supercharged 1275 home brew. anybody fancy a blown minor?

Post by **superchargedfool** » Mon Feb 11, 2008 1:41 pm

Good for you being patient and not thrashing it just yet, takes some self will that does.

its got very little to do with self will, I need to now try and earn my living for at least half the day and not just pratt about with my own car all day

Post by **jonathon** » Mon Feb 11, 2008 7:47 pm

Regarding, ram/turbulance effect have a look at Abingdon Parts and their 'Cyclone Fuel Saver' Tel No 0121 544 4444. Not too sure if this is any good for you.
Do you think you might encounter heat problem having the supercharger above the exhaust, V Max Scart are mounting theirs on the opposite side where its naturally cooler on one of our customers engines. Had you thought of an intercooler, especially considering its positioning.

Post by **superchargedfool** » Mon Feb 11, 2008 11:08 pm

I have just looked at vmax scart website and they look as though they are mounting it on the exhaust side still. I know vmax scart have produced many 1275 mini's with supercharger on the hot side blowing straight into the engine with upwards of 120 bhp. I am not looking for pub bragg power figures so i will be happy with whatever i get. But it feels quick already!

Intercooler would be something i would consider but not on this first attempt at diy supercharging. Suck through carb through charger and straight into engine is simple. but if you want to do it properly you need intercooler or chargecooler and blow through carb. much more aggro but maybe next time and on a higher theoretical budget. I am trying to build this all in for £2k including 5 speed discs and susp in a tidy solid car.

Post by **dunketh** » Tue Feb 12, 2008 9:30 am

I am trying to build this all in for £2k including 5 speed discs and susp in a tidy solid car.

Good luck! I'd have already spent that getting as far as you've already got!
I guess it helps being able to fab your own parts.

Any ideas what its going to be like on fuel consumption?
I'd guess it depends on how heavy your foot is but could it be driven 'economically' if needed?

Post by **jonathon** » Tue Feb 12, 2008 9:40 am

They do indeed mount the supercharger exhaust side, but that's mainly due to space and keeping the bodywork looking original. Just thought with the opportunity to mount on the colder side might have been beneficial. Not a criticism of your work but just using what's available in terms of space to make the job easier/more efficient.
I agree over 100bhp will make a quick Minor and V Max claim some impressive figures on only mildly modified motors.
You will do extremely well to do the conversion for 2K, good luck.

Post by **superchargedfool** » Tue Feb 12, 2008 11:01 am

have just used car a bit more and seems to be all good, well nearly.

clutch slips sometimes. car has a five speed sierra box using ford drive plate and moggy pressure plate and bearing. I am obviously going to have to convert to all ford clutch, is this much of a problem?

she seems to go very well. bogs down a bit if you try to put your foot straigh to the floor after gentle driving but otherwise it runs lovely.

If you feed the throttle in the first time its ok and when you change gear just floor it and it off you go.

have spoken to my local rolling road as to if they had any experience of forced induction, carbed a series and they said NO. but they will have a cheap look to see where the fueling is and perhaps play with the timing.

I am totally serious about this being built for £2k including the tidy car. I might when its finished and I have had my fun then build another one with intercooler and a blow through 40 dcoe. Perhaps aiming to see 150 horses at £3k.

the blow through 40 is easy to do cos you just buy a pair of carbs for an old esprit turbo and use one.

I always seem to have the next idea growing when I get close to finishing the current one.

Post by **aussiemike** » Tue Feb 12, 2008 2:27 pm

Hmmm if you do manage to find a pair of carbs frm an esprit and want ot sell one to fund the project please let me know!!
Really admire your attitude towards this project. Made it yourself and have kept it really simple and veyr effective!!! (unlike myine!)
cheers, michael.

oh yeh.....youtube definately.

Post by **superchargedfool** » Tue Feb 12, 2008 5:38 pm

youtube will come when sorted, maybe next week (he said with a strained smile on face).

Have been playing with mixture today a bit more and it goes lovely, BUT with every bit of good news seems to come bad: clutch slips when really get going.

Oil leak is proving hard to find as well but I suspect it is rear main.

other than the fact that tomorrow engine will be back out to sort these two LITTLE problems its going really well.

point of post is this: advice is needed about sierra 5 speed conversion that uses moggy pressure plate and moggy release bearing. It is obvious to me it doesn't like 100 ponies through it, so I obviously need more clamping pressure from the pressure plate. This means fitting sierra pressure plate and release bearing. What is involved in doing this?????????? Anybody done it already?

cheers for now and thanks to all those who have said encouraging things, I am enjoying squeezing this project into little gaps in my days between what pays the bills.

Post by **jonathon** » Tue Feb 12, 2008 7:38 pm

PM sent

Post by **superchargedfool** » Wed Feb 13, 2008 7:19 pm

well, I thought about taking engine out today and decided that maybe a few miles under gentle driving as fault finding miles would be a good idea.

Did a 15 mile drive this morning with the rocker cover vent plumbed to atmo via a catch tank and the oil leak has gone completely. I dont understand why but I am happy.

previously I had rocker breather and timing chain cover breather connected togethor and going to inlet side of carb. now have timing chain cover breather going to carb and rocker cover breather to atmo and all seams happy.

clutch isn't such a slippy issue if you up change without using it. i will sort clutch out after a few hundred miles but for now a few running in miles.

drive this morning was quick but sensible untill nearing home when i let it have full chat in 3rd and then fourth. the sat nav said the speed was 106mph (private road obviously).

was really impressed. it pulled well and with minimal problems. timing is at 12 deg before and fueling is by trial and error but is definitely close. scary thing was silly speed came up in fourth and it was still pulling (not hard obviously) but it would have gone again in 5th but instead I changed up and slowed down.

I had decided on a sensible rev limit of 5K but it sounds so happy and pulls so well that went out of the window and am changing at what sounds happy, seems to be 6K.

am probably going to buy an uprated pressure plate from jlh tomorrow and live with the nasty release bearing senario, it works after all.

cheers for now folks.

Post by **bmcecosse** » Wed Feb 13, 2008 7:35 pm

Well done - it was probably the oil leak that has done for your clutch. If there is now no leak - then it may even 'heal up' enough to be useable with reasonable care. It's possible the new piston rings have bedded in (although I don't see any evidence of you 'running in' gently!) and so there is now less fumes for the breather to cope with.

Post by **Spag** » Thu Feb 14, 2008 7:27 am

Did you have a plan for setting the timing ?

Main thing to worry about is max advance & pinking, as effects of timing at lower rpm/load are somewhat less destructive...

The A series dizzy typically reaches max advance at about 3.5 - 4k doesn't it ?

I would be thinking that 28deg at 4k should be reasonably safe, then when the fueling is confirmed as not too lean so it melts the pistons, start adding a degree at a time until it just starts to pink under load, then back off a deg or 2 to be safe...

Just idle thoughts

Post by **superchargedfool** » Thu Feb 14, 2008 8:57 am

as for running it in, I will admit to getting a little carried away, but who wouldn't. To be fair though some people advocate semi hard running in and if you are familiar with engines you know when they are unhappy without looking at gauges, you just know.

Timing will pe played with on the rollers, but it isn't pinking, it isn't fuel smoking and its going well so must be damn close. But we all know the last 20% of an engines power comes from the fine tuning I hope it works out like that for me!!!

I am still thinking about fitting o2 sensor into one of the primary's and having an afr gauge so I can keep an eye on it while driving.

Post by **superchargedfool** » Fri Feb 15, 2008 9:47 am

well car has done about 100 miles in last 24 hours and all seems reasonable.

am going to experiment with dashpot springs and where to plumb in advance pipe. It seems to drive beautiful on very light throttle and go well at same time, if you floor it when its not expecting it, it bogs down. feed the throttle in and it goes superbly. clutch still not happy though (slips as power builds, never mind it makes you change up.

photo is taken today outside work because I went home in it last night to do some miles.

Post by **superchargedfool** » Mon Feb 18, 2008 3:57 pm

advice sought as to where I should be plumbing in the advance and retard pipe on forced induction set up. any informed comments? I have got it where it would have originaly been which is on carb after the throttle butterfly, does this suit forced induction? I don't know myself.

Post by **Spag** » Mon Feb 18, 2008 4:41 pm

There's a thought...

Are you attempting to retard the ignition timing on boost ?

Or are you just trying to use the 'normal' vac advance to advance timing on low throttle etc ?

Post by **superchargedfool** » Mon Feb 18, 2008 5:16 pm

looking for vac advance as normal.

Post by **Spag** » Tue Feb 19, 2008 8:43 am

Engine side of the carb then.

Post by **superchargedfool** » Sat Feb 23, 2008 1:00 pm

well I have done about 300 miles this week in the moggy with no problems at all. Clutch is sort of ok if you drive it with care.

My train of thought at the mo is why not fit a hydraulic concentric, no need for arm and pivot problems.

has anyone tried fitting a calm unit into a birmingham bell housing then?

Have now fitted a 12 blow through electric fan in front of the rad and moved rad back 15mm which has made the top hose a bit happier.

cheers for now

Post by **superchargedfool** » Thu Feb 28, 2008 12:10 pm

well I had to wrap the inlet to stop it freezing shame cos it looked lovely in mowog green.

I know the debumpered look is cool but bumpers are usefull, but I couldn't resist, no exhaust either it comes out passenger side.

number plate is only 4.5 inches from floor but god it looks good down there. cibies are a bit over the top maybe but I think it looks well hard and tasty.

the outside look is just about finished. The inside is going to be painted floors, cage, period black vinyl buckets, harnesses and ally panelling.

I have now done about 1000 miles and no real problems, performance is seriously good unlike the fuel economy.

I am trying to persuade stuart gurr of vmax fame to file me a best guess needle based on a BER to get fueling a bit closer.

The electric fan is a 12 inch pacet that I picked up for £30 off ebay and it fits really well, and the rad now sits a bit closer to the engine on slotted holes which has improved the top rad hose angle.

I am still on course to be on budget but only just, at the mo it stands me at about £1750 all in.
ttfn