supercharged 1275 home brew. anybody fancy a blown minor?

Post by **aussiemike** » Sat Apr 05, 2008 12:27 am

where did you get the seats from???
bugger to hear it spitting the gasket too. Why not fit a copper one?

Post by **superchargedfool** » Sat Apr 05, 2008 9:30 am

seats are cheapies from midland wheels at £150 a pair. Very small but my rear just fits.

Interior is not intended to be fantastic, it is just cheap and purposefull.

Painted floor is noisy but strangely cool.

New gasket is on its a copper one.

Strangely metro turbo ran standard gasket and the only uprated ones I can find are ringed types that envolve block machining. Who knows I might do it to the next engine after this one dies!

Should be back on road this afternoon. I've got to earn my living before I can get back on to it.

Post by **aussiemike** » Sat Apr 05, 2008 2:42 pm

cool! really like the seats, might get oe for mine.
cheers, michael.

Post by **theminorsite** » Sat Apr 05, 2008 5:34 pm

superchargedfool wrote:Should be back on road this afternoon. I've got to earn my living before I can get back on to it.

Well if you've got it running again today I might chance me arm and beg a ride when I come over tomorrow

Post by **bmcecosse** » Sat Apr 05, 2008 9:50 pm

I really do think you will need the special (and expensive!) turbo gasket. And i would go back to the 5 psi for now.

Post by **superchargedfool** » Sun Apr 06, 2008 4:21 pm

have already gone back to 5psi and have fitted a copper payen gasket, sad thing is the gasket will have to go in the bin tomorrow when I take the head and sump off so I can re-ring no1 cos I have dropped a ring. 160psi on 2,3&4 but 50psi on no 1.

I am quite surprised to have done a ring in 3 miles, I was quite confident that the weak link would be the headgasket well before any more serious damage, but you live and learn.

Should have it stripped monday and order bits for tuesday and then put togethor tuesday ready for a pub meet tuesday night 65 miles from home. Does that sound ambitious?

Heres hoping.

Post by **theminorsite** » Sun Apr 06, 2008 4:26 pm

superchargedfool wrote:Should have it stripped monday and order bits for tuesday and then put togethor tuesday ready for a pub meet tuesday night 65 miles from home. Does that sound ambitious?

Ummmm, more than a little bit, yes! Nice to meet you today

Post by **bmcecosse** » Sun Apr 06, 2008 5:47 pm

Not at all - if you have the parts it's a straightforward repair - unless the piston is smashed up !

Post by **minor_hickup** » Sun Apr 06, 2008 8:07 pm

Didn't the turbo trav drop a piston ring? I wonder if this is a weak point in forced induction

Post by **bmcecosse** » Sun Apr 06, 2008 9:58 pm

Of course it is! Hence the v high cost of the fancy special pistons which can take the strain!

Post by **superchargedfool** » Sun Apr 06, 2008 10:00 pm

frustration is that with 5psi on 1293 most I can aim for is 120bhp giving good performance and torque at cheapo money, ie a £300 engine build.

with 7 to 8 psi 140bhp is achievable giving seriously quick acceleration and torque like a very strong 2.0 ltr. But to run 7 to 8 psi I am thinking that a wire ringed headgasket and forged pistons are needed, which make a £1000 engine build.

with 10 psi 150bhp is easy I think but very short lifespan between rebuilds and over £1000 engine build cost.

Frustration is that I can afford it but I am trying to see what can be done without throwing a cheque book at it! I don't want to go away from an A series but I can feel a Zetec coming on.

£1600 for a throttle body and ecu, £200 for a donor vehicle and 170bhp easy. Performance enough to embarass anything unless it realises what you have under the bonnet before you put your foot down.

I will try 6psi this week after re ringing no1 and might try water injection to calm detonation.

Am I a masochist or just daft? I don't know.

I know modern donor isn't difficult but I just feel throwing a cheque book or using a modern donor just isn't in keeping with the spirit of a moggy.
Cool quick moggies should have an A series rattling away at the sharp end.

I might try harder with the forced induction A series and keep a look out for another solid moggy to try a zetec on and have a pair, one keeping with tradition and the other just being a bit quicker but not in keeping.

I am not anti non A series minors, I just respect quick A series minors more!

Post by **superchargedfool** » Mon Apr 07, 2008 12:47 pm

Well no 1 piston is out and very dead. New piston is available but not till wednesday so thats my plan of going to my show tuesday night out of the window.

Good news is that the bore is unmarked.

I am more happy about the bore than I am unhappy about the show.

Post by **superchargedfool** » Mon Apr 07, 2008 2:46 pm

I am contemplating a set of quality pistons instead of 1 replacement piston.

Any suggestions as to which brand is good for a series with forced induction?

Ratbag · Post by **Ratbag** » Mon Apr 07, 2008 4:22 pm

I can't comment on piston brands, but as you're changing them you should seriously consider CR (if you haven't already).
If you want to develop power using high boost pressures, you need to have room to put all that charge to keep combustion pressures down. Having lower piston tops may be easier than chambering the head, and certainly more reliable than multiple head gaskets / spacers.

Post by **bigginger** » Mon Apr 07, 2008 4:31 pm

From memory, he's already using low compression pistons
a

Ratbag · Post by **Ratbag** » Mon Apr 07, 2008 4:33 pm

OK - but if you're increasing boost then you need to be decreasing CR even more.

Post by **superchargedfool** » Tue Apr 08, 2008 7:39 pm

I have come to the conclusion that I could spend £500 on having block machined to take group a ringed head gasket and fit forged pistons, run 10psi and have about 140 plus bhp. BUT how long would the bottom end last? Answer: not long.

I am going to stick at 5psi with standard low comp cast pistons. It went well like that anyway.

Reason for my sensibleness is that I came across a cheap nissan 200sx today that I fancy that as a donor for a wolf in sheeps clothing moggy. Imagine 180bph, lsd, dump valve, jap reliability in a moggy. Hmm

I am now looking for another good shell of any type or might possibly do it to this one later in the year after having my fun with the supercharger.

Post by **bmcecosse** » Tue Apr 08, 2008 8:44 pm

I wouldn'y worry too much about the head gasket - but real quality pistons are going to essential - and CR down about 7:1 ! Probably need to machine the tops of the pistons - and also open up the combustion chambers as much as possible - probably remove the beak completely and just have 'bath tub' chambers. Not so good on squish - but the s/charger will mix up the air/fuel anyway!

Post by **minor_hickup** » Fri Apr 11, 2008 5:01 pm

Just a thought...

Perhaps running 10psi boost, or even 7psi is a little optimistic on an forced induction system with out an intercooler. Perhaps it would be better to blow through a metro turbo carb and use an intercooler. I believe this is what Picky used and found a renault 5 cooler to be a good size.

Post by **superchargedfool** » Tue Apr 22, 2008 1:32 pm

Well I have just driven it to its MOT with 5psi of boost and hepolite dished standard pistons.

Sensibleness has ruled. 100 plus bhp and good torque is enough for now.

Engine seems lovely with four new pistons again. The clutch is a delight now I am running the mondeo concentric release bearing. And the period racer style interior is quite suited tothe nature of the car. The roll cage has made the car feel much more taught at the back end.

I have now fitted the tele front shocks that came with the car although I didn't like the idea of hacking the bit of inner wing out for the bracket so I made my own top mounts that weld to the inner wing, I realise the inner wing isn't strong enough for this but where they mount is where the inner wing is attached to the box section so is strong enough. Looks neat anyway!

Hopefully MOT by end of day and start using it again.