Building a high revving engine with a stock crank...

[Diederick/DVK]

Alright, I have to post this here as I've spoken about this with quite a few people on here now.

If you were to build say a 1776/1835/1914 with a long duration cam etc etc, upping the powerband to around 6500/7000rpm.
Could you use a stock VW crank? Taking into account that it is 8-dowelled and the shortblock will of course be fully balanced (PP, clutch, flywheel, crank, rods, pulley)

Some say you can without worries (please speak up guys)
And some people even get a c/w crank when opting for a w100 etc.

Earlier on today, I again read the "Building a 1700cc Street Screamer" article in the Feb 76 HotVW, where Dean Kirsten has his 1679 IDA-ed motor build with a stock crank and all the other great 70s-spec stuff. The engine produced 130hp at 6000rpm but it had quite a bit left, though they didn't wanna push it that far yet.

Anyway, i'd say fire away... 

[stealth67vw]

I say if your going to dump money into building a hi revving engine, why use a stock crank. It will pound out the center main in short time. If your going through the trouble of 8 dowelling and balancing it use a  c/w crank. I use them even with a stock cam, in stock engines. They run so much smoother.

[Shubee2 (DSK)]

I say if your going to dump money into building a hi revving engine, why use a stock crank. It will pound out the center main in short time. If your going through the trouble of 8 dowelling and balancing it use a  c/w crank. I use them even with a stock cam, in stock engines. They run so much smoother.

Same thing I told you Diederick You need to build a stong Bottom End or A rod will take the case out..

[Lee.C]

Like I told you dude - use a CW crank they Rev sooooooo smoothly it will work out cheaper in the long run BUT I would still have it all balanced as you planned 

[Robert]

I have built two strokers with welded stock cranks, without counterweights. The last one is a 78x94. I had that case shuffle pinned and used an equalizer pulley and had it balanced. I used it for drag racing and shifted at 7500 rpm. I built it on a small budget and I think it worked for me. I am not saying it is the way to do it but it also depends on how you are going to drive it.
/Robert

[Shubee2 (DSK)]

I have built two strokers with welded stock cranks, without counterweights. The last one is a 78x94. I had that case shuffle pinned and used an equalizer pulley and had it balanced. I used it for drag racing and shifted at 7500 rpm. I built it on a small budget and I think it worked for me. I am not saying it is the way to do it but it also depends on how you are going to drive it.
/Robert

I have never seen a 78mm Stroker crank without Counter weights??? most of them Forged these days without being welded. Why  would you want to beat the case to death?  shifting the load of the crank and rod assy. Counter weights are added to  Counter Balance the crank so the load stay's centered (kind of like a full Circle) and is way smother running threw the RPM range

[stealth67vw]

Hot VWs did a build in the 80s where they built a 2180 with a welded non counterweighted crank. It was destined for a Baja 1000 car so it didn't have to last long. The article said they rev up quicker due to less rotating mass.

[Robert]

My crank was welded and stroked in Finland. They made a lot of them in the 80´s for rallycrossing. I got it very cheap from a neighbour and used it in my race engine. I have another crank like that with 87mm bore in my street car that has been running for many years. It is not a daily driver but I think I have put around 50000km:s on it. I don,t rev it 7000rpm all the time though.

[Sarge]

The motors we built in the old days pretty much all revolved around stock crank and rod combos.  Only a very few of those I was around had the cash to spend on a counterweighted crank.  We built 1600's, 1700's and 1835's for the most part.  Most of those engines used either an Engle 110, 120, 125 or 130 cam.  Flywheels generally weighed in at 12-14 lbs.  A lot of us ran power pulleys back then, too.  As for oil coolers, I have a hard time recalling anyone using much more then a stock, in the fan housing, cooler.  As for ported and polished heads, those of us that could afford them usually ran 40mm X 35.5mm valve size.  A lot of these combos ran single two barrel (Holley Bug spray or Zenith), Solex 40P11, or 48 IDA's (with 37mm venturies).  Exhaust size was 1 3/8", 1 1/2" for the most part.  I built a number of these motors over the years and, aside from breaking a few ring lans on cast 92's from too much compression, had very good luck with all of them.  Bearing in mind the quality of fuel these days, I'd steer clear of high compression...maybe 8.0:1 or 8.5:1.  I 'd stick to 1.1:1 rockers when using the cams I mentioned, too.  Some of these combos do much better with close ratio gears (125, 130).  I will say that I never raced on slicks back in the day, just 165 X 15 Pirelli's, so that may have saved on some engine failures.  Just my two cents worth...  Good luck with your build!

[The Ideaman]

A year or so ago, Daniel Hood got a bunch of parts from an old midget racer.  These included a set of Berg square ports with manifolds and p11's, and a welded stroker crank with no counterweights.  Price was right too.  Free!

[Bewitched666]

Diederick like everybody says here i would go for a c/w crank for more smooth revving and more reliable engine life.
On high rpms the c/w crank is better .

If spending all the money to built a 1776/1835/1915cc built it good with all the good components.
Je hebt er alleen maar profeit van dude.

[Diederick/DVK]

The motors we built in the old days pretty much all revolved around stock crank and rod combos.  Only a very few of those I was around had the cash to spend on a counterweighted crank.  We built 1600's, 1700's and 1835's for the most part.  Most of those engines used either an Engle 110, 120, 125 or 130 cam.  Flywheels generally weighed in at 12-14 lbs.  A lot of us ran power pulleys back then, too.  As for oil coolers, I have a hard time recalling anyone using much more then a stock, in the fan housing, cooler.  As for ported and polished heads, those of us that could afford them usually ran 40mm X 35.5mm valve size.  A lot of these combos ran single two barrel (Holley Bug spray or Zenith), Solex 40P11, or 48 IDA's (with 37mm venturies).  Exhaust size was 1 3/8", 1 1/2" for the most part.  I built a number of these motors over the years and, aside from breaking a few ring lans on cast 92's from too much compression, had very good luck with all of them.  Bearing in mind the quality of fuel these days, I'd steer clear of high compression...maybe 8.0:1 or 8.5:1.  I 'd stick to 1.1:1 rockers when using the cams I mentioned, too.  Some of these combos do much better with close ratio gears (125, 130).  I will say that I never raced on slicks back in the day, just 165 X 15 Pirelli's, so that may have saved on some engine failures.  Just my two cents worth...  Good luck with your build!

I wonder why as Sarge mentions, the guys back then could get away with stock cranks, stock oil coolers and power pulleys.
Whilst many of us these days go for c/w cranks, external oil coolers and all steer clear from power pulleys.

If I had the money, sure I would go for all of these safe options. But at the moment I'm just looking to build a fun motor for my 67. And I need to get it all done before next season, on a budget that is. So, I just wanna see what do I really need.

Secondly, it's not like I am gonna run the snot out of motor and shift at 7000 all day, I want to, but not all day long 

[Sarge]

It's not that we could "get away with"...it was all that we had.  Back then, there was not a lot to choose from, so we did the best we could with what was available.  That meant no doghouse oil coolers, no nice forged stroker cranks (only 82mm roller or cast 74 or 76mm Febi/Bilstein cranks), no forged 90.5 or 94mm pistons....  There were some nice things from EMPI but they cost big bucks....much easier and cheaper to go with the tried and true 1700 with Engle 110, IDA's and an 1 1/2" competition exhaust.  As for power pulleys, they were new and the word "power" as well as being relativly cheap...how could you go wrong??    A lot of today's mentality seems to revolve around "bigger is better" and "I've got all the latest and best shit on my motor"...when truth be told, you can still have a damn good time with an old combo from back in the day.

[Sarge]

you guys had the better gas back then too.

Yeah, and that was a key ingredient in the "recipe."  But that's not to say you can't still have a good time with a small engine.  Always try to make the most of what you build.

[Jon]

you guys had the better gas back then too.

Yeah, and that was a key ingredient in the "recipe."  But that's not to say you can't still have a good time with a small engine.  Always try to make the most of what you build.

You are talking about CR right? What static ratio would you "get away" with back in the day?

 Also the build quality aspect you guys mentions is a very interesting thing I think. "Always try to make the most of what you build" I can't count how many times I have read the sentence " I don't need to check/measure/fix that, since this aint no race engine!" Usually followed by: "its just supposed to be a warm engine in my daily driver".
Okay? So since you are going to drive it for hours and hours and thousands of K's... and not 402 meters at the time, you don't need to do it right?

Anyone who has the Bentley manual knows how much time VW spent on their engines to make them last...

[Diederick/DVK]

Again, I have to say three of my favorite motors were under 2.0 liters and oh so simple.

Did one of them include a 1914? 
I guess I'd best invest in a 69mm DPR crank then...
Anyhow, I still need to get my case measured out etc. So, we'll see how that goes first 

[Sarge]

You are talking about CR right? What static ratio would you "get away" with back in the day?

 Also the build quality aspect you guys mentions is a very interesting thing I think. "Always try to make the most of what you build" I can't count how many times I have read the sentence " I don't need to check/measure/fix that, since this aint no race engine!" Usually followed by: "its just supposed to be a warm engine in my daily driver".
Okay? So since you are going to drive it for hours and hours and thousands of K's... and not 402 meters at the time, you don't need to do it right?

Anyone who has the Bentley manual knows how much time VW spent on their engines to make them last...

Back in the day, very few if any of us "street" types cc'd combustion chambers to accuratly measure compression ratios...it was more like "take .080" out of my heads" (or .100"-.120").  I think most of us were probably in the 10.0:1-11.0:1 zone.  With cast 92's, the higher rarios resulted in ring lan breakage and excessive blow-by.  As for making the most of what you have, when you have to scrape $$$ for every part you buy, this becomes REALLY important.  I can't tell you how many guys I've been around over the years that failed to take the time first in considering their combination and then actually going on to fine tune their creation (jetting, timing, exhaust size, etc).  It dosen't stop with the engine either...had your alignment checked lately (is your car really hard to push...does it roll easy?)...looked after your brakes, changed the gear oil?  All of these need to be considered when your looking for the best bang for your buck.  Sorry about the rant...