730 cylinder head

[thepitscars]

Hi all - my friend has an E32 730 - I am 99.9% sure it has a blown head gasket - I am also pretty sure that the head will have rotted out coolant passages (he ran plain water for many years) - my question is will a cylinder head from a 735 fit ? - or ones from earlier (or later) models ? Cheers. Also will I need to get new head bolts ?

[shogun]

use realoem with the car's VIN and find out the correct part number, then go back to realoem first page and paste the part number into search by part number and all BMW models will be shown which use the same part number.
Head bolts I would in any case use new ones

[TFR]

Hi all - my friend has an E32 730 - I am 99.9% sure it has a blown head gasket - I am also pretty sure that the head will have rotted out coolant passages (he ran plain water for many years) - my question is will a cylinder head from a 735 fit ? - or ones from earlier (or later) models ? Cheers. Also will I need to get new head bolts ?

Hi, had exactly the same problem with running plain water. My gasket was really rotten rusty around the small coolant holes, but it should not necessary have damaged the head as it is made from aluminium. The other thing is that due to lots of rust in passages cooling performance could decrease and cause any possible overheating damages. And yes B35 head fits onto B30 motor (did it myself 2 weeks ago) it works but is not recommended as bore diameter difference is 3mm. If necessary I have photos of the process.
You should at least clean the old head bolts very thoroughly or better buy new ones.