Getting something out of a 1500 lump in the midget
Discussion
I know these Triumph 1500's have a shocking reputation, but I have a midget sat there doing nothing as its currently a tired ole donkey that needs a rebuild. Can't sell it due to family ties and all that.
If its going to get worked on, it needs some improvements.
Anyone suggest anything to read or someone to speak with that gets these motors working a little better.
I'm thinking about using the car on the odd classic road rally, so it doesn't want or need to be a screaming race engine. just upping the mid range and giving it a bit of 'fizz'.
I had considered a K series and T9 conversion....but then its all but useless as far as classic rallies are concerned.
anyone?
thanks
JP
If its going to get worked on, it needs some improvements.
Anyone suggest anything to read or someone to speak with that gets these motors working a little better.
I'm thinking about using the car on the odd classic road rally, so it doesn't want or need to be a screaming race engine. just upping the mid range and giving it a bit of 'fizz'.
I had considered a K series and T9 conversion....but then its all but useless as far as classic rallies are concerned.
anyone?
thanks
JP
A (vaguely) sensible route would be to megasquirt it - that is fit an aftermarket injection kit. You use a single carb US manifold and use the old carb as a throttle body add a single (or if you feel ambitious 4) injectors, a MAF sensor, and temp sensor, swirl pot, fuel pump and a few other odds and sods and you suddenly get loads more torque and some more power. In fact so much that you can snap driveshafts! Most of the bits can be got from a scrappy. Mates of mine have megasquited their Westfield and a 4 pot Lotus Esprit both of which went indecently fast!
More info here
Megasquirt website.
There was a guy who did this to a 1500 midget which was in Practical performace car, but the article does not seem to be on the web any more.
HTH!
Regards
Spunagain
More info here
Megasquirt website.
There was a guy who did this to a 1500 midget which was in Practical performace car, but the article does not seem to be on the web any more.
HTH!
Regards
Spunagain
Guy here went the Megasquirt route and has a good lot of info on how to do it. Also has a supercharging guide on his site.
http://82.44.126.36:76/Inject.htm
http://82.44.126.36:76/Inject.htm
You're right in that the engine is a bit of a donkey! Nothing fantastic you can do short of the drastic stuff above, apart from engine changes.
You could probably get about another 10% extra by having the head breathed on, bigger SU carbs properly set up, a fast road camshaft and a better manifold / extractor exhaust system. After that, it gets pricey - lightening and balancing. Supercharging is an option (period accessory) but that's a fair increase in torque for the gearbox to have to deal with too.
Have you tried asking the triumph lot? I know the 1300 tunes up better and revs more sweetly, but not much more than that....
You could probably get about another 10% extra by having the head breathed on, bigger SU carbs properly set up, a fast road camshaft and a better manifold / extractor exhaust system. After that, it gets pricey - lightening and balancing. Supercharging is an option (period accessory) but that's a fair increase in torque for the gearbox to have to deal with too.
Have you tried asking the triumph lot? I know the 1300 tunes up better and revs more sweetly, but not much more than that....
Bob T whose DIY injected 1500 was enjoyed by PPC has a website on which he showed how he did it maybe a Google search ....
YES here it is
http://82.44.126.36:76/Inject.htm
Dont dismiss the Trump engine completely, we have in the Midget And Sprite Club a Tifosi Rana (Fi-glass Sprite) that runs a screamer of a tuned 1300 Spitfire engine.
And there are folks who have put the K series and the Zetecs in Midgets too
Marvellous machines
edited to add, At Marham on a couple of their charity track days Bob's 1500 simply left my nicely quick road midget 1293, for dead
I nearly got out to see if a wheel had fallen off
I was at the ton. Bob was significantly better and accelerating...
I was dead jealous
YES here it is
http://82.44.126.36:76/Inject.htm
Dont dismiss the Trump engine completely, we have in the Midget And Sprite Club a Tifosi Rana (Fi-glass Sprite) that runs a screamer of a tuned 1300 Spitfire engine.
And there are folks who have put the K series and the Zetecs in Midgets too
Marvellous machines
edited to add, At Marham on a couple of their charity track days Bob's 1500 simply left my nicely quick road midget 1293, for dead
I nearly got out to see if a wheel had fallen off
I was at the ton. Bob was significantly better and accelerating...
I was dead jealous
Edited by perdu on Friday 12th February 23:59
I have a 1500 in the throws of bring rebuilt for sprinting/hilclimbing. BNWChris on here has one that he already does that with. See the thread on overboring in Cassic Cars and Yesterdays Heros section...
The 1500 is an engine unfairy maligned by people who don't understand it usually. Its weakness (in teh midget) is gtting its oil too hot on long motorwy journeys and the big end bearings suffer. You NEED an oil fiter. Mine has one and when i dismantled the engine so it could be properly sorted, the bearings appeared to be in rude health, after 60k and regular oil changes so that proved eh worth of the cooler, as opposed to the state of it before it was fitted. It's not the best engine in the world, but its not the worst either.
the Torque from the 1500 is its best feature though as you will have discovered, especialy if your primarily using it on the public roads. Before rebuilding mine, all it had was k&N filter manifold and free flow exhaust plus richer needles of course. It realy made a noticable improvement all round.
Best thing i did though was lower it by 1" 3/4" ARB poly bushes all round(escept nylatron arb bushes) 400lb front srings (standard rears) , braided hoses and a rear cage. The stiffness and reduced roll transformed it. (not so great on a bad road surface but I can live with that).
The 1500 is an engine unfairy maligned by people who don't understand it usually. Its weakness (in teh midget) is gtting its oil too hot on long motorwy journeys and the big end bearings suffer. You NEED an oil fiter. Mine has one and when i dismantled the engine so it could be properly sorted, the bearings appeared to be in rude health, after 60k and regular oil changes so that proved eh worth of the cooler, as opposed to the state of it before it was fitted. It's not the best engine in the world, but its not the worst either.
the Torque from the 1500 is its best feature though as you will have discovered, especialy if your primarily using it on the public roads. Before rebuilding mine, all it had was k&N filter manifold and free flow exhaust plus richer needles of course. It realy made a noticable improvement all round.
Best thing i did though was lower it by 1" 3/4" ARB poly bushes all round(escept nylatron arb bushes) 400lb front srings (standard rears) , braided hoses and a rear cage. The stiffness and reduced roll transformed it. (not so great on a bad road surface but I can live with that).
Edited by neilr on Wednesday 17th February 13:30
thanks for that.
the weak link the motor seems to be the crank. as everything else you mention is curable.
The crank obviously limits revs, but as I want torque, less of an issue. its finding the sensible limits of tuning that will be the fun part. I've read up a load more recently and there are things to be done to improve the internal oiling and the control of the crank flex to a degree.
Have you increased the braking performance?
JP
the weak link the motor seems to be the crank. as everything else you mention is curable.
The crank obviously limits revs, but as I want torque, less of an issue. its finding the sensible limits of tuning that will be the fun part. I've read up a load more recently and there are things to be done to improve the internal oiling and the control of the crank flex to a degree.
Have you increased the braking performance?
JP
I'm sure Neil means you NEED an oil COOLER (already got a filter )
On the MGE BBS recently there has been much discussion, by people who obtain serious power from 1500s, about the proper place to tap oil supply from to improve oiling, for rocker shaft lubrication and the like
It would be worth your while to follow up the recent threads in there if you are looking for decent improvements
http://tinyurl.com/ye9k43z
is one such thread that will help you and if you join in with the BBS you can access millions of miles (I may not be exaggerating...) of relevant information and for MG Austin Healey based questions it may be one of the prime advice sites around.
Joining is free and they will make you very welcome
HTH
Bill
)On the MGE BBS recently there has been much discussion, by people who obtain serious power from 1500s, about the proper place to tap oil supply from to improve oiling, for rocker shaft lubrication and the like
It would be worth your while to follow up the recent threads in there if you are looking for decent improvements
http://tinyurl.com/ye9k43z
is one such thread that will help you and if you join in with the BBS you can access millions of miles (I may not be exaggerating...) of relevant information and for MG Austin Healey based questions it may be one of the prime advice sites around.
Joining is free and they will make you very welcome
HTH
Bill
Sorry, yes an oil COOLER! All the suspension mods, rear cage and the braided brake hoses were done before taking the engine out and messing with it. I'm progressing along to getting it back together so I'll report back on how it goes when the engine is back in. Only mods to brakes were braided hoses. I use Mintex 1144 pads which i find very good. With the engine mods it may well require a larger disc/caliper setup but ill see how it goes when the engine is back in.
Speaking of the crank I have had it balanced and tuftrided. I figured with sprint/hillclimbing its not like your at WOT for extended periods of time as per circuit racing so should be ok.
neil
alfa pint said:
You could probably get about another 10% extra by having the head breathed on, bigger SU carbs properly set up, a fast road camshaft and a better manifold / extractor exhaust system. After that, it gets pricey - lightening and balancing.
You can get way more than 10% over stock on the 1500 and you certainly do NOT need bigger SUs (all you will do is drop the intake charge velocity and reduce power). You definitely need a better exhaust mani - the stock Midget one is appalling and one of the reasons the car produces less power than the equivalent Spitfire 1500.My fast road 1500's regularly produce between 100 - 110bhp and 90-95ft.lbs on what is a relatively mild cam.
What you CAN'T do with a 1500 is use a cam profile that requires uber revs (unlike the early 1300s) because the bottom end just will not survive.
Have a look at:
http://www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgb...
Regards.
Ginetta G15 Girl said:
alfa pint said:
You could probably get about another 10% extra by having the head breathed on, bigger SU carbs properly set up, a fast road camshaft and a better manifold / extractor exhaust system. After that, it gets pricey - lightening and balancing.
You can get way more than 10% over stock on the 1500 and you certainly do NOT need bigger SUs (all you will do is drop the intake charge velocity and reduce power). You definitely need a better exhaust mani - the stock Midget one is appalling and one of the reasons the car produces less power than the equivalent Spitfire 1500.My fast road 1500's regularly produce between 100 - 110bhp and 90-95ft.lbs on what is a relatively mild cam.
What you CAN'T do with a 1500 is use a cam profile that requires uber revs (unlike the early 1300s) because the bottom end just will not survive.
Have a look at:
http://www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgb...
Regards.
thought this was you
sdgpm
I would trust this girl with my car's life
If I had a 1500
bill
Sorry - only just came across this.
My 1500 Midget is in a mild tune and happily goes much faster than the teeth sucking guys will expect. On a rally that includes "tests" (ie short stages) people who had seen us set SFTD on one stage (sorry - "test") on the previous rally (our first ever rally!) explained that these tests were all about power and therefore we didn't have a chance. By the end (when we'd got the hang of it) there were only 3 faster cars. A genuine and rally prepared 2.7 Carrera, a modified TR6 and a very serious looking TR4. There were a number of Mini Coopers and Mexicos behind.
My car (with idoit me driving) is also as fast or faster than MGBs in the standard class on sprints and hillclimbs (though they often have entirely standard suspension and mine is mildly modified)
However, if you want to win in rallies then a late Midget is the wrong place to start. The class system is unashamedly designed to keep Escorts and 911s way from "proper classics". A 1500 is a bit faster than a 1275 but nothing compared with the 70's cars it is rightfully classed with. A 1275 would be a better bet - slower but up against much older cars.
For some reason a Triumph expert who gives apparently excellent advice on here and has a very good reputation hasn't replied to my emails. I would have loved for her to do my rebuild but instead I've gone with a local guy for the labour and parts from Jigsaw for the rebuild. I can't recommend Mark at Jigsaw enough. Excellent service.
A 4 branch manifold, air filters, trumpets, and careful setting-up on a rolling road gives a substantial increase in both poweer and driveablilty on my car.
ps I wouldn't do anything without an oil cooler. My sister managed to break her crank on a 1500 Spitfire. Driving to school!
My 1500 Midget is in a mild tune and happily goes much faster than the teeth sucking guys will expect. On a rally that includes "tests" (ie short stages) people who had seen us set SFTD on one stage (sorry - "test") on the previous rally (our first ever rally!) explained that these tests were all about power and therefore we didn't have a chance. By the end (when we'd got the hang of it) there were only 3 faster cars. A genuine and rally prepared 2.7 Carrera, a modified TR6 and a very serious looking TR4. There were a number of Mini Coopers and Mexicos behind.
My car (with idoit me driving) is also as fast or faster than MGBs in the standard class on sprints and hillclimbs (though they often have entirely standard suspension and mine is mildly modified)
However, if you want to win in rallies then a late Midget is the wrong place to start. The class system is unashamedly designed to keep Escorts and 911s way from "proper classics". A 1500 is a bit faster than a 1275 but nothing compared with the 70's cars it is rightfully classed with. A 1275 would be a better bet - slower but up against much older cars.
For some reason a Triumph expert who gives apparently excellent advice on here and has a very good reputation hasn't replied to my emails. I would have loved for her to do my rebuild but instead I've gone with a local guy for the labour and parts from Jigsaw for the rebuild. I can't recommend Mark at Jigsaw enough. Excellent service.
A 4 branch manifold, air filters, trumpets, and careful setting-up on a rolling road gives a substantial increase in both poweer and driveablilty on my car.
ps I wouldn't do anything without an oil cooler. My sister managed to break her crank on a 1500 Spitfire. Driving to school!
Edited by BMWChris on Thursday 25th February 22:00
Edited by BMWChris on Thursday 25th February 22:17
jp-speed-triple said:
I know these Triumph 1500's have a shocking reputation, but I have a midget sat there doing nothing as its currently a tired ole donkey that needs a rebuild. Can't sell it due to family ties and all that.
If its going to get worked on, it needs some improvements.
Anyone suggest anything to read or someone to speak with that gets these motors working a little better.
I'm thinking about using the car on the odd classic road rally, so it doesn't want or need to be a screaming race engine. just upping the mid range and giving it a bit of 'fizz'.
I had considered a K series and T9 conversion....but then its all but useless as far as classic rallies are concerned.
anyone?
thanks
JP
Sorry. Haven't read all the post. But if you plan to do classic road rallies you need to check what the regs will allow. Even "sensible" mods may be against the regs.If its going to get worked on, it needs some improvements.
Anyone suggest anything to read or someone to speak with that gets these motors working a little better.
I'm thinking about using the car on the odd classic road rally, so it doesn't want or need to be a screaming race engine. just upping the mid range and giving it a bit of 'fizz'.
I had considered a K series and T9 conversion....but then its all but useless as far as classic rallies are concerned.
anyone?
thanks
JP
Sorry for jumping in on this late I race with a triumph 1500 engine, so thought I'd share a few ideas.
In the other thread you started about this you mention period mods only, so that's megasquirt etc. out of the picture.
The main problem with this block, as others have pointed out, is the bottom end. Essentially, it's just a longer throw crank version of the late (not mkiii) 1300. This engine has larger bearing journals than the mkiii 1300 and combined with the longer throw of the crank it means that the bearing surfaces are moving much faster in relation to each other for the same rpm.
The other problem is that the oil 'hole' on the crank is at the bottom of the throw, so at high revs the centrifugal (centripetal) whatever.. the spinny force is just throwing the oil back down into the sump instead of it staying in and around the bearings for a while. Meaning that although you may have good oil pressure in the block (as indicated on the gauge) you'll have about 0 psi where it counts - in the bearings.
For racing I and others have cross drilled the crank and blocked off the feed hole at the bottom. It's probably a bit drastic for what you want to do but it makes for a reliable engine and I have no worries using mine up to 7-8k. It still won't rev as freely as a mkiii 1300 due to the larger bearing surfaces and a couple of other things but so far this approach has been reliable. It will also make up for it's lack of high revs in torque, for a bit of rallying or whatever I'd reckon this will be more important to you anyway.
As oiling the bottom end is the most likely cause of failure in these engines I would suggest that you baffle the sump to prevent surge under braking/cornering. This should be an easy job, you won't need anything complex and it'll help greatly. An oil cooler won't do any harm either, it'll allow you to have more oil in the system, for road/rally use I'd fit one with the thermostat so you don't end up over-cooling the oil.
As a very first step, just make sure everything is perfectly set up as per the manual. Valve clearances, points gap/timing, carbs balance/mix etc. This stuff will change as you modify things but it's important to know where you're starting from - you never know, a good tune up might be enough..
I'd consider replacing the points/coil with either an optronic or magnetronic ignition system, this will stop you needing to fiddle with the points firstly but make the timing a bit more predictable. It's not going to give you loads more power but it will prevent 'points scatter' at high revs and should make things run a bit smoother. Get rid of the vacuum advance stuff, read up about tinkering with the advance curve on the dizzy.. but don't do it yet.
Make sure you have the 1.5" SU carbs and not the 1.25 ones as fitted to the smaller engine. Replace the air filters (perhaps with something funky like K&N, but just decent new stock ones should make a difference). Have the engine breathe into a catch tank rather than the inlet manifold. Have a look at the carb butterflies, do they have those big fat 'run on valve' spring things in them? If so replace for a set that don't.
Consider changing the exhaust and manifold to help with the breathing. If you're still not happy after all that, I'd then look at fitting a different cam, probably in your case a fast road one would suffice, the 'extreme' racing cams would render the car a dog to drive on the road.
Somewhere around here I'd take the car to a rolling road, preferably one with experience with SU carbs, and get them to set up the timing, carb needles & springs etc. You can do it yourself with trial and error, but for about a hundred quid a decent rolling road will save you weeks of mucking about. I'd recommend Pete Baldwin at Wilshire garages if he's still about - if not, try phoning one of the triumph shops that deal with racing cars and ask them who they'd recommend. It's a bit of a specialised field and many rolling road places these days just don't have the experience with the old stuff as these days it's all about printing off power curves for Fiat Puntos with wings.
Ask the rolling road operator about tinkering with the advance curve on the dizzy (you didn't already do this, right?) if you need to, here is the place to do it.
Um, after that there's no limits really. You can have the head 'breathed on' as someone mentioned, skim it a bit to up the compression ratio, lighten the flywheel, fit roller rockers, play with diff/gear ratios, investigate forged pistons and steel rods, fit bigger valves etc...
To be honest though, it's not a bad little engine (apart from the bottom end thing). Even a fairly standard one, if set up correctly should be reasonably torquey and nippy. In order to get any fun out of this project at all I'd look at reliability first then work up to screaming mods
Good luck with it! If you have any specific questions feel free to pm/email/ask and I'll do my best to help if I can.
Richy
I race with a triumph 1500 engine, so thought I'd share a few ideas.In the other thread you started about this you mention period mods only, so that's megasquirt etc. out of the picture.
The main problem with this block, as others have pointed out, is the bottom end. Essentially, it's just a longer throw crank version of the late (not mkiii) 1300. This engine has larger bearing journals than the mkiii 1300 and combined with the longer throw of the crank it means that the bearing surfaces are moving much faster in relation to each other for the same rpm.
The other problem is that the oil 'hole' on the crank is at the bottom of the throw, so at high revs the centrifugal (centripetal) whatever.. the spinny force is just throwing the oil back down into the sump instead of it staying in and around the bearings for a while. Meaning that although you may have good oil pressure in the block (as indicated on the gauge) you'll have about 0 psi where it counts - in the bearings.
For racing I and others have cross drilled the crank and blocked off the feed hole at the bottom. It's probably a bit drastic for what you want to do but it makes for a reliable engine and I have no worries using mine up to 7-8k. It still won't rev as freely as a mkiii 1300 due to the larger bearing surfaces and a couple of other things but so far this approach has been reliable. It will also make up for it's lack of high revs in torque, for a bit of rallying or whatever I'd reckon this will be more important to you anyway.
As oiling the bottom end is the most likely cause of failure in these engines I would suggest that you baffle the sump to prevent surge under braking/cornering. This should be an easy job, you won't need anything complex and it'll help greatly. An oil cooler won't do any harm either, it'll allow you to have more oil in the system, for road/rally use I'd fit one with the thermostat so you don't end up over-cooling the oil.
As a very first step, just make sure everything is perfectly set up as per the manual. Valve clearances, points gap/timing, carbs balance/mix etc. This stuff will change as you modify things but it's important to know where you're starting from - you never know, a good tune up might be enough..
I'd consider replacing the points/coil with either an optronic or magnetronic ignition system, this will stop you needing to fiddle with the points firstly but make the timing a bit more predictable. It's not going to give you loads more power but it will prevent 'points scatter' at high revs and should make things run a bit smoother. Get rid of the vacuum advance stuff, read up about tinkering with the advance curve on the dizzy.. but don't do it yet.
Make sure you have the 1.5" SU carbs and not the 1.25 ones as fitted to the smaller engine. Replace the air filters (perhaps with something funky like K&N, but just decent new stock ones should make a difference). Have the engine breathe into a catch tank rather than the inlet manifold. Have a look at the carb butterflies, do they have those big fat 'run on valve' spring things in them? If so replace for a set that don't.
Consider changing the exhaust and manifold to help with the breathing. If you're still not happy after all that, I'd then look at fitting a different cam, probably in your case a fast road one would suffice, the 'extreme' racing cams would render the car a dog to drive on the road.
Somewhere around here I'd take the car to a rolling road, preferably one with experience with SU carbs, and get them to set up the timing, carb needles & springs etc. You can do it yourself with trial and error, but for about a hundred quid a decent rolling road will save you weeks of mucking about. I'd recommend Pete Baldwin at Wilshire garages if he's still about - if not, try phoning one of the triumph shops that deal with racing cars and ask them who they'd recommend. It's a bit of a specialised field and many rolling road places these days just don't have the experience with the old stuff as these days it's all about printing off power curves for Fiat Puntos with wings.
Ask the rolling road operator about tinkering with the advance curve on the dizzy (you didn't already do this, right?) if you need to, here is the place to do it.
Um, after that there's no limits really. You can have the head 'breathed on' as someone mentioned, skim it a bit to up the compression ratio, lighten the flywheel, fit roller rockers, play with diff/gear ratios, investigate forged pistons and steel rods, fit bigger valves etc...
To be honest though, it's not a bad little engine (apart from the bottom end thing). Even a fairly standard one, if set up correctly should be reasonably torquey and nippy. In order to get any fun out of this project at all I'd look at reliability first then work up to screaming mods
Good luck with it! If you have any specific questions feel free to pm/email/ask and I'll do my best to help if I can.
Richy
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