5spd swap question

[Conrad311]

Hey i have a question,

I have an '87 325is auto and i want to put in a getrag 260, but my questions are this:

My tach shows the redline to be 4750 :( But the tach on the possible donor car, an 88 325i, has a different tach and a higher redline. is there a different redline due to changes in the motor with the later models or is it that the auto slushbox is just a piece of shit?

to what rpm can i safely turn my motor with the 5spd?
also do i need to swap the clusters?
thanks for the help

[jlevie]

A 325 i/is should have an M20B25 engine, which has a 6500 rpm redline. ETA cars (325 e/es) have an M20B27 engine which has the lower redline. Therefore the possibilities are:

You have a 325e/es, not a 325is
You have a 325is and someone swapped the engine and cluster for those from a 325e/es
You have a 325is and the wrong cluster is in the car and the redline is actually 6500rpm

Plugging the last 7 of you VIN into realoem.com will tell what car you have.

[Conrad311]

I know its a 325is, its the m20b25, i know its an is its got all the options, lsd, recaros, all power, and i put it in realoem and it says 01/87 e30 325i coupe m20 automatic
so i assume they just didnt have the option for is, because aside from the diff, it was all cosmetic.
so im going to pull the cluster and get the part number from it and see if it is for an eta motor.. i wonder why that cluster is in there, i know both of the POs and i know they werent the type to go replacing parts..

[Farbin Kaiber]

So RealOem says it's an i, and not an iS?

[CorvallisBMW]

Sounds like one of the POs replaced your 'i' cluster with an 'e' cluster.

[DJB]

You should verify that the engine is indeed the original M20B25. A M20B27 (325e) engine requires a transmission with sensor holes in the transmission. A transmission from an early 325i will have the bosses on the casting, but the holes will not be machined.

If you do have a M20B25, it's likely that the instrument cluster was swapped because of a broken odometer gear and the service guy didn't know the tach needed to be moved over.

The engine computer limits the redline under power, but it's still possible to over-rev by down-shifting. The original rocker arms castings start breaking at 7100-7200 RPM, while the new castings are good for 7400 RPM or slightly higher, but the engine makes no power up there.

[Conrad311]

Yes it is deffinatly a 2.5 i just did a head swap and im pretty familiar with e30s, ive had 2, about to get another, and my girl has an 89 ix, its with out a doubt a 325is, im just not sure where the cluster came from or why, but it doesnt work right, the speedo freaks out at about 80mph and the temp guage doesnt work, the SI lights dont really work. they flash sometimes, either just the yellow or the yellow and 2 reds. i dont know if that could be the si batteries or if its just shot

[blunttech]

Yes it is deffinatly a 2.5 i just did a head swap and im pretty familiar with e30s, ive had 2, about to get another, and my girl has an 89 ix, its with out a doubt a 325is, im just not sure where the cluster came from or why, but it doesnt work right, the speedo freaks out at about 80mph and the temp guage doesnt work, the SI lights dont really work. they flash sometimes, either just the yellow or the yellow and 2 reds. i dont know if that could be the si batteries or if its just shot

reading your first posts blows your "im pretty familiar with e30's" theory out of the water

[REVHARD05]

reading your first posts blows your "im pretty familiar with e30's" theory out of the water

what does your post have to "add" to this thread?