Crank DPR vs. Bergman

[Baddvw]

Hey guys, I am looking into the differences between the DPR full-circle crank and the Bernie Bergman super-lite full circle cranks, I have heard from the fellow buggy riders swears that the Bergman cranks are the best because of the lightweight and yet the strongest you can buy, they said the throttle response is unbelievable.  I called Bergman myself and he said that he does not make them anymore because it foams the oil up and the DPR cranks is too heavy because they are not lightened like Bergmans cranks, I am just curious because I will be running a 90mm crank in the future because of the sheer torque they produce and that is very good to have in the woodsbuggy. Thanks, Chad

[JVance]

I can't help but tell you that every time you post up a good piece of lore from the 'woods buggy' community, I get a good laugh. Between running high-lift cams with single valve-springs, 1.1:1 ratio cams with 1.4:1+ ratio rockers, and now Bergman cranks being the "lightest and strongest" cranks you can buy, you guys are pushing the envelope of contradiction without a solid shred of evidence to show for it.

As far as why Bergmann is no longer making full circle cranks, I was under the impression that he sold off the tooling to make cranks. Is this not correct? Is he still making cranks? There's a difference between not making cranks any more "because it foams up the oil" and because he "no longer has the machinery to make them". The latter is an appropriate explanation; the former is a good story that gets circulated around a closed group of enthusiasts.

What are the differences between the two? The counterweights on the Bergmann full circle crank is drilled full of holes; the DPR crank is not. While some will dispute the reasoning for using a full-circle crank, if you are planning on using one based on a German core, then full-circle counterweights are necessary to provide the strength and rigidity that a welded 90mm crank will inherently lack. If you want the strongest 90mm crank you can buy, look into Pauter, Moldex, M-Spec, or Scat.

[cal 67]

I believe any light crank will do what your say the Bergmann crank does. Use a race weight DPR crank with a T4 center main or get a SCAT Superlight.

Is it just me or does a VW main 90 crank seem scary?

[Baddvw]

JVance, I wish I can prove to you that there are a few buggies in KY that has been running 2498cc with Bergman cranks and some with DPR cranks with W-110 and W-120 Engle cams there is one that is running 1.5:1 roller rockers on a W-110 cam, these have been proven by other drivers that you need a cam like the W-series and use the high ratio rockers does work and I have not seen the internals of the engine myself, they need the low duration cams for the low end powerband and the high lift to widen up the powerband, the W-110 shows that they produce the best powerband from 1500-5500 rpm with only 1.25 rockers and they need more lift to increase the 5500 range into the 7000 or up like 1500-7500? How can the W-series with hi-lift rockers tear the heads and the lifter bores up? As long as the lift stays the same AT the cam, what difference does it make as long as you got the heads set-up properly to handle such big lifts? I now have a 2387cc running awesome with a FK-43 cam and it was a great choice by your help and opinions, I was just being curious about these other subjects just for researching because you guys on the West Coast has been running VW's on the drag strip and streets for a long time and knows what and what not to run, remember, we are all about torque not HP and sometimes it takes a cam like a FK-43 or W-110 to produce the powerband we need to make successful trail buggies. I know that you guys does not do anything that we do on the East Coast in the woods, but all I can tell you is that I am just slowly trying to improve myself until I cannot get any better than the previous setup. We cannot run the FK-87, FK-89 cams because of the high duration and the powerband is too high in the range when we need the bottom end, I have seen it with my own eyes that they can start at the bottom of any hill with no room to make a run at it and takes off like a rocket and nope they are not revving the engine and dumping the clutch either, they just barely get the buggy rolling then smash down on the throttle, I bet the drag cars cannot do that because of the cams they run requiring the engine to be revved at 7000 rpm then dump the clutch. Sorry for posting such "funny lores" on here, but I am just looking for answers. Thanks, Chad

[Baddvw]

I was told that they run all type 1 mains on their 90mm cranks, it was not necessary to run the type 4 center main unless you drag race the engine all the time like in the 7500-up range.

[maui]

I ran a B/B 86 F/C crank wit no holes for make um lite for about 10 years with no problems with FK87 and big heads and no bog action at lowend. About 50,000mls on it with regular service and the mains are stuyet good and the rods need to cut once. Maybe from the choke burnouts with DOTs and 7 to 8 grand revs. If he stuyet makes those cranks i would get me one 90 also but O well.

[Baddvw]

I ran a B/B 86 F/C crank wit no holes for make um lite for about 10 years with no problems with FK87 and big heads and no bog action at lowend. About 50,000mls on it with regular service and the mains are stuyet good and the rods need to cut once. Maybe from the choke burnouts with DOTs and 7 to 8 grand revs. If he stuyet makes those cranks i would get me one 90 also but O well.

That's good to hear that you have no bottom end loss, but are running 48 IDA's? I cannot run such big carburetors because the response in the mid and high range will be too quick and will cause our rear tires to spin out too quick and cannot get any traction in the dirt, most woodsbuggys run 44 IDf's and 40 Dellortos and they produce plenty of power and it is very controllable as well.

[sinikl]

between kehau's pidgin (which i love) and baddvw's weird phrasing and no punctuation (huh?), all this thread needs is doug berg to jump on IN ALL CAPS AND IT WILL BE COMPLETE.

[jeff denham]

hands down DPR ALL THE WAY thats the only crank guy i will give my dead presidents to. and jose is a great down to earth guy with NO TUDE.  JD .

[Joel Mohr]

X2!

[toysandprojects]

     DPR Jose is good to me.

[garyj]

Agreed!

[BusterJohn]

DPR hands down!!!

[2DubTech]

Had a CB 82 crank that got jacked up in a motor blow up and Jose fixed it right up and turned it to an 84. Good guy, very easy to talk to and prompt with service.  He is close enough for me to drive to also.  Good work and service I would recommend for sure.

[Yamaducci]

   Hey guys I am new to the forum but wanted to chime in since I am rebuilding a Bergman 2449 cc right now for the 3rd time! I won't go into all of the reasons why it needs to be rebuilt again with less than 500 miles on it since it was originally built by bergman ( unless you ask) but I will say that the 90mm F/C crank is nice with a few draw backs. BTW I believe; but am not positive that the Bergman 90mm F/C cranks were produced by DMS. That said. it has been the strongest part of the 2449 cc package. The down side is that the crank is just too big for the case with all of the counterweights. Like Bergman said the "Oil Foams up". That is no joke. This crank should be marketed for use only with a dry sump oil system. Period! You can not run this combination down the highway over 3000 RPM's and expect to have any oil pressure after about 10 minutes....AND the blow by is outragious! Oil finds it's way out of everywhere. And, Yes,  I also have it vented in 3 locations and to the turbo's air cleaner. I just purchased the Bugpack Dry sump and CB Performance tank to help resolve these issues.
  Next issue is clearancing The case has serious clearancing requirements that weaken the case. Not only do you need to clearance the cylinder side of the case but also the top and subsiquently the cam (bottom).
This should be considered if you want your engine to live.
  The next thing is cam clearancing. The cam needs to be machined down to half it's original diameter in several locations to clear the weights Although I have wiped the original cam lobes on the first build the cam did stay in one piece. I believe I had some luck there.
Finally if you are considering Bergman to build your engine not just provide the parts. Ask to prove he didn't use everything else chinese.

[JVance]

...

[Yamaducci]

JVANCE-
Forgive me, Not sure what
"...." means?

[Sam]

Coming from the dune buggy comunity, I would like to sincerely warn anyone from taking campfire advice at the dunes, hills, ect. Lots of guys get away with stuff that most of us here on CLF would deny even works. i used to do some scary stuff myself so I speak from experience.

Its funny how redneck performance can spread like wildfire when someone claims it works, I used to hear all the time that you could run a FK89 with 15:1 compression on AV gas and it makes great bottom end torque, especially with stock heads, a solex 34, and 1 7/8 exhauist.  I'm slightly exagerating, but not too much.

Not to offend anyone, but be carefull about what you believe especially in the VW offroad community.

[Sam]

I run a Scat Pro-comp 84mm wedgemated, ect and it does rev great and is very responsive to throttle even with 48 dells

http://www.thesamba.com/vw/classifieds/detail.php?id=788882

 

[JVance]

JVANCE-
Forgive me, Not sure what
"...." means?

It means, "instead of deleting my post, which I cannot do, I can simply delete the words and replace it with ... "

[Baddvw]

I am not trying to start anything out of the subject, it amazes me that they are performing very well am I am trying to get some answers, I cannot prove otherwise unless I see inside their engine myself when one is taken apart, but that never happened yet, they will not tell me directly to my face what they are running for sure, I am just saying that's what I hear, I did not go that route because I am not even sure if it works myself, I just went ahead and put mine together as a 2387cc with FK-43 cam, ported and polished Street Elimininator heads, Pauter 1.4 roller rockers and so on, this buggy of mine runs like a raped ape and am running a 091 bus transmission with all weddle gears, including the r&p, and it will go and has tons of torque whenever I need it. Sorry if I started this "wildfire" because of the redneck engineering that I have around my woods, but you will be amazed on some of the things we do and I guarantee you that if someone takes their $100,000 sand rail in the woods, it would not last 100 yard into the trails, and we even have "chaindrive" railbuggies in Tennessee that has 600 hp small block chevy engines that runs on propane and uses and Audi automatic transmission and they can climb a wall that dirtbikes can't even touch. I knew that this was gonna happen on the differences between us, again sorry if I offended anybody.

[Baddvw]

Coming from the dune buggy comunity, I would like to sincerely warn anyone from taking campfire advice at the dunes, hills, ect. Lots of guys get away with stuff that most of us here on CLF would deny even works. i used to do some scary stuff myself so I speak from experience.

Its funny how redneck performance can spread like wildfire when someone claims it works, I used to hear all the time that you could run a FK89 with 15:1 compression on AV gas and it makes great bottom end torque, especially with stock heads, a solex 34, and 1 7/8 exhauist.  I'm slightly exagerating, but not too much.

Not to offend anyone, but be carefull about what you believe especially in the VW offroad community.

I have heard that my self too, but it has not been confirmed and alot of high performance VW engines in the woodsbuggy community has at least dual carbs and runs on pump gas, the more C/R, the higher the octane is required and I know that for a fact, I am running 12.5:1 C/R now and am running on VP-c16 race gas and also have Weber IDF 44's with the CB Performance upgrade kit. I am glad I went with the FK-43 cam and it runs great, all I can say is run whatever you know what works, not the BS that I was saying the KY boys do, they have to run big cams for sure, just don't know what.

[Ohio Tom (DdK)]

I have been watching this one for a while.
I am an East coaster. I build hot street and Drag motors for folks in 2 states.
Occasionally, I'll do an Woodsbuggy motor.

I have a few things to add:

When going over 84mm stroke you run into several issues.
1. longer crank throws mean more cam clearance issues. Cut too much and the cam will break (seen it happen).
2. depending on teh crank manufacturer, you may be limited on "cam lift" as the cam lobes may hit the crank throws. There is no real clearancing you can do to solve this problem. You have to go with a lower lift cam (and use higher ratio rockers) or go with a smaller base circle cam. (This  wears out the lifter bores faster as the lifters are haning out farther).
3. Journal overlap goes away. The crankshaft looses alot of strength, especially in the center main area (reason for T4 center main mod). This is why the "big boys" by higher quality crankshafts to get back some lost strength.

4. welded stock cranks should be wedgmated. The dowel fit is just too loose to stay together otherwise.
A good aftermarket crank will have good press fit dowels that can be run w/o a wedmate. (do it myself on many motors).

It is for these reasons, I do not like building motor with stroke more than 84mm.
Rather I would recommend staying with a 2276, 2332cc's for longevity.
If you really  must have more power, then build a low compression/cool running 2110cc with a small turbo on it. You will blow away everyone with torque to spare.
Plus, if you blow it up, it will be cheap and easy to fix.

I have some personal experience with using high ratio rockers on W series cams... It will beat up the valve trane fast. Also, you had better have some really strong valve springs to keep it all under control. Valve float is common with setups like this. you may not notice much at first, but valve float will eventuall lead to pulled retianers and dropped valves. Pitted lifters, worn out cams...
I learned the hard way to stick with the manufacture recommendations. There are plenty of cams out there that will provide the high lift/short duration you are wanting. While still staying withing the manufacture recommendations. This is important to get right if you want your motor to last more than a few runs a summer.

Oil foaming/blow-by.
Over the years I have figured out alot on this subject.
1. proper case breathing. The 1-2 cyls are going up when the 2-4 cyls are going down. There is a back and forth air movement from the front of the case to the rear of the case on every revoultion. I do ALOT of "case porting" on stroker motors. This makes HUGE diffences on what comes out the breather vent.
2. ring seal. VW rings will go bad the first time you overheat the motor. Hone and re-ring is the only solution. Don't forget to set your ring gaps properly.
Poor oiling will cause the cyls to become "suffed" with grooves that tear up ring seal fast too.
Warm up the motor before spanking on it.
I also recommend for offroading, to hone out your cyls to at least .006" clearance to avoid scuffing.
I have run motors with .018" cyl clearance and have no problems with ring seal.
3. Oil foaming is usually from lack of warmup, and/or the use of oil that likes to foam. I have tried many oils in my race motors over the years. I have discovered that some oils foam more than others. Mobil 1 synthetic is one of the worst I have seen.
Brad Penn is good. Shell Rotella-T seems good too.
Foamy oil wil not only fill your breather up, but it will also take out your rod bearings.
 Foaming = Bad... Un-K...

[Sam]

I have heard that my self too, but it has not been confirmed and alot of high performance VW engines in the woodsbuggy community has at least dual carbs and runs on pump gas, the more C/R, the higher the octane is required and I know that for a fact, I am running 12.5:1 C/R now and am running on VP-c16 race gas and also have Weber IDF 44's with the CB Performance upgrade kit. I am glad I went with the FK-43 cam and it runs great, all I can say is run whatever you know what works, not the BS that I was saying the KY boys do, they have to run big cams for sure, just don't know what.

The engine you described for yourself sounds like a good engine not a hack job. You like that compression don't you, I love compression even at the cost of high octane fuel (C12 for me)  Not all offroad VWs are bad, but they are the main source for the stereo type of the "unrelaible" VW .  I just love blowing the wheels off the 100K sandrails with my VW, I can't imagine how fast I could make a midengine VW rail go. 

Guys used to gripe about not being able to get bottom end torque from the 86+ cranks, but I think the new FK4_ cranks help that alot with their big lifts and modest durations.

A well built 2000cc vw will out perform most any hackjob 2500cc vw engine, you will be happy you bought good heads, a good crank, the right cam IMO for your application. I bet your buggy is fun to drive, what does it weigh?

I have been watching this one for a while.
I am an East coaster. I build hot street and Drag motors for folks in 2 states.
Occasionally, I'll do an Woodsbuggy motor.

I have a few things to add:

When going over 84mm stroke you run into several issues.
1. longer crank throws mean more cam clearance issues. Cut too much and the cam will break (seen it happen).
2. depending on teh crank manufacturer, you may be limited on "cam lift" as the cam lobes may hit the crank throws. There is no real clearancing you can do to solve this problem. You have to go with a lower lift cam (and use higher ratio rockers) or go with a smaller base circle cam. (This  wears out the lifter bores faster as the lifters are haning out farther).
3. Journal overlap goes away. The crankshaft looses alot of strength, especially in the center main area (reason for T4 center main mod). This is why the "big boys" by higher quality crankshafts to get back some lost strength.

4. welded stock cranks should be wedgmated. The dowel fit is just too loose to stay together otherwise.
A good aftermarket crank will have good press fit dowels that can be run w/o a wedmate. (do it myself on many motors).

It is for these reasons, I do not like building motor with stroke more than 84mm.
Rather I would recommend staying with a 2276, 2332cc's for longevity.
If you really  must have more power, then build a low compression/cool running 2110cc with a small turbo on it. You will blow away everyone with torque to spare.
Plus, if you blow it up, it will be cheap and easy to fix.

I have some personal experience with using high ratio rockers on W series cams... It will beat up the valve trane fast. Also, you had better have some really strong valve springs to keep it all under control. Valve float is common with setups like this. you may not notice much at first, but valve float will eventuall lead to pulled retianers and dropped valves. Pitted lifters, worn out cams...
I learned the hard way to stick with the manufacture recommendations. There are plenty of cams out there that will provide the high lift/short duration you are wanting. While still staying withing the manufacture recommendations. This is important to get right if you want your motor to last more than a few runs a summer.

Oil foaming/blow-by.
Over the years I have figured out alot on this subject.
1. proper case breathing. The 1-2 cyls are going up when the 2-4 cyls are going down. There is a back and forth air movement from the front of the case to the rear of the case on every revoultion. I do ALOT of "case porting" on stroker motors. This makes HUGE diffences on what comes out the breather vent.
2. ring seal. VW rings will go bad the first time you overheat the motor. Hone and re-ring is the only solution. Don't forget to set your ring gaps properly.
Poor oiling will cause the cyls to become "suffed" with grooves that tear up ring seal fast too.
Warm up the motor before spanking on it.
I also recommend for offroading, to hone out your cyls to at least .006" clearance to avoid scuffing.
I have run motors with .018" cyl clearance and have no problems with ring seal.
3. Oil foaming is usually from lack of warmup, and/or the use of oil that likes to foam. I have tried many oils in my race motors over the years. I have discovered that some oils foam more than others. Mobil 1 synthetic is one of the worst I have seen.
Brad Penn is good. Shell Rotella-T seems good too.
Foamy oil wil not only fill your breather up, but it will also take out your rod bearings.
 Foaming = Bad... Un-K...

This is a great post, I used to have trouble with oil gunking in the engine from getting pretty warm and then cooling over and over. oil was valvoline racing 20-50, temps were 100C then I would let it cool, usually shooting to keep it about 80 degreesC, but its amazing how fast the VWs cool off on a breezy day.  I switched to Royal Purple and don't get hot anymore, its amazing, no foam also. I also like to do some porting, but my version is more like aggressive deburring, and I like to run a crankcase vent from where the stock fuel pump goes.

[Baddvw]

A well built 2000cc vw will out perform most any hackjob 2500cc vw engine, you will be happy you bought good heads, a good crank, the right cam IMO for your application. I bet your buggy is fun to drive, what does it weigh?

My buggy weighs around 1450 without me in it, I have not verify this yet, I will borrow a set of race scales from a local late-model shop and see, I love the power it produces and the heads help ALOT, the fuel is around $9.00/gallon since I bought a 55 gallon barrel of it at once, it is an awesome machine and it rides like a dream thanks to the coil-overs and I think I could take them other buggies that runs the "2500cc" engines, it just depends on how it does at the time it happens. Also, I am running the XRP Royal Purple racing oil as well (20w-50) Thanks, Chad

Here is a picture of the buggy....





I am no longer running the boggers, I am now running Firestone 23 degrees tractor tires (31x15.50x15)

[Busstom]

It means, "instead of deleting my post, which I cannot do, I can simply delete the words and replace it with ... "

Ahhhh....interesting...but, how did you get rid of the "Last Edit...."   text that automatically appears at the bottom of your post??

Or did you simply abandon your post before actually "posting" it? 

[JVance]

Ahhhh....interesting...but, how did you get rid of the "Last Edit...."   text that automatically appears at the bottom of your post??

Or did you simply abandon your post before actually "posting" it?  

If you edit the post soon enough after posting it, the last edit text will not show up.


[edit 1]
[edit 2]
[edit 3]

[bugnut]

Thinking about Bergmann, I can't help but wonder what he was thinking back in the '80s when he advertised all those engines with the crapty angle-cut fan shrouds and permacool external coolers fastened to the back over the fan inlet...tsk, tsk.

[Sam]

Thinking about Bergmann, I can't help but wonder what he was thinking back in the '80s when he advertised all those engines with the crapty angle-cut fan shrouds and permacool external coolers fastened to the back over the fan inlet...tsk, tsk.

LOL, hey they aren't all bad. Works fine on a buggy, but yea go ahead and blow hot air on your jugs! My dad had one when I was a kid, I ran it a while untill I had overheating problems an a high compression 1776.
I love bergman's sidewinder exhaust for dune buggys, looks super cool.

[1836vw]

I can see that most big VW motor builders are forced to build their own crankshaft.  Maybe you need to ask Bernie and Berg about why they had to build their own crankshafts. 

[Banzai KG]

I have been watching this one for a while.
I am an East coaster. I build hot street and Drag motors for folks in 2 states.
Occasionally, I'll do an Woodsbuggy motor.

I have a few things to add:

Oil foaming/blow-by.
Over the years I have figured out alot on this subject.
1. proper case breathing. The 1-2 cyls are going up when the 2-4 cyls are going down. There is a back and forth air movement from the front of the case to the rear of the case on every revoultion. I do ALOT of "case porting" on stroker motors. This makes HUGE diffences on what comes out the breather vent.
2. ring seal. VW rings will go bad the first time you overheat the motor. Hone and re-ring is the only solution. Don't forget to set your ring gaps properly.
Poor oiling will cause the cyls to become "suffed" with grooves that tear up ring seal fast too.
Warm up the motor before spanking on it.
I also recommend for offroading, to hone out your cyls to at least .006" clearance to avoid scuffing.
I have run motors with .018" cyl clearance and have no problems with ring seal.
3. Oil foaming is usually from lack of warmup, and/or the use of oil that likes to foam. I have tried many oils in my race motors over the years. I have discovered that some oils foam more than others. Mobil 1 synthetic is one of the worst I have seen.
Brad Penn is good. Shell Rotella-T seems good too.
Foamy oil wil not only fill your breather up, but it will also take out your rod bearings.
 Foaming = Bad... Un-K...

Regarding about the Bergman crank, I do recall their lightweight crank has holes in it which I would think would cause oil to slosh through the holes and cause foaming compared to a solid knife-edged crank. Would that make any sense about the oil foaming?
Did a "search" for Bergmann Crank and found this:
Largest stroker crankshaft in stock T1 case? - http://www.thesamba.com/vw/forum/viewtopic.php?t=333988

[orangepeel]

And look at the "RTV" on the case halfs.

[Kafer_Mike]

And look at the "RTV" on the case halfs.

I think that's blue paint on the case...

[Vdubwizard]

I've been running B.Bergmann cranks for years starting with a 90mm lite weight and using a slip-in oil windage tray and 30 wt Valvoline,
never ran into oil spray, foam, or bearing starvation. I now have a B.Bergmann Full circle lite 84mm w/94mm p&cyl's, 11.1 to 1 Compression ratio, (was 11.5 to 1) The rods are 5.7 Chevy.  But no need for pure race fuel! Just been running 91 Octane w/ some moroso booster, or some 110 Can booster for a few points to ...95 Octane. Some fake lead additive, never pings, Very fast w T-2 trans close ratio and 4.87 R & P. Fk10 cam w/1.4 rockers 42 X 37.5 Ported & matched manifolds, smoothed chambers and unshrouded valves, 48 Dells, 010 Dist., w/Blue Coil. Would like to get a fifth (5) gear. Tops out @ around 80-85 depending upon RPM.   Full cage, body, pan Baja Bug not light but fun!!!  Gary