Engine Spec Help

[greggy50]

Hello

I currently own a classic mini 1000 and wanted to give it a bit more pace

Basically it is currently running a 998cc engine standard apart from a bigger HS4 Carb from a 1275 on a minisport inlet that I had properly jetted and then a straight through 2.5" system that is probably sapping a lot of power...

Anyway I just want it to be a bit nippier and wondered the best way to go about this was!

The engine itself seems a bit tired it is on about 75,000 miles and doesn't really pull the car along that well at all (probably due to an exhaust) so think it would be better to get a new engine either way.

I already have a 12g295 head with double vale springs in good condition sat in the garage and believe this is the basis of a decent 998? It would be nice to see 60bhp as should be around 40bhp stock?

My budget is around £500 (ish) with regards to the gearbox mine is sweet so just really need to get a 998 engine in decent condition then see what other parts I need

Thanks

[greggy50]

May add would rather build engine up and then swap them over ideally...

Would I be better selling the 12g295 head and getting a 1275 presume I could get more power then for my £5/600 ish?

[greggy50]

Hello Cooperman

I have decided to up the budget somewhat and build my own engine...

Anyway I have just purchased the A Series book by David Vizzard and plan to build a 1330 engine

I will sell my 12g295 head and keep the current 1000 lump in whilst I build up my new engine. To be honest the engine itself may not be that bad it will still pull 85 ish if required (normally do more like 55) I think it is just I am used to a 230hp GTI Golf!

What is a decent 12g295 head worth as a couple of people are after it it has never been skimmed and doesn't have any cracks after taking the valves out?

Engine Spec wise thinking of the below (copied from yourself on the miniforums):-

For a 1330 giving c.100 bhp you might like to consider the following:
Hepolite 21253 pistons - make sure you do a trial-build and deck the block to bring the pistons right to the top
Kent 286 cam
A big valve head, fully gas-flowed. Comp Ratio around 10.7:1
Twin HS4 carbs on a good alloy inlet manifold
Light-weight pre-Verto flywheel and clutch
LCB ex. manifold with a 1.75" int. dia. exhaust system - RC40 or Maniflow
Aldon 'Red' distributor, or a 'Megajolt'
Vernier timing gears
Metro Turbo oil pump

[greggy50]

Have come up with the following list of parts what stuff am I missing out of interest?

And what gear ratio would be best my wheels are 12 x 6 t

1330 Potential Engine Build
Pistons – Hepolite 21253 pistons = £180
http://www.minisport.com/87-524111-00set-slipper-p...
Camshaft – Kent 286 Cam = £220
http://www.minispares.com/Product.aspx?pid=36201
Engine Gasket Set = £10
http://www.minisport.com/geg206-engine-gasket-set-...
Head Gasket Set = £10
http://www.minisport.com/geg1140c-head-gasket-set-...
Metro Turbo Oil Pump = £50
http://www.retrominisltd.co.uk/index.php?main_page...
New Clutch Kit = £50
http://www.minisport.com/hk8855-3-piece-clutch-kit...
Vernier Timing Gear = £80
http://www.minisport.com/c-ajj3327-mini-sport-ligh...
Engine Re-Bore = £100
Block Re-Machine (after checking TDC) = £40
Crank Re-Grind = £50
Gearbox (Guessworks) = £400
Refurbished + New baulk ring + X-Pin Diff + Pick-up pipe
Twin - Carbs = £150
Donor 1275 = £175 ish
Headwork = £250?
Total = £1,765

Thanks a lot and sorry for the length of these two posts!

[greggy50]

Cooperman said:

I have a 286 cam in my Cooper 'S' but that is a rally car with a SC CR gearbox and a 3.9:1 FDR.
Never would I ever fit one to a road car. The best road cam for a 1330 cc Mini is the Kent 266 (or MG Metro - they are very similar). For the road you need low to mid-range torque unless you intend keeping it revving at over 5000 rpm most of the time. Remember, a 286 gives peak power at 6400 rpm. You really don't want to be driving at those revs on the road all the time. Below about 4000 rpm the 266 will give better overall performance.

Is they something inbetween like say a SW5? Or a 276?

The car is only used for a thrash at the weekends really and is by no means a daily drive

Also what is a good way of checking the health of an engine?

Think I may be being a little harsh on my 998 it pulls up to about an indicated 85 given the room and sure the xhaust is sapping a lot of power so tempted to fit the 12g295 head I have sat in the garage in the mean time

Thanks

[greggy50]

I am on about my possible 1330 build here not my 998!

Sorry my plan was to check if my 998 was healthy and stick the 12g295 head on if it was

Then build up a 1330 engine using the Vizard book I have ordered so cam spec would be for that engine

[greggy50]

Okay thanks turbo is an option as well

First step is going to get uni out the way but looking for a 1275 in need of rebuild atm and getting my 12g295 checked then sold as Dad who normally hates cara has decided would like to help me build an engine which is fantastic of him

[greggy50]

Right well I have just purchased the following

A+ Block
Kent 276 Cam - done 2,000 miles
Forged Cooper Rockers
Omega 73.5mm Pistons with 11cc dish + standard rods - pistons are great condition and new rings
1275 Head
Down Draught Twin-Choke Webber on Manifold and ITG filter
Gearbox with standard Gearset
Few other bits to assemble

For £300 does this seem a good price?

I am guessing now need to source other parts main of these will be a crank how much should I be looking to pay for a decent one?

Also need to get (please add)
Clutch + Flywheel - any recommendations?
Gaskets
Timing Gear
Metro Turbo Oil Pump
Then presume need new bearings for the crank etc... - any specific ones needed?

Oh and finally will need help with the compression ratio nearer the time as the head will need skimming an stuff to bring it all in line

Also what should I be looking to do with the gearbox?

Do I need to go straight cut as heard that is bloody loud?

Or can I just get a centre oil pickup pipe + x pin diff?

Power wise not going mental guessing will be around 80 - 90hp? if that helps with regards to the box specification

Oh and finally ignore budget stuff mentioned earlier now secured a graduate job

Thanks a lot

[greggy50]

Managed to blow the bottom end on my 998 the other day so engine needs to go in sooner than I hoped

Basically have ended up with the following

Low Millage 1275 Engine
Rebuilt Gearbox with 3.2 Final Drive Centre Oil Pickup (8k miles ago)
Forged Cooper S Rockers
MG Metro Cam
MG Metro Head with a bit of work done
HIF 44 Carb

Gave £350 for the above have stripped it down all seems good just adding some new gaskets oil pump etc... then going to plonk it in the car oh and I know I fitted the heatshield the wrong way round on the carb ha!





I did want to do more to the engine and make it a 1330 etc... but drove the car this came out of and it pulls very strongly and to be honest now by 998 has blown want to get this sorted and in for the summer then may look at supercharging it over the winter...