BMW E30 SR20DET Conversion

[Guest numbersixteen16]

Even though alot of BMW enthusuasts will dissagree with my engine choice, I believe it would be great scince the BMW engines have not proven to be the most reliable engines and getting power out of them is quite expensive. I chose the SR20DET because of its good standard power figures, quite good reliability and i want to eventually start rally and superlap.

Hopefully the car will eventually become completley set up for racing, including roll cage, widened body, race spoiler, the complete works (however still road legal).

Need to start somewhere so I chose the engine, as a 316 is pretty gutless and im sick of having engine failures.

I am looking for someone who previously did the conversion to list the things needed, as well as an opinion of the best gearbox to use, Im wanting a six speed that is reliable (Ive heard that the silvia six speed sucks, not sure why though) and not too expensive, I thought the 350z gearbox sounded good if I could adapt it to the sr20det.

Also what build time am I looking at? And what cost if I did it all myself? I have all the engine hoists and may soon be moving into a factory as well.

[Wervie67 0]

Incary is doing this conversion at the moment, give him a PM

[Jay 735i 0]

Im wanting a six speed that is reliable (Ive heard that the silvia six speed sucks, not sure why though) and not too expensive, I thought the 350z gearbox sounded good if I could adapt it to the sr20det.

The Silvia 6-speed doesn't suck, it's just not as strong as the 5-speed and by the sounds of your plans, you'll be wanting the strength. Plus if you go for it with the SR20, there are options for making the 5-speed even stronger (OS Giken gearsets etc). However the 350Z box is reputed to be very strong from factory (you'd almost think that Nissan knew the 350Z would be used for drifting by a lot of customers and over-engineered it as a result! ). Not heard of an adaption to the SR20 though, as most are happy with the 5-speed box.

Timelines are down to your work ethic, but draw up a project plan, list all the jobs that need doing, put a realistic time against each and add them up. Then triple that time. And if you're me, add 2 years.

[Venatus 2]

Im interested to hear about doing the engine and gearbox mounts at some point...

[CamB 48]

My 2c worth - its pretty debateable whether a 6spd is worthwhile on a car with an appropriately sized turbo and wide enough power band.

[Gaz 1042]

The Silvia 6-speed doesn't suck, it's just not as strong as the 5-speed and by the sounds of your plans, you'll be wanting the strength. Plus if you go for it with the SR20, there are options for making the 5-speed even stronger (OS Giken gearsets etc).

This.

Forget the 6 speed and go for the 5speed. The 6 speed is weaker because it is the same size as the 5 speed box meaning everything has to be smaller to fit in the extra gear making things weaker.

[JiB 0]

None of my friends with hard working sr20dets are more reliable than my m20s. You definitely want rocker arm stoppers as they don't like high revs all that much.

If pfl, I don't think widebody is necessary. 17x8.5's should be able to fit under rolled guards. If you want big rubber 17s is the way to go on an e30 - lots more space than 15/16 because of the way the struts slant.

Another issue is the classes that you'd be restricted to in racing. You'll be stuck with the big boys in almost everything. But I guess ss2000 might be a goer.

The brake booster on e30s will be right next to your Turbo manifold (and probably stopping you from mounting the sr as far back as convieniently possible). Maybe factor in the cost of a pedal box - then you're completely free to pick your brake bias and calipers. The SR box is also quite long iirc, so the pedal box will let you sit further back in the car for the awesome faux supertourer feel.

Decent cage, seat, harness, paint, suspension, brakes, rims, tyres will be pushing 10+k choosing semi-decent components. This excludes the drivetrain.

Good luck with the project. A sorted e30 with a boosted 4 has always been a pipe dream for me!

My 2c worth - its pretty debateable whether a 6spd is worthwhile on a car with an appropriately sized turbo and wide enough power band.

+1

But if you're set on a strong six speed - OS Giken and PPG have suitable bits. (Your wallet won't like them though)

[|ncary 0]

I have receipts totaling 5k for engine, gearbox, turbo 'pish' thing and air cooling bits, and custom engine/box mounts. Probably add another 1 for wiring and driveshaft and other bits.

Will definitely need to move the brake booster if wanting to mount the engine back a bit. And will need a shifter linkage like what a 300ZX has apparently. Unless you do as JiB says

[pureboiracer 0]

i will join you one day.... all in good time... can just imagen opp lock all the way through the infeild of manfield now... ahhhhhh..

[crshbndct 0]

i have just made the mistake of purchasing a rebuilt fj20 so i will be following the nissan engine into e30 quite closely.

it was too good of a deal to pass up.

(my m30 plans are now shelved)

[CamB 48]

Awesome! FJ20s are mint. Kind of like the BMW E30 M3 engine (S14), IMHO.

[crshbndct 0]

yeah its all rebuilt to factory spec but has a buggered turbo. might even be easier to fit than an sr20 because its out of an s12 silvia, so has the shorter intake manifold, and it uses l-jetronic ecu which is the same as my pre facelift bmw.

[No name user 379]

FJ20 is by far a better motor than a sr20

[Forrest 35]

You should use this shell mate, http://www.bimmersport.co.nz/forums/index....showtopic=30860

Has a pedal box set up already, sorting your brake booster clearance issues, also stripped out etc ready for a cage

[Guest numbersixteen16]

i have just made the mistake of purchasing a rebuilt fj20 so i will be following the nissan engine into e30 quite closely.

it was too good of a deal to pass up.

(my m30 plans are now shelved)

Would be happy to purchase the fj20 off you if you live near Auckland, just considering the idea of an fj20. But what is a good price for one, can get a complete sr20det front cut for $3000, or engine + gearbox for $2200. Can I get a fj20 for $1000 less? What did you pay for yours?