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Rnash2002
Monday 25th April 2011, 12:52
Ok does anyone know of a site or if they know the gearbox ratios in a m59 box and a box on a c70 t5 me7,or is the c70 a m56 box?

Reason i ask is when i timed a 60 to 100 mph run in the c70 it was quicker than my 850 t5 with the k24 but was way lower bhp and lbft figures when on the dyno.

Wobbly Dave
Monday 25th April 2011, 13:56
Our cars are both running M56 boxes. I believe the ratios remain unchanged.

Rnash2002
Monday 25th April 2011, 15:04
Our cars are both running M56 boxes. I believe the ratios remain unchanged.
Cheers Dave,that takes that out of the equation then,any chance you could time a 60 to 100 mph? lol

smithy
Monday 25th April 2011, 17:42
we will see how fast the car is on the strip mate

Wobbly Dave
Monday 25th April 2011, 20:50
Hi, I have been looking over my old chits from the quarter miles & looking over my old vid from May last year. About 10 seconds in 4th (I think this is 4th?)

Sadly I don't seem able to upload this video directly.

Here is the 4th gear vid...

http://www.youtube.com/watch?v=UvedfROlge4

Wobbly Dave
Monday 25th April 2011, 21:12
3rd Gear

http://www.youtube.com/watch?v=xyZX5HVnOLA

jardon
Monday 25th April 2011, 22:33
There are different final drives in M56 boxes depending on car and year but I don't know what those ratios are. Was there an M56L and M56H or am I making it up?

Rnash2002
Tuesday 26th April 2011, 00:05
3rd Gear

http://www.youtube.com/watch?v=xyZX5HVnOLA
I take it you have your limiter raised? as it didnt sound like you changed gear?

Wobbly Dave
Tuesday 26th April 2011, 00:17
The car will run upto approx 72 in second, ~ 110 in 3rd, about 140 in 4th & off the clock in 5th. My red line is about 7200. It has been raised on this map.

I am able to stay in 3rd on the drag & complete doing a top speed measured at 103 & I was almost out of revs.

That applies to the slightly older box (which came off an S70 I believe) which has the ATB in it & the original gearbox.

I will get confirmation in the next few days about the ratios - as the new box is currently back in the workshop being investigated.

Rnash2002
Tuesday 26th April 2011, 12:40
Ok so when these were taken you were running 300bhp?

Ive done the same runs today in mine as she is and put my foot down from 60 like you have heres mine and your times.

Mine


60 to 100 3rd and 4th gear = 7.03 (Have to change as limiter still stock)
60 to 100 4th = 8.15

Dave

60 to 100 3rd = 6.97
60 to 100 4th = 9.68

Now i just cant see mine making 256 bhp and 300 lbft to be beating yours in the 4th gear run and very close in the 3rd to 4th also take a few tenths to change gear aswell lol.

T5frankie
Tuesday 26th April 2011, 12:45
Ok so when these were taken you were running 300bhp?

Ive done the same runs today in mine as she is and put my foot down from 60 like you have heres mine and your times.

Mine


60 to 100 3rd and 4th gear = 7.03 (Have to change as limiter still stock)
60 to 100 4th = 8.15

Dave

60 to 100 3rd = 6.97
60 to 100 4th = 9.68

Now i just cant see mine making 256 bhp and 300 lbft to be beating yours in the 4th gear run and very close in the 3rd to 4th also take a few tenths to change gear aswell lol.


remember dave's has a 19t so in fourth wont come on boost till much after your 16t so thats why his time is slower in fourth but not third

Rnash2002
Tuesday 26th April 2011, 12:55
remember dave's has a 19t so in fourth wont come on boost till much after your 16t so thats why his time is slower in fourth but not third

Yes but i have to change from 3rd to 4th and that would lose me somtime.
Im just struggling to see why mine only made 256bhp when its as quick as a 300bhp c70 and also slighlty quicker than my 850 was with the k24 on it.
Dont get my wrong im not complaing at all as she feels good on the road.

T5frankie
Tuesday 26th April 2011, 13:11
Yes but i have to change from 3rd to 4th and that would lose me somtime.
Im just struggling to see why mine only made 256bhp when its as quick as a 300bhp c70 and also slighlty quicker than my 850 was with the k24 on it.
Dont get my wrong im not complaing at all as she feels good on the road.

but he is about 700 rpms off boost in 4th that takes more than a few tenths, remember my car only made 262bhp with the 18t at 22psi at 4000rpm that too felt rapid on the road but not on the track, you going to york?

Wobbly Dave
Tuesday 26th April 2011, 13:25
According to my map my boost starts around 3K but will not be fully in till 3500 - 4000. I am only running 0.9 bar at WOT. The 300 figure is explained by the long torque curve that remain high right the way through till about 5500. Peak figures are not always the best explaination. It is the area under the torque curve that gives the game away.

http://www.vpcuk.org/forums/attachment.php?attachmentid=9839&d=1288918938

Rnash2002
Tuesday 26th April 2011, 16:23
but he is about 700 rpms off boost in 4th that takes more than a few tenths, remember my car only made 262bhp with the 18t at 22psi at 4000rpm that too felt rapid on the road but not on the track, you going to york?

I see where you comming from but im also going on my 850 with the k24,now that wouldnt be on boost as quick as the 16t.
Yes i will be at york,if i can i might try and get down sooner as im itching to see what she runs like.


According to my map my boost starts around 3K but will not be fully in till 3500 - 4000. I am only running 0.9 bar at WOT. The 300 figure is explained by the long torque curve that remain high right the way through till about 5500. Peak figures are not always the best explaination. It is the area under the torque curve that gives the game away.

http://www.vpcuk.org/forums/attachment.php?attachmentid=9839&d=1288918938

I do see and understand this but i thought it was the lbft's that pull the car along so the higher they are the quick it should pull you along?

T5frankie
Tuesday 26th April 2011, 16:29
I see where you comming from but im also going on my 850 with the k24,now that wouldnt be on boost as quick as the 16t.
Yes i will be at york,if i can i might try and get down sooner as im itching to see what she runs like.



I do see and understand this but i thought it was the lbft's that pull the car along so the higher they are the quick it should pull you along?

thats what made my car so quick on the road cos it had 335lbs ft torque (455nms) made all its power at 4k. i think daves car has high bhp but quite low torque compared to some thats why his car only gets moving after 1/8th mile my car is the other way round quite high torque but relatively low bhp thats why my car is crap on the second half of the quarter

Wobbly Dave
Tuesday 26th April 2011, 20:21
I see where you comming from but im also going on my 850 with the k24,now that wouldnt be on boost as quick as the 16t.
Yes i will be at york,if i can i might try and get down sooner as im itching to see what she runs like.



I do see and understand this but i thought it was the lbft's that pull the car along so the higher they are the quick it should pull you along?
torque give you the acceleration. Power gives the speed. So if the torque remains high the acceleration should not disipate as fast even though this is balanced against the drag (moving the air out of the way) + friction from the tyres + overcoming the inertia.

I am no physicist but I know that the car moves well. We shall see at York no doubt.

Wobbly Dave
Tuesday 26th April 2011, 20:26
thats what made my car so quick on the road cos it had 335lbs ft torque (455nms) made all its power at 4k. i think daves car has high bhp but quite low torque compared to some thats why his car only gets moving after 1/8th mile my car is the other way round quite high torque but relatively low bhp thats why my car is crap on the second half of the quarter
I dare say I am not making the same volume of airflow through the induction system in 2nd as the 16T - boost will be lower hence I am not making much headway on the drag strip until 3rd - hence the high speed finishes (103) but relatively slow times 14.7 so far this season. Best 60 ft was 2.4 seconds.

T5frankie
Tuesday 26th April 2011, 20:35
I dare say I am not making the same volume of airflow through the induction system in 2nd as the 16T - boost will be lower hence I am not making much headway on the drag strip until 3rd - hence the high speed finishes (103) but relatively slow times 14.7 so far this season. Best 60 ft was 2.4 seconds.

whats your best 1/8th mile dave?

Wobbly Dave
Tuesday 26th April 2011, 22:22
been looking for my old slips - what I can find - which is not a lot is about 9 seconds for the 1/8th mile.

Ed.
Tuesday 26th April 2011, 23:33
been looking for my old slips - what I can find - which is not a lot is about 9 seconds for the 1/8th mile.

That doesn't seem to add up? Your 60ft time is 2.4s which i reckon is pretty average at best for a manual t5, but your 1/8th mile is 9s, which is very quick! but then your 1/4 mile is 14.7@103 which is slowish.

What speed are you doing at 1/8th mile?

Just had a glance at my slips from earlier this month and my best run had a 60ft of 2.6. My 1/8 is 9.56@79mph and my 1/4 is 14.52@101mph. My 4spd auto changes up to 3rd at around 83mph.

Ed

Wobbly Dave
Tuesday 26th April 2011, 23:50
My 8th is similar - but I have lost or thrown away the tickets. My 8th was around the 76 mph mark. Why is it odd?

Rnash2002
Wednesday 27th April 2011, 08:11
Heres mine from the 850.

http://img.photobucket.com/albums/v489/rnash2002/img016.jpg

t5_monkey
Wednesday 27th April 2011, 08:41
I got 99.8 @ 15s flat at Crail.

Mostly down to a poor start and little traction off the line (or driver error!)

a really good driver could probably crack 14.5 in mine if not lower - driver input will always affect the figures significantly.

Santa (4WD S60R) gets sub 14 on the strip with a terminal around 101-102mph, so traction is a huge factor.

p fandango
Wednesday 27th April 2011, 09:50
I got 99.8 @ 15s flat at Crail.

Mostly down to a poor start and little traction off the line (or driver error!)

a really good driver could probably crack 14.5 in mine if not lower - driver input will always affect the figures significantly.
should get lower than that, i got 14.557@99.1mph in BT with standard map, MBC, decat, 15g & an interior lol

T5frankie
Wednesday 27th April 2011, 11:00
WOrk mine out then I got a 2.2 60ft 76 mph at 1,8th mile and terminal was 14.79@93mph

Ed.
Thursday 28th April 2011, 00:48
Quite interesting seeing the interval times and speeds from the slips It gives a good idea of how the car is tuned, where the power comes in, etc.

Dave's time is odd because as i mentioned 9.0s 1/8 is very quick, but the speed 76mph isn't that high. Bearing in mind Dave would have changed gear twice by 1/8 mile, would suggest that your car is boosting well, even in the lower gears after getting past the turbo lag.

If you compare with Russ' 850, he also does 9s 1/8 but he is at 83mph, which is more like it.

Ed

Wobbly Dave
Thursday 28th April 2011, 00:56
I cannot say exactly for my best time of 14.7 what my 1/8th mile time & speed was. It was approx. 9 to 10 seconds at somewhere around the 75mph mark

Ed.
Thursday 28th April 2011, 01:11
No probs Dave. I reckon if your boost started coming in earlier, say 2500rpm at 5-7psi then you would see improvements both on track and on the road too.

I would also say that Russ' C70, with it being an ME7 car will have quite a few of the mods that us 850 drivers want as standard. If i'm not mistaken, the C70 would already have the ME7 manifold, angled 16t, 2.75" downpipe and possibly vvt as well. These would certainly make it pull better, add to that a good progressive map and you are well on the way to a fast road car. Dyno figures might not show it, but its how it drives in the real world that counts.

Ed

Wobbly Dave
Thursday 28th April 2011, 14:54
The nature of the 19T is such that it doesn't come in that early. I have not seen anyone push boost before 3k on a 19T - I could be wrong.

The basis of both our cars is the same ME7 setup. I keen to see how we fair at York.

t5_monkey
Thursday 28th April 2011, 15:13
I get 100mph on the 1/4 and my turbo is the size of a pencil sharpener!

Not all about how big your turbo is :)

jardon
Thursday 28th April 2011, 15:47
The nature of the 19T is such that it doesn't come in that early. I have not seen anyone push boost before 3k on a 19T - I could be wrong.

The basis of both our cars is the same ME7 setup. I keen to see how we fair at York.

Again, I have to disagree Dave. On my car with identical ME7 and 19t (perhaps laggier due to turbine clipping) I make almost 0.7 bar at 2500 rpm, 1.2 bar by 3000 rpm and 1.4 bar by 4000 rpm. My car pulls from 2000 rpm and things get going from around 2700 rpm. If I experimentally run the stage 1 map with all the custom mods it will try to go off the boost gauge as the BCS duty is all wrong ie: the 19t will boost it's pants off from low rpm if allowed too. If mapped not too provide low end torque then it won't but believe me it's not due to any inherent mechanical restriction on the part of the turbo - increased BCS duty = more torque and reduced BCS duty = less torque.

A 19t is just a 16t with a slightly larger compressor wheel - nothing different otherwise (same CHRA and turbine). My car is into positive boost at less than 2000 rpm and has been for 3 years with no ill effect. With flow mods that encourage earlier spool (DP and catback) my 19t pulls much stronger than my 16t used to at low rpms. The difference is in the mapping - a 19t is not a big turbo and it's piddly turbine will spool just like a 15g.

Edit: I haven't seen any 19t'd cars making less than 1.2 bar at 3000 rpm. The joy of the 19t wheel proportions are flexibility - early spool, good mid range and reasonable top end.

Wobbly Dave
Thursday 28th April 2011, 16:03
I guess things will change once my map is finally finished.

Rnash2002
Thursday 28th April 2011, 17:39
The basis of both our cars is the same ME7 setup. I keen to see how we fair at York.
Might have a 19t on it by then lol

Wobbly Dave
Thursday 28th April 2011, 18:13
To be honest I am looking forward to it. It feels like I have been the lone developer of ME7 in a C70 for some time.

It will be good to compare notes.

T5frankie
Thursday 28th April 2011, 18:37
Might have a 19t on it by then lol

if you can find one lol

p fandango
Thursday 28th April 2011, 19:23
The nature of the 19T is such that it doesn't come in that early. I have not seen anyone push boost before 3k on a 19T - I could be wrong.
i'm only running 10psi at the minute, but now spools up as quick as my 15g did

Rnash2002
Thursday 28th April 2011, 20:13
if you can find one lol
Ive found a brand new one for a very good price,also spoke to the company to make 100% sure it was a 19t.
Once ive got one in hand and are happy with it being a proper 19t then i will let you know where i got it from.

T5frankie
Thursday 28th April 2011, 21:09
Ive found a brand new one for a very good price,also spoke to the company to make 100% sure it was a 19t.
Once ive got one in hand and are happy with it being a proper 19t then i will let you know where i got it from.

my car has one fitted mate