Was the B20 marine version (A130 I think) ever made as a stroker version. Was it in anyway different to the street version?

Also, would a 6 or 8 bolt crank be better to use as a basis for a high reving race motor.

Thanks All!
--
Alex Shevlin (Sydney): '72 144S, '81 244GLE, '81 244GL, '01 V70XC

The 6 bolt motor is reckoned to have stronger con rods which are also significantly lighter, if you are really going to rev it, you will need custom forged pistons anyway, B21 pistons are not really up to the job unless you can find turbo types, the B21 M rods from about 1980 are considered stronger but just as heavy as earlier models. I am in the process of putting together 2150cc kits for 6 bolt B20's at very reasonable prices, however these won't really be suitable for racing either.
IMHO the best economical setup is a 75 8 bolt bolt with 6 bolt guts and custom pistons for high revs.
Cheers
Hans
Katikati
New Zealand

That should be 8 boly block of course

8 bolt block!!!!

So all the guts of a 6 bolt engine can go into a 8 bolt block (I hope that came out right the first time)?

I'd probably stick to 2.0L on this engine and maybe the next on I'll increase the capacity. I was going to use pistons and rods from kgtrimmin and lighten up the valve train. Is there anything else I should be looking at before I try for high revs?
--
Alex Shevlin (Sydney): '72 144S, '81 244GLE, '81 244GL, '01 V70XC

yes, the 6 bolt flywheel, crank and rods fit into the 8 bolt block. You will want to find steel timing gears, most but not all 164's have them, also 1974 142E ( maybe), having the head ported and flowed is the most important thing with these motors, Volpro in Brisbane seems to be good at it.
Hans

To the best of my knowledge Volvo/Penta never produced any marine strokers.
The marine cams ("P" grind) were pretty much a tractor grind also.

To me, the engine, if in good condition, is as good as any, and not too many
had saltwater in the water jacket. Most had a seawater/coolant heat exchanger
with an auxiliary pump attached to the timing cover and driven by the camshaft.
Likewise I would guess that many never saw service in saltwater, being used
almost exclusively in lakes and rivers. On the other hand, all of them used
carbs so you won't find them with the "E" and "F" heads. I don't know if the
later carbureted marine versions had bigger valves like the FIs or not. Perhaps
a glance at the marine microfiches could shed some light on this but you would
have to compare P/N between the marine and automotive versions to tell that way.
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma

stay away from penta engines, salt water does bad things to steel. an 8 bolt crank will Behoove the racer, but don't worry about finding a 74/75 b20 just take the crank from a b21. as for boring any 72 and up block should do.

There isn't anything funny on the front end of a B21 crank?

As for stroker cranks, www.kgtrimning.com sells them. Reground to 86 mm stroke, rehardened, balanced for ~$650. Combine with 92mm B21 pistons for 2.4 liters. Of course, then you'll need better breathing to utilize that extra displacement at anything other than low rpms. Cam, head work, exhaust, carbs.....

Is there somthing strange about the front of the b21 crank?

I was asking, not obliquely referring to it. I just assumed that the front of the crnak would differ on a B21 because of the cam belt gear - but I gather that is just built into the pulley?

Volvo surprises me like that sometimes. Sometimes parts that look alike and have no reason to be different are different, and sometimes parts that have every reason to be different aren't.