Jump to content
SAU Community

BMW engine conversion


finch
 Share

Recommended Posts

Hey guys,

Alright here I go. I own a 1983 e30. The engine is on its way out, the cylinders were down on pressure and a couple of other little things. the car is currently off the road. I believe the car to be straight. There is no rust, the owner before me was an enthusiast so the car is in excellent condition.

Instead of getting a new car I thought I would try and fix the one I have. And make a machine out of it at the same time. It was suggested that I put a SR20 in it. I have been looking at getting a sr20 front cut. But i thought if i could why not try a RB20 or even better a RB25....

I have done a bit of research and have found (i hope) that its not that hard to do, (with the sr20 det anyway) gearbox lines up with the hole and everything, Nissan nose needs to be welded onto tail shaft, the main problem is that the exhaust is on the wrong side, which you cant do anything about. Now obviosly there would be more involved with the 6cyl conversion

Just wondering if anyone has done or seen done a similar engine swap, and any other problems ect. or a contact to someone who has, (brisbne area)

All suggestions/ help is greatly appreciated

Thanks

*i know nobody likes/ takes seriously, newbies.... but i am fully serious about this and genuinly need some advice/help

thanks again

Link to comment
Share on other sites

  • Replies 58
  • Created
  • Last Reply

Top Posters In This Topic

cool, thanks heaps for that.

i have been told that the engine mounts are not that hard to fabricate.

but i wouldnt know for sure.

hmmmm didnt think about the rotor.... but i think i rather not do a rotory

though (nothing against them)

would there be any major benifits getting the rb25 over the sr20? when it

comes to mods etc

Link to comment
Share on other sites

and can make just as much power as an RB25.

easily?

yeah i was leaning toward the sr.

and plus i know a mechanic who has done a sr converion in an e30.

thanks for all the response... and that link!

Link to comment
Share on other sites

i just though that if i could get some power i would see what would be involved in puttting an rb25 in there instead

what about the rb20, would that have any advantages over the sr? less tourqe?

Link to comment
Share on other sites

wow thats some pretty serious power from a 4cyl.

could you explain the whole cv joints being a problem please. (im kinda new to cars)

i understand what a cv joint is, i think. is what your saying that they would need to be upgraded?

Link to comment
Share on other sites

I personally don't like the idea of a 4cyl in the BMW, I am used to and prefer the sound of a nice tuned sounding 6cyl coming from them.... one of my mates has a 3-series with a 1JZGTE in it putting out 218kw @ wheels and that goes plenty well ;)

Link to comment
Share on other sites

a mate of mine had an E30 323i JPS, with the 2.3L it would break CV joints sometimes when dropping the clutch at high RPM.

Then he put the 2.5 out of a 325is and he broke his CVs almost every week.

Also there was a black E30 with an SR20 in it ,on one of the Serious Performance vidoes and he had the same problem he actually broke one while taking off on the video.

So i would say while your modding everything upgrade your rear CV joints as well because its a pain in the ass grettin the car towed everytime you break a CV.

"DO IT ONCE AND DO IT RIGHT" best adivce ive ever been given

good luck with the conversion

my uncle and i might be doing the same to his old BMW 2002 ;)

Link to comment
Share on other sites

I personally don't like the idea of a 4cyl in the BMW, I am used to and prefer the sound of a nice tuned sounding 6cyl coming from them.... one of my mates has a 3-series with a 1JZGTE in it putting out 218kw @ wheels and that goes plenty well :)

what about the E30 M3? they were 4 bangers ;)

oh yea and so were the 2002 tti 4cyl, single cam, turbo.

Link to comment
Share on other sites

i see, thanks 2guup2, and yes when i do do the conversion i intend to do it properly! no shortcuts.

he he.. the old 2002, that would be a cool car to do a transplant in

bmw 4cyl arent that great with the exception of a few:

the s14 m3 (1986 to 1991) engine have roughly 200 bhp from factory (2 - 2.3L (i think) 4cyl) , there was another version(1990), with up to 240. they are an awesome 4cyl n/a engine i would put one of those in if i thought i could get one cheap and i knew i could get parts that were redilly avaliable... but yes the 6s are a lot better

lithium: do you know any major/ minor problems you friend had with his conversion?

Link to comment
Share on other sites

I had an E30 323i with a 2.9L conversion. Blew two diffs, one gearbox, no CVs. Go figure.

Torque monster.

Build a 2.9 with an GT28 hanging off the side...

Block and head from E30 325i, E30 323i rods, custom overbore pistons (sorry can't remember the exact size), crank from E36 328i.

I love 2002tii... my old man and I restored one about 10 years ago :(

Here piccy :(

Link to comment
Share on other sites

my mate has the 2.5L in an E30 -- soon to go turbo, motor has just been rebuilt due to huge Cam wear! goes alright with just the 2.5L bottom end - 2.3L head and Lotus forged pistons! wierd combo but when the turbo goes on should be quick! only thing with these cars is lack of room down the car for exhausts.. 3inch would scrape out big time!

only thing to watch that i know of with these things is the rubber mount from gear box to tail shaft!

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share




  • Similar Content

  • Latest Posts

    • And yes would be going to tomei Japan for sure as it’s closer to me … 
    • Yeah I heard the same. Might be hard to order one. But then I guess can go to hks or go to a more expensive n1 block with tomei. Guess will jump the hurdle once I get there next upgrade around. I can’t get work done in the states as the lead time will take for ever on top of shipping to Hong Kong. 
    • https://www.platinumracingproducts.com/en-us/products/nissan-rb26-cast-blocks This is the solution I was thinking of. I would stay away from Tomei USA, their quality is a question mark to me. If you want an engine machined in the US contact Club DSPORT: https://clubdsport.com/ Tomei JP is probably fine but I recall they stopped doing pre-assembled short or long blocks. In general it's pretty tough to get any kind of RB26 block at the moment with Nissan so severely backordered.
    • PAR specifically offers stock ratios in their gearset and you could do whatever ratios are physically possible supposedly for no extra cost. I agree 6 ratios is better than 5, the factory 2nd gear is equivalent to the Getrag 2nd gear if you account for the differing final drive ratio though. The Getrag 3rd gear with a 3.916 final drive is equivalent to a 1.6 2nd gear in the FS5R30A. I'm about to swap the transmission out on my car, I'm tempted to send the one I have now out for rebuild with the standard "cross ratio" gearsets out there to see if it really makes such a big difference the next time I pull the transmission.
    • This is what I was looking at next:  https://www.z1motorsports.com/engines/tomei/tomei-rb26-28l-short-block-assemblies-p-45479.html as we can’t bore the cylinders out in hk so better just buy the whole lot in one and install then retune. Everyone saying the weak link are the bolts holding the rods together. I already did valve springs, arp head bolts, hks racing coils, nismo fuel pumps and pressure regulators, injectors etc for the top of the engine. 
×
×
  • Create New...