Escort 4 speed or sierra 5 speed in an escort?

[esky_fan]

I currently have a 5 speed sierra In my Mk2 Escort ghia with a mildly modified engine(port n polish, extractors, twin webbers, and a road/race grind cam), I have found the sierra box not really suited to my car and was wondering what would be the best idea change to a 4 speed or chnage the gears inside the box?

[outback_ute]

Welcome to the Forums esky_fan!

In what way is the 5sp not suited to the car? Ratios too tall? Too widely spaced? You could get away with a lower diff ratio than standard, with the overdrive 5th gear.

[Engine Guy]

If you find the gearing 'too tall' for your car you would be better off trying a 4 speed box.

Chaning ratio's inside a Ford 5 speed box is not easy... you need a special 5th gear puller in order to dismantle the box (although I have dismantled some without a puller) however, even if you manage to overcome 5th gear removal - finding alternative gear ratios is going to be even harder!!.

See if you can find a 'good' Transit 5 speed gearbox, ratios are usually a lot closer in those.

Cheers
Engine Guy

[esky_fan]

IM finding first way to short, im having to change first gear stright away. i have a 4.1 diff in it now. ive never had a 4 speed escort always been autos or 5 speed. ive been looking at the gear ratios bewteen the 4 and 5 speed and they seem very similar. with changing the gears im not to sure if having a first gear around 2.4 2.5 is good. will my car have enough torgue to pull it?

[shepv8]

I always thought that the sierra 5 speed had the exact same ratios as the escorts 4 speed with the 5 gear being the overdrive.....

[esky_fan]

escort is 3.65, 2.154,1.425,1
Sierra is 3.65, 1.917,1.37,1 and 0.82

[V8falcons]

What do you use the car for???why dont you change the diff ratio,back to a 3.9,or 3.54. alot easier than doing a gearbox

I have a 2ltr with a sierra 5 speed with a 3.9 and it all works well togeather,apart from the planetarys about to explode.

oh and by the way there a re a few different ratios with the type 9 gearbox as well.

[Fev]

I'm 99% sure the Sierra T9 5spd has the same first 4 ratios, whereas the other Sierra box, the T5 from the Cossies was definately different.

[T3man]

There is no benefit changing to a 4-speed as the ratios are identical. You either change the diff back to a 3.54 if you have a 2.0L or 3.7 if you have a 1600. Otherwise put a Supra 5-speed alloy box conversion (Dellow Auto in Sydney or Castlemaine Rods in Vic) and use the close ratio option which has IIRC about 3:1 first gear and 0.85 OD.

[esky_fan]

I use the car for fast road use and a bit of draging? i was thinking of going up to a 4.4 and changing first gear to 2.9

[T3man]

You've lost me now ... 4.4 diff and 2.9 first gear is basically the same as the standard diff with the gearbox you have now ...

[Puzzlescort]

I use a 4.9 diff with a 2.5 first - it still takes a while to wind up down the strip, I end up in top real quick!

I would try changing the diff ratio first to a 3.9 or 3.77, then I would start worrying about gearbox - even then I would be looking at gear sets that are available for the T9 box instead of going back to a 4 speed

[esky_fan]

At the moment im going with a 4.1 diff and a 2.9 first and a cam that start making good power fromm 4000 i also have 215/50/13 tires. would having a 4.4 diff make much diffrenece to the car and in which way

[T3man]

I can't imagine any reason to change from 4.1 to 4.4 - the difference in gearing is 0.7% - simply not worth any expense to achieve. I wouldn't even spend my time doing such a swap even if I had both diffs sitting on the shelf for free.

You just need to do some math to work out what you want with your gearing. If you are building an outright drag car you want to be reaching redline in fourth as soon after crossing the line as you can manage. Until you've actually done some runs to determine roughly what your terminal speed will be you won't know exactly what gearing is best for you.

If you do track work you might find the need for different rear end (taller gearing than a drag car) to suit whatever speed you will achieve in various corners and on various straights - you'll never get it perfect anyhow but it's fun trying.

[T3man]

Originally Posted by esky_fan

escort is 3.65, 2.154,1.425,1
Sierra is 3.65, 1.917,1.37,1 and 0.82

Just harking back to this - so your motor is actually a 1300? Going by those ratios - if you say they are the standard 4-speed ratios for your car, then it must be. Because all 1600 and 2000 gearboxes had the same intermediate ratios as the Type 9 which you say is in it now.

I've just checked some available ratios to suit your car with a 4.1 diff and retaining the Type 9 gearbox - cost UK about 750 pound sterling. You'd be looking at $2k landed here I reckon. Is the car worth that much?

BTW, I did some quick calcs for you and based roughly on what you've said you'd like to do with the car the best gear set I can find is ...

2.38
1.62
1.23
1.0
0.84

...from this site ... http://www.rwdmotorsport.com/tran-x-...t/prod_33.html

I don't know if much stuff like this for Type 9s is available in Australia as I have always taken the cheap and easy way out and used Supra alloy boxes in my Capri and Escorts.

Anyhow good luck with your project.

[esky_fan]

The motor is a 1600 . I dont really know if the car is worth it but ive already sunk ******** loads of money into and i might as well get the best out of i can.

[whooligan]

I've heard that the sierra boxes aren't the best behind a crossflow, but changing to a 4spd isn't really going to solve your problem. As someone else suggested, you might be best off swapping to a celica/supra 5spd instead if the diff ratio swapping doesn't help your cause......Oh, and I just happen to have a Celica 5spd in my shed for sale. :hihi:

[T3man]

woohoo - so do I. Let the bidding begin! LOL.