486 replies to this topic

[Shifty]

I built a similar lump for Poo last year.

sw5 cam(gonna be ripped out and a 276 fitted)
Ultralight flywheel and back plate
12g 295 head
1 1/2 carb


That made 68 at the flywheel and a bit over 50 at the wheels

I'm gonna be fitting the 276, getting some new valve guides fitted and a set of MED 1.3 ration rockers to it this year.

I may possibly try a hif44 on it as well, it will at the limits of the 1 1/2" carb I think.

I'd like the crack the 55 at the wheels mark.

Good luck with yours

[danrock101]

I love hot small bores, I've been driving a 850 about and I wasn't disappointed going from a 1275 with about 75bhp to the 850

Shifty, I'd probably recommend getting some twin Hs2s instead of the hif44, you know you want to Rather than fitting 1.3.1 rockers which cost quite a bit, especially MED ones, nearly £200 I bet... they wont do anything power wise but with that £200 you could get a fair amount of work done to the head, like porting work. Would make sense while it's in having the other work done, you'd probably reach 60+ bhp at the wheels if the head work is good.

Edited by danrock101, 25 October 2010 - 01:12 PM.

[PhilipGCaldwell]

hey shifty, i was interested in the SW5 cam but i was put off as reports of people saying its too tame, was this the case for you?
small bores are the future, the price of 1275's on ebay is getting ridiculous

[danrock101]

Well I say that, my new engine is 1430cc lmao but it's the only way to get the power and torque I want without turbo, if I keep both my minis I'll build a hot small bore for my '72 daily driver, something like shifty's current spec but I'd open up the head a little, I'd keep the 1.5" carb to save fuel as it would be the daily. After driving my 850 it's certainly opened my eyes, ok it's not fast at all but it's standard 30 od bhp, I was expecting it to be painfully slow but it keeps up with traffic fine without having to floor it.

[PhilipGCaldwell]

1430 bloody hell!

[Shifty]

I hate the sw5, its a bit of a girls cam!!

From the output of my lump it does something!! You just don't know its there!!!

Thats why the 276 is going in.

I don't really want to run twins(spent many happy hrs tinkering with them on old MGs), I just think that the current carb may be a bit of a restriction.

The 295 head works well as standard its very easy to ruin them by tinkering!!

All this depends on an 850 as well, my other car Paddy is a '79 850. He's gonna be my show transport whilst Poo is being restored. So I may well pull the lump out of Poo and stick it in Paddy.

Who Knows???

[PhilipGCaldwell]

I hate the sw5, its a bit of a girls cam!!

haha!Ive heard that a few times before, well my minds made up, 276 it is!

as for the twins, well, to be honest the sight of twins under a bonnet turns me on

[danrock101]

I hate the sw5, its a bit of a girls cam!!

You just don't know its there!!!

lol like I said, I was shocked to see I had a after market cam in my engine when I striped it haha, that was with 1.5.1 rockers too

[olds_kool_lews]

So I may well pull the lump out of Poo and stick it in Paddy.

Who Knows???

what a strange and worrying thing to say! lol jokin

[james105]

cracking little build! Will be keeping an eye on this one!

Out of interest what paint did you use on your block! Looks brilliant!!

[miniman92]

Ive got a similar spec 998. 12g295 big valve ported head, s rockers, kc 276, fully lightened and balanced bottom end, med ultralight flywheel and back plate, orange clutch diaphragm, close ratio GT box with straight cut drops, hif38 carb with k and n, lumenition electronic ignition. Good choice of cam by the way

[PhilipGCaldwell]

well spent a while doing some honing tonight, got 2 bores done (i think so anyway)
got a good bit of cross hatching on the bores which is a good thing

Out of interest what paint did you use on your block! Looks brilliant!!

its heat resistant paint i got off ebay, unsure of the brand, it came in a blank tin

honing tool from machine mart


cross hatching effect



miniman92, cracking spec chap, you must be expecting 70bhp+ at fly?

[PhilipGCaldwell]

just a picture of my block and head after i finished painting it



the cylinder head is at the headshop having new unleaded exhaust valve seat inserted, recut inlet seats and new valve guides installed
I received my new unleaded 29.4mm exaust valves from minispares today so when i get the head back from the machinists i can accurately measure where i need to cut my pockets in the block in order to get the exhaust valve clearance.

[miniallsort]

looks good mate

[Jacko-lah]

I was wondering what project to do this winter and I think an 850 Version of that !!!