14 replies to this topic

[Minigman]

I’m considering rebuilding my small bore engine instead of doing the ‘normal’ 1275. I’ve been reading up about mini 7 1000cc engines that rev to 9000rpm and produce 100bhp.

Apparently they use a standard 1275 Cooper cam 6648 so I was wondering why they rev so high as max bhp is achieved at 5700rpm on that cam.

The engines appear to be +0.020” forged and a steel crank is used. The head is a standard 12G240 with a single choked Weber 40.

How do they make 100bhp?

My current 998 is making nearly 60 and is quite modified so not sure how they create that much more.

Edited by Minigman, 04 June 2018 - 08:12 PM.

[phillrulz]

my 998 is making 51 at the wheels only stage one ? 

[Minigman]

It really isn’t. Sorry no offence intended.

51 at the crank would be a cracking result.

[phillrulz]

It really isn’t. Sorry no offence intended.

51 at the crank would be a cracking result.

 

https://puu.sh/Az7my.png

 

Its what the rolling road said, 3rd gear 57lb/ft, max hp around 5750 rpm  max torque 3800 ish 

unless this points you to a mod but the guy i got it from said it was stock.

does go like stink.

 

 

stock my engine should be " 40bhp @ 5000rpm    50lb ft @ 2500rpm    1982-88: Mini HLE / City E / Mayfair"

 

 

So to me thats believable increase of 11hp and 7ft/lbs .

 

Exhuast manifold, intake manifold, air filter and needle.   

 

Guy said he had never seen such a flat fuel / air ratio on any aseries engine. 

Edited by phillrulz, 04 June 2018 - 09:07 PM.

[Minigman]

I think you’ll find that’s at the fly not road wheels.

Still an impressive result for a stage 1 though. The odd 998 have made 44/45 bhp and with roughly 15-20% stage 1 gain, 51bhp would be about right.

[Shooter63]

Mini 7 engines use a regulation 649 type cam 940 type head on a pocketed block a 45 dcoe on one barrel etc and a lot of expensive parts, my friend even has an Allen steel crank ( unobtainium) that's how they make 100bhp

Shooter

[Minigman]

Only Miglias use the 649. 1293cc

[DeadSquare]

BHP figures, like official MPG figures, are always taken under the most beneficial conditions.  At the flywheel, without a water pump or generator and ideally very cold moisture laden air.

 

The figures for our late 60's Downton Mini Se7en didn't quite scrape 83 BHP from a plus 040" 848cc.

[OzOAP]

Look at www.facebook.com/ozoap.
Video of my latest mini 7 engine at 9000+ on the rolling road.
998 + 020, MG Metro 6648 cam, modified standard crankshaft.
9500+ revs, 102hp @ 8500.
We use 4.7 final drive at most circuits.
I have done road versions of '7' engines with very good results, running 3.9/4.1 diffs. They are a toy and not a daily driver.

[DeadSquare]

Look at www.facebook.com/ozoap.
Video of my latest mini 7 engine at 9000+ on the rolling road.
998 + 020, MG Metro 6648 cam, modified standard crankshaft.
9500+ revs, 102hp @ 8500.
We use 4.7 final drive at most circuits.
I have done road versions of '7' engines with very good results, running 3.9/4.1 diffs. They are a toy and not a daily driver.

 

 

Mick, do you know what BHP your Mini Se7en engine produced?

 

 

Applogy:-

 

 

Oh dear.      That was a boo boo.

 

I jumped to the conclusion that  "OzOAP"  was Mick Ozbourne  Old  Age  Pensioner.

Edited by DeadSquare, 05 June 2018 - 06:58 PM.

[Trissy B]

Look at www.facebook.com/ozoap.
Video of my latest mini 7 engine at 9000+ on the rolling road.
998 + 020, MG Metro 6648 cam, modified standard crankshaft.
9500+ revs, 102hp @ 8500.
We use 4.7 final drive at most circuits.
I have done road versions of '7' engines with very good results, running 3.9/4.1 diffs. They are a toy and not a daily driver.

 

Oz i have been following your posts on facebook and they are a cracking read. Cant believe how much effort and development go into those engines! Minigman - have a look as OAP's page as will answer your questions.

[Minigman]

Look at www.facebook.com/ozoap.
Video of my latest mini 7 engine at 9000+ on the rolling road.
998 + 020, MG Metro 6648 cam, modified standard crankshaft.
9500+ revs, 102hp @ 8500.
We use 4.7 final drive at most circuits.
I have done road versions of '7' engines with very good results, running 3.9/4.1 diffs. They are a toy and not a daily driver.

I’d be interested in the ‘road spec’ version.

Have pm’d You via FB

Edited by Minigman, 05 June 2018 - 03:00 PM.

[Minigman]

If you’re using a MG Metro cam does that pull from low down? I think of that cam as being quite tame for a race engine, great in a small bore road car though. Doesn’t it then reach max torque and bhp by high 5k rpm?

Will read your FB Page with interest. Thanks

[OzOAP]

 

This was a run to peak power. Peak torque 90lb at 5000.

We now have new spec crank fitted. No more power but 'speed of inertia' is better so gets up to peak power faster.

Edited by OzOAP, 05 June 2018 - 08:15 PM.

[MIGLIACARS]

you couldnt drive a 7 spec engine on the road it would be near impossible and awful  after 5 miles you would be wanting to scrap it.