120 replies to this topic

[Jammy]

the stiffness of the clutch peda

Surely that would come with every powerful engine due to the rating the clutch would need to cope with the power?

Thank god it didn't have an LSD or I'd have put it in a hedge

Wouldn't a Quaife ATB LSD have sorted this out at least a bit?

[Sprocket]

I am still confused as to why fittind an LSD would put it into a hedge or is every one getting confused with a locked diff.

I would have thought keeping a rally car out of the hedge is the first priority and they use an LSD

[Oldskoolbaby]

I love the idea of having a 200+bhp mini (gradually trying to build one) but having that much power sometimes plays second fiddle to a less powerfull motor. I completly understand the attraction of having 200bhp as you must feel unbeatable when you have it in a mini.

However, if you want speed, watch the Extreme Mini Dvd. Theres a 115bhp 1380 that beats much, MUCH more powerful cars around the track. A good friend of mine owns a 1293 S and he says it can beat one of the local turbo minis off the lights and that has a load of Avonbar bits on. By the time the turbo has found enough grip to actually move, the 100bhp S is already 1/4 of a mile down the road
Id just say, ask yourself what you really need. If your planning on blitzing it through tight country roads, a 200bhp will be near on uncontrolable at full chat. But if your after something to p155 cars off on the motorways, then I cant think of anything better than a tall diff and a shead load of torque and power :grin: .

[DaveCoxon]

LOL at the last answer...There are sooooo many dog's of turbo minis out there, that are basically nothing more than MG metro turbo transplants with a coat of paint.
Also - if your cornerweights are all to *male chicken*, forget putting any power down - turbo or nat-asp...

No 1380 of the same weight as my mini would be in the lead after even 10mph - let alone even 1/8th of a mile :wink:




As regards the clutch - yes, a double-grey is heavy. But excessivly IMO, to the point that your leg muscles are working so hard, you're losing sesnitivity - and launching a turbo on the dragstrip definately needs sensitivity. I'm designing a whole new clutch/flyweel assy at the moment, that will have a torque capacity of at least 250lb ft with an organic, but have the release-force of an Orange. Well, that's the theory - basically, if it's less than the single-grey (with more torque capacity), I'll be happy.

And the LSD - well, maybe a quaife would help - but i doubt it. An 'open' diff can be corrected as it relies on full traction across both wheels - once traction is 'lost', power transfer to the loaded wheel ceases. Nice and safe. This is when something like a salsbury would be very dangerous to the un-trained, as it tries driving with one wheel, and will have you off the road before you know it.
Rally cars (minis) don't have an LSD to keep out of the hedge, but to aid traction when going forwards...


LSD's definately need well set-up suspension - especially cornerweights and spring rates. Don't do this, and it'll bite you for sure.

[Sprocket]

Dave ever thought about using the grey diaphragm but change the master cylinder for a slightly smaller cylinder??? will there be enough pedal travel to stop the clutch dragging??? just a thought

[DaveCoxon]

There won't be enough pedal travel - you could shorten the pushrod to the master cyl slightly to raise the pedal....
BUT
My biggest gripe with the grey - and even more so the double Grey- is the loads it throws at the thrust washers.
I've just had my flywheel on my press with a (freshly calibrated) force-meter. As you push the cover over-centre (just disengaging) the load peaks at over 4000 newtons (or 0.4tons for the non-educated)!

That is wayyy too much axial load on those thrust washers...

[Wil_h]

a nat asp 998 with 200bhp, this is surely *******, even with a 16v head.

Just think, 3 litre F1 engines were only producing 800bhp a few years ago which is a similar cc:bhp ratio, and they were reving to 16000rpm!!

Wil

[AlexF2003]

a nat asp 998 with 200bhp, this is surely *******, even with a 16v head.

Just think, 3 litre F1 engines were only producing 800bhp a few years ago which is a similar cc:bhp ratio, and they were reving to 16000rpm!!

Wil

You need a 73mm + bore to get the four valves in I was told by KAD....


Alex

[minimole]

i am sure i saw on the kad website they said the did a smaller version of the 16v head. Maybe i have just gone nuts and started to see things?

Edit: Just had a look at the kad website they do a smaller valve version and a larger valve version but both are designed for 1275 +

[Sprocket]

970S engine, overbore +20 =998 :cheese: I wish my bank manager would let me

Edit: or is that +40 :nugget:

Edited by Mini Sprocket, 11 January 2006 - 07:07 PM.

[AlexF2003]

WOuld that take it to a 73mm bore?

I dont know old A-series.

Alex

[Sprocket]

WOuld that take it to a 73mm bore?

I dont know old A-series.

Alex

no, more like 72mm

[AlexF2003]

that might be enough....

would be cool, if a touch pointless

Alex

[Sprocket]

Add a turbo and I cant see there being a problem reaching 200bhp as long as you use a lot of boost

[Sprocket]

oh and another thing, the 970s bored out is as near a square engine as you will get without the exotic cranks.

998, its a small engine thing. How much power can you get from a small engine, just like people trying to get as much power as possible from a 1275, it has nothing to do with final power figures but rather how far power can go on each engine