New to turbos please help
Turbo Mini Forums

Hi all, I am new to turbos and I need some advice.
I have just got a top mount turbo setup that was apparently on a 1000 running 5lbs.
I have a fully rebuilt 1100 20 over standers pistons at 9:1 compression ratio with Cooper s spec valves ported head 276 cam centre main strap and electronic dizzy.
My question is can I safely put a turbo on my engine?
How much boost can I run?
If I use a head spacer what size and how much boost will be safe with standard pistons?
I will add a pic so you can see what I have thanks in advance for your advice.

Attachments:

3.58mb

1.38mb

That setup looks pretty poor!

It’s suck through rather than blow through. I would not put it on. You’re putting fuel through the turbo.

You could get away with a reasonable amount of boost at 9:1 with a safer setup.

Edited by jonny f on 28th Jun, 2018.

It is a bit of an odd setup. But it was done successfully by Turbotechnics back in the day.

Some info on that setup here http://www.turbominis.co.uk/forums/index.p...tid=355170&fr=0

With your engine running 5 or 7psi should be no problem.

The cam is not ideal, and the dizzy will need changing for one with less advance, or you could just fix the advance to something sensible.

It's not going to set the world alight, but should make a nice torquey motor.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

I was going to say the pistons are a bit shite, but as its at +20 they are probably better than the std ones,

echoing what will sayd, the cam is a bit OTT especially on a small bore, but it wouldnt be hard to swap out as you have the tappet chests,

I dont like the head spacers, but as its low boost it'll get the job done, in fact you might get away with just 2 headgaskets?

I guess at 5-7 psi you could probably expect 80-90 hp

That manifold is a bit crap isn’t it?
Agree with the others. Suck thru sucks, and 9:1 is fine to have lots of fun, but plan on an inter cooler (which you can’t with a suck thru setup).

So I should sell it and build my own can you recommend what I should do. Turbo size, cam, ignition etc is 120hp out of the question. Thanks for your advice.

Depend on your budget.

With your CR you could get away with leaving the engine. Pistons/Cam are limiting as suggested above though.

A simple well proven spec:
GT15 or 17 depending on target hp
Fusion fabrications manifolds/plenum
hif44 turbo carb (or convert non turbo)
Intercooler (looks like you are in aus so i would say its a must do)
Megajolt ignition

Probably worth changing the cam to something more mild. kc 266, NA metro, avonbar ph2.
Set of decent cast pistons of forged if you can afford it.

Take aloof at the “topped” posts in each of the forums, there are many to bring you up to speed.
There is nothing really complicated about boosing the a-series, but blow thru is going to need more parts you don’t have (Electric fuel pump, rising rate regulator, blow-thru carb, plenum) but it means when you want more - it’s there!

That suck thru looks lousy, but it may be a quick and easy way to boost, but that turbo may be knackerd and need a rebuild. I recall suck- thru turbos need a different seal material on compressor side than normal turbos, or the life is reduced significantly; maybe that’s ok for your limited use though?

if your looking for 120 hp those pistons may become an issue, but with a decent piston it will be doable with an intercooler.

as a guide plenty opf people have done road 998's with around 100hp, and wil_h had a 998 hillclimb car putting out about 150hp, ( with a 7 port head he got to roughly 180hp)

Thanks looks like I run this engine the way it is and build a BMW twin cam turbo 1275 and do it right.