book in which is what to do with this engine is not only discussed but there is an example shown. I can scan it and send it to you if you like.

If you could scan it that would be great.

Thanks again this make very good reading. I'm not after lots of horses, just a bit extra to make it more drivable when fully loaded.