20 replies to this topic

[MINIMADMATT1275]

the time has come for me to refurbish a engine i bought a few months back
I have got a few questions

What sort of power am i going to be looking at ie hp torque 1/4 miles top speed ect out of this spec engine

1330
AE 21251 +60 dished top pistons
lightened con rods
wedged nitriled and shot peened crank
stage 4 11 stud 12G940 head with rimflow 35 mm inlet, 32mm exhaust valves
1.5 roller tip rockers
hiff 44 carb with pipercross filter
and probrably a kent 286 cam
mg metro electronic ignition and copper cored silicone ht leads
the gear box and gear ratio's are standard
with a lightened and ballanced flywheel

the cam needs replacing and i was going to put a kent 286 cam in it, anyone got any oppinions on anything better because i want it to be brisk but useable on the road

As it is being rebuilt im going to put new
piston rings
big end bearings
mains bearings
cam bearings
oil pump
cam followers
camshaft
cam chain & tentioner
clutch (will a standard one do with that power)
not sure what do do with the gear box, i may change the final drives any ideas?
Is there anything else that you would change whilst it was in bits?

cheers again in advance!
Matt

[Paul Wiginton]

Make sure you get the cylinders deglazed and measured.
You might get 100bhp out of that

Paul

[MINIMADMATT1275]

yeah will de-deglaze the bores, they arnt worn but like you say get the glaze taken off so the rings bed in properly.
id be happy if it made that kind of power, the bloke i bought it of said he thought it was about 110 bhp but i took that with a pinch of salt because it was a ebay engine.

[MINIMADMATT1275]

Anyone?

[Jordie]

About 90-105 bhp at the flywheel.

Wheel power depends on box etc? straight cut drops?

1/4 mile etc times is too hard to guess, depends on the weight, driver ability, traction, final drive ratio etc

It should be a very rapid engine, the 286 is a good choice for that engine. Make sure you dont get bind on the valve springs when using the 286 with 1.5 ratio rockers. It will be very quick.

Tuktuk's 1330 with 286 is rapid, faster then some of the 1380s we've seen.

Jordie

[Jordie]

Pre verto clutch? go for a new back plate, orange diaphram and a fast road/turbo clutch plate. that will handle it fine.

[philc]

cam wise look at sw5, i have a crane vp3c which has a longer duration than a 286. Have a look at this link, gives you loads of ideas for cams. You want one with as little overlap as possible. also depends on what carb you are using and manifold and exhaust and compression ratio. Make sure this is inline with your cam. I notice that you are looking at replacing your piston rings, spend a little extra and get some that overlap, these helps in keeping compression.

www.edhodson.com/personal/miniresto/Mini%20Cams.xls

Edited by Jordie, 25 November 2008 - 03:38 PM.
fixed link

[MINIMADMATT1275]

Im probrably going to be running a standard A+ gearbox unless i can get my hands on a better one for a good price.
What sort of power will i be loosing through the standard drops?
Am currently running standardish weight, driver ability o.k. (but hey im biased) lol running 165 falken tyres on a 6x12 alloy, standard final drive bu im am thinking about swaping it for a longer final drive. do you think it will pull a longer one as i hate hearing it sitting at 4,000 rpm or something silly on the motorway (I dont like to rev cars too high it scares me lol), but for arguments sake what do you think it will be safe to rev to?
Yeah will look out for the valve springs binding it was alright though, do you think its worth fitting new springs?
yeah i did a search and found that the 286 was about right for this engine, as some people seem to think that the sw5 may be a bit mild on a 1330 want it to be brisk but not unuseable on the road what does the crane vp3c drive like as i havnt heard of them before.
Sorry but what do you mean by piston rings that overlap? surly i will just have to fit the rings that are the right ones for my pistons, somebody said somthing to me about stepped rings, and that you should fit these to engines when rebuliding when they have not been reboredbecause i cant find any anywhere, do they exist?
cheers again

[Jordie]

Depends what FD ratio you have now. a 3.44 is common, but this will give you 4000rpm ish at 70mph in 4th. a 3.1 or 2.9 would give lower rpms at 70mph, but you would also be slightly slower on acceleration. Its a trade off, you need to find a happy medium.

Engine like that if fitted with a centre main strap, should be rev to 6000rpm ok.

[MINIMADMATT1275]

Yeah its no good having blistering acceleration and be flat out at 70! what i dont want to do is fit a longer fd and the acceleration to be woefully slow as i i do mainly country road driving but now and again i need to go on a motorway.
It hasnt currently got a centre mainstrap fitted, do they make much difference has anyone ever split a standard one, or is it the fact that they deflect? do you think it really needs one or are they a bit gimmicky? I will probrably see how much they will charge to fit one when i get my new cam bearings done sorry for all the questions i just dont want to build this engine up to be a expensive dog! if ya know what i mean,
thanks again
matt

[Jordie]

Mixed opinions from what I hear. I fitted one as a matter of course on the N/A engines ive built. Havent fitted one to a turbo engine as the revs dont go high anyway.

I think the MPI's run a 2.9 final drive. The MPI engine in my friends mini limo is certainly quick, yet the revs arent massively high at top end speeds. It shifts to say its a limo

[MINIMADMATT1275]

Yeah i think i will probrably get one fited when the block goes to jonspeed for new cam bearings. actually has anyone had any experiance of them whilst were on the topic, or suggest anyone local to cov that does a good job on machining and stuff, that isnt too expensive?
hmmm 2.9 final drive, i suppose thats about right because wernt the sportspack about 90 bhp to? just a bit worried about the fd because i know its quite a big jump between 2nd and 3rd already a longer fd will make that worse, wont it?
cheers

[Jordie]

90bhp....your kidding right.

The later SPI and MPI cars were around 50-65bhp i believe. Because of the ECU people say once modified they are limited to around 90bhp if the ECU is kept/used.

Not sure, the gear ratios on a mini are quite good in my opinion and with the right cam, it will pull like a rocket anyway. Id be going for a 286 or similar, which will kick in so to speak around 1800rpm onwards.

[philc]

In respect of my cam vp3c this comes in around 2200 and finishes around 7500, if you look at the link i have sent you it will give you the info you need, below is my recent rr figures, the power and torque lines are smooth and is still delivering a good level of power at 6500k before it drops due to my rev limiter



in respect of jonspeed, i have no opinion, tho those i know who have used them have not been impressed, i also think you are going a little far to have your block machined and could find a good machinest alot closer, i am sure if you ask around someone can advise.
In respect of ring over lap, most piston rings have a small gap allowing them to expand and contract, this allows compression to escape, I suppose not huge amounts but some, asware overlaped rings do not have this gap thus you do not loose compression.
You would get away with a good standard gearbox, though i would suggest you purchasing a 4 pin diff

Edited by philc, 25 November 2008 - 08:08 PM.

[MINIMADMATT1275]

Oh i thought the sportspack were qute high power, but maybe not then!
I find on my 998 that the ratio's between 3rd and 4th are a bit far apart but that may just be because its pretty low on power.
Yeah true enough, i suppose if you are giving it the beans its not going to come off cam between changes so it shouldnt struggle.
when it "comes on cam" is it a noticeable jolt of power or is it progressive?
Philc what spec is your engine? is it a large bore?
Jonspeed isnt that far away fro me, only nuneaton and i thought they were mini specialists but i think you are better going to somewhere that somebody has recomended rather than just picked out of the phonebook. does anyone know anywhere that sells these piston rings with overlap that are sutiable with A.E pistons.
yeah will prob get a x pin diff

cheers again.