dillon410021

I know the 944 motor came from the 928 motor but are they identical?

Was curious if your could take the 944 turbo rods and pistons and build a 928 motor and do a big turbo or twin turbos.

Never seen it done so I was curious.

Humboldtgrin

No. The 928 rods are different widths and height then the 944 rods. But you can still build a 928 twin turbo. Best company to talk to would be 928motorsports.com that I know of for 928 mods. http://www.928motorsports.com/parts/...aft_keyset.php

Raceboy

951 pistons have been used on 928 build before, no problem with that. But not with early motoros that had smaller bore size..

V2Rocket

Yes, guys use 944/951 pistons in their 928 engines frequently as the bore and stroke is the same in their 5.0 engines.

The 928 rods are the same length and dimensions as the 944 rod, except for on the big end where they are machined with an "offset" of a few millimeters because 2 rods share a crank journal.

Some guys have used 2 sets of 944T rods (since they are very strong) and machined them to fit the 928 crank.

The only issue is that the 928 has a 2mm higher deck height than the 944, so at TopDeadCenter, your 944 pistons will be 2mm shy of the 928 block deck, so you will have lower CR...but a lot of valve clearance!

Paulyy

Don't understand with all the work making the 951 rods fit, shouldn't you just buy a set that's made for the 928 that's lighter and stronger and also not 25 years old

V2Rocket

You know how expensive aftermarket rods are for the 944?
Imagine paying twice that

The 951 rods are much stronger than anything the 928 was ever fitted with, and in a 928 engine they will see less stress per HP because twice as many rods to share the load...

Paulyy

expensive? that's the price you pay for owning such car.
I wouldn't go all that way building a 928 engine to put in used rods from a car with who knows how many miles and condition of them ect.

Raceboy

Yeah, that rhetoric...

Some may consider my budget 2.5 16v turbo build also nonsense ("why own such car etc") yet it works that way and some people succeed and some people don't.

You know you can check the rods for hairline cracks etc before putting them into engine, right?

V2Rocket

I wonder if shot-peening or other stress-relieving methods would be effective on "rejuvenating" tired, old (but intact) rods?

odonnell

Annealing would probably help, removing internal stresses. My understanding of shot peening is that it cold works the outer surface, making it harder and less likely to crack (entire surface is actually slightly in compression).