IE Stroker Kit

[SStuart]

Hi Guys

Im thinking of ordering an IE 3.1l M20 stroker kit.

Has anyone had experience with this product, and is there any

advice to share in this regard?

Also, if you have a knowledge of stroking m20b25, is there any IE essential additional items you would recommend?

The below URL is a direct link to the product
http://www.iemotorsport.com/bmw/E30-engine/m20-32.html

Your comments will be greatly appreciated.

NB: I am not interested in an engine swap, before it is suggested.

Cheers guys

[daimlerman]

The IE 'kit' is regarded as a very expensive way to gain capacity.

Little more than a crank from a 2.8 M52 is needed to take an M20 to 2.8 ltr,which ca be bought for a few quid.

Back in the dark ages,when daimlerman was a lot younger,the way to stroke an M20 was to use the crank from an E28 525e,to form a 2.7.This was the route that I went.I started with a 2 ltr engine,so already had the correct head,added a 325i inlet and gained almost 45bhp....

[SStuart]

The IE 'kit' is regarded as a very expensive way to gain capacity.

Little more than a crank from a 2.8 M52 is needed to take an M20 to 2.8 ltr,which ca be bought for a few quid.

Back in the dark ages,when daimlerman was a lot younger,the way to stroke an M20 was to use the crank from an E28 525e,to form a 2.7.This was the route that I went.I started with a 2 ltr engine,so already had the correct head,added a 325i inlet and gained almost 45bhp....

Hi Daimler

Thanks for the response.

The kit certainly is expensive. However, i am looking for more than 2.7/2.8 i would like to go 3.1/3.2 if possible.

Do you have an idea if anyone in UK sub assembles stoker kits in the same way as IE?

[daimlerman]

You need to be talking to zoner's like reggid or HairyScreech,they have the knowledge of just what bits you would need to stroke out to that sort of capacity.

BMW have used the same bore centres for years,which does help with this sort of thing.

So you need to research which crank from which engine you need...and to discover how far you can over-bore the block...

On a more practical note,similar torque/BHP can be obtained far more cheaply with a conversion,the M50 engine range is an almost 'bolt in' conversion,V8(M60/62)is more complex,but can be done.

Tuning M20 is an expensive hobby,work on the basis of £10 per 1 bhp gain.

[SStuart]

You need to be talking to zoner's like reggid or HairyScreech,they have the knowledge of just what bits you would need to stroke out to that sort of capacity.

BMW have used the same bore centres for years,which does help with this sort of thing.

So you need to research which crank from which engine you need...and to discover how far you can over-bore the block...

On a more practical note,similar torque/BHP can be obtained far more cheaply with a conversion,the M50 engine range is an almost 'bolt in' conversion,V8(M60/62)is more complex,but can be done.

Tuning M20 is an expensive hobby,work on the basis of £10 per 1 bhp gain.

Thanks for the feedback.

Ill try get in touch with the guys.

m20 is my preference, i know its not economical to tune an m20, but what the heck!

[HairyScreech]

Wondered why my ears were burning.

IE kit is very expensive over here, add on the import duty and it's a very hard sell.

M54b30 crank, keep the rods there very similar to S50 or M52b28 ones, add some JE pistons (I think they do ones with the right crown shape) and if you really want then spec some for an 85mm or 86mm bore for your 3.1/3.2
Edit - JE make these, its easy for them to tweak the bowl for more or less compression, to work with a stroker they need a higher pin height and smaller top land. But regardless this is the crown shape you want for a stock 325 combustion chamber, concentric bown pistons for this kind of application are shite and really bodgey with a stock 325 chamber head.
http://www.r3vlimited.com/board/showthread.php?t=125813

Thing is the m20 head does not breath well enough stock for much over 2.8 to give good gains.
A reasonably normal 2.8 with a good head is just as good.

Then again a 3.1 bottom end with a worked head with enlarged inlet valves (forget the exhausts they are big enough already) will really get things moving.

With the kind of capacity your talking the standard manifold will really be choking things, plan for a custom inlet that uses a large throttle body to add to the above if you really want things to work together.

[SStuart]

Wondered why my ears were burning.

IE kit is very expensive over here, add on the import duty and it's a very hard sell.

M54b30 crank, keep the rods there very similar to S50 or M52b28 ones, add some JE pistons (I think they do ones with the right crown shape) and if you really want then spec some for an 85mm or 86mm bore for your 3.1/3.2
Edit - JE make these, its easy for them to tweak the bowl for more or less compression, to work with a stroker they need a higher pin height and smaller top land. But regardless this is the crown shape you want for a stock 325 combustion chamber, concentric bown pistons for this kind of application are shite and really bodgey with a stock 325 chamber head.
http://www.r3vlimited.com/board/showthread.php?t=125813

Thing is the m20 head does not breath well enough stock for much over 2.8 to give good gains.
A reasonably normal 2.8 with a good head is just as good.

Then again a 3.1 bottom end with a worked head with enlarged inlet valves (forget the exhausts they are big enough already) will really get things moving.

With the kind of capacity your talking the standard manifold will really be choking things, plan for a custom inlet that uses a large throttle body to add to the above if you really want things to work together.

the information above is just why it is so important to be a member of the zone!

Thanks for taking the time to get back to me on this. I will digest and then come back with the questions.

By any chance, do you know anyone mainland that sub-assembles kits?

[reggid]

there is nothing the IE kit has that cant be sourced elsewhere.

custom pistons you want the JE with OEM dish-dome shape to retain good squish characteristics and chamber centreded around the plug on the hotside of the chamber. they can do both 8.8:1 style or 9.7:1 style best bet is through "topend/racetep". just need the short compression height to match the stroke/rod length and either 85 or 86mm bore...

IE can do the 8.8:1 dish dome in a ross racing piston (it is a relatively new addition) but just get pistons/pins and rings and not the whole kit if you go through IE the shipping will be alot. speak to andrew at IE if you want to go through them i can provide his email

you want something around 10.5 to 11:1 compression with a street friendly camshaft which is easy to achieve with this style of piston. i can give more details on the static CR and cam combinations to achieve a dynamic compression ratio of about 8:1 which is a good target pump fuel

as eluded to above a 3.1L kit wont really add proportionally more peak hp (dimisnshing returns) but mid range and bottom end will leave the others for dead if you cam it correctly with good compression and so forth which is ideal for a street driven vehicle

[SStuart]

there is nothing the IE kit has that cant be sourced elsewhere.

custom pistons you want the JE with OEM dish-dome shape to retain good squish characteristics and chamber centreded around the plug on the hotside of the chamber. they can do both 8.8:1 style or 9.7:1 style best bet is through "topend/racetep". just need the short compression height to match the stroke/rod length and either 85 or 86mm bore...

IE can do the 8.8:1 dish dome in a ross racing piston (it is a relatively new addition) but just get pistons/pins and rings and not the whole kit if you go through IE the shipping will be alot. speak to andrew at IE if you want to go through them i can provide his email

you want something around 10.5 to 11:1 compression with a street friendly camshaft which is easy to achieve with this style of piston. i can give more details on the static CR and cam combinations to achieve a dynamic compression ratio of about 8:1 which is a good target pump fuel

as eluded to above a 3.1L kit wont really add proportionally more peak hp (dimisnshing returns) but mid range and bottom end will leave the others for dead if you cam it correctly with good compression and so forth which is ideal for a street driven vehicle

thanks for the info.

this thread is getting more informative with every post.

I suppose that with assistance of experts such as yourself, i could spec and put together a kit mainland.

It will be my first attempt at a stroker and thats why i sound lost.