Tuning an engine

Tuning an engine

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Discussion

anonymous-user

Original Poster:

55 months

Tuesday 3rd January 2012
quotequote all
Sorry to start two topics in one day but needs must.

My current 1275 mini engine has around 60-70bhp and realistically I'd like 100 or more.
What kind of figures can you get from a Mini 1000 engine?
What can you bore them out to and things like that as well.

And that compared to a 1275?
The plan is to buy a second short or full engine if cheap enough, build that up to a decent spec, put it in my mini and sell the engine and box out of mine (getting a S/Cut box)

The budget doesn't matter that much because its a project and its not going to be done in a month but lets say £2500 give or take.


One last thing, I'm also saving for Vegas in September so I'm considering just buying a fast road 1275cc head and these http://www.minisport.com/mini-spare-parts/info_MSL... to keep me happy for 12-18months
Can you tell me what the performance effect/increase would be like on both together please?


Sorry to go on so here is a picture of my Mini!


theshrew

6,008 posts

185 months

Tuesday 3rd January 2012
quotequote all
Im not sure of power figures tbh but im pretty sure the A series can be taken to 1380cc. There is another thread on here with a lot of peoples specs on that i read a month or so ago. Would be worth a look.

Loads of Mods can be done to a A series. 16v heads, twin carbs, cams etc etc etc. Im sure you will find loads of info on the net.

These days the engine is pretty old tbh and has its limits people have started put different engines vtecs, bike engines and i think Red tops maybe worth considering if its bhp your after.

Actually i really would love a fast road A series Mini. Just love the sound of them. Its just getting the Mrs to say yes !

Steffan

10,362 posts

229 months

Tuesday 3rd January 2012
quotequote all
I have been building, modifying, racing and tuning Minis for 50 odd years starting with a 1960 Mini 850 and progressing to the Cooper Cooper S Mini Marcos, Mini Jem and Cox GTM. Had a lifetime of fun with Minis still own five all in rebuilds or on the road. One Cooper S, One Cooper convertible with a 1900 Twin Cam injected K series conversion and various others. And two Midases and a fibreglass racer half finished.

I love them always have always will. Issigonis was a genius and a very nice man.

The best Mini Tuning experts I know of are David Vizzard and Clive Trickey.

Both have written excellent books on A series tuning. Well worth reading to give you background and a good idea of what can be done with the A series.

Getting 100 BHP out of a A series engine normally aspirated is possible but requires boring out to 1340 cc and nitrided crank etc.

One of my friend runs a racing engine rebuilding business. He has a Terrapin in currently for a complete rebuild ready for the next season. He has just built a full race spec 1340 A series engine for the Terrapin which is turning out 125BHP with an excellent power curve and delivery. He guarantees all his engines. I have no personal interest in his business I just like the quality of the work he executes.

He could rebuild an engine for significantly less than your budget giving this performance level. If you are interested PM me I will give you his numbers. The terrapin he has is worth a view in itself with the new engine it will fly! Business is based in the Black Country.

If you get half the pleasure I have had from Minis you will be happy.

Brilliant cars!

anonymous-user

Original Poster:

55 months

Tuesday 3rd January 2012
quotequote all
That £2500 isn't a budget I have now. It'd be spare money over the next 12months.
As for the vtec and twin cam stuff, I appreciate them but I want to keep my mini with a mini like engine in.

Steffan

10,362 posts

229 months

Tuesday 3rd January 2012
quotequote all
Take a look at the Vizzard books.

You will not find better A series data.

The old maximum A series size generally advised amounted to 1340cc with A40 pistons I think.

The problem is that the cylinder liners become too thin above that size. Reliability could become an issue.

Plus finding a really good A series block this long after production ceased is not easy.

You need a 1275 as the base because the cranks are better.

The A+ engine and Metro or MG 1300 might be good bets: the MG1300 12G95 head certainly would be worth a try.

I may have a MG Metro 1275 Turbo block about at home if that interests you let me know. I am not looking for a lot for it but I am away in Devon currently so it would take time to get it. As a base for tuning this is ideal it has the strengthened A series block used on the Turbo only.

Good luck whatever you decide.


theshrew

6,008 posts

185 months

Tuesday 3rd January 2012
quotequote all
Steffan - Have you ever built one with a fiberglass front end ?

I think if i do one myself id like to do this as it wont rust and would possibly give more room to work on things. They any good or a waste of time ?

Sorry to jump onto your thread mate

Steffan

10,362 posts

229 months

Tuesday 3rd January 2012
quotequote all
theshrew said:
Steffan - Have you ever built one with a fiberglass front end ?

I think if i do one myself id like to do this as it wont rust and would possibly give more room to work on things. They any good or a waste of time ?

Sorry to jump onto your thread mate
Yes I have owned several over the years.

The advantages of the fiberglass front end are limited and the downsides are considerable.

The Mini is a classic early monococque with subframes distributing the suspension loads across the shell. Removing the front end ruins the structural integrity of the front. The subframe sits outside the main steel body and the glassfibre front does nothing to replace the structural integrity.

In racing there is a slight gain in weight reduction and racing circuits have no real potholes bumps or changes of surface. On the road the car is much less secure with the front floating on any serious suspension loads.

For road use I would not consider them.

The Pimlico and other similar fiberglass Mini shell projects are dreadful to drive on the road. I have owned several and sold every one. There just is not the structural rigidity of steel and the noise and vibration levels are noticeably worse.

In short I would not recommend them.

Except possibly on the limit in racing where every pound matters.




theshrew

6,008 posts

185 months

Wednesday 4th January 2012
quotequote all
Cheers for that i kinda thought that they might not be a great idea. Acually more because i thought they might be a bad fit.

Does making a removable or flip front have the same problems or a slightly stronger / better option ? Pref a flip front as it would give less chance of damage when removing etc

anonymous-user

Original Poster:

55 months

Wednesday 4th January 2012
quotequote all
Could you try carbon fibre?

Cooperman

4,428 posts

251 months

Wednesday 4th January 2012
quotequote all
The problem with flip-fronts is that no proper structural analysis has been done and, as Steffan so rightly says, the Mini is a monocoque where the entire shell carries all the dynamic loads.
A friend of mine bought a 1.8 VTEC engined Mini and when I drove it I could almost feel the front end (carbon-fibre flip type) distorting. In fact it all felt very 'iffy' and I don't want to drive it quickly again, ever It was obvious nthat no stress analysis had been done, just a bit of stiffening by guess work, not proper engineering design.

Steffan

10,362 posts

229 months

Wednesday 4th January 2012
quotequote all
PSBuckshot said:
Could you try carbon fibre?
If you can get one, possibly. However I have never seen one.

I am aware of carbon fibre complete shells but again have not tried one.

The flip front does not lend itself to secure structural attachment.Generally attached to the inner wing/subframe mount points. Simply clipped with over centre clips to the bulkhead. Flimsy at best.

Without a lot of research, a fair bit of design and a number of rigid secure structural braces and locking attachments to marry the flip front structurally with the body of the car when closed, I doubt that replacing the integrity would be possible. If then.


Cooperman

4,428 posts

251 months

Wednesday 4th January 2012
quotequote all
I was told by a structural/stress engineer friend in the aerospace industry that the worst crash case for a flip-front Mini is the 3/4 frontal impact. With the original welded steel structure the ability to withstand such an impact is taken initially by the inner wing, outer wing and front panel, which transfers the crash loads into the opposite wing and the bulkhead. There are no point loads as the wings and panels are progressively welded. The flip-front vendors advise fitting bracing bars, but how the stresses get into and out of these bars safely is not allowed for nor are any supporting calculations done.
Would anyone fly in an aircraft which had had its primary structure modified without supporting calculations having been done? Probably not. So why would you drive a car in that condition?

Steffan

10,362 posts

229 months

Wednesday 4th January 2012
quotequote all
Cooperman said:
I was told by a structural/stress engineer friend in the aerospace industry that the worst crash case for a flip-front Mini is the 3/4 frontal impact. With the original welded steel structure the ability to withstand such an impact is taken initially by the inner wing, outer wing and front panel, which transfers the crash loads into the opposite wing and the bulkhead. There are no point loads as the wings and panels are progressively welded. The flip-front vendors advise fitting bracing bars, but how the stresses get into and out of these bars safely is not allowed for nor are any supporting calculations done.
Would anyone fly in an aircraft which had had its primary structure modified without supporting calculations having been done? Probably not. So why would you drive a car in that condition?
I entirely agree. Your aircraft analogy is most apposite. These flip fronts are a racing only item, it that.

theshrew

6,008 posts

185 months

Wednesday 4th January 2012
quotequote all
I didnt think it would be that strong but its been done for many many years on Mini's it kinda put doubt in my mind that it would be ok if you know what i mean.

Having said that its one of the things ive always wanted to do to a Mini along with having a fast one. I always ended up banging my head on the bonnet lol.

I think once you have had a Mini you never loose the bug. No matter how much they p1ss you off at times.

Cooperman

4,428 posts

251 months

Wednesday 4th January 2012
quotequote all
theshrew said:
I didnt think it would be that strong but its been done for many many years on Mini's it kinda put doubt in my mind that it would be ok if you know what i mean.

Having said that its one of the things ive always wanted to do to a Mini along with having a fast one. I always ended up banging my head on the bonnet lol.

I think once you have had a Mini you never loose the bug. No matter how much they p1ss you off at times.
A 'quick-removal' bonnet is the best answer. That way you don't lose any structural strength.

anonymous-user

Original Poster:

55 months

Thursday 5th January 2012
quotequote all
Cooperman said:
A 'quick-removal' bonnet is the best answer. That way you don't lose any structural strength.
They're never that quick hehe
Always worried about catching the paintwork.

FWDRacer

3,564 posts

225 months

Monday 9th January 2012
quotequote all
Cooperman said:
I was told by a structural/stress engineer friend in the aerospace industry that the worst crash case for a flip-front Mini is the 3/4 frontal impact. With the original welded steel structure the ability to withstand such an impact is taken initially by the inner wing, outer wing and front panel, which transfers the crash loads into the opposite wing and the bulkhead. There are no point loads as the wings and panels are progressively welded. The flip-front vendors advise fitting bracing bars, but how the stresses get into and out of these bars safely is not allowed for nor are any supporting calculations done.
Would anyone fly in an aircraft which had had its primary structure modified without supporting calculations having been done? Probably not. So why would you drive a car in that condition?
Utter rubbish. Perhaps you'd like to countenance your arguments with the circuit racing brigade. All employ a full removable front end and brace bars. Carbon/Glass fibre or steel, Trust me, these guys have done all the crash investigation work you'd ever require. hehe Front 3/4 is a particular favourite and the speeds involved are greater than most road Minis.

Are you aware that the the front subframe is intentionally weakened (drilling of longditudinal webs) by the racing guys to stop the crash loads being put into the body via the rear subframe mounting points? The energy disspiated by a normal steel outer/inner wing isn't in any way comporable.

As you aren't looking for ultimate weight saving in a car - fit a steel front end - then you get the best of both worlds. Triangulation from the bulkhead to the front leading edge of the frame is key.

An oppinion is nothing more than a wooden leg without the factual information to support it.

Vrindish

1 posts

65 months

Sunday 30th December 2018
quotequote all
Hello Stefan.im vrindish from Mauritius.i just bought a mini 1000. I would like to know if you have any concepts for mini 1000? As I will remove everything and re make it from sashi!!


Thabking you in anticipation

Vrindish

quote=Steffan]I have been building, modifying, racing and tuning Minis for 50 odd years starting with a 1960 Mini 850 and progressing to the Cooper Cooper S Mini Marcos, Mini Jem and Cox GTM. Had a lifetime of fun with Minis still own five all in rebuilds or on the road. One Cooper S, One Cooper convertible with a 1900 Twin Cam injected K series conversion and various others. And two Midases and a fibreglass racer half finished.

I love them always have always will. Issigonis was a genius and a very nice man.

The best Mini Tuning experts I know of are David Vizzard and Clive Trickey.

Both have written excellent books on A series tuning. Well worth reading to give you background and a good idea of what can be done with the A series.

Getting 100 BHP out of a A series engine normally aspirated is possible but requires boring out to 1340 cc and nitrided crank etc.

One of my friend runs a racing engine rebuilding business. He has a Terrapin in currently for a complete rebuild ready for the next season. He has just built a full race spec 1340 A series engine for the Terrapin which is turning out 125BHP with an excellent power curve and delivery. He guarantees all his engines. I have no personal interest in his business I just like the quality of the work he executes.

He could rebuild an engine for significantly less than your budget giving this performance level. If you are interested PM me I will give you his numbers. The terrapin he has is worth a view in itself with the new engine it will fly! Business is based in the Black Country.

If you get half the pleasure I have had from Minis you will be happy.

Brilliant cars!
[/quote]