Aussieveedubbers · Tech Talk

74 x 92 = ?

https://forums.aussieveedubbers.com/threads/51481/74-x-92

cram ·

whats the cc?
has anyone tried this combo?

PurpleT3 ·

That's 1582cc. Sound slike a strange combo, what motor has a 74mm bore?

VWCOOL ·

I think he means 92x74 - a 5mm 'stroker'...?

If so, might be better to investigate using 94mm pistons/barrels (same machining process) and keeping a standard forged 69mm crank (less cost, complexity and quality issues) for a similar performance outcome


[ Edited on 27-4-2006 by VWCOOL ]

cram ·

74mm stroke x 92 mm bore

cram ·

or 92 mm bore X 74 mm stroke!
got it right that time!

PurpleT3 ·

That's 1968cc.

cram ·

cheers

helbus ·

What size does that give us?
VWCOOL wrote:I think he means 92x74 - a 5mm 'stroker'...?

If so, might be better to investigate using 94mm pistons/barrels (same machining process) and keeping a standard forged 69mm crank (less cost, complexity and quality issues) for a similar performance outcome

VWCOOL ·

Not sure off the top of my head. Around 2-litre... 1968, 1998, 2016 and all those numbers you see now and then...

PurpleT3 ·

94mm bore x 69mm stroke gives the good old 1916cc.

cram ·

just exploring options
I have a case and heads to take 92 mm P/C
no crank or P/C though....🙁

74 mm crank shouldn't need clearencing and should just slip in

and its a little bit different !

helbus ·

What about 92 x 69mm?

cram ·

just starting to look into it...it'll be either
92 x 69 (1835) or 92 x 74 (1968)
need to buy a crank anyway!

PurpleT3 ·

Keep in mind that depending on the case you use, a 74mm crank may require clearancing of the case.

Bizarre ·

http://www.aircooled.net/gnrlsite/resource/specgeninfo/calcs.htm

here is an engine calc for these things

66deluxe ·

Don't think 76 and under stroke needed clearancing, as CB sell a drop in kit using a 76mm stroker.

hellbugged ·

cram wrote:just exploring options
I have a case and heads to take 92 mm P/C
no crank or P/C though....🙁

74 mm crank shouldn't need clearencing and should just slip in

and its a little bit different !
don't forget you could choose 90.5mm as well

johny rotten ·

cram wrote:whats the cc?
has anyone tried this combo?

Plenty of have poeple have used this combination with great results, cost is the only downfall with a short stroke like a 74, there is no quality issues , and to call a vw 74 stroker motor complex is just a croc of shit.thanks cool
:thumb

[ Edited on 28-4-2006 by johny rotten ]

cram ·

thanks for the feedback...

I like the stroker idea and have no problem with the 74 crank..it costs half way between a stock and the bigger strokes (76mm +)..

Anyway, I've been getting some quotes and cost of building a big vw does add up!!

Euro_67 ·

92mm cylinders have a thinner wall thickness than 90.5 or 94. There have been the usual debates about the thinner cylinder wall causing the engine to run too hot. 90.5 have the same size od where they fit in the case but thicker wall, so they would fit the case you have. then go a longer stroke to make up the capacity. 90.5 X 74 is 1904cc. Rod penrose had some Cb cranks at good prices

http://forums.aussieveedubbers.com/viewtopic.php?tid=50225&page=1#pid467977

Or for an even bigger stroke and capacity at a little more cost and effort try these !

http://forums.aussieveedubbers.com/viewtopic.php?tid=48937#pid456167

Bizarre ·

Just to throw petrol

You can also use a cut down 94 to fit in a case machined for 90.5-92's.

yes - it makes it very thin down the bottom, but it is really only for seating. The heat is above the piston top, and in the head.

Rimco in the states do these. I know of several motors that run these in the states and one i regularly talk to (Ryan - SBO) has been around for several years as a daily driver

Just another option

Alex Holzl ·

we built one many years ago and it was a good combo (Porsche style stroke and bore ) you can run 92s with total seal rings but thicker barrells can only be better.:bounce

Craig Torrens ·

Alex Holzl wrote:(Porsche style stroke and bore ) better.:bounce
Short stroke and BIG bore...................just like Porsche.