3 replies to this topic

[pogie]

I’ve been going though a few ideas for an engine build and have pretty much sorted out what I am going to do, but I also want to have the gearbox overhauled at the same time. The engine will be to a 1380 fast road spec similar to the one built in the Bill Sollis DVD and as it will spend most of it's life on the road with only the odd track day I want to keep it pretty civilized so straight cuts won’t be fitted.

The thing is that when driving on previous track days I have noticed that the box in my 1990 RSP Cooper has a huge gap between 3rd and 4th and the drop in revs is really noticeable as the standard engine takes ages to drag itself back up the rev range to where the power is made.

I have read somewhere that the old 1300GT remote change boxes had much closer gear ratios and I was wondering if the gears are compatible with a rod change box? I wouldn't have to worry about sourcing one as my old 1380 engine was built using a 1300GT lump and I still have the box lurking in the corner of the garage so I’m hoping it would just be a case of swapping over the relevant parts as the refurb is being done.

I realise that with the new engine and the increase torque, the drop in revs will not be so much of a problem, but as the box is coming apart anyway it would be the ideal time to fit the 1300GT gears. What do you think?

[Big_Adam]

Just change the final drive man, it's as simple as that. Guessworks will even do you a box and you pick the final drive you want.

[icklemini]

to be honest the 1380 with a sw5 will be nice and torquey so you'll be fine with the A+ setup.. (imho).

depends exactly what you want to do with it.. but a fat torque curve and a close ratio box isnt something to desire really :s but depends what you want to do with it..

TTFN,
Dave

Edited by icklemini, 18 September 2007 - 09:13 PM.

[pogie]

Thanks for the replies.

Just change the final drive man, it's as simple as that. Guessworks will even do you a box and you pick the final drive you want.

What! A far too simple solution. You expect me to miss out on the chance to use my bloke-ish tendencies to make a job far more complicated than it really is. You disgust me.

I have seen quite a few posts as to the good quality of GWs work, I will probably end up talking to him when I am ready to have the gearbox done.

to be honest the 1380 with a sw5 will be nice and torquey so you'll be fine with the A+ setup.. (imho).

depends exactly what you want to do with it.. but a fat torque curve and a close ratio box isnt something to desire really :s but depends what you want to do with it..

TTFN,
Dave

As you said, I expect the problem of the gap between 3rd and 4th to be a lot less pronounced with the 1380 with it's extra power and torque. I just thought that whilst the box is apart for the referb I may as well use parts that I have to hand to optimise the gearing. It may be that with the close ratios of the 1300 GT box I could get away with a taller final drive than I could with the standard A+ box.

I also have a Cooper remote, SC/CR with Salibury LCD, box sitting on the shelf next to the 1300GT box, but that's a different story.