24 replies to this topic

[Awlred Drives a Quant]

How many RPM is the ideal shift point for a 998 with standard Gearbox (I think 3.05 Final Diff but not sure) running with a leaded head copensating with Valvemaster Plus.

Cheers

Sorry for being a n00b

[Leonard]

about 5,500rpm. you start losing power and torque after this

[Big_Adam]

What Mr Leonard said.

although I normally shift at 5000rpm.

[TOMMO0302]

Im not sure if that is 'ideal'......sure in terms of getting max power etc from each gear im sure it is, but isnt that a little high in terms of wear!?

[Sprocket]

Its not power that determines shift point, its torque. That does not mean that the peak torque rpm is right either.

[1984mini25]

And how many “suspected” miles has this wonderful 998 done?

[miniboo]

is there such a diff as a 3.05?

[fikus01]

my bog std old 998 was setup on the rollers and pulled hapily til 6200 max power was at 5950 but bringing the revs over this kept me at the top of the power band for longer!! rather than shifting early and having to wait for the power to arrive with the higher revs!!

the old rover mini manual that comes with the car tells you that under normal driving conditions you should keep the revs between 2000 and 5000 rpm!! full acfceleration isnt normal driving conditions, most rolling roads will test power to 6000rpm unless you state otherwise!! a std 998 bottom end is perfectly happy coping upto 7000rpm before you have to worry about big end bolts!! 1098's arent as rev happy tho but the longer strokd does make them torquey!! stil mine is happy to pull to 6000rpm with a kent 256 cam!!

[Sammy D]

With my 1098 I usually like to shift at around 2,500. 3000 is pushing it, the gearbox is just too noisey! I've had 90mph at about 5000.

[fikus01]

2500 - 3000 rpm!! shes only making half power at that point!! serously if it goes bang at 5000rpm it was guna go bang neway!! and a std bottom end on a 1098 is good for 6500 trust me mine is std and does it regularly! if there is no power there then dont push it. i know minis are noisy but they do have some revs in them!!

especially 970 and 1071 lumps:D try 10'000rpm

[AlexM]

2500 - 3000 rpm!! shes only making half power at that point!! serously if it goes bang at 5000rpm it was guna go bang neway!! and a std bottom end on a 1098 is good for 6500 trust me mine is std and does it regularly! if there is no power there then dont push it. i know minis are noisy but they do have some revs in them!!

especially 970 and 1071 lumps:D try 10'000rpm

You make a good point there, you should'nt drive because your worried your car will go bang, otherwise you wont enjoy it. Now ive finally sorted out all (most) of my minis running problems im going to start really driving it again, and i can take roundabouts at speed again now ive fixed the CV joint which has been clicking for the last 3K.

[biggav]

jeeeez..... I change at 8500!!!!! and she gets to 7500 in fourth!!!!

[fikus01]

1071 and 970 use a 1275 cc bore and are short stroked for the cc required!! they dont have much torque but by heck when they get up to revs they sound good much nicer to your gearbox with that little amount of torque!!

im thinking of trying one with a 74mm bore and 7 port head for future developments!! shud nearly make 1300cc!! but will rev like a bike!!

[Jimmyarm]

Why do you go so far past the peak power when you shift ?

IIRC mine hits top BHP at 5290 and torque is about 3700 (will check that when I get back!). I always shift just after peak BHP and it seems to work pretty well

When you do the shifting action, is the aim to shift so that the revs drop down above or below where the peak torque is produced ?

[fikus01]

my old 998's peak power was at higher rpm, and i went over it so that when i did a gearchange the revs didnt drop too low!! from 6000rpm my gearbox takes me to 4000rpm!! and thats where the engine started pulling!! anything lower you had to wait til i got to 4000rpm before it would start to go!!

and peak power on my 1098 really is over 6000rpm!! trust me if ther was no power up thre i wudnt take her there!! im well aware some chav style racers have to wait for the max revs or rev limiter before a gear change but thats not what i do!! jsut want to get max power and then go!!

by all rights my racer shud pull to nearly 7000rpm!! and its only got a 276 cam!!