My 93 BMW 325iS coupe (56K beware)

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davebmw
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My 93 BMW 325iS coupe (56K beware)

Post by davebmw »

I thought i would get some pix up on this site of my car as it was and as and when I do any mods.
I bought my coupe pretty much standard with FSH in october 2003, I have always wanted and M3 but have never been able to afford to keep one as a day to day driver.
I got this one with 35000 miles 2 owners and perfect condition.
It has all the Motorsport trimmings and a sport bodykit which i think is an alpina or hartge but have never been able to find out for sure.
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I realised after owning it for about 6 months that it needed something to stiffen it all up a bit and get the brakes sorted.
i fitted EBC greenstuff pads to cross drilled and grooved discs all round.
Changed all the rubber bushes for polyurethane all round,
Lowered the suspension by 40mm with eibach springs.
Fitted bilstein sprint shockers all round.
replaced the tyres with Vredistien Ultrac 225, 45, 17.

Soon I found I was driving like a bloody maniac because the car sticks like nothing i have known, i could defy physics in corners, it was fantastic.
trouble is now the chassis is so capable that i need more power so is 2006 i started planning to fit a super charger, knowing that the engine really was an unknown quantity at this point i decided to do a total rebuild with forged pistons, polish and port the head and replace every bearing seal gasket and any wearing part.
I had suspect noise from the Vanos unit, so i dismantled it and found the reason was because i had the pre plate spring version which I updated to the 95 onwards model:
If you ever wondered how VANOS works its all down to this piston actuator that slides the splined cup in and out of the end of the intake camshaft, it can advance the cam by upto 12 degrees:
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the piston fits in the cylinder and is push pulled by oil pressure, controlled by a solenoid valve:
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the head was skimmed, pressure tested and flow checked, the combustion chambers polished equalized and valves ground in.
the block was ground and bored out to the maximum 84.5mm.
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The crank was checked and polished.
The whole thing had to be perfectly timed so i made up some tools.
There is a cam locking jig, I machined it from a scrap piece of Ally 12mm thick.
A flywheel locking pin I turned down from the shank of an old 16mm masonry drill.
A VANOS spanner to turn the exhaust to intake chain which allows the fitting of the splined cup into the end of the cam.
and a secondary chain tensioner pin, I didn't make that one it came with the new tensioner.
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the whole engine was re assembled from new bits in 24 hours by little old me!
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The engine went back in the next day it took me 8 hours to slot it back in and i took it for a test drive at 8pm and used the motor bike method of running in which basically means make the bugger work get it singing at the sweet spot and push it up hills etc.
After 2000 miles of mixed driving it was clear that I had regained all the power I had lost over the years and some more at this point I thought OK I had to do something about the air getting in so I bought a K&N CAI off Ebay:
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This really makes a serious difference on its own but obviously what goes in must come out, so again, Ebay nice Scorpion STW twin 3 inch tail pipes:
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And I took a fancy to these alloys with the widest tyres you can fit without serious body mods:
Front 225 x 40 x 18, Rear 255 x 35 x 18.
I had the rim lips machined with small grooves to prevent the tyres rolling off, I thought about this long and hard after I discovered my 17 inch wheel tyre combo was getting sidewall wear from hard cornering.
Now the wear patch stays on the tread!
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I chose Vredistien tyres again as they are super grippy and last 25K miles! this set are called Sessanta and have a really cool continuous tread design, so you get very little tyre noise.
I can now corner so fast it hurts my neck, and believe me I have a thick neck!


I will keep adding to this thread as i have to take more pix of the supercharger project and MS2 work i have done recently.

over and out for now, i'll be back soooooooon!
Last edited by davebmw on Sun Aug 10, 2008 6:22 pm, edited 2 times in total.
93'BMW 325is M50B25TU, Rebuilt 06/06, JE10.5:1, polish&port. Scorpion BB, K&N CAI, TEJ21 WBO2, '07 M3 Evo 18" 225F, 255R, EBC Kevlar, Bilstien Sprint, Polyflex. Head rebuild Oct'08, OEM+FSE FPR, MS2v3.0_DJB Custom, Extra 2.0.1
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Fred
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Re: My 93 BMW 325iS coupe

Post by Fred »

Cool car Dave! I always liked the E36 shape :-) I had planned to get one when I came here, but for a variety of reasons I haven't. One of those reasons is compulsory insurance which I can't get with a driving record like mine ;-)

Are those flat top pistons? What is the compression ratio? I like seeing fresh builds like that :-) Especially when they are done properly in detail.

Fred.
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davebmw
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Re: My 93 BMW 325iS coupe

Post by davebmw »

They are 10.5:1 i had originally only planned for 10 psi of boost, when I ordered them from JE Pistons they ballsed up and sent 8.2:1 by mistake first but told me to keep them so if I want to go over the 10psi i can at a later date, I'll take a shot or 2 of them tomorrow, they are really pretty!
93'BMW 325is M50B25TU, Rebuilt 06/06, JE10.5:1, polish&port. Scorpion BB, K&N CAI, TEJ21 WBO2, '07 M3 Evo 18" 225F, 255R, EBC Kevlar, Bilstien Sprint, Polyflex. Head rebuild Oct'08, OEM+FSE FPR, MS2v3.0_DJB Custom, Extra 2.0.1
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Fred
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Re: My 93 BMW 325iS coupe

Post by Fred »

davebmw wrote:They are 10.5:1 i had originally only planned for 10 psi of boost
If it's a street car, are you planning water injection? If it's not a street car, what are your plans for high octane fuel? You'll need a bloody tight tune with 10.5 and 10psi on 98ron :-)
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
davebmw
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Posts: 331
Joined: Sun Jul 13, 2008 2:58 pm
Location: South Wales, UK

Re: My 93 BMW 325iS coupe

Post by davebmw »

The plan was to use a large intercooler and water injection, but now that i have the dished pistons i will probably go for a second rebuild and more boost with a twinscrew or roots (Merc Eaton) with intercooling.
I'll have to play it by ear a little, the guys in the US are running 10 psi with this CR with just intercooling. but i like the safe options.


Last bumped by davebmw on Sun Aug 10, 2008 2:59 pm.
93'BMW 325is M50B25TU, Rebuilt 06/06, JE10.5:1, polish&port. Scorpion BB, K&N CAI, TEJ21 WBO2, '07 M3 Evo 18" 225F, 255R, EBC Kevlar, Bilstien Sprint, Polyflex. Head rebuild Oct'08, OEM+FSE FPR, MS2v3.0_DJB Custom, Extra 2.0.1
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