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Discussion Starter #1
After much R&D and a few hurdles the 4.2 stroker build is up and running .

She just has to be mapped and a few little extras and she's good to go .

It's been along time coming , but on the few short drives that I've had so far she feels like a highly spirited E34 M5 .

More details to follow , basic spec ;

95mm bore

98mm stroke

12:1 CR Pistons

H beam rods (147.5mm iirc )

Raceware Head Stud Kit

Mls head gasket

Bespoke Exhaust Manifolds

Bespoke Stainless Decat exhaust with x pipe

4.5kg Chromoly Billet Flywheel

Uprated Sachs Clutch

Larger alloy rad .

6 speed brakes .
 

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Great to hear some news on this project David

Have you calculated the dynamic compression ratio and what fuel will you be using ?

Depending on cam timing the DCR will be high with 12:1 CR and a longer stroke

Any ping problems ?

This should be conservatively a 390 to 400hp motor by my calcs with more available with software changes, 315 to 320 RWHP

It Will be good to get some knowledgable comments on this stroker conversion from someone dong it and not theory

Mid range torque should be awesome
.
 

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Discussion Starter #4
Hi guys .

Yes , this is the Aussie PPF Kit after a number of discoveries and alterations to get it up and running .

In the uk there are only a few petrol stations that sell >97 ron fuel .

Ideally we want to run on the highest octane available and at present it's got 99 ron fuel in the tank .

My man is currently looking at the fuelling and will be mapping her after a run on the rollers.

For now , I am simply overjoyed to have her up and running and getting her through a uk ministry of transport test , including emissions test .

See video of initial running ;
E34 M5 S38B42 Stroker:

http://youtu.be/xNfBPVQOpPg
 

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Why not... new crank and rod+pistons... and the block rebored
David said "After much R&D and a few hurdles the 4.2 stroker build is up and running ."

"Much R+D and a few hurdles" doesn't sound like it was an easy bolt in

What I want to know is this crank , rod and piston related or other engine components
 

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David , the engine is going to ping like hell on pump gas with stock cams

DCR > 9:1

You're going to have to tune quite rich at high rpm or run water or water / methanol injection

Aquamist UK does some very nice systems
 

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Discussion Starter #19
Apologies for delay in replying guys and gals , I unwisely edited my contact details and had to wait for admin approval before being able to post .

Meanwhile ,

Yes , this was one of the first run of 5 cranks produced and , as far as I know , one of the first to be up and running in an E34 M5 .

We were part of the guinea pig development of the kit and encountered issues such as pistons sitting 1.65mm above the deck when the spec was flush , rods that fouled the underside of the piston etc

All of these teething issues resulted in delays , but Thomas was quick to address issues and provide solutions and the resulting kit will now be plug and play .

We chose to fit Cat Cams of 291° hence the lumpy idle Bumbaclut picked up on .

That said , once the fuelling / mapping is optimised via the factory motronic I expect the engine to be a true powerhouse whilst retaining drivability .

I have driven the car for a number of miles on the standard map without a lambda or a maf and it still felt crisp , so, once it's mapped using a wide band lambda situated in the x piped stainless decatted system , I anticipate positive results .

A few pics ;
 

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