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limpabit 11th June 2014 06:50

Drag racing
Went drag racing last weekend. Did four runs. Only casualty this weekend, have no lights or instruments. Think it's just a fuse. But drove home unlike before when I came back on a truck due to the drive shaft popping out.

My main problems is getting into second gear. Told by the drag guys is a common problem. Need to stop trying to change gear while bouncing off the rev limiter in first! But adrenaline etc! 3 out of the 4 runs I did this.

Best time was 13.38 1/4 & 102 top speed. With practice, hit the 12's and 110 is my next target.

Cars raced
Pug 106 modded 1.6 turbo. No contest and won by a few seconds. No dodgy gear changes

Evo 5??? 275 BHP. My worse run and gear change. But only just lost. This was a 14.9 run it was that bad

Modded Scobby Sti. Beat quite easy and into 13's again with dodgy gear change.

Modded Mx5 totally no contest. Few seconds again beat him. He was a touch annoyed. Still with a dodgy gear change into the 13's.

And the amount of people that come up asking afterwards. What the heck is it. Looked quick out there. Never seen one before etc.

MadDogMoggy 17th June 2014 11:29

Could you pull away in 2nd?

IVA tester said I shouldn't need first due to the power to weight ratio. Have to admit I only use 1st if stuck in slow moving traffic or doing a steep hill start, otherwise 2nd gets me away quick without an awkward gear change after 1/2 a second!

limpabit 17th June 2014 14:07

Might give that a try and play.

What are you running in yours? Rover PG1?

MadDogMoggy 18th June 2014 11:44

K20A2 (civic type R).

It's also a 6 speed box which may help - I think the overall spread of ratios is similar to a 5 speed box, they're just closer together.

I think I could get away with just 2nd, 4th and 6th!

limpabit 18th June 2014 12:12

I've heard that before about the K20 box being very low geared. Think X cars mini actually block off 1st gear. Do you have the ratios by any chance so I can compare?

The gearing in the 200 pg1 is high for first gear. But will have a play in 2nd.

220 turbo ratios as standard
'K' (1)= 2.923 (2)= 1.750 (3)= 1.222 (4)= 0.935 (5)= 0.765
Fd '7' is 3.647 (17/62)

MadDogMoggy 19th June 2014 12:48

From memory (lol):

1st 3.266
2nd 2.13
3rd 1.517
4th 1.147
5th 0.921
6th 0.738

Final drive 4.764

It will drive at 30mph at about 1500rpm in 6th, which gives a (theoretical) top speed of 160mph at 8000 rpm (running 195/50/15s)

Crunching the numbers, it's nearer 1600 RPM assuming a rolling circumference of 1.757 metres:

1 mile = 1.609344 Km
1 mile = 916 tyre revolutions
30 miles = 27480 revolutions
30 MPH = 27480 revs/hour
30 MPH = 458 revs/minute
tyre revs/min * Final Drive * 6th Gear Ratio = Engine rpm
Engine RPM = 458*4.764*0.738
=1610 RPM

Don't know if any of that helps (especially as I went off on a tangent!)

limpabit 25th June 2014 06:09

Did the compare using 195/55/15 and Hpnda gear change at 6500

Rover first gear is not far from Honda second! Honda has a lot lower 1st gear ratio. But will give it a try.

Top Speed in 1 gear = 39.360 MPH
And changes into 2 gear at 3712 RPM dropping 2488 RPM
Top Speed in 2 gear = 65.743 MPH
And changes into 3 gear at 4329 RPM dropping 1871 RPM
Top Speed in 3 gear = 94.149 MPH

Top Speed in 1 gear = 28.272 MPH
And changes into 2 gear at 4239 RPM dropping 2261 RPM
Top Speed in 2 gear = 43.350 MPH
And changes into 3 gear at 4629 RPM dropping 1871 RPM
Top Speed in 3 gear = 60.867 MPH

EXI Turbo 4th July 2014 18:42

Sounds great fun and car must be well sorted. I would love to feel safe enough to take mine to 100 mph.

Talking about bouncing off rev limiters, do you know if the rover has a rev limiter I think we had the same engine before you went all continental :-)

limpabit 4th July 2014 19:20

I know MEMS has boost cut to stop over boosting (which can be bypassed).

Think it has a rev limiter built in. ECU's usually do. I know I can set mine in the aftermarket one. So would have thought it would be built in.

As for yours, get it down to TD to get it set up.

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