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Maregratia

Horse power

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scan0002.jpg

 

First time to attempt to attach a photo on here so hope this has worked.

 

The car is a 150 PI CP Engine.

 

A few months ago i fitted a stage 11 unleaded Head, mild road 272 cam from TR Enterprise and a stainless Phoenix 6-3-1 manifold. New rings and Thrust washers.

All injector system reconditioned and pertronix electronic ignition.

 

Since then there has been a slight misfire around 3500rpm so decided to take the car to a rolling road garage, The mechanic soon sorted the misfire out by advancing the ignition timing to 20 deg and advancing to 34 deg at 3000rpm.

 

However i am pretty disappointed with th HP figures. I tested the compression last night all came out at 175 psi dry. Has not needed topping up with oil since running in oil was changed 1500 miles ago.

 

Car now pulls well and very quick. At a bit of a loss why the hp seems so lo.

 

 

John TR6 CUE 836J

Edited by Maregratia

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your readings are pretty similar to mine.i wouldnt take too much notice of hp figures

its the torque figures that matter on a road car,and yours are good at 150ft ib.

i am glad youve posted your results.there must be lots of other people on here,

who have had there car on a rolling road.but not put the results up, good or bad

it would be nice to compare other cars readings.but i think they will be all be similar.

dont forget the 150 bhp for early cars was a load of bull.

and if you have 125 cr car they are spot on.

richard

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Hi John

 

i got 82 BHP at the wheels with 151 lbft torque so as in the other thread about Malvern i am treating this as Zero and will see what happens when i do the mods

 

the Power is calculated from the torque so that the figure to go for, what was it at the wheels i see it is corrected

 

some people say on the 125model you need to get teh bottom engine balanced and the flywheel lightened to get the best out of things

 

i am going to get this done with a new cam, manifold and head ported etc like you so it will be interesting to see what happens

 

You already have a 150 model so i guess the improvement will be less

 

i am new to this stuff so it will be interesting to see what the Guru's say

 

i am sure Neil and Alex will input, i hope mine works

 

regards

 

david

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.i wouldnt take too much notice of hp figures

its the torque figures that matter on a road car,and yours are good at 150ft ib.

richard

Hallo hallo, listen carefully, I will say this only once :

May I state that if the power is bad, the torque is bad too 'per definition', because torque is about power x 1.36 when using

lb.ft and hp. The misunderstanding is that one can give away power at some high rpm to gain some torque at ANOTHER lower, more useful rpm. But at a given rpm, speaking in terms of torque is identical as speaking in terms of power. Both are the same AT A GIVEN RPM. When you know the power at a given rpm, the torque figure can be derived, and this can only be one torque value.

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The torque figure quoted for the TR5 was 165 lb-ft and for the TR250 it was 151 lb-ft. The higher HP value for the 5 is owed to the far better breathablity from the cam, c/r and 6-throttle P.I., preserving the torque curve well beyond the 250's 3000 rpm peak ( and precipitous drop beyond ).

 

The 1/4 mile and 0-60 mph times may serve as a good check - they are 16.8 sec/ 82 mph and 8.2 sec respectively, per AUTOCAR tests of the day. Note that they would have been provided a carefully vetted example ( Kas Kastner had a hand in some of these ) so factor that in too <_<

 

Racetorations say 130 BHP is the most they've seen in a bone stock P.I. With gas flowed head and extractor exhaust 150 BHP should be attainable - at least with Webers it is ;) giving 16.2 sec/ 86 mph in the 1/4 with an amateur driver ( me ).

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Hallo hallo, listen carefully, I will say this only once :

May I state that if the power is bad, the torque is bad too 'per definition', because torque is about power x 1.36 when using

lb.ft and hp. The misunderstanding is that one can give away power at some high rpm to gain some torque at ANOTHER lower, more useful rpm. But at a given rpm, speaking in terms of torque is identical as speaking in terms of power. Both are the same AT A GIVEN RPM. When you know the power at a given rpm, the torque figure can be derived, and this can only be one torque value.

 

 

all well and good.but if they had cooked the cp- hp figures they will have cooked the torque figures too.

 

what we need is lots of rolling road data/graphs to compare different specs of cars.

there must be lots of people who have them, but are reluctant for whatever reason to share them.

then if you wanted to improve your car you could actually see what parts will achive ,whot performance.

so come on post your rolling road results and your car spec.

richard

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Richard : I wrote something wrong : "... the misunderstanding is that someone can give away some power at high rpm to gain some torque at ANOTHER more more useful rpm..."

 

This should read : "...the misunderstanding is coming from the correct idea that one can give away some power at high rpm to gain some torque at ANOTHER more useful, lower rpm.." But at a given rpm, you can't give away power to gain more torque ( because power = torque x rpm ).

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Hi all,

 

Just thought I would add my bit.....I took mine (TR6 1976) to a rolling road tuning place (sanspeed in bexleyheath)

 

Guy was very enthusiastic about seeing an old TR, he gave me the print out and tried to explain but it all sounded a bit over my head as he spoke in kilowatts this and torque that over P etc etc....and I fell asleep....lol....

 

Anyway I think he saw the glazed look in my eyes and said the bottom line is you have about 147BHP at the wheels. so he wrote that in on the graph.

 

The engine is a stage 2 from Jigsaw racing and the tuning guy commented on what a good engine he thought it was.....

 

Bottom line for me is the huge grin on my face when driving away.

 

I have tried taking some pics of the graph and added them here, but only have a web cam and not very good quality guys...sorry

tr6_graph.bmp

tr6_graph2.bmp

tr6_graph.bmp

tr6_graph2.bmp

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Is this a CP car? This is only about 17 more HP at the rear wheels than a late USA car, and 19 more at the crankshaft, give or take. I just don't see how the UK cars can run that much better on 17 HP. I think it would take more than that to make the car come alive. However results do vary depending on the dyno, I guess. I have ordered the CP injection for my car, and I hope to do better, or I will have the head worked on. I would like to see more dyno results, however, as I have said before, I think MI 5 has them under lock and key.

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Is this a CP car? This is only about 17 more HP at the rear wheels than a late USA car, and 19 more at the crankshaft, give or take. I just don't see how the UK cars can run that much better on 17 HP. I think it would take more than that to make the car come alive. However results do vary depending on the dyno, I guess. I have ordered the CP injection for my car, and I hope to do better, or I will have the head worked on. I would like to see more dyno results, however, as I have said before, I think MI 5 has them under lock and key.

Did a late USA USA TR6 did have 130 Hp at the wheels?

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Did a late USA USA TR6 did have 130 Hp at the wheels?

:lol: I dont think so! Especially not a late detoxed one. :(

Stuart

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:lol: I dont think so! Especially not a late detoxed one. :(

Stuart

 

Think closer to 70HP at the wheels and 100ft/lbs torque. The poor thing cant get out of its own way.

 

Stan

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:lol: I dont think so! Especially not a late detoxed one. :(

Stuart

 

 

I'm not sure what was advertised here in 1976, but we have anecdotal evidence from actual rolling road test of maybe 80bhp at the wheels. This seems reasonable considering all of the emmissions **** that was choking the engines by the end of production.

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Think closer to 70HP at the wheels and 100ft/lbs torque. The poor thing cant get out of its own way.

 

Stan

There are several Dyno tests online showing about 88 at the rear wheels on a stock TR6. Corrected, this would be about the advertised HP at the crank. I will find one, or two and post the link. Here is one, there are more, and they are all very close. www.hottr6.com/triumph/tr6dyno.html

Edited by TR6 Poor

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Guest ntc
Hi all,

 

Just thought I would add my bit.....I took mine (TR6 1976) to a rolling road tuning place (sanspeed in bexleyheath)

 

Guy was very enthusiastic about seeing an old TR, he gave me the print out and tried to explain but it all sounded a bit over my head as he spoke in kilowatts this and torque that over P etc etc....and I fell asleep....lol....

 

Anyway I think he saw the glazed look in my eyes and said the bottom line is you have about 147BHP at the wheels. so he wrote that in on the graph.

 

The engine is a stage 2 from Jigsaw racing and the tuning guy commented on what a good engine he thought it was.....

 

Bottom line for me is the huge grin on my face when driving away.

 

I have tried taking some pics of the graph and added them here, but only have a web cam and not very good quality guys...sorry

 

Sounds like they may have used the same rr as you?

Both cars are fitted with JIGSAW Stage 2plus, super doper, engines. Both units being fitted with competition valves and our own billet flywheel. Robs engine is also running our design forged pistons. With the engines producing 210 & 185bhp, at the wheels, respectively. Both cars are running Lucas mapped fuel injection systems, and our own mapped distributors which follow the advance curve of the camshaft for optimum performance

Edited by ntc

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Is this a CP car? This is only about 17 more HP at the rear wheels than a late USA car, and 19 more at the crankshaft, give or take. I just don't see how the UK cars can run that much better on 17 HP. I think it would take more than that to make the car come alive. However results do vary depending on the dyno, I guess. I have ordered the CP injection for my car, and I hope to do better, or I will have the head worked on. I would like to see more dyno results, however, as I have said before, I think MI 5 has them under lock and key.

 

 

TR6 poor, I dont think you will be happy bolting on the cp injection without attending to the other things necessary like skimming the head to increase the compression, recurving the dizzy and of course the hotter cam that the CP cars were built with.

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Sounds like they use the same rr as you?

Both cars are fitted with JIGSAW Stage 2plus, super doper, engines. Both units being fitted with competition valves and our own billet flywheel. Robs engine is also running our design forged pistons. With the engines producing 210 & 185bhp, at the wheels, respectively. Both cars are running Lucas mapped fuel injection systems, and our own mapped distributors which follow the advance curve of the camshaft for optimum performance

Hello Neil can you PM me and tell me who "our" is? I may be in need of parts. I would like to know about whose camshaft blank you are using, and who is grinding it for you. And, possibly a better flowing head. Also, whose exhaust are you running. It seems the 6-3-1, with a 2.5 inch. single pipe is best for torque, your thoughts? I would also be interested in the best curve for a CP car. I'd be happy with 130 at the rear wheels. Thanks, Gene

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TR6 poor, I dont think you will be happy bolting on the cp injection without attending to the other things necessary like skimming the head to increase the compression, recurving the dizzy and of course the hotter cam that the CP cars were built with.

Well, I already have the compression, the CP cam, TR5 dist. curve, however, I am running the ZS carbs. That said, I have the mixture in the ballpark for the carbs, as I have an AF meter to set it. So, next thing is PI or Webers. Now, the CP cam was I believe designed for PI, by Lucas no less, and I got a good deal on the PI set up, CP that is, so I figure I'd give it a go. The key was what I paid for the entire set up, minus the Lucas pump. Comments? Cheers

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Perhaps I am reading this Rolling Road test wrong, but the most I see at the rear wheels is 105.7. Am I reading it wrong?

 

Run 1 is in black, Run 2 (I prsume after adjustments) is in red, with the numeric results listed underneath.

127bhp at engine, after correction for estimated power loss in transmission.

 

Doesn't sound very good for a "150bhp CP engine", but makes me feel better - 125 at wheels, from a saloon 2500 engine: self-flowed head, 10.5:1 CR, CP cam, CR thottle bodies, 6-3-1 manifold and Pi. Operator estimated 140 at engine, as the excess camber on the wheels meant that the apprentice and I had to ride the back of the car to make the tyres stick to the roller!

John

Edited by john.r.davies

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Run 1 is in black, Run 2 (I prsume after adjustments) is in red, with the numeric results listed underneath.

127bhp at engine, after correction for estimated power loss in transmission.

 

Doesn't sound very good for a "150bhp CP engine", but makes me feel better - 125 at wheels, from a saloon 2500 engine: self-flowed head, 10.5:1 CR, CP cam, CR thottle bodies, 6-3-1 manifold and Pi. Operator estimated 140 at engine, as the excess camber on the wheels meant that the apprentice and I had to ride the back of the car to make the tyres stick to the roller!

John

Now we are talking, that looks like where I want to be. Congradulations! Cheers

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Guest ntc
Run 1 is in black, Run 2 (I prsume after adjustments) is in red, with the numeric results listed underneath.

127bhp at engine, after correction for estimated power loss in transmission.

 

Doesn't sound very good for a "150bhp CP engine", but makes me feel better - 125 at wheels, from a saloon 2500 engine: self-flowed head, 10.5:1 CR, CP cam, CR thottle bodies, 6-3-1 manifold and Pi. Operator estimated 140 at engine, as the excess camber on the wheels meant that the apprentice and I had to ride the back of the car to make the tyres stick to the roller!

John

 

At last some realistic figures John well done you have obviously built a sweet little engine there enjoy ;)

Regards

Neil

Edited by ntc

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since i have put forward we need more rolling road graphs and car specs here are mine.

ive already posted the rolling road figures once.

 

engine rebored +20" and done about 3000 miles 170 ib compession figures

carbs SUs bae needles, later swept type manifold

air box fed from cold air from front of car via big air filter

phoenix 6.3.1 manifold to std type rear box.manifolds port matched,the exhaust needed quite a bit of grinding

219016 cylinder head from late 2.5 saloon skimmed apx 75thou.small [cr] exhaust valves with large [cp] seats

diy porting.3x angled valves and seats. valve and giudes shapes altered, im guessing stage 2/3

gt6 flywheel. dont think this will make any difference to hp.

lighter springs in dizzy but still got vacum advance fitted

cr camshaft.drain holes in tappets.

no mechanical fan and the heavy mounting.

a few gbox mods to reduce friction, with thinner oil. dont know if that would make any difference though.

richard

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richard,

That's interesting - you have exactly the same ditch in the torque curve between 2-2500.

What would cause that?

 

and thank you neil. Of course, a rolling road is the most blunt instrument known. There is no point at all in comparing outputs from different roads, only in figures from the same road, before and after mods. Trouble is, few have the time or resources to serially do mods and go back to the dyno, building up performance. The engine has indeed been very sweet to me - it is now pushing its third car towards the horizon, in nine years the first two having died under it.

Racing is a cruel sport, and after six racing seasons, it's age is showing, in oil leaks and increased crank pressure.

It's a 2 litre job for this winter, hope it does as well!

John

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Guest ntc
richard,

That's interesting - you have exactly the same ditch in the torque curve between 2-2500.

What would cause that?

 

and thank you neil. Of course, a rolling road is the most blunt instrument known. There is no point at all in comparing outputs from different roads, only in figures from the same road, before and after mods. Trouble is, few have the time or resources to serially do mods and go back to the dyno, building up performance. The engine has indeed been very sweet to me - it is now pushing its third car towards the horizon, in nine years the first two having died under it.

Racing is a cruel sport, and after six racing seasons, it's age is showing, in oil leaks and increased crank pressure.

It's a 2 litre job for this winter, hope it does as well!

John

 

Hi John

I have a cylinder head that might be of some use to you with your 2 litre project FOC pm me if interested

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