Are 94's really that bad?

[John N]

Both Gene Berg and John Conally recommend against their use, yet they still sell them "for those customers that have to have them" I got a set for dirt cheap. Should I bother? Should I just stick with the 90.5's.
[/i]

[500LbGorilla]

??? John's got nothing against 94's that I know of.

Berg on the other hand, has something against a lot of things that are today mainstream products and principles. They still turn out a great product.

94's work fine. Just don't expect it to run super cool, and don't expect 100K miles out of them.

[neil68]

ACN website says that you can expect about 50,000 miles from Mahle 94's and Berg's tech book says 25-30,000. Another supplier says 40,000-60,000, etc.

My last set of 94 Mahles were out-of-round in 23,000 miles in my '69 Westy. This topic has been re-hashed a thousand times on internet forums and the general concensus is that 94s are more durable than 92s, but not as durable as 90.5's.

Therefore, you need to define your goal...are you trying to stuff large valves into the heads eg. 44 x 37, where a 94 bore may be better or are you trying to get 100,000+ miles out of the kit. Personally I believe that the ACVW already has a plenty large bore at 88 or 90.5 and needs to be stroked instead...

Some will use the 94 Mahle cylinders, but use different pistons for racing. Do some internet searches and you'll find a myriad of information, none of which will help you make a definitive decision!

One new wrinkle, is that you can get 94's that are machined for the 90.5 crankcase holes...so, you can try using the 94's and if you are not satisfied with the long-term results, then you can install 90.5s on your next rebuild...the best of both worlds!

Neil.

[stealth67vw]

My last set of 94 Mahles were out-of-round in 23,000 miles in my '69 Westy. Neil.

I wouldn't run 94s in a Heavy Type 2 or Type 3 and expect the same results as running them in a Type 1

[neil68]

stealth,

what's the difference whether 94's are used in a beetle or a bus? Either the product is durable or it isn't

Anyway, that was just one example. 90.5's will last well over 100,000 miles just like stockers (my last two daily driver Beetles, when they were my sole method of transportation, went past 100,000 miles with 90.5s... a great big bore kit IMO). If you plan to put 20,000 a year on a daily driver I would still go with 90.5s.

I have only seen one other internet post where someone claimed 70,000 miles out of some 94s in a beetle, so I guess it's possible...perhaps they were a very conservative driver.

I guess that's what forums are all about...varying experiences...

Neil.

[MinamiKotaro]

The 94mm pistons and cylinders on our VWs have lasted many years and many hundreds of thousands of miles with zero problems.

Dad's 1915 screamer: circa 1983 - current
My 1915: circa 1990 - 2004
Papaw's 1915: 198? - current

All were daily drivers for years and years. Dad's 1915, still with those same 22 year-old 94mm barrels and pistons, is now my turbo engine.

All those engines were run very hard every time they were started, and all three still run great. (Excepting my 1915 with its worn out crank bearings.)

[turboblue]

what's the difference whether 94's are used in a beetle or a bus? Either the product is durable or it isn't

So you don't think there is any difference in the load applied?
A somewhat aerodynamic beetle weighing 1900# vs. a shoe box weighing 3000#.
Load does affect longevity.

[neil68]

...can you be more specific about the "hundreds of thousands of miles" that you have gotten from 94's. What are the exact mileage figures for each set of 94's? I would be very interested to know...

Thanks,

Neil.

[Bruce2]

The 94mm pistons and cylinders on our VWs have lasted many years and many hundreds of thousands of miles with zero problems.

How many re-ring jobs were performed over those hundreds of thousands of miles?

[rcb78]

I'll add,,, what are the leakdown numbers? Mine were OK at 20k, but I couldn't see going past 40k unless I just didn't care. --Ryan

[MinamiKotaro]

...can you be more specific about the "hundreds of thousands of miles" that you have gotten from 94's. What are the exact mileage figures for each set of 94's? I would be very interested to know...

Thanks,

Neil.

Don't know for sure, but I put over 100,000 on mine in ~6 years before I got a different car (with a heater). I still drove the Bug three or more days a week in the warm months.

Papaw's and Dad's easily had more, many more, miles than mine.

How many re-ring jobs were performed over those hundreds of thousands of miles?

Mine: none
Papaw's: none
Dad's: one (too many 7000RPM shifts)

[harleyxl95]

I have a 1250 lb rail that i run on the street. I have a 2276 cc motor with 82 mm forged crank and 94 mm mahle piston-cylinder set with total seal rings. The engine has 35,000 miles on it and still runs like new. I run it exclusively on 15 W- 50 Mobil I and use synthetic gear oil too. I don't run a doghouse cooler like Berg suggests. My engine is run in an open compartment which probably keeps things much cooler. I run a 1 5/8 " cerramic coated header from EMPI with dual 40 dellortos. CR is probably about 8:1. Asked my builder to keep it driveable and durable. Used a few extra head spacers. Really love the torque it provides in such a light vehicle. Can take any hill with no downshifting.

Paul

[Guest]

Both Gene Berg and John Conally recommend against their use, yet they still sell them "for those customers that have to have them" I got a set for dirt cheap. Should I bother? Should I just stick with the 90.5's.
[/i]

Due to less fin surface area because of bore size cylinder will run
hotter. To help prevent cylinder warpage just lower the compression.
7.2 works great.