The Triumph Dolomite Club - Discussion Forum

While I agree things can be improved on older cars, and new ones are made to much tighter tolerances/generally more accurate, your power figures for the moderns are rather misleading. The quoted numbers for the moderns are for mainly cars with turbochargers. On the other hand, the non-turbo new fiestas are 1.1 and make under 80bhp.....
Yes, there are some screamers out there, honda s2000 will make 250bhp, but that is not a typical engine!

Most 2 litre NA engines are around 150-180ish bhp. But are easily tuned to over 200bhp with a bundle of cash.

And I think the little ford ecoboost has a life expectancy of 120k. I don't think that is too bad, comparable to most triumph engines. And most people who do big mileages probably won't be looking for that little engine anyway. (friend just picked up a BMW 330E, had to be hybrid so his company will pay him, 250bhp, great car, bags of torque but only 41mpg average, nothing like the quoted)

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Clive Senior
Brighton

On the subject of cams - Robsport are not aware of anyone currently supplying anything other than the standard profile for 1850/tr7 applications, I've had no response from the usual suspects, so it looks like the only viable option if you want a hotter cam is to find somebody willing to re-grind as per Henk's recommendation.

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Specifications for those cam references listed on the third page I posted from the Triumphtune book must exist somewhere...apologies the image is on it's side, it's a quirk of some images posted from iphone

I think Kent used to supply Cox & Buckles/Moss back in the days when Triumphtune was still an entity...

I agree with that, I suspect the big boosts in power have come from turbo charging and electronic fuel injection.

Through EVs are making all that obsolete. I saw an M5 get absolutely destroyed by a Tesla at a set of lights. The M5 driver was creeping up to the lights and revving before they changed, absolutely desperate to beat the Tesla into the lane merge. When they went green it wasn't even close, the Telsa was at the merge a couple of car lengths before the BMW.

OK, i'll hold my hands up, I may have exaggerated for effect a bit! But all the recent crop of "hot hatches", mostly turbo'd I admit, have outputs around the 250bhhp range, which is pretty much an industry standard since Saab's research proved that 250 horses is as much as anyone can usefully use in a FWD car. (Which they all are nowadays)

I'll also admit that you CAN get 250bhp from a Sprint engine, if you are willing to cherry pick every component and spend an inordinate amount of time and money. Even then, it's not likely to be as reliable as those modern hot hatches in the long run, even if it never sees a track. Though I can't think of a single Sprint with that much power that ISN'T a pure race car. Road going Sprints tend to top out around 180bhp. Probably because the cost of those extra 70 horses is too high for most to pay.

Even my "cooking" and definitely NOT sporty 2006 Citroen Xsara Picasso chucks out 147bhp from it's NA 16v 2.0 (Mi16 derived) petrol engine. I'm perfectly sure that a remap, adjustable fuel reg and maybe some slightly bigger injectors would push that close to 200 horses without breaking the bank. It works on the almost identically engineered Vauxhall redtop. I'm not going to try it as it's basically SWMBO's car and is automatic trans, it has "sufficient" power as it is and I don't want to lose bottom end torque in favour of top end power i'll never use!

Perhaps the point I was trying to make is that, in the 70s, the Sprint was pushing the boundaries of what was possible, to get 127bhp, don't forget, the Sprint was going to be called the "Dolomite 135" till they found they couldn't guarantee the extra 8 bhp! Whereas nowadays, they may be building the cars with only an extra 30-50 horses, but the potential is there to go much higher without sacrificing reliability.

Truthfully, even a speed freak like me doesn't really NEED 250 bhp to be happy, the Carledo survives on a mere 140 by judicious weight saving and is still a ton of fun! Which is probably why manufacturers are going for relatively smaller engines in bigger, heavier bodies. Joe Bloggs on the street has no wish or need to do 0-60 in 5 secs or 170mph flat out. That 80bhp 1100 Fiesta is probably aimed at new drivers with insurance costs in mind, but bear in mind that it's ancestor, the MKI Fiesta 1100 (which WASN'T the smallest engine in the range then) was only something like 50 bhp! And the CAR was probably half the weight of the modern version.

This idea is taken to the extreme by the Ford 1.0 Ecoboost and things like the Citroen C5 Safari, something over 2 tonnes and a 1.6 ltr turbo diesel under it, The Citroen you'll be lucky to get 80k out of before it's toast (helped by EGR and DPF clogging it's arteries) I doubt many ecoboosts will make 120k, I know several people who have killed them in under 50k, especially in the heavier Focus body.

There are of course, other factors, besides better production standards, EFi and mapped EI have improved performance AND economy by an enormous amount, just from making the engine more efficient. I'm just sorry that the latest improvements in IC, like "camless" engines, will never now see quantity production because of the rush to electrify everything.

Steve

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'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.

Apparently the ecoboosts are very sensitive to oil, especially as teh cambelt runs in the stuff. Wrong oil and it falls to bits. I know a Triumph chap who owns a garage, customer reluctantly took his car in and the cambelt was breaking up, bits everywhere. Cheapest option was a new engine, £1000 apparently.
When we hired a mustang in the states, we had the 5 litreV8. But in all honesty, I reckon we should have had an ecoboost. Less power (only 320 IIRC) but much better torque curve. Actually, an MX5 would have been even better (maybe bootspace for 3 weeks worth of luggage may have been tricky)

But I think Jeroens point is well made. If an engine is well put together, it will make better power. And most modern engines are indeed built to close tolerances. I wonder if my Sprint engine will be as well put together. All standard stuff, compression, cam etc. But plan to get the timing set correctly. Maybe I should clean up the inlet and exhaust ports.

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Clive Senior
Brighton

Blueprint it, everything, even the oil pump, get it all balanced, get the ports matched and the exhaust manifold matched to the downpipe. Fit a 123 programmable dizzy, a decent freeflowing exhaust and a vernier timing gear. Assemble it all carefully and it'll probably show you somewhere around 140-150 horses and be reliable and smooth running. For the icing on the cake and big improvements in power AND economy ditch the carbs and go to EFi! If you've done the right groundwork (and won the lottery by getting a sound block) it'll take the extra horsepower happily.

I would say the overwhelming majority of Sprint engines aren't giving even their rated 127bhp. Bad production tolerances, Cam timing errors from past head skims, worn distributors and carburettors all combining together to give "less than optimum" performance. It's not really THAT bad of an engine, especially when you consider that it was a "first" in many ways, never a good thing IME! But to make the most of it, you need to overcome the shortcomings the factory built in, by building it the way they SHOULD have, ie according to the blueprints, rather than the somewhat sloppy production tolerances of the time!

Steve

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'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.

It is staying carbs. And it won't get balanced either, I am a tightwad and it won't get over-revved. Dizzy I will work on, timing I will re-drill the sprocket. Simple stuff to get it as right as possible with little outlay.
Still think I should have put a saab turbo (or the griffin version) in, but that is another can of worms.

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Clive Senior
Brighton

Here you go again. Been there done that. Fitted a Kent cam when Kent did make these 20 years ago. No bottom power, useless cam. Tight corners were lower gear to pick up speed again. Fitted the HS6 ones. Correct needles setup on a dyno and still not an improvement. More hp's in the higher revs but too large for the lower revs. No use.

Take the head off, skim under an angle to have maximum compression ratio, grind the valves and seat 3 angles to have more flow and time the cam correctly and you have std sprint figures with a std cam and carbs and still a driveable car.

As steve said earlier, blueprinting is the way to go. Bolting whatever you can buy to an 1850 or a sprint, super webers etc. are not much use. Start at the engine itself. There's no such thing as bolt on instant power to a Triumph slant engine.

Be my guest to try all the bolt on goodies but the head needs a skim and the valves and seats a few hours of a machineshop worker and that's it.

Jeroen

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Classic Kabelboom Company. For all your wiring needs. http://www.classickabelboomcompany.com

I'm a fool investing as much in the engine as I did, without knowing the outcome other then "runs fine". No known power figures after the rebuilding of the engine. Maybe I should look for a dyno nearby to confirm the improvement.

It looks from all of your replies that I need to buy a spare head and work on it and put a better camshaft and carbs on my engine then.

I still reckon you are missing a trick by not balancing the engine. Yes it's money, but it's money well spent. An unbalanced engine (or even a merely badly balanced one) will fight itself. it will give less power, run less smoothly, pick up slower, wear out faster, worse fuel consumpion etc et-boring-cetera. No matter how well or carefully you put it together, it'll be no better than when it rolled off the line 40 years ago. Which might have been OK, in rare cases, might even have been decent, but was mostly pretty poor.

Now you have the chance to make it as good as it CAN be, for not an enormous outlay. It'd certainly cost less than a pair of 45DCOEs and a Mangoletsi inlet and could well deliver better power (depending on how bad it was to start with) besides the other side effects of longer life, better pickup and MPG and smoother running. To me, it's a no brainer. I can understand how you'd like to build the best engine you can for as little money as possible (don't we all?) But like a building or a paintjob, the end result is only as good as the foundations/prepwork. Fail to get THAT right and whatever you do at the top end is wasted.

Oh, and balancing works and gives valuable improvements throughout the rev range, not just at the top end! It's just that a badly balanced engine is much more likely to grenade at 7k than a well balanced one!


The Saab engine is (was) made by Saab and derives more ancestry from the Triumph slant, even in its post Y2K form than any relationship to Vauxhall. The GM buyout just gives you a handy chance to fit a Vauxhall gearbox (the Manta/Omega/Carlton box) to a Saab engine cos that's what GM did! For my money, either a Saab turbo or any of the 16v C20XE derived Vauxhall engines are a better choice than messing with a Sprint motor, it's hard to choose between the 2, both have their advantages and disadvantages. But my bias is well known, so i'll say no more about that!

Steve

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'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.

Flywheel was lightened, recesses were made just next to the mounting points where the clutch pressure plate bolts on. Then crankshaft including flywheel and clutch (LUK) were balanced: cost me about €600 back in 2015.

I went the same route, the angle in the cylinder head made skimming a challenge. When skimmed the holes for cylinder head studs need altering by memory.

That is correct. You can't just skim an 1850 type head because you will hit the valveseats before any serious amount of reducing the volume of the combustion chamber. An 1850 head you skim under an angle to have the most material taken away in the deep area and just toughing the seats. From memory I believe it's around 1:10 maximum achievable. By skimming under an angle the holes on the face don't line up with the engine deck anymore but that is solved by drilling these slightly larger. The same as skimming a sprint head to have more compression you most of the time need some drilling as when skimming the angled holes come closer. My new 1850 project is actually a 2liter with an 1850 head to have even more compression raise. Another advantage is a nice squish area by the 'smaller' head.

Jeroen

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Classic Kabelboom Company. For all your wiring needs. http://www.classickabelboomcompany.com