Club 80-90 Forums

Looking at a gearbox ratio table as I would Like to change my van to 5 speed, and the ratio gearbox for the van is the same ratio as the gearbox I have except one is high revving and one is low revving....what's the difference please??? ( except the obvious one revs higher than the other!!!haha. I mean in performance wise..) Cheers Gareth

you need to know both box codes.

use the wiki and brickyard to find this.

google gear speed calculator , enter the details and you will get the revs at given speeds.

performance will depend how you drive it and the state of your engine

High Billy thanks for advice I have the codes so I guess I will look for calculator, I don't mean performance as getting pinned to ya seat when ya give it a right.foot full, I just mean how does each gearbox differ in the way it works and why one is high revving and why one is low....and if it matters if you change a high revving box with a low revving box with the same ratios.....cheers

you cannot change high /low reving with the same ratios!

high reving means the engine is revving lots at say 60 mph ie 4500rpm , whilst a low revving means its only doing say 3000rpm at 60mph.

the gears inside th box are different so as to speed up/ slow down the engine in each gear


the max torque of any engine is at a certain amount of revs so ideally you need this at a good point during acceleration .
also your engine will only pull so much , so for example in theory letting your engine rev at 1000rpm and be doing 70mph would be great but is impossible due to the lack of torque at 1000rpm to push the van at that speed

Hhhmmmmmm very confused...haha, so although the ratio numbers are the same on the ratio table because one is high and one low then the ratios are not nesassarily the same..? I never did get how a gearbox works, getting brain burnout...lol

ratio is how many turns the first gear has compared to the one it is turning.

so ratio numbers will not be the same ,

so all the gear inside the box , thats 1,2,3,4 and reverse CANNOT have the same ratios otherwise all the gears will be the same and you will not drive any different no matter which gear you select

what ratio table are you using?

This table....http://rjes.com/html/gearbox_types.html" onclick="window.open(this.href);return false;

I see what ya saying now....it's not rocket science is it...lol

I have also missed a complete chunk of what I want to achieve out, which would make clearer if told it......
My thoughts...my van is 4speed at the moment, but I have a 5speed petrol box with diesel bell housing (low revving) but the 5speed standard box with the same ratio which fits mine is a high revving box...does this matter....think that's a bit clearer....haha

nothing makes sense

petrol /diesel / 4 speed / 5 speed , they all fit some are worse than others you must know the codes

some 4 speeds are better than 5 speeds and vic versa

petrol / diesel also

it all goes by code.assuming the internals are un modified.

a standard 1.9 petrol box can be the same as a td jx box inside ratios ect

a 1.6d box will give good acceleration but about 55mph is top speed
an aap 2.1 box slower acceleration but 80mph no problem - but remember a 1.6 non turbo will not work on an aap 2.1 box due to lack of power

4speed..... APF
Gearbox I have...8e with diesel bell housing
Standard gearbox.....ABR

I think I am making it complicated in my own head.

apf -( 4000rpm - 66.04 mph)(3000rpm- 50mph) in 4th

8e -(4000rpm - 77.85 mph)(3000rpm -58.4 mph) in 5th

abr -(4000rpm-68.79mph)(3000rpm -51.6 mph) in 5th

depending on where the max torque of your engine is (rpm) depends how well it accelerates in each gear

in top gear at low revs there is usually less torque hence dosent accelerate fast and slows on hills
drop it say to 3rd gear , up the revs to more torque (same mph speed) and it will go up hills better

any clearer?

Yes a little clearer now Billy...thanks ever so much for your info and patience....
Your info has helped alot as I am not looking to go faster just quiet down the engine when cruising at around 60mph so I think it might just work....

That makes sense to me too, thanks Billy, that is why with my 1y I don't get to go any faster but I do get to go uphill without slowing down.

ABF is for a 1.6 n/a diesel which will struggle to pull the 8E fifth, you'll be using 4th a lot, just stay stock imho, unless you've fitted a 1Y

Aidan wrote:ABF is for a 1.6 n/a diesel which will struggle to pull the 8E fifth, you'll be using 4th a lot, just stay stock imho, unless you've fitted a 1Y

Hi Aidan the code on my box may be different then but hard to see due to numbers faded on side, I have a 1700 diesel with 4 speed, not looking to go any faster really just like the revs to drop slightly when cruising at 55-60 as it's a bit noisy...

with regards to noise have you got

the rear rubber floor mat
engine bay sound proofing ( foam padding)
engine undertray (with sound proofing)

all part of the factory sound proofing by vw!

stick some slightly larger tyres on the rear , see how you get on , not quite the same as changing the box , but much simpler!