turbo 850?
Turbo Mini Forums

I have a 78' 850 and in the future would like to keep the oringinal engine, i have learnt alot from the forums about forced induction and this is the direction i think i will go - BUT

It seems there always a bit of talk about 850 turbos but never any proof that someone has done it and with good or bad results?? I understand theres not as many about which is some of the reason i want to do it, but theres just not that much info for me to look at as other engines.

So if any one has done it / knows somone who has, could you just give me some details - problems, power output anything

cheers guys.

Mike

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

There are a few 998 turbos on here, but no 850s that I can recollect.

I'm sure it has been done before, but specifics examples escape me at present.

I think that lack of decent pistons is the limiting factor.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

thats what im saying we all think there are some out there but cant seem to actually see one runing. lol

isnt a 998 just a stroked 848 - so cant u use 998 pistons?

mike

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

I didn't do it but what I have done is a file to help me calculate outputs and the results have been agreed by knowledgeable people on here.

I assume a 850 can do 85 bananas without putting too much money in the pistons.
But you will need to find an appropriate turbo sizewise.

I believe the biggest issue with a 850 is that due to its capacity, for the same amount of money, you get less bananas.

So at some point you have the choice to buy forged pistons for your 850 to up the boost in the 15 psi region, or you can use a 998 at 10 psi and it will do better ...

When you enter the 998 section, you're told "this is the shadow, the setup is not straightforward" (at least, was), I feel 850 is even more difficult to deal with and will keep on this way due to the money vs bananas equation ...

Rusty by nature

The 998 is a longer stroke and larger bore.

I think that standard 998 pistons will sit about 4mm down the bore and give 895cc.

EDIT: Got capacity wrong.

Edited by Paul S on 17th Jan, 2010.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

ah yes your right, so if i bored my 850 out to the 998 bore and stuck with 998 pistons it would be 948 - not realy what iwant to do but if you cant get good enough pistons its an option. Cheers paul.

mike

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

Advantage - you make some good points, my main reasons for wanting to go 850 is the facts the engine thats supose to go in my car and not many people have done it. But youu are very right about the cost vs power is never gone go my way.

To be honest 85 would be great to start with with an 850 -pretty mental. Could i have a copy of this calculator?? no wories if not just might be helpfull.


Has anyone considered supercharging, im more toward turbo because it can be cheaper and cheaper to run as this is my daily driver!

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

Well, if it is your daily drive the you need to think about the logistics of the conversion.

You will need the engine out of the car for a while, depending on what you have done, if you want to make any internal modifications. Most of us take years to build our turbo engines and get them on the road.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

yea that sorted - i meant it WILL be my daily and i currently have a stage 1 1275 in there at the moment :) so i can get it on the road and built an engine then - thats the plan, odds are it will change soon

Also how have people insurance gone up when sticking a turbo on?

mine has doubled just sticking a 1275 in the car.

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

depends on your age,

I'm 32 and my 998 mayfair is 150 quid a year with direct line (must swap it to hic)

my mk1 7 port turbo is 200 a year with HIC

when i changed engines, my insurance came down by 250quid , it went from a 998 stage 1 kit + modded head to a std metro turbo engine up to 125bhp ( age 18-19)


on topic, im sure ive seen in the mini mags over the last 4 years or so with a few supercharged 850s what pistons have they used?
i dunno but maybe searches on various forums would find them..

Edited by Brett on 17th Jan, 2010.

Yes i moved to the darkside

Instagram @jdm_brett

Insurance companys are soo stupid, i asume because its a standard engine you put in they think thats its safer or something?? got that wrong, good for youu i suppose

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

Yes i moved to the darkside

Instagram @jdm_brett

true :)

back on topic, any more facts, figures, pics, ideas etc etc :)

cheers, Mike

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

I'm not a believer in doing something just because no-one else has; as a sole reason anyway.

As said above the pistons are the stocking point. But if you can fit 998 pistons then do that. With the head on no-one will know so just say it's an 850, 895cc is pretty colse anyway.

Froma turbo point of view I'd be looking at the GT15.

I'd say 90bhp at 10psi should be achievable.

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

www.twin-turbo.co.uk

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

The GT15 comes in two basic sizes GT1544 and GT1548. Do a search on this forum for more info.

Have a look at www.crturbos.co.uk and search for gt1544, they were fitted to lots of cars. they are very similat to the T2 on paper.

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

www.twin-turbo.co.uk

awsome - lots of cars on that list, and quite new also might be able to get a goodun from the scrappy, all seem to be deisel cars, i assume they would be that same as from a petrol car?? i will do some more searching, cheers.

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

Yes lots of cars. The thing to watch out for is the letter following the number. Ihave a feeling that 'V' means it's a VNT which wold be useless. But 'S' is ok as far as I know.

If anyone knows what the letters mean it would be useful.

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

www.twin-turbo.co.uk

That KKK KP35 off the 1.4TDCi Fez looked like a good selection for an 850.

Do a search for a recent thread "diesel turbos"

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

yes i read somethi9ng about them being a vane type?? i think iv already looked at that thread and it looks a good size. After loking at the list im gona try and get one from a mulitipla or somthing that asnt been ragged - is this good logic??

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

Turbocharging an 850 is all well and good, and certainly possible. But if you spend the same amount of time, effort, money, on a 1275, you will end up with more power at less boost pressure. After all, the reason most people modify engines is to get max power increase for their money. Something to consider anyway.

Good point Tom, but if you use that logic (as smart as it is) why are there so many 998 turbos (this does not include Wil_h and other hill climbers, i know you need the smaller engine to get into the lower class or something :) )?

I can only gather because thats the only engine they had or they wanted to have something a bit different??

but in the end i will be spending alot of money Turboing an 850 hwere the same amount of money will get me tons more power. I could always do and if im not happy with the results at least i can reuse all the turbo stuff on a bigger engine, and ill still have a pretty good backup enigine - right? The only 'Loss' i would make is the machining costs.

Mike

1978 - 850 - 1275cc MG Spec engine - Turbo build soon....

To be honest your reasoning that the car is registered 850 so you wan't to keep it that way works for me. Me and Wil like 998s for all sorts of reasons. we have never modified a 1275 engine so will stick with what we know.

http://www.twin-turbo.co.uk
http://www.hillclimbandsprint.co.uk/default.asp

A man without a project is like a like a woman without a shopping list.

Dont the 850 blocks have cranks like clothes hangers and only have a single cam bearing? Or are these the issues to overcome?

In boost we trust