My classic is currently in for a full 6 speed conversion.

I've told myself the cost isn't so bad as on my 70 MPH cruise home, due to it being 6 gears instead of 5 the revs will be lower at the same speed, therefore using less fuel.

Or not?

 

I would think with the cost of the conversion taken into account it will be a long way off before you see any benefit if you do at all !

I'm sure somebody will chip in with some more technical stuff.

Regards
Neil

 

Yes with a 6 speed you should be using less revs at 70, but as Neil said, you would be waiting for years to get your money back, same with LPG unless your doing loads of miles or keeping car for years no point

 

I didn't think for one minute I'd get my money back just be nice to notice a few extra miles per tank.

 

Cookie, my widetrack STI sits at about 3k rpm on the motorway at 70 MPH, are you having the car remapped for the new gearbox? thay might help also

What you'll be saving from not smoking will will help you save some more

 

Lol, slipped today, back off it in the morning.

Mapped for a gearbox? What are you smoking?

 

Different loads on the engine due to new ratios *cough*

 

The 6 speed weight over the 5 speed will be like carrying a passenger full time, so you'll definitely not benifit

 

I thought there was about 20kg in it?


Looks like my reasoning to the wife why I've just spent £2k on £500 car, is coming undone.

 

secrets safe with us

 

You could be right, all I know from helping a mech once is that the 5 speed in comparison is like lifting a sack of spuds, where as the 6 speed was three of us sweating like **** trying to locate the splines They are one hefty pieces of kit

 

To paraphrase Jurassic Park:

- Is it heavy?

- Yeah.

- Then it's expensive - put it back.

 

Well it looks like iam the sad one than.

It would seem having spoken to mr Google that 1.2.3.4.5 are shorter in the 6 speed than the 5 speed but top gear in both are similar ratios. So in summary, not going to make much difference.

I would not be surprised if mr googles best friend pops up to tell me iam wrong but if I had given it anymore of my time, I would have had to punch myself in the face.

 

well its nearly 2am so should get a googlefied pasted awnser

 

Sorry bud but the reason STI's have worse mpg than WRX's is the gear ratios, so expect mpg to go down not up.

So a lose, lose situation, must say I admire your thought process though, just think of all the money you'll save by not having to change your box again.

 

since i have had my 6 speed i notice i am revving less when cruising on the motorway.
i still prefer the 5 speed but needed the stronger box.

 

As above, the box is heavier and most ratios are shorter than the 5 speed. Good sell to the wife but a flat put lie!

 

disagree with Lpg
back to school or are You still there kid

 

tell her having the number 6 on gear lever removes material, hence weight saving!
if shes blonde you may get away with it.

 

 

I'm going to need to buy a large turbo now, to console me.

I really thought I'd improve MPG, it had NOTHING to do with being able to take huge power now.

 

Or not.

 

I'm almost certain that when I swapped from a classic 5-speed to a 04 STi 6-speed, the final ratios were the same in 6th as they had been in 5th.

The new 5th and fourth were lower than they had been.

As for mpg, since I went from 300 to 400+ at the same time, I can't say I've noticed any difference

 

400 now there's a nice number.

 

lmao, look out, the mrs is on his case about how much he's spending,,,,,,,,, hahahaha

 

Quote of the day right there

 

In 6th I'm using about 700rpm less than with my 5 speed so it's got to save fuel

 

^ Yep 2800rpm at 70 in sixth on my classic, saving money all day long ... in theory... until the next corner

 

70mph in 5th, on my 5 speed, is 3K rpm.

Your saving nowt.

 

Does it not depend on which 6speed your using eg UK sti jdm sti blob or hawkeye etc
I heard 6speed s are about 30 kg heavier

Also depend s which gear box you had before if your coming from a 5 speed type r or RA to a
6 speed then yep you will be doing lower revs at the.same speed at a slight cost of weight etc