Mini Cooper SC

[LeeHoochie]

I have a mk1 sc and wanted to know if there is any performance reason to replace it with the mini sc? (good upgrade over stock maybe)

[Icsunonove]

Lee, have you fitted a big pulley? It does make a big difference

[LeeHoochie]

The reason for the question is Fensport do the later Levin type(increase by 12hp)

It has an HKS pulley which takes upto 10psi.

[Lauren]

don't bother with the HKS pulley, waste of time. Just go straight for the fensport pulley.

I had the setup you are talking about on a levin engine. Worked pretty well.

think it will be a lot of hassle to fit a mini SC. Would be interested in seeing it done, its question of making a bracket up I guess and sorting out pipework of course.

[LeeHoochie]

I did look at the fensport pulley 12-14psi apparently. May do that as a future mod money willing. I wanted to sort the cooling out first(intercooler, spal fan, possibly an oil cooler, some hideous air intake

Have you ever used exhaust rap, the label say 50% heat reduction in engine bay and can you use is on a stock manifold, and while im thinking of it TRD thermostats open at 70 degs is this good?

GASP......

Finished

[MartG]

I did look at the fensport pulley 12-14psi apparently. May do that as a future mod money willing. I wanted to sort the cooling out first(intercooler, spal fan, possibly an oil cooler, some hideous air intake

Mine makes about 12.5psi .

Don't bother with a fan on the intercooler - they just don't shift enough air compared to the natural flow to be worth it. Key is to get cool air to the intercooler ( i.e. air that hasn't passed over a hot engine ) Lauren did this by installing trunking from the sidescoop across the engine bay to the intercooler. I've started experimenting with one of the 'Tom's style' airscoops but as the car is on a SORN until spring I won't have any temperature data until then. TBH you'll probably only notice the extra cooling on track, so its worth fitting the pulley first and sorting extra cooling later if you find you need it. Best option of course is a charge cooler.

If/when you fit a larger pulley, don't forget to do the ABV mod ( a google search will find the details for you ) as this prevents the ECU from limiting the boost pressure to 10psi.

[AlexE]

I have a mk1 sc and wanted to know if there is any performance reason to replace it with the mini sc? (good upgrade over stock maybe)

Although the Mini supercharger is of a better/more efficient design it is still a fixed displacement supercharger. The mini supercharger is based around an Eaton M45 which has a displacement of 0.75 litres......when you consider that the Toyota SC12 has a displacement of 1.2 litres you can safely assume that there is no benifit in swapping it for the Mini one. A better bet would be the superchargers used by mercedes which are based around the Eaton M62 but again these are still not as large, displacement wise, as the toyota SC12....

[Icsunonove]

It would be difficult to fit though Alex, wouldn't it?....

[LeeHoochie]

sounds like i should be happy with what ive got, I could stick a tractor wheel to the crank and a pram wheel to the sc. could be interesting

[Icsunonove]

Lee, if yours is standard, simply fit a Fensport pulley and make sure the standard intercooler is working to its maximum efficiency. You'll be surprised how good the results are! (I was )

[AlexE]

It would be difficult to fit though Alex, wouldn't it?....

actually not that difficult...does require a different intake manifold though.....you can see further details of the NA 4ag we put an Mercedes/Eaton SC on here:


http://media-icon.co.uk/


(the car is no longer owned by my friend but the details on this website are a re jig of his original build notes, oh and please note its a Lotus 7 type kit car not a AW11 but I'm sure a similar setup would fit in a MK1)

[Lauren]

I did look at the fensport pulley 12-14psi apparently. May do that as a future mod money willing. I wanted to sort the cooling out first(intercooler, spal fan, possibly an oil cooler, some hideous air intake

Have you ever used exhaust rap, the label say 50% heat reduction in engine bay and can you use is on a stock manifold, and while im thinking of it TRD thermostats open at 70 degs is this good?

GASP......

Finished

Don't bother with a fan under the intercooler, tis a waste of time. Either duct air from outside and seal teh intercooler off from teh engine bay entirely or go for a water/air intercooler (see my webshite under Bearding/intercooler ducting). I did lots of temp tests with thermocouples before and after the intercooler and improved the efficiency by 100%.

Do you do trackdays? If not i'd say i wouldn't overly worry about increasing the cooling capacity as its not such an issue on teh road really.

Also don't do the crappy ABV mod as described on various sites like mr2sc.com. The best and only way is to remove the ABV entirely from the equation.

In fact i'm just enquiring into getting a load of SC outlet pipes that do away with the ABV made up for the SC list like i had on my car a couple of years ago:
http://homepage.ntlworld.com/mark.nias/ ... ultet1.jpg

Other details of my ducting here:
http://homepage.ntlworld.com/mark.nias/beardpt2.htm

If you want an oil cooler get one off an NA, you will need the sump, oil filter bracket adn pipework too. Find someone who is scrapping an NA and grab all teh stuff, reckon you could get it pretty cheaply tbh. Its a good design as its a water oil cooler and is well out of harms way plus is fairly indestructible.

[j0nathan]

It would be difficult to fit though Alex, wouldn't it?....

actually not that difficult...does require a different intake manifold though.....you can see further details of the NA 4ag we put an Mercedes/Eaton SC on here:


http://media-icon.co.uk/


(the car is no longer owned by my friend but the details on this website are a re jig of his original build notes, oh and please note its a Lotus 7 type kit car not a AW11 but I'm sure a similar setup would fit in a MK1)

Are you saying that you superchacharged a NA 4-AGE rather than a 4-AGZE? I would be interested in more details. What modifications were carried out to the engine etc to enable to take the boost in standard form. I have heard that you can not push more than approx 5psi before a standard NA lets go. Enquiring mids want to know...

Jon

[AlexE]

Are you saying that you superchacharged a NA 4-AGE rather than a 4-AGZE?

Jon

Jon, yes thats it....an eaton SC from a mercedes was strapped to an NA 4AG not a supercharged 4AGZ. I have to say that I did not personaly do this it was a close friend of mine who must take all the credit. The engine was from a 1987 MK1 MR2 and was completely standard...the engine was completely untouched other than for service items and the replacement of the standard ECU with a Megasquirt engine management system...all built from parts and tuned from scratch. The supercharger from the mercedes came with an electromagnetic clutch on it much like the 4agz and this was run along with the standard 4ag crank pulley which ended up producing aproximately 6psi of boost, all tuning was done on the road and unfortunately the car was sold on before any rolling road figures could be measured, I can confirm however that the car was far from slow!

[Icsunonove]

Alex, you've got me really interested now!

And a 4-AGE engine with 6 psi boost would be quick in a roller skate / Caterfield clone.....

Is 6 psi the recommended maximum boost using standard 4-AGE pistons and Megasquirt? Or was it simply a case of that's what it produced with the standard 4-AGE pulley?

Can Megasquirt take inputs from the 4-AGZE knock sensor? and knock back the ignition timing?

[AlexE]

Alex, you've got me really interested now!

And a 4-AGE engine with 6 psi boost would be quick in a roller skate / Caterfield clone.....

Is 6 psi the recommended maximum boost using standard 4-AGE pistons and Megasquirt? Or was it simply a case of that's what it produced with the standard 4-AGE pulley?

Can Megasquirt take inputs from the 4-AGZE knock sensor? and knock back the ignition timing?

the 6 psi we ended up with was to be honest a bit of a hit and miss affair...the supercharger used was suposed to be an eaton M45 (from the mini) which we calculated would give aproximately 3psi of boost...which was about what my friend was looking for (just a little extra...remember the car weighs 500kg) as it turned out we discovered during the build up that the sc was a M62. My friend decided he wanted to keep the clutched operation of the supercharger and it just so happened (lukily seeing as we were aiming for 3) that the larger sc produced 6psi. I would not like to say if this is the limit for the NA 4ag a lot of how much boost you can safely run comes down to the tuning......

As for the megasquit and the 4agz knock sensor...this is not something I have looked into as yet...you are probably best off asking the question over on the megasquirt messageboard.

[LeeHoochie]

If you want an oil cooler get one off an NA, you will need the sump, oil filter bracket adn pipework too. Find someone who is scrapping an NA and grab all the stuff, reckon you could get it pretty cheaply tbh. Its a good design as its a water oil cooler and is well out of harms way plus is fairly indestructible.

Ive actually got an old mk1 n/a sitting on my drive way(being used to give a s/c a better life )

I thought the s/c had the same oil cooler (I haven't actually looked to be fair)

Also, as im new to the would of s/c's "whats an ABV )

[Lauren]

If you want an oil cooler get one off an NA, you will need the sump, oil filter bracket adn pipework too. Find someone who is scrapping an NA and grab all the stuff, reckon you could get it pretty cheaply tbh. Its a good design as its a water oil cooler and is well out of harms way plus is fairly indestructible.

Ive actually got an old mk1 n/a sitting on my drive way(being used to give a s/c a better life )

I thought the s/c had the same oil cooler (I haven't actually looked to be fair)

Also, as im new to the would of s/c's "whats an ABV )

The SC does not have an oil cooler. JDM spec is not as good as UK spec in this respect. Ditto rear ARBs as some SCs had them, but some did not. All UK cars did.

ABV is basically a valve that bleeds off excess boost over 8psi back to the inlet on the non-pressurised part of it. This needs to be removed if you fit a big pulley as otherwise all teh extra boost goes to waste. Please ignore the crap way of sorting this problem which reverses the vacuum on the VSV.

The only solution is to remove the ABV entirely as that way you can ensure all boost generated by the SC goes to the engine.

[MartG]

Lauren - if you remove the ABV how does the engine breathe when the SC isn't running ? Apart from its function of controlling max boost under ECU control ( which is disabled by the mod detailed here http://www.mr2sc.com/websites/tech/abvlines.htm ), it opens to bypass the SC when it isn't engaged allowing air to pass straight between the throttle and the inlet manifold.

[LeeHoochie]

I'll start working on removing the said items at the weekend

I reserve judgement on the ABV mod once you've discussed it a bit

Cheers for the advice so far