Tiff Needell's 1980 Rover V8 S SD1 Group 2 on our rollers
Discussion
We enjoyed running up the Group 2 SD1 race car built as a one off as a Works entry for the 1980 Tourist Trophy Race at Silverstone by David Price Engineering. The engine was a quad Webered, dry sumped 3.5 full race engine. It made 322.2 at the wheels giving 350 at the flywheel. The engine had previously been engine dynoed at 377 flywheel. It sounded awesome!
Here is a You tube link to the car being driven at Goodwood by Tiff Needell. Crank up the sound!
https://www.youtube.com/watch?v=7c6_okvdzGw
Here are some pics and a copy of the power graph
Here is a You tube link to the car being driven at Goodwood by Tiff Needell. Crank up the sound!
https://www.youtube.com/watch?v=7c6_okvdzGw
Here are some pics and a copy of the power graph
I know nothing really of the internals, I understand it was a Crower camshaft and I saw it was on 38 chokes, that is about it. Max timing for best power was 31.7 BTDC at 5000 rpm. With twin exhausts, one exiting each side infront of rear wheels it was a sort of stereo sex thing sat in the car running it, a bit like the ultimate sound surround arcade race game!
Peter
Peter
I did Mike, it reminded me of Mick Richards 3.9 TR8 from the early 90s, twin exhausts and like a horny toad when you were in it or near it or watched it on the track! I love the sound of all engines but the Vee engines with that off beat note do something for my soul 
I am 60 this year and feel blessed I still really enjoy what I am doing!
Peter
I am 60 this year and feel blessed I still really enjoy what I am doing!
Peter
I don't know much history of the car, I know it has done well even to survive as the MK1 SD1s were notoriously poorly built and rust buckets! I notice on the YouTube link my mate Ken Clarke has had some dealings with it ( he was a mechanic on the Touring Car SD1s with TWR). At present the car has a John Eales 3.5 litre dry sumped full race engine in it.
Peter
Peter
Hi Giovanni
The car hasn't raced much so not sure what class it is being prepped for.
The car will be on show at the London Classic Sports car Show this coming weekend.
With regard to torque maxima, the arguments go max torque per litre etc and discount the lbsft/litre achieved in 2v Nascar motors. If someone was claiming more than the 103 achieved commonly in Nascar and even 110 lbs/ft litre that would be an eye opener, but, when folk develop engines over a long period of time advances are made little by little. The same will obtain with the LS engines if they stay in race engine use as long as the X-flow, Pinto, A series, B series. Tr 4s and 6s and the venerable Buick derived V8 engines.
Just because folk haven't seen it thus far does not mean it does not exist.
The 3.5 in Tiff’s old car was a John Eales engine dynoed at 370 on his dyno. As fitted it gave 350 fly equivalent with our rollers.
Do you remember this topic I posted Dave?
http://www.pistonheads.com/gassing/topic.asp?t=149...
I also paste one of your replies where you stated:
“That second head has an identical flow curve to a John Eales (JE Motors) 43mm head I tested nearly 25 years ago and which I actually found nigh on impossible to beat which caused me some chagrin.”
Does this mean other V8s builders may find more power than you could?...allowing John a little more development work and I am sure he found a few more geegees over the years!
The engine mentioned in the above topic link went on to produce 390 flywheel bhp before we designed better inlet valves and the engine had a new cam with very rigid valve gear. Engine Bhp rose to approx 418 bhp. 3.9 with flat plane crank.
I attach a graph to compare the flat plane v8 3.9 with the Tiff Needell 3.5 engine.
PS, your transmission losses you stick to are and always have been a load of old cobblers you made up to justify your calculations. The number cannot be a constant as has been shown to you by many other posters on many other forums over the years, you just stick to it so your numbers make sense to you.
The one above, you have always said my dynos are all faulty and read wrong yet you use our wheel power to justify a fly figure from a different dyno. Sort yourself Dave, you are plucking numbers from a hat to try and justify your 'theories' to suit your machinations.
Peter
The car hasn't raced much so not sure what class it is being prepped for.
The car will be on show at the London Classic Sports car Show this coming weekend.
With regard to torque maxima, the arguments go max torque per litre etc and discount the lbsft/litre achieved in 2v Nascar motors. If someone was claiming more than the 103 achieved commonly in Nascar and even 110 lbs/ft litre that would be an eye opener, but, when folk develop engines over a long period of time advances are made little by little. The same will obtain with the LS engines if they stay in race engine use as long as the X-flow, Pinto, A series, B series. Tr 4s and 6s and the venerable Buick derived V8 engines.
Just because folk haven't seen it thus far does not mean it does not exist.
The 3.5 in Tiff’s old car was a John Eales engine dynoed at 370 on his dyno. As fitted it gave 350 fly equivalent with our rollers.
Do you remember this topic I posted Dave?
http://www.pistonheads.com/gassing/topic.asp?t=149...
I also paste one of your replies where you stated:
“That second head has an identical flow curve to a John Eales (JE Motors) 43mm head I tested nearly 25 years ago and which I actually found nigh on impossible to beat which caused me some chagrin.”
Does this mean other V8s builders may find more power than you could?...allowing John a little more development work and I am sure he found a few more geegees over the years!
The engine mentioned in the above topic link went on to produce 390 flywheel bhp before we designed better inlet valves and the engine had a new cam with very rigid valve gear. Engine Bhp rose to approx 418 bhp. 3.9 with flat plane crank.
I attach a graph to compare the flat plane v8 3.9 with the Tiff Needell 3.5 engine.
PS, your transmission losses you stick to are and always have been a load of old cobblers you made up to justify your calculations. The number cannot be a constant as has been shown to you by many other posters on many other forums over the years, you just stick to it so your numbers make sense to you.
The one above, you have always said my dynos are all faulty and read wrong yet you use our wheel power to justify a fly figure from a different dyno. Sort yourself Dave, you are plucking numbers from a hat to try and justify your 'theories' to suit your machinations.
Peter
Edited by PeterBurgess on Wednesday 22 February 06:46
And Donald also specialises in diverting attention. How come you took my 'plucked from the air', as you have described it in the past, wheel figure and extrapolated it with your guesswork figures to a fly figure of 370. From the build specs we don't think it was ever 370, we think it did very well to show 350 fly on our supaguessplucka number dyno. The original '370' engine had problems and has been stripped and built three times to get it back to where it is now. I don't suppose it even runs the same carbs and ex manifold and system as on engine dyno but you are hell bent on proving everyone wrong even to the extent of alternative facts....my wonky wheel power reading, your wonky maths to make it read 370 which was just a stated number from someone elses dyno not a gospel number.
Peter
Peter
Hi Dom
Around 13:1 long rods and short pistons.
We have never said our power figures are Gospel, we have always said we use the rolling road as a comparator tool and, as long as we get repeatable results day in and day out and we can compare and see slight changes as an increase or decrease in power we are happy, this has been especially so with our Dynocom inertia dyno. Once we get the Superflow dyno running, from talking to others, we will get similar discrepancies. I feel the real problem is, folk who do not actually work on rolling roads and engine dynos but only have access to occasional figures attribute too much to and from said figures,and don't spend time comparing figures from the same dyno or rolling road but heyho, what do I know, it is other folk who want to spend time poh-poohing the figures
A good use of the rollers is to see the differences in the 3.5 to 3.9 dogs dangly bits graphs shown above. You also have to remember we have many more graphs for all the cars we have done which gives us a lot of insight. We have probably tuned around 1500 cars on our new rollers.
Peter
Around 13:1 long rods and short pistons.
We have never said our power figures are Gospel, we have always said we use the rolling road as a comparator tool and, as long as we get repeatable results day in and day out and we can compare and see slight changes as an increase or decrease in power we are happy, this has been especially so with our Dynocom inertia dyno. Once we get the Superflow dyno running, from talking to others, we will get similar discrepancies. I feel the real problem is, folk who do not actually work on rolling roads and engine dynos but only have access to occasional figures attribute too much to and from said figures,and don't spend time comparing figures from the same dyno or rolling road but heyho, what do I know, it is other folk who want to spend time poh-poohing the figures
A good use of the rollers is to see the differences in the 3.5 to 3.9 dogs dangly bits graphs shown above. You also have to remember we have many more graphs for all the cars we have done which gives us a lot of insight. We have probably tuned around 1500 cars on our new rollers.
Peter
Hi Dom
I do not know fuel or what the head specs are. Our guesstimate is 91 lbs/ft litre from our figures. I know many pistoheaders think 80 is the limit but that limit is a mental limit and not a physical one or the Nascar 2valvers (remember they are actually restricted for mods so there would be more to come if restrictions were lifted) are running 103 with 110 I think having been seen according to a PH thread that David Vizard was involved in.
Sorry I cannot be of any further help, it isn't my engine build or headwork, just ran it up on my rollers to bed the refreshed engine in and make sure fuelling and timing was optimised.
I do feel the important thing is to see how different engines respond on the same dyno so comparisons are as genuine as can be. I would not use five different micrometers to measure one component and then use the possibly differing measurements to try and 'mean' something. Micrometer maybe not very good analogy as dynos are not as consistent as micrometers, mind you, micrometers can and do vary with temp
From my own point of view, whatever the 'true' figures are (whatever 'true' means) I have seen slow but steady power improvements over the 33 years I have been modding heads and tuning cars. Recently friction reduction is playing a large part and power to the wheels response improves dramatically with lightened components. As I said in an earlier post, the aggregation of marginal improvements. This slowly pushes the lbs/ft per litre upwards.
Peter
I do not know fuel or what the head specs are. Our guesstimate is 91 lbs/ft litre from our figures. I know many pistoheaders think 80 is the limit but that limit is a mental limit and not a physical one or the Nascar 2valvers (remember they are actually restricted for mods so there would be more to come if restrictions were lifted) are running 103 with 110 I think having been seen according to a PH thread that David Vizard was involved in.
Sorry I cannot be of any further help, it isn't my engine build or headwork, just ran it up on my rollers to bed the refreshed engine in and make sure fuelling and timing was optimised.
I do feel the important thing is to see how different engines respond on the same dyno so comparisons are as genuine as can be. I would not use five different micrometers to measure one component and then use the possibly differing measurements to try and 'mean' something. Micrometer maybe not very good analogy as dynos are not as consistent as micrometers, mind you, micrometers can and do vary with temp
From my own point of view, whatever the 'true' figures are (whatever 'true' means) I have seen slow but steady power improvements over the 33 years I have been modding heads and tuning cars. Recently friction reduction is playing a large part and power to the wheels response improves dramatically with lightened components. As I said in an earlier post, the aggregation of marginal improvements. This slowly pushes the lbs/ft per litre upwards.
Peter
A good hot bath and some Old Speckled Hen helps with the thought processes.
If I am preaching to those who already know the difference between graphs from wheel power and engine dyno graphs I apologise.
A graph of wheel power and engine power does not overlay with just more vertical power for the engine figures linearly. The tyres absorb power exponentially so, as the speed goes up, especially over 70 mph power absorption increases alarmingly, I am sure Stevie Turbo knows this all too well. So, below 70 losses are low, as far as I can see looking at wheel power versus engine dyno graphs ( I know one cannot say the two are comparable as they are different dynos but please bear with me) below 70 mph the wheel power is very close to engine power as transmission losses are very very low, above 70 mph and the tyre loses snowball so at high rpms the wheel power peaks some 500-700 rpm earlier than flywheel power because of the increase in power absorption of the tyres. This gives rise to truncated wheel power graphs. This is from comparing engine dyno graphs from many different dynos with our Clayton and Dynocom rollers. The problem with the exponentially increasing tyre losses with speed , tyre width and compound means Daves constant cannot hold true, the difference between a car doing 90 mph and 160 is stunning for tyre power absorption. We also move onto gearbox losses. Time and again we run MGBs with OE 4 speed boxes or Ford 5 speed boxes, the Fords sap around 3-4 bhp less than the OE Bs. Thinner gearbox oil and diff oil also reduces power losses and this readily shows up with power tests on an inertia dyno. These variations also throw cold water on Daves constants.
So, we come to the conclusion that one cannot really extrapolate from wheel power to flywheel power. We deal in wheel power as that is what accelerates the car, for instance, leave the handbrake on and all that lovely engine power goes nowhere! We use the coast down losses to compare cars with the same transmissions, we can see if there is a problem if losses higher than expected. However, people always want to know what the flywheel bhp is so we give a ballpark figure with the addition of wheel power and coastdown losses.
I posted the info on Tiffs old car as an interest item for a car with a lot of history which I felt folk may appreciate, I have owned 2 mk1 SD1s and I owned the Vitesse originally built for Harold Musgrove MD Rover, I have a soft spot for the SD1s. My mate Rog Parker worked with Rover and Michelin to develop the MK1 from a sloppy beastie to a taught good handling and well braked car which worked well for the Police. Rog's mate Phil designed the fuel injection setup for the Vitesse using a biscuit tin for the plenum I seem to recall, so, as I say I have a soft spot for SD1s.
Peter
If I am preaching to those who already know the difference between graphs from wheel power and engine dyno graphs I apologise.
A graph of wheel power and engine power does not overlay with just more vertical power for the engine figures linearly. The tyres absorb power exponentially so, as the speed goes up, especially over 70 mph power absorption increases alarmingly, I am sure Stevie Turbo knows this all too well. So, below 70 losses are low, as far as I can see looking at wheel power versus engine dyno graphs ( I know one cannot say the two are comparable as they are different dynos but please bear with me) below 70 mph the wheel power is very close to engine power as transmission losses are very very low, above 70 mph and the tyre loses snowball so at high rpms the wheel power peaks some 500-700 rpm earlier than flywheel power because of the increase in power absorption of the tyres. This gives rise to truncated wheel power graphs. This is from comparing engine dyno graphs from many different dynos with our Clayton and Dynocom rollers. The problem with the exponentially increasing tyre losses with speed , tyre width and compound means Daves constant cannot hold true, the difference between a car doing 90 mph and 160 is stunning for tyre power absorption. We also move onto gearbox losses. Time and again we run MGBs with OE 4 speed boxes or Ford 5 speed boxes, the Fords sap around 3-4 bhp less than the OE Bs. Thinner gearbox oil and diff oil also reduces power losses and this readily shows up with power tests on an inertia dyno. These variations also throw cold water on Daves constants.
So, we come to the conclusion that one cannot really extrapolate from wheel power to flywheel power. We deal in wheel power as that is what accelerates the car, for instance, leave the handbrake on and all that lovely engine power goes nowhere! We use the coast down losses to compare cars with the same transmissions, we can see if there is a problem if losses higher than expected. However, people always want to know what the flywheel bhp is so we give a ballpark figure with the addition of wheel power and coastdown losses.
I posted the info on Tiffs old car as an interest item for a car with a lot of history which I felt folk may appreciate, I have owned 2 mk1 SD1s and I owned the Vitesse originally built for Harold Musgrove MD Rover, I have a soft spot for the SD1s. My mate Rog Parker worked with Rover and Michelin to develop the MK1 from a sloppy beastie to a taught good handling and well braked car which worked well for the Police. Rog's mate Phil designed the fuel injection setup for the Vitesse using a biscuit tin for the plenum I seem to recall, so, as I say I have a soft spot for SD1s.
Peter
For instance the MAE 998 engine? Our guesstimates of one of the two we dyno was 80 lbs/ft per litre and 124 bhp/litre at the engine wheel peak torque 68 ish and max wheel bhp 100 at 7400 and 8250 respectively. Remember this is breathing through a single choke Weber (half a downdraft) and a restrictor, amazing really. It is music to the ears at 10000 rpm....1965 engine too!
Peter
Peter
Do you reckon Burt Munro accepted 'learned' maxima? Ooooh you can't get more than this or that? Race and record losers in the making
The bhp/litre measured at the flywheel or wherever can be improved with reducing friction and even more so by using fuel such as nitromethane so, to define limits and expectations, we have to look at the system boundaries and see if we can improve or push the boundaries. This is what I have done for 30+ years and continue to do so.
Take out the second compression rings and on bike engines we have seen improvement in bhp/litre, not due to better porting, cams, intake or exhaust, down to less friction.
At present we work with a guy who has pushed forwards TR4 bhp by hard work and maybe £150,000 research, people all round the world are involved and teamworking. It is paying off and the maximum bhp for a 2v race engine has been passed a couple of years back. Not on my wonky rollers either
Peter
The bhp/litre measured at the flywheel or wherever can be improved with reducing friction and even more so by using fuel such as nitromethane so, to define limits and expectations, we have to look at the system boundaries and see if we can improve or push the boundaries. This is what I have done for 30+ years and continue to do so.
Take out the second compression rings and on bike engines we have seen improvement in bhp/litre, not due to better porting, cams, intake or exhaust, down to less friction.
At present we work with a guy who has pushed forwards TR4 bhp by hard work and maybe £150,000 research, people all round the world are involved and teamworking. It is paying off and the maximum bhp for a 2v race engine has been passed a couple of years back. Not on my wonky rollers either
Peter
I don't quite understand you Dave. I have never said the figures I get are Gospel. You just spend your time trying to prove they aren't, I have told you, till the cows come home, I look for repeatability and use it as a tool to research improvements and tune cars. I realise there are limitations to rolling road tuning. In the not too distant future we will be using the engine dyno, this will mainly be research work for companies and race engines where we cannot get the car in to tune it on the rollers. I have no need of defending the figures, you obviously have a need to attack them!
With regard to max bhp litre and max lbs/ft litre be very careful of mentally imposed maxima or you will accept self imposed limits and, if you get back into the racing game (I don't know your track record as info seems scarce?) you will get hammered. I don't see limits, I keep striving and looking at the Nascar achievements on restricted regs as inspiration!
You remind me of Sextus Maximus Frontinus.........
I also lay aside all ideas of any new works or engines of war, the invention of which long-ago reached its limit, and in which I see no hope for further improvement...
- Sextus Julius Frontinus, governor of Britania, 84 C.E.
This one sounds like your rather frequent descriptions of me
It is difficult to deal with an author whose mind is filled with a medium of so fickle and vibratory a nature...; We now dismiss...the feeble lucubrations of this author, in which we have searched without success for some traces of learning, acuteness, and ingenuity, that might compensate his evident deficiency in the powers of solid thinking...
- Henry Brougham. [Criticizing Thomas Young's wave theory of light.]
I found those on this webpage of It'll never work. https://www.lhup.edu/~dsimanek/neverwrk.htm
Peter
With regard to max bhp litre and max lbs/ft litre be very careful of mentally imposed maxima or you will accept self imposed limits and, if you get back into the racing game (I don't know your track record as info seems scarce?) you will get hammered. I don't see limits, I keep striving and looking at the Nascar achievements on restricted regs as inspiration!
You remind me of Sextus Maximus Frontinus.........
I also lay aside all ideas of any new works or engines of war, the invention of which long-ago reached its limit, and in which I see no hope for further improvement...
- Sextus Julius Frontinus, governor of Britania, 84 C.E.
This one sounds like your rather frequent descriptions of me
It is difficult to deal with an author whose mind is filled with a medium of so fickle and vibratory a nature...; We now dismiss...the feeble lucubrations of this author, in which we have searched without success for some traces of learning, acuteness, and ingenuity, that might compensate his evident deficiency in the powers of solid thinking...
- Henry Brougham. [Criticizing Thomas Young's wave theory of light.]
I found those on this webpage of It'll never work. https://www.lhup.edu/~dsimanek/neverwrk.htm
Peter
Spot on Stevie, Karl at NMS and I reckon we should have monkeynuts for bhp, not sorted the torque yet
Sadly, Dave, we are not dealing in producing results to compare with everyone elses. I think only a few dynos will be calibrated enough to do that, and even then a person would be an idiot to use say three or four different dynos for testing? We always tell folk to use same dyno or dont even think about trying to compare. Take Superflow flow benches for example, it even says to do all work in one day if poss.
To be honest, I don't see many dyno firms posting graphs for you to analyse and compare on piston heads? Why don't you buy a dyno then you can show us all the way? When you do nothing but criticise my work it does look like sour grapes. After all, when you were friends with me you never tried to belittle me or my work even once, we worked together to move forwards and learn! It is sad to watch your bitterness and hatred gnaw away at you. You are much better than that Dave.
At the end of the day, I suppose, the truth of max bananas, curly wurlys or monkeynuts outs on the race track doesn't it? It is the effect of increasing the numbers that counts with me, as long as an increase in number is an increase and a decrease is a decrease and measurements repeatable then I am really content.
I shall continue to post graphs alongside any interesting (to me) cars when they come in while I get good responses.
Peter
Sadly, Dave, we are not dealing in producing results to compare with everyone elses. I think only a few dynos will be calibrated enough to do that, and even then a person would be an idiot to use say three or four different dynos for testing? We always tell folk to use same dyno or dont even think about trying to compare. Take Superflow flow benches for example, it even says to do all work in one day if poss.
To be honest, I don't see many dyno firms posting graphs for you to analyse and compare on piston heads? Why don't you buy a dyno then you can show us all the way? When you do nothing but criticise my work it does look like sour grapes. After all, when you were friends with me you never tried to belittle me or my work even once, we worked together to move forwards and learn! It is sad to watch your bitterness and hatred gnaw away at you. You are much better than that Dave.
At the end of the day, I suppose, the truth of max bananas, curly wurlys or monkeynuts outs on the race track doesn't it? It is the effect of increasing the numbers that counts with me, as long as an increase in number is an increase and a decrease is a decrease and measurements repeatable then I am really content.
I shall continue to post graphs alongside any interesting (to me) cars when they come in while I get good responses.
Peter
Excellent idea Dave, your writings are always good to read when you have given due consideration to the subject at hand.
May I suggest you start a new thread as this one was a posting to give an airing to a rare old beastie SD1, the only one ever made in this guise not a discourse on 2v and 4v, mind you, at the risk of diverting the thread further, did you know Rover experimented with 4v SD1 V8 heads before settling on a v6 for the Metro 6R4? I wonder what happened to those heads, I never got to see them but I think my mate Rog Parker did. It would be brill to see them on an engine wouldn't it?
Peter
May I suggest you start a new thread as this one was a posting to give an airing to a rare old beastie SD1, the only one ever made in this guise not a discourse on 2v and 4v, mind you, at the risk of diverting the thread further, did you know Rover experimented with 4v SD1 V8 heads before settling on a v6 for the Metro 6R4? I wonder what happened to those heads, I never got to see them but I think my mate Rog Parker did. It would be brill to see them on an engine wouldn't it?
Peter
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