|
|
Post Reply 
|
Page <1234> |
| Author | ||
UKDaveJ 
Really Senior Member II 
Joined: 18-November-2004 Location: Bromsgrove, Worcestershire Status: Offline Points: 529 |
 Posted: 19-February-2006 at 12:39 |
|
|
You need to probably get a leakdown test done Ivan, there is a procedure on bigcoupe forum for this - you could use a compression tester initially just to get an idea, but it won't be as thorough as the ld!
|
||
|
My 635's.
 
|
||
 |
||
| Sponsored Links | ||
|
||
|
86C
Newbie 
Joined: 27-November-2005 Location: Nottingham Status: Offline Points: 31 |
Posted: 19-February-2006 at 13:06 |
|
|
Good to meet some of you guys yesterday. Just need to find my own E24 now so I'm not the oddball with the Polo at these meets Not in any hurry though... The right one will come along eventually |
||
|
||
|
Brucey
Really Senior Member II
Joined: 07-March-2004 Location: United Kingdom Status: Offline Points: 744 |
Posted: 19-February-2006 at 14:16 |
|
me too... I reckon the white 75k auto highline should have been making about 230bhp- its been chipped and there is more to be had on one of these. I guess we'll never know now, but I suspect that the auto transmission losses may have been higher than the manual ones. We might be able to work it out from Tony's nitrous car- he had 150bhp jets in, but we only saw a fraction of that as a power increase on the giggle gas. My car has been timed 0-60 and is a little quicker than stock (despite the weight of the AC etc), so I doubt it is far away from stock power output, I was expecting about that or a touch more. BTW I filled up with 3/4 optimax, 1/4 95 octane. No comparative measurement available, and felt no difference through the 'backside dyno' whatsoever.... cheers
still, all a bit of a hoot |
||
|
~~~~~~~ Brucey ~~~~~~ |
||
|
||
|
Horsetan
Really Senior Member II
Say Neigh to Gatsos Joined: 11-April-2003 Location: Please let it be Ireland Status: Offline Points: 6381 |
Posted: 19-February-2006 at 14:22 |
|
Suddenly, that explains everything |
||
  
|
||
|
||
|
Brucey
Really Senior Member II
Joined: 07-March-2004 Location: United Kingdom Status: Offline Points: 744 |
Posted: 19-February-2006 at 14:51 |
|
there is quite a nice-looking '87 auto in red on e-bay right now, complete with style 32 alloys, and 107K on the clock. The tyres look funny sizes, but other than that it looks like a nice car. cheers
|
||
|
~~~~~~~ Brucey ~~~~~~ |
||
|
||
|
Drew540i
Really Senior Member II
Available from all good newsagents! Joined: 15-August-2005 Location: The Mansfield Massive Status: Offline Points: 632 |
Posted: 19-February-2006 at 15:18 |
|
|
Here's a reply I had from Geoff about Ross's low
powered red M6 and the possible cause of the problem.... " One thing that I would check is that the full load switch is working. Big rpm and 0.3 % CO sounds like part load operation . The idle/full load switch has a 3 pin plug. Centre is common . Pull the plug rubber boot back and put a meter down the back of the plug on one of the outside pins ( plug connected to switch ) Ignition on -Operate the throttle . If it moves volts immediately that the idle connector. Move to the other outside pin and try full throttle. Should get the same meter response as idle. See what happens . I have replaced loads of those idle/full load switches for full load switch failure !!! The idle switch is a microswitch- you can hear it going on off. The full load is a wiping contact type and it stops wiping !!! Who knows £15 for loads of bhp !! See if the switch thing makes sense but I think that could be the reason for p*ss poor fueling. The late M6s were calibrated a bit different to the originals so a rechip could be a plan even with the switch working." There you go Ross - a plan could be to take the car to Ray at West Tuning (Thruxton 01264 773839) who does stuff with Geoff on the dyno most of the time. Sorting the mega weak running and a rechip is all very possible. Feel free to PM me for a chat about stuff! 
|
||
|
||
|
UKDaveJ
Really Senior Member II
Joined: 18-November-2004 Location: Bromsgrove, Worcestershire Status: Offline Points: 529 |
Posted: 19-February-2006 at 15:51 |
|
Looks nice! Missing the rad fan-shroud, also in the close up shot of the osf wheel you can see what looks like overspray on the mudshield!  |
||
|
My 635's.
|
||
|
||
|
UKDaveJ
Really Senior Member II
Joined: 18-November-2004 Location: Bromsgrove, Worcestershire Status: Offline Points: 529 |
Posted: 19-February-2006 at 17:37 |
|
|
I thought the following of interest.
HERE According to my Highline's owners manual, it's rated at 211 bhp (DIN 70020 standard) at 5700 rpm. Achieving a rear wheel figure of 142bhp at 5226 rpm equates to about a 32% loss, considerably more than indicated in the link above, which suggests 20% loss for auto transmission. That would have improved things a bit, 169bhp! |
||
|
My 635's.
|
||
|
||
|
AndyS
Really Senior Member II
The Last of the Few Joined: 21-August-2003 Location: 55 � North Status: Offline Points: 1365 |
Posted: 19-February-2006 at 17:49 |
|
|
Glad you all enjoyed it, shame I couldn't make it.
One thing that should be borne in mind is that the figures obtained were for that dyno (& to a much lesser extent, that day). Dynos, like engines, do differ & that one could have been under reading slightly. This is why it's important to use the same dyno when measuring before & after mods. Differing atmospheric conditions can give differing results too. The one constant is that the figures obtained can be compared to the other cars tested. I remember a figure of 30% being mentioned for transmission losses so 40% isn't too far off. Don't forget these autos have lockup so don't lose as much power as older types. Remember, when Total BMW did a group test with some E30's no standard car matched the manufactures figure. |
||
|
AndyS
Live each day as if it's your last - one day it will be. 
|
||
|
||
|
Horsetan
Really Senior Member II
Say Neigh to Gatsos Joined: 11-April-2003 Location: Please let it be Ireland Status: Offline Points: 6381 |
Posted: 19-February-2006 at 18:14 |
|
|
Given that I poisoned everyone yesterday, this explains a lot |
||
|
|
||
|
||
|
Drew540i
Really Senior Member II
Available from all good newsagents! Joined: 15-August-2005 Location: The Mansfield Massive Status: Offline Points: 632 |
Posted: 19-February-2006 at 18:48 |
|
Yes, up to a point but even an old system like Motronic 3 does (sort of) take Barometric pressure into account - it will do more power on a really cold damp though. Ye cannae beat the law of physics! It was in fact a chilly day and the doors of the dyno cell were wide open. At the end of the day, 211 bhp was on an engine dyno with a perfect new engine and was the best of numerous runs. The M30 is a prehistoric thing used to power Heinkel bombers in WW2 and 200 bhp is about your lot for a decent standard one. As for the E30 dyno shoot out you mention, a few cars did get within 5 bhp of the standard figure - namely the standard unmolested ones. |
||
|
||
|
Drew540i
Really Senior Member II
Available from all good newsagents! Joined: 15-August-2005 Location: The Mansfield Massive Status: Offline Points: 632 |
Posted: 19-February-2006 at 18:58 |
|
|
A 20% power loss through an old 4HP22 is just
dreaming - when these were being run up they were in 3rd gear only without the converter lock up. Trust me - these cars were doing around 200-210 bhp! Nothing disgraced itself and had there been a converter lock up in the lower gears, they would have shown more power. |
||
|
||
|
Brucey
Really Senior Member II
Joined: 07-March-2004 Location: United Kingdom Status: Offline Points: 744 |
Posted: 20-February-2006 at 00:45 |
|
|
hmm, 'old' motronic 3??? Most of the cars there were running motronic 1.0... just temperatures and airflow, and even on the M30 engine, a WOT fuelling strategy that relies on the throttle sensor working OK. We had a good mix of stock and slightly modified engines; if there had been a few outliers then fair enough, but all the auto gearbox cars were well down on rear wheel bhp which points to the conclusion that the transmission losses were very large, especially when they are as quick or better than stock on the road, i.e. auto slower than manual. I was trying to figure out a way of using the top gear lock-up to make it more efficient; thing is, it would have tried to kick down at any speed below about 140mph on the rollers.... cheers
|
||
|
~~~~~~~ Brucey ~~~~~~ |
||
|
||
|
UKDaveJ
Really Senior Member II
Joined: 18-November-2004 Location: Bromsgrove, Worcestershire Status: Offline Points: 529 |
Posted: 20-February-2006 at 04:52 |
|
|
So, even the figures achieved at the rear wheels on the auto cars were not with transmission lock, therefore more bhp would have been possible had the lock been in place??!!
I've never had an auto car on the rollers before, so it was quite an experience. If the auto cars were run through the box (as normal) but without hitting the point on the throttle where the kick-down switch operates, would they still have got to a WOT position in 4th & therefore potentially higher rear-wheel figure as the transmission would have locked out? On mine, you can easily tell when you are about to kick down, the throttle feels quite stiff (like its reached max downward travel), that extra push will cause the kick-down to operate. I'm not disappointed with the results, far from it, just was wondering having looked at the figures how James' manual 635 showed such apparent massive transmission losss, considerably more than that of the speculated 'flywheel' figures of the autos in comparison with their achieved rear wheel achieved figures. I hadnt realised that the transmission didn't lock up in 3rd, therefore more would have been capable from the auto's as Drew540i indicates had they locked! Was this lack of tranmission lock partly to explain why the torque figures seemed quite low on some of the auto cars, mine showed 168lbs/ft on the graph at 4000rpm then tailed away massively? I think all the cars ran well with very few exceptions & they were either due to age, mileage or need for some garage fettling. According to my Road Angel GPS speed readout, myself, Craig & rpmMark were making very good 3 figures progress up the M40 on the way home.......... My graph  Edited by UKDaveJ |
||
|
My 635's.
|
||
|
||
|
UKDaveJ
Really Senior Member II
Joined: 18-November-2004 Location: Bromsgrove, Worcestershire Status: Offline Points: 529 |
Posted: 20-February-2006 at 08:18 |
|
Interesting! How come James's manual 635 showed 159bhp at the wheels & 222bhp at the flywheel? Thats a massive loss through the transmission (near as dammit 28%), not far off what the auto's seemed to theoretically lose? Does the dog-leg manual box really lose that much in comparison to the auto box? |
||
|
My 635's.
|
||
|
||
|
AndyS
Really Senior Member II
The Last of the Few Joined: 21-August-2003 Location: 55 � North Status: Offline Points: 1365 |
Posted: 20-February-2006 at 09:12 |
|
It does. Once the gear has engaged the clutch locks up to avoid torque convertor slip. This is not the same as using the 3-2-1 position to lock a gear. This is one of the reasons the auto has such good economy & performance not far short of the manual & was a major improvement over the 3 speed predessor. At a steady speed in 3rd there would be no more slip than with a manual. I have seen no figures to suggest the 4HP22 in 3rd gear would have higher losses than the manual in 3rd or 4th. There is is good article from a transmission specialist on the net about the 4HP22 transmission which I found from the Roadfly forum, going into great detail about the design. The Highlines used a later version of Motronic - 3.3 iirc. |
||
|
AndyS
Live each day as if it's your last - one day it will be.
|
||
|
||
|
AndyS
Really Senior Member II
The Last of the Few Joined: 21-August-2003 Location: 55 � North Status: Offline Points: 1365 |
Posted: 20-February-2006 at 09:34 |
|
The flywheel power wasn't measured - you can only do that by removing the engine & strapping it to an engine dyno. The flywheel power was estimated from the estimated transmission power losses. In fact the bhp figure was obtained from the torque at the rear wheels - lb/ft, newton/metres, kg/m whatever. It was then converted to "brake horse power" which, simply put, is torque x revs. Huge power Yank engines were quoted using SAE which meant using an engine dyno without ancillaries such as alternators, power steering pumps etc. Once in a car it was a whole different story. So, given that you can't be 100% sure of the flywheel power, have no guarantee that the engine produced the full 218 or 220 Highline power (211bhp was from the E34 535) when it was new let alone with 100k miles under it's belt or indeed the accuracy of the rolling road, it's difficult to quote absolutes. What you can say is that on that dyno that Six gave Xbhp at the wheels compared to the other Sixes that were tested too. From the torque & power curves you can see where flat spots or other problems are occuring - as some of you found out. |
||
|
AndyS
Live each day as if it's your last - one day it will be.
|
||
|
||
|
Sohlman
Really Senior Member II
Coupe Chairman Joined: 19-August-2003 Location: Surrey Status: Offline Points: 1259 |
Posted: 20-February-2006 at 10:53 |
|
|
I will post up my power figure soon. I just have to scan the sheet in. The curve is now much flatter and does not have a dip which it had on the last run and power and torque are up right the way across the dyno run. 29% transmission loss for my car sounds about right as the gearbox is a little tired as is leaking slightly. I have a spair mind you. For reference my car has the overdrive box and not the dog leg. James |
||
 Sunday 10th July Brooklands Sharkfest and Big Coupe Day. Coupe Events
|
||
|
||
|
UKDaveJ
Really Senior Member II
Joined: 18-November-2004 Location: Bromsgrove, Worcestershire Status: Offline Points: 529 |
Posted: 20-February-2006 at 11:29 |
|
|
Thanks Andy & James, most interesting!
I for one would definitely like to see more graphs, then its possible to work out other details from them. Figures on their own only give one part of the overall picture. I think my torque figs might well be down due to a blowing manifold, but other than that I don't know. To participate in this exercise was one thing, to usefully learn from it is quite another!! |
||
|
My 635's.
|
||
|
||
|
brybusa
Really Senior Member II
Joined: 02-December-2004 Status: Offline Points: 676 |
Posted: 20-February-2006 at 11:42 |
|
|
Interesting that on the day the rear wheel 159BHP wheel bhp figure equated to a calculated 222BHP, when my E34 535 manual (re-mapped)car was dyno'd @ G - Force the rear wheel figure was 160BHP and the fly figure estimated was 205BHP... I cant see a chipped 3.5 making 230BHP IMHO
|
||
|
||
|
Post Reply
|
Page <1234> |
|
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
E24 6 series Rolling Road Shootout
Topic Options
Sohlman wrote:
