Dyno's in the Leeds area
Discussion
Going this Saturday 
Done a pretty good deal on 4 cars considering their normal single car rate...
The bloke (not sure on the name but he runs the dyno I guess) was offering diagnostic power runs, where they run @ 500rpm intervals to max power, as well as a power run, and monitor a/f ratio and things at varying throttle openings.
All I'm after really is a power run, but I guess knowing how much fuelling I have as standard and when I go back after a remap (he also said he could remap it there!?) then I can see where the fuelling has been increased to offer more power etc.
All quite interesting. Just wondering if the diagnostic run is quite a common thing for people to have done, and how long it takes vs a straight power run at full throttle?
Thanks again for the recommendation Vixpy, seems like one of the best around after talking to them!
Dave
Done a pretty good deal on 4 cars considering their normal single car rate...
The bloke (not sure on the name but he runs the dyno I guess) was offering diagnostic power runs, where they run @ 500rpm intervals to max power, as well as a power run, and monitor a/f ratio and things at varying throttle openings.
All I'm after really is a power run, but I guess knowing how much fuelling I have as standard and when I go back after a remap (he also said he could remap it there!?) then I can see where the fuelling has been increased to offer more power etc.
All quite interesting. Just wondering if the diagnostic run is quite a common thing for people to have done, and how long it takes vs a straight power run at full throttle?
Thanks again for the recommendation Vixpy, seems like one of the best around after talking to them!
Dave
Well, was a good morning out.
Just curious though, because the Dyno Dynamics doesn't use coast down, it estimates losses.
My 306 Hdi hit 93bhp and book torque pretty much spot on. A perfect standard engine really.
My brothers Tdi which IS quicker got 92.5bhp and a bit less torque. Power fair enough, but the torque he gets is noticeably higher wrt to wheel spin etc.
Just curious that we all did runs in 3rd, and the Tdi engine is only getting into it's stride at 3000rpm, so is there a chance that as the boost kicked in the car ran off over 4000rpm and past peak power before the turbo actually got upto speed and the mechanical fuel pump compensator upped the fuelling?
I know coastdown is irrelevant here due to the method used, but is 3rd gear in a derv just too low to let the turbo spool up, with 60mph being @ 4000rpm in the said car?!?!
Felt happy with mine but it does have a smaller turbo and slightly longer gearing (afaik)... I imgaine if you did the run in 1st a turbo wouldn't even hit peak boost it'd be over the rev limit so quickly!?
Anyway, got 3 bhp over stock and about 15 lbft over stock
Better ring the insurers and tell them
Just look at the mental power output. 93bhp at 3200rpm, with 90bhp from 3000rpm>4200rpm!
No wonder you never feel the need to rev it! Hopefully some OBD port sparking will make it a bit better.
Dave
Just curious though, because the Dyno Dynamics doesn't use coast down, it estimates losses.
My 306 Hdi hit 93bhp and book torque pretty much spot on. A perfect standard engine really.
My brothers Tdi which IS quicker got 92.5bhp and a bit less torque. Power fair enough, but the torque he gets is noticeably higher wrt to wheel spin etc.
Just curious that we all did runs in 3rd, and the Tdi engine is only getting into it's stride at 3000rpm, so is there a chance that as the boost kicked in the car ran off over 4000rpm and past peak power before the turbo actually got upto speed and the mechanical fuel pump compensator upped the fuelling?
I know coastdown is irrelevant here due to the method used, but is 3rd gear in a derv just too low to let the turbo spool up, with 60mph being @ 4000rpm in the said car?!?!
Felt happy with mine but it does have a smaller turbo and slightly longer gearing (afaik)... I imgaine if you did the run in 1st a turbo wouldn't even hit peak boost it'd be over the rev limit so quickly!?
Anyway, got 3 bhp over stock and about 15 lbft over stock
Better ring the insurers and tell them
Just look at the mental power output. 93bhp at 3200rpm, with 90bhp from 3000rpm>4200rpm!
No wonder you never feel the need to rev it! Hopefully some OBD port sparking will make it a bit better.
Dave
Edited by Mr Whippy on Monday 17th July 15:53
Yes, I found an article on an Aussie site where they talk about this very problem, and the eddy current variable load rollers allow you to hold WOT at any rpm to let turbo's boost up before "letting the engine go" as it were.
Not sure if thats what they did now, but I guess they will have done.
Just curious, how long would you let one run for? Ie, do you relieve the rollers just enough so the engine pulls as if it's going up a hill just steep enough to allow acceleration, or is it fixed, so as a sudden torque boost rushes in the rollers speed up much quicker.
A diesel for example doesn't put up much of a fight at 1600rpm so the rate of rpm increase is low, but it suddenly spikes and so the rpm may "get ahead" of the turbo even at that load in such a low gear??
Is it worth me asking next time to have the engine labouring really hard, so it takes maybe 20 seconds to pass over the rpm range?
At least if thats possible then I can put my mind at rest about the turbo spool state and be satisfied the dyno represents WOT steady state full boost over the entire rpm range
Seem like a good dyno though, consistent and effective and I'm sure in respect to pure inertia dyno's they are way ahead!
Need to go back soon and ask lots more questions. Going to see if I can do a few varying tests with different intakes to asses the benefits!
AFR was also very telling, a very handy piece of information for a derv pre-tune since they run lean as standard and the more you tune them obviously the AFR slack is taken up!
Cheers for the help anyway Vixpy, think I couldn't have ended up at a better place for finding out/testing what I wanted to test
Dave
Not sure if thats what they did now, but I guess they will have done.
Just curious, how long would you let one run for? Ie, do you relieve the rollers just enough so the engine pulls as if it's going up a hill just steep enough to allow acceleration, or is it fixed, so as a sudden torque boost rushes in the rollers speed up much quicker.
A diesel for example doesn't put up much of a fight at 1600rpm so the rate of rpm increase is low, but it suddenly spikes and so the rpm may "get ahead" of the turbo even at that load in such a low gear??
Is it worth me asking next time to have the engine labouring really hard, so it takes maybe 20 seconds to pass over the rpm range?
At least if thats possible then I can put my mind at rest about the turbo spool state and be satisfied the dyno represents WOT steady state full boost over the entire rpm range
Seem like a good dyno though, consistent and effective and I'm sure in respect to pure inertia dyno's they are way ahead!
Need to go back soon and ask lots more questions. Going to see if I can do a few varying tests with different intakes to asses the benefits!
AFR was also very telling, a very handy piece of information for a derv pre-tune since they run lean as standard and the more you tune them obviously the AFR slack is taken up!
Cheers for the help anyway Vixpy, think I couldn't have ended up at a better place for finding out/testing what I wanted to test
Dave
Mr Whippy said:
Just curious, how long would you let one run for? Ie, do you relieve the rollers just enough so the engine pulls as if it's going up a hill just steep enough to allow acceleration, or is it fixed, so as a sudden torque boost rushes in the rollers speed up much quicker.
A diesel for example doesn't put up much of a fight at 1600rpm so the rate of rpm increase is low, but it suddenly spikes and so the rpm may "get ahead" of the turbo even at that load in such a low gear??
Dave
its all fixed in shootout modes (what your car was run in, and what all DD rollers should use), The rollers match the torque, so as to get a constant acceleration, this allows the turbo to spool properly.
Ah right, that sounds about right.
Kinda like how the diagnostic runs hold the revs, rather than the operator holding them per se, the rollers alter their resistance to match the torque output at any given rpm, hence holding the engine at WOT with no rpm increase.
So I guess in shootout the rollers automatically sense the torque of the engine across the rev range (effectively matching my dyno's "tractive lb" output) and match it equally, only allowing just enough resistance to let the revs proceed at a steady rate so a test of the rev range can be conducted
Makes alot more sense now. No matter what the engine the rollers just match the input from the wheels minus a bit. I guess that makes them more accurate as consistency is almost guaranteed and no car has an advantage for any reason...
Is there anything else these rollers can test for? A few people who went along with me had a diagnostic run done where you get low/med/wot measurements taken at 500rpm intervals, sounds even more interesting now I understand how the dyno works!
Thanks again for taking the time to answer my questions Vixpy. The operator on the day was happy to answer my questions but also really busy
Dave
Kinda like how the diagnostic runs hold the revs, rather than the operator holding them per se, the rollers alter their resistance to match the torque output at any given rpm, hence holding the engine at WOT with no rpm increase.
So I guess in shootout the rollers automatically sense the torque of the engine across the rev range (effectively matching my dyno's "tractive lb" output) and match it equally, only allowing just enough resistance to let the revs proceed at a steady rate so a test of the rev range can be conducted
Makes alot more sense now. No matter what the engine the rollers just match the input from the wheels minus a bit. I guess that makes them more accurate as consistency is almost guaranteed and no car has an advantage for any reason...
Is there anything else these rollers can test for? A few people who went along with me had a diagnostic run done where you get low/med/wot measurements taken at 500rpm intervals, sounds even more interesting now I understand how the dyno works!
Thanks again for taking the time to answer my questions Vixpy. The operator on the day was happy to answer my questions but also really busy
Dave
I'm not sure, I think it's about £50 +vat normally for a diagnostic power run.
We went and got a 4 cars (two power runs, two diag power runs, but could have had four diag power runs) for £180 PLUS vat wink wink...
I'll be going again in a few weeks hopefully so will let you know if you want. The more we get I guess the better deal we can get. Will be early though, I think the owner likes having guaranteed customers at 9am on a Saturday hence the good deal
Dave
We went and got a 4 cars (two power runs, two diag power runs, but could have had four diag power runs) for £180 PLUS vat wink wink...
I'll be going again in a few weeks hopefully so will let you know if you want. The more we get I guess the better deal we can get. Will be early though, I think the owner likes having guaranteed customers at 9am on a Saturday hence the good deal
Dave
vixpy1 said:
i would have done them the same way (3rd etc) the runs last long enough for the turbo to spool
Also, just wondering, why use 3rd gear?
Does the Dyno Dynamics software calc transmission losses effectively somehow?
Also, can the at wheels figure appear lower in different gears due to higher transmission losses in certain ratio's (ie, further away from 1:1)...?
Dave
Mr Whippy said:
vixpy1 said:
i would have done them the same way (3rd etc) the runs last long enough for the turbo to spool
Also, just wondering, why use 3rd gear?
Does the Dyno Dynamics software calc transmission losses effectively somehow?
Also, can the at wheels figure appear lower in different gears due to higher transmission losses in certain ratio's (ie, further away from 1:1)...?
Dave
Just the way its always been done on DD rollers mate (3rd for a 5 speeder, 4th for a 6 speeder) the loss program estimates, but does it excepetionally well, (its always matched production figs on cars which i know produce the power)
typically, on many dynos, the lower the gear, the higher the wheels fig. However, this is not the case with DD rollers, generally you can run them in 3rd or 4th the the wheel fig will vary by only a hp or two.
Ah good stuff...
Just a friend managed get 6bhp under on his 167bhp (stock) car...
Rekons it was because it was run in 3rd though it was a 6spd so maybe 4th would have been better.
Still, the operator noticed his top-end breathing was lacking (1.5 inHg over 5500rpm) and loosing him power.
He'd modded his intake with a trumpet with mesh grille over and I rekon that cost him alot of power, because the stock trumpet intake on a 306 is already hugely good, and I think he just totally ruined it
Will be going back in a few weeks anyway, so I guess we'll see then
Hope more of these DD rollers get used/bought, seem really good and consistent, just fairly few and far between up here in the North...
Dave
Just a friend managed get 6bhp under on his 167bhp (stock) car...
Rekons it was because it was run in 3rd though it was a 6spd so maybe 4th would have been better.
Still, the operator noticed his top-end breathing was lacking (1.5 inHg over 5500rpm) and loosing him power.
He'd modded his intake with a trumpet with mesh grille over and I rekon that cost him alot of power, because the stock trumpet intake on a 306 is already hugely good, and I think he just totally ruined it
Will be going back in a few weeks anyway, so I guess we'll see then
Hope more of these DD rollers get used/bought, seem really good and consistent, just fairly few and far between up here in the North...
Dave
Mr Whippy said:
Ah good stuff...
Just a friend managed get 6bhp under on his 167bhp (stock) car...
Rekons it was because it was run in 3rd though it was a 6spd so maybe 4th would have been better.
Dave
Just a friend managed get 6bhp under on his 167bhp (stock) car...
Rekons it was because it was run in 3rd though it was a 6spd so maybe 4th would have been better.
Dave
Was it a Gti-6 ? Because they rarely make the power, I've had them down at 150 sometimes..
vixpy1 said:
Mr Whippy said:
Ah good stuff...
Just a friend managed get 6bhp under on his 167bhp (stock) car...
Rekons it was because it was run in 3rd though it was a 6spd so maybe 4th would have been better.
Dave
Just a friend managed get 6bhp under on his 167bhp (stock) car...
Rekons it was because it was run in 3rd though it was a 6spd so maybe 4th would have been better.
Dave
Was it a Gti-6 ? Because they rarely make the power, I've had them down at 150 sometimes..
Yes it was, with a HUGE Magnex exhaust and a modified intake.
To be honest mine was lovely and nippy and felt 167bhp (if you can say that) when you really gave it some beans, but it was totally standard. (unfortunately never dyno'd it as I intended to leave it stock anyway... only reason I dyno'd my current car is so I have a start point for alterations).
I personally think touching any part of the system ruins the perfect setup in most modern day road cars. OK I bet you could loose refinement and low volume levels for a bit more, but at huge R&D cost and maybe only gain 2% say.
Ie, the stock compromise is about as good as you'll get, any better and it'll have to be serious motorsport development stuff.
Usually though these cars get good wheel power, but have silly drivetrain losses, some say 18% (though my Hdi 306 got ~ 22% apparently) but still made pretty much stock power (just a bit over)...
Who knows... main use to me for a dyno is for before and after and as a rough guide, not an absolute measure. His tyres or old gearbox oil or who knows what may have dropped his @ wheel figure by 4%, leaving the crank power down. Who knows, but exactly why consistency and testing is what dyno's are about imho... change tyres, re-run, see effects, remap ecu, leave all rest same, re-run etc etc
Thanks again Vixpy, he's taking it back when I go back. He ran stock wheels but with 50psi (seems to think that is better for wheel figures), and now wants to run in 4th or 5th. Problem is if he alters the intake now he won't know if it was the problem or not, so ultimately he needs to run 50psi again which just has no relevance to real life either... doh...
No winning with some people, just after the biggest numbers
Dave
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