maybe if you turbo the 1100 you should be able to get what your after.
go for it, i love 1100's. your not silly for doing it, i see where your coming from wanting to get the most out of small bore motors etc, theres plenty of people like you, tuning 850's through to 1275's.

_________________
real men race downhill - keiichi tsuchiya

I'm really not sure I see what the big deal is here, what am I missing?

GR got 89 at the crank at 5500rpm from a worked over 998. Keith Calver got an average of 7.5 (10 in some places) bhp more out of a 1098 than a 998 (at the wheels) with the same mods.

So why is 60-70 at the wheels from a 1098 that unthinkable? Great little engine, perfect for khana/autocross. I say go for it. "Because I can" is always a good enough reason

Hey , aim at 70 hp at the wheels , even if you fall a bit short of it you'll still have a brilliant little motor and a lot of satisfaction in that you've sorted/planned it out yourself .

_________________

I'm building my 1100 motor - from bottom up 3.44 diff, balanced crank rods and pistons , lightened and balance flywheel, over bored 0.100" flat top pistons, double row timing chain, RE13 cam, 295 head- modded slightly, twin HS2 carbies, electronic modded dizzy and and I've had two Mini builders ( Paul G and GR) tell me I'll get 80-85 out of it. - fingers crossed

_________________
David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Way too many people confuse themselves with flywheel HP & road wheel HP

Way too many converstions about HP are miss-interpreted because of this

drive train losses, wheel alignment, different tyres & pressures & wind resistance & weight , climate & temperatures & & & & etc etc etc all effect the end result (Edit--> in real life driving situations)

Years ago in New Zealand they use to have hundreds of minis buzzing around the race tracks & with classes for everyone. It really is amazing what can be done to a small bore engine with all the goodies inside & built the right way,,, BUT!!! there is a point where the average road driven mini isn`t really a road mini anymore. A rough lumpy barking Av Gas breathing race engine doesn`t belong on the road, but can surely & easilly have more than 60hp at the wheels. Just not something you would want to drive your mum to the shops & back in.

Please understand the difference between flywheel HP,,, & HP at the road wheels.

& also the difference between a road engine & a race engine.

_________________
No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

I didn't see any confusion of it above?

A race prepped 850 (there's still a couple about) will go about 70-75 at the fly, but as Mat says is not something you'd want to be cruising around the supermarket carpark in without launching yourself through somebodies BM'er

From memory GR said his 90bhp (at the fly) 998 would be perfectly drivable, but it was going to be sold. Anyone know where it ended up?

My 1030cc motor gets 40hp at the wheels and should get more once the new head and extractors are fitted...

I always thought an over bore of 0.60+ was the maximum for an 1100

I've heard of someone getting 1220cc out of their 1100 but that was 0.120" over.

_________________
"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

If we just say that gearbox, wheels and all that jazz losses 30% power (this is a funny bit, I've read through many mini rolling road days, here is Aus, and in UK in miniworld, (miniworld go on a standard 25% loss but this is silly, it's just to make the mini sound more powerful on paper than they are, no proof in flywheel figures))

Some cars seem to lost around 40%....that sems weird, either the engine dyno over reads, or the chassis dyno under reads, or it's genuinely not a fast mini. But most I think would sit on 30% more a road car.

If so, that means I have 107hp at the flywheel, at 4900rpm (dyno operator didn't rev it higher, weird.)

(with 30% losses, 95hp atws would be 135hp at the fly, right on...let's test this later.)

I know this fly vs wheels is just a continuing arguement...... So I think in this thread from here on, only speak of power atws, as that what's the originator of the thread asked for, 70hp at the wheels - a big ask for an 1100, watch out for reliability issues which may arise??

A 998 in Adelaide got 58hp atws. His IS a racing motor with much money spent.

_________________
1964 Morris 850, 1330 Supercharged - 81.8hp atws.
1975 Leyland Mini S 1100S powered - Nice and reliable.
1977 Leyland Mini LS - Project LS-T

On the contrary I think keeping both the 'flywheel' and 'wheels' figures in the mix highlights a few interesting annomolies, far beyond the differences between dynos.

There's also the issue of 'crank' being same as 'at the flywheel'. Correct me if I'm wrong but don't some engine dyno's measure with and some without a flywheel? THAT"s going to make a big difference.

Slinkey, using the 30% figure (lines up with what I've been told) that's about 82 at the flywheel, which sounds about the same as the mini7 guys here run (approx).

If GR's 998 ran over 90 at the crank the more I think about it the more I think the descrepency is not between 'wheels' and 'fly' but 'crank' and 'fly'....

If flywheel to wheels is 30%, then what's crank to wheels????

I think the 0.060" figure was because that was the max size pistons made. GR has 0.100" being made for 1100 and the 0.120" has to be offset bored

_________________
David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Yes, 70 at the treads is possible. It will be a very lumpy motor and things will more than likely break.
My 1132 was running like crap (I learned the hard way) and made 45hp at the MRC dyno day... its making lots more now.

The compression in mine is low (9.4ish) running 10.5 or 11:1 would see huge gain in HP but would also see me blowing head gaskets to smitherines more likely.

You CAN build a 998 or 1100 with 100+ HP which should see around 70hp at the wheels.

If you go forced induction... its alot easier to achieve obviously.

I say stick to the 1100 (or 998 will make same HP with maybe less torque) and have fun.

My recipe for a 1100 100HP beast would start with:
1100 +.080"
RE282
RE7 intake mani
Supapipes
Very, very worked head (202 or similar)
oversize valves
10.5:1 compression
HS6 (or HIF44)
Lots of tweaks to it too...
Rockers need to have enough lift too (.350" abouts) but NOT 1.5 rockers... 1.3 only.

Pete.

_________________

Click here for the Turbo Conversion Thread!

Interesting points you raise SMAC.

I was unaware that the GR smallbore was crank not flywheel.

If all his engines truly are crank. Then, the 40% loses I've seen from the Ausmini Dyno days is probably correct.

Also, engine dynos are usually done without alternator and fan correct? How much effect does this have, if any? I imagine that the alternator is minimal due to not being underload (no electricals running appart from igntion) and fan, well it's just a fan. But it still raises the question of engine vs chassis dyno.

_________________
1964 Morris 850, 1330 Supercharged - 81.8hp atws.
1975 Leyland Mini S 1100S powered - Nice and reliable.
1977 Leyland Mini LS - Project LS-T

It all depends what you want to measure.
Rolling roads are just that... rolling roads that measure HP at the treads/roller (not technically 'at the wheels' since we are looking at symantecs )

Crank HP is to tell you what the engine has... total without the acessories that may reduce a little.
Im not sure how much difference it would make, but it does add up...

All I know is that I love how much power my NA 1132 has... how much HP doesnt really mean anything to anyone except ON dyno's...

Its possible to have less HP but have a quicker car than the guy next to you I guess so its all relative.

Pete.

_________________

Click here for the Turbo Conversion Thread!