| Author |
Message |
Anatolviper
Samba Member
Joined: April 18, 2021
Posts: 19
Location: Rus
|
 Posted: Sun Apr 18, 2021 1:07 pm Post subject: Type4 Camshafts for low RPM |
 |
|
Hi All
Im trying to build aero-engine usins stock Type4-2000 engine (CU)
Im need to get a Higest Torque at low RPM (appr. 2700-3000)
PLEASE help me select the required camshaft from this list:
275 DURATION / .473 LIFT
272 DURATION / .430 LIFT
298 DURATION / .507 LIFT
310 DURATION / .533 LIFT
Also a desire to increase the volume of cylinders with a large bore,up to
2365CC,using stock CRANKSHAFT.
In the end I want to get about 80-85 horsepower.
I will be glad to any recommendation, THANKS |
|
| Back to top |
|
 |
Alstrup
Samba Member
Joined: July 12, 2007
Posts: 7215
Location: Videbaek Denmark
|
| Posted: Sun Apr 18, 2021 1:51 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
Hello, and welcome. "Rus".... Russia? Dobryy vecher
While the 103*71 combo is widely used I would not recommend it, especially not if the engine is to pull a bus. Just saying.
Also 85 hp - even to the wheels is easy with a 2 liter engine.
There are more than one way to get there though.
Judging from the cam specs you are looking at Scat cams, correct ? If so, there really is only one that would fit the bill fairly well. That is the C25.
_________________
https://www.thesamba.com/vw/forum/viewtopic.php?t=435993 |
|
| Back to top |
|
|
Anatolviper
Samba Member
Joined: April 18, 2021
Posts: 19
Location: Rus
|
| Posted: Sun Apr 18, 2021 2:06 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
Yes.Russia.Dobry vecher!!!)))
Thanks for recommendation!
Which combination can you recommend for me?
Unfortunately, in our country there are very few VW beetle / bus specialists.
I thought that increasing the volume of cylinders would lead to an increase in power anyway,and im dont know how else to achieve this without stress-loading the engine... |
|
| Back to top |
|
|
Alstrup
Samba Member
Joined: July 12, 2007
Posts: 7215
Location: Videbaek Denmark
|
| Posted: Sun Apr 18, 2021 2:21 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
Khorosho.
You are correct with displacement of course. But a bus has a little different power requirements as a beetle which means a higher constant load which again is not good for the large cylinders. They will leak between heads and cylinders soon. I will not say that it can´t be done, but it is NOT for beginners. If you REALLY want to go that route you might want to take a look at our Australian colleagues and how they prep the cylinders. Also a guy around here Getbackontrack.dk does it with some succes. Personally I do not like more than 98 mm bore, 100 mm max. I use modified Deutz cylinders, so that is a more expensive route.
Dependant on exactly what you want, and what options you have, one of the best easy to build and good power for the money is a 2110 cc (76 stroke and stock 94 bore) A well built 2110 can soon be very close to the same torque output as a 2366 bus engine. The 2110 is very durable, the 2366 is not, unless seriusly prepped as menthioned.
Which provins are you from?
Torben
_________________
https://www.thesamba.com/vw/forum/viewtopic.php?t=435993 |
|
| Back to top |
|
|
Anatolviper
Samba Member
Joined: April 18, 2021
Posts: 19
Location: Rus
|
|
| Back to top |
|
|
Anatolviper
Samba Member
Joined: April 18, 2021
Posts: 19
Location: Rus
|
| Posted: Sun Apr 18, 2021 2:33 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
Also there is no any problem for machining the engine case for highest bore///
Last edited by Anatolviper on Sun Apr 18, 2021 11:33 pm; edited 1 time in total |
|
| Back to top |
|
|
Vanapplebomb
Samba Member
Joined: November 03, 2010
Posts: 5411
Location: Holland, MI
|
| Posted: Sun Apr 18, 2021 2:44 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
Sounds like you have VERY low expectations for 2365cc...
A stock bus 2.0 with flat top (914) pistons will do better than 85, and have a torque peek around 3000rpm. Remember, the ‘73 - ‘76 Djet 2.0 engines were 95-100 hp from the factory.
Heck, even the bone stock 1.7 TYPE 4 Djet car engines made 82hp and peek torque at 2700rpm.
Why you would want such a big engine to do exactly what the stock engines did is beyond me.
| Anatolviper wrote: |
Hi All
Im trying to build aero-engine usins stock Type4-2000 engine (CU)
Im need to get a Higest Torque at low RPM (appr. 2700-3000)
PLEASE help me select the required camshaft from this list:
275 DURATION / .473 LIFT
272 DURATION / .430 LIFT
298 DURATION / .507 LIFT
310 DURATION / .533 LIFT
Also a desire to increase the volume of cylinders with a large bore,up to
2365CC,using stock CRANKSHAFT.
In the end I want to get about 80-85 horsepower.
I will be glad to any recommendation, THANKS |
_________________
1800 Type 4 Berrien 295
http://www.thesamba.com/vw/forum/viewtopic.php?t=487021 |
|
| Back to top |
|
|
Anatolviper
Samba Member
Joined: April 18, 2021
Posts: 19
Location: Rus
|
| Posted: Sun Apr 18, 2021 2:52 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
| ok, please advise what do I need to replace in a standard type 4 engine to get such characteristics? (High torque at low RPM) |
|
| Back to top |
|
|
Alstrup
Samba Member
Joined: July 12, 2007
Posts: 7215
Location: Videbaek Denmark
|
| Posted: Sun Apr 18, 2021 2:54 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
OK.
Those are 96 mm bore, and can be used. But if I use 96és in busses I will rather buy pistons only and bore the stock 94´s up to 96 mm. Reason is that the stock cylinders have the heat treat of many thousand miles, so they are sturdier and will stay round under higher stress.
BUT, it actually depends somewhat on which bus you have. If it is a pre 79 type 2 it should be fine to use 96 bore. If it is a T25 I would definitely recommend a 2110 or 2165 displacement instead, so you get more power where you need it.
_________________
https://www.thesamba.com/vw/forum/viewtopic.php?t=435993 |
|
| Back to top |
|
|
Anatolviper
Samba Member
Joined: April 18, 2021
Posts: 19
Location: Rus
|
| Posted: Sun Apr 18, 2021 2:59 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
| I only know that my CU series engine is from a T2 bus |
|
| Back to top |
|
|
Alstrup
Samba Member
Joined: July 12, 2007
Posts: 7215
Location: Videbaek Denmark
|
|
| Back to top |
|
|
67rustavenger 
Samba Member
Joined: February 24, 2015
Posts: 9767
Location: Oregon
|
| Posted: Sun Apr 18, 2021 3:30 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
| Alstrup wrote: |
OK.
Let me ask this way then: Which car do you want to install the engine in? |
Thanks for asking. I was wondering the same thing.
I thought it was an airplane engine. Based on the first post, "Areo!"
_________________
I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!
There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo! |
|
| Back to top |
|
|
Anatolviper
Samba Member
Joined: April 18, 2021
Posts: 19
Location: Rus
|
| Posted: Sun Apr 18, 2021 3:34 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
| Alstrup wrote: |
OK.
Let me ask this way then: Which car do you want to install the engine in? |
)))
I'm going to install it on the PLANE !!
most aircraft conversions use TYPE 1, but I got a Type 4 engine in excellent condition and am going to use it on an airplane that I built myself.
I just need to get the maximum torque at 2800-3000 rpm.
In our country, there is an experience of successful use of VW engines on an aircraft, but they all used a stock engine without any modifications, and received no more than 65 horsepower, because of the propeller installed directly on the crankshaft, it is not possible to get more than 3200-3300 rpm, and on such rpm in the stock configuration, the power is not more than 65 hp, and the maximum power of a 2-liter stock engine is 70 hp at 4100rpm
https://www.youtube.com/watch?v=2QcGkSpfHNI&t=96s (start at 0:50) |
|
| Back to top |
|
|
Alstrup
Samba Member
Joined: July 12, 2007
Posts: 7215
Location: Videbaek Denmark
|
|
| Back to top |
|
|
Wreck
Samba Member
Joined: July 19, 2014
Posts: 1218
Location: Brisbane
|
| Posted: Sun Apr 18, 2021 4:20 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
Do you have room for a belt drive reduction ? there was an Australian company building type 4 aero conversions with a belt drive reduction . but I can't find any information on them and think they may have closed . (VW-engines.com) Try getting in contact with Conti Engines they may have some useful information
https://www.facebook.com/ContiEngines/
It is easier to get the HP with a few more revs as I'm sure you already know.
Big Bore type 4 cylinders jump from 96mm (no machining) to 103mm-105mm a lot of machining .
The same amount is machined out of the heads and case for the 103mm-105mm cylinders . It is a lot of machining and strength removed from the heads and case . Considering you will have the gyroscopic force of a propeller flexing the crank/case this may not be a good thing . The case can be reinforced by making side plates that sandwich the case and also allow for extra head studs fitted , this is what some high power turbo engine builders do .
This is expensive machine work , A 78mm stroker crank with a 96mm bore (2260cc)only requires a little work if any on the inside of the case . A Scat C20 maybe a solution , also advancing the cam timing as well . |
|
| Back to top |
|
|
oprn
Samba Member
Joined: November 13, 2016
Posts: 12730
Location: Western Canada
|
| Posted: Sun Apr 18, 2021 5:13 pm Post subject: Re: Type4 Camshafts for low RPM |
|
|
Reduction drives come with a large weight penalty. Depending on the aircraft in question the heavier type 4 engine could already be at or over the weight limit for getting the weight and balance correct.
Three blade props can let you rev a bit higher but come in turn with decreased efficiency over a two blade one.
I have often wondered if a turbo sized for the 2000 - 3000 rpm range would not yield a better trade off in power to weight ratio than a reduction drive.
_________________
We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age) |
|
| Back to top |
|
|
raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21518
Location: Oklahoma City
|
|
| Back to top |
|
|
Vanapplebomb
Samba Member
Joined: November 03, 2010
Posts: 5411
Location: Holland, MI
|
| Posted: Mon Apr 19, 2021 4:17 am Post subject: Re: Type4 Camshafts for low RPM |
|
|
| Anatolviper wrote: |
| ok, please advise what do I need to replace in a standard type 4 engine to get such characteristics? (High torque at low RPM) |
Not much.
Look up the specs on the 411/914 1.7 and 914 2.0 engine specs. If that is what you want, build your engine that way.
1.7:
-80hp @ 4900 RPM
-98 FtLbs @ 2700 RPM
2.0:
-95 to 100 HP (depending on compression) @ 5000 RPM
-118 FtLbs @ 3500 RPM
The stock 1.7 and 2.0 car engines have exactly the characteristics you are looking for. Bringing any detuned bus engine back to the earlier high compression car engine specs will get you exactly what you want.
In your case because it was a later 2.0 bus engine, ditch the awful 1976-‘83 dished bus pistons and replace them with the 1973-‘76 flat top pistons. This bumps the compression up back up to about what the early 95-100 hp engines had.
The bus 2.0 engines also used the smallest valves of any T4. For a bit more breathing, you can go with the earlier three stud 2.0 heads, or the 1.8 heads which are more durable. 1.8 heads will also get you more compression than the 2.0 heads. Between bringing compression back up from bus spec to car specs, you are right at your goal.
Also, get rid of the factory head gaskets. VW themselves put out a tech bulletin to remove them. Lap the cylinders to the heads. Tighten up your deck height to at least 0.040”, and 0.030” is better if you are confident in your measuring skills.
Ditch the Ljet FI and go carbs. A set of 40mm carbs will work better when set up correctly.
It may sound counter intuitive, but the later bus engines were in such a bad state of tune that you will actually see a reduction in engine temps by raising the compression and tightening the deck. Shoot for 8:1 - 8.5:1 compression, and it will run great with a mild cam. The Web 142 is pretty close to the stock cam, not exact, but close enough. It isn’t the most efficient cam, but going bigger will move the torque peak up higher in the RPM range...not what you are after.
_________________
1800 Type 4 Berrien 295
http://www.thesamba.com/vw/forum/viewtopic.php?t=487021 |
|
| Back to top |
|
|
oprn
Samba Member
Joined: November 13, 2016
Posts: 12730
Location: Western Canada
|
| Posted: Mon Apr 19, 2021 4:55 am Post subject: Re: Type4 Camshafts for low RPM |
|
|
With all due respect Mr. Vanapplebomb, this fellow is on the wrong forum and us car guys do not fully appreciate what is involved for aircraft application. I am not wanting to offend you but here is how it is as far as I understand it.
| Vanapplebomb wrote: |
1.7:
-80hp @ 4900 RPM
-98 FtLbs @ 2700 RPM
2.0:
-95 to 100 HP (depending on compression) @ 5000 RPM
-118 FtLbs @ 3500 RPM |
Any HP above 3100 rpm is irrelevant on a direct drive prop as the prop tips go supersonic and cause all kinds of issues. If he uses a reduction drive then maybe but running a VW engine continually at those rpms is not a formula for long engine life. He would be far better to go 2 stroke in that case for a huge weight savings, the same power and similar engine life.
Remember - aircraft engines run 100% power for the first 5 minutes or more, then back off to 80% or so for cruise. This is not a 10 second drag strip runner!
| Vanapplebomb wrote: |
In your case because it was a later 2.0 bus engine, ditch the awful 1976-‘83 dished bus pistons and replace them with the 1973-‘76 flat top pistons.
Also, get rid of the factory head gaskets. VW themselves put out a tech bulletin to remove them. Lap the cylinders to the heads. Tighten up your deck height to at least 0.040”, and 0.030” is better if you are confident in your measuring skills. |
Yes but do not limit your thinking to stock compression ratios. As a pilot he will have easy access everywhere he goes to 100 octane aviation fuel without road tax. 10/1 or even higher is well within reason!
| Vanapplebomb wrote: |
| Ditch the Ljet FI and go carbs. A set of 40mm carbs will work better when set up correctly. |
Here is where some major misunderstandings lie. First off, from an aerodynamic perspective, a set of dual carbs with air cleaners sticking up out of the cowl of an aircraft would be the equivalent in drag and visibility of mounting two garbage cans on the hood of your car. Most aircraft typically do not run air cleaners but if you took them off then the propwash would promptly empty the float bowls on those carbs in seconds!
Secondly, aircraft NEED a mixture control that is adjustable from the cockpit. How would you accomplish that with automotive carbs?
Now, we HAVE TO HAVE carb heat ducted in. Normally it's done with a duct from one of the exhaust pipes to the inlet of the carb with a cable operated control in the cockpit to turn it off and on as needed. Picture that added to the two garbage cans already sticking up in the wind!
Now how about the float levels at different aircraft attitudes? Suppose he likes to do rolls, spins or inverted flight?
No, dual carbs as we know them is a non starter. The stock FI may not be... with an aftermarket tuneable control module it just might be the ticket.
Anyway, in conclusion, Ray's advice is spot on. To the OP, get yourself over to the sites Ray posted and those boys will know exactly where the bear poops in the buckbrush!
_________________
We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age) |
|
| Back to top |
|
|
FreeBug
Samba Member
Joined: March 12, 2012
Posts: 4278
Location: deepest, darkest Switzerland
|
| Posted: Mon Apr 19, 2021 5:31 am Post subject: Re: Type4 Camshafts for low RPM |
|
|
Zdrasti
| oprn wrote: |
With all due respect Mr. Vanapplebomb, this fellow is on the wrong forum and us car guys do not fully appreciate what is involved for aircraft application. I am not wanting to offend you but here is how it is as far as I understand it.
| Vanapplebomb wrote: |
1.7:
-80hp @ 4900 RPM
-98 FtLbs @ 2700 RPM
2.0:
-95 to 100 HP (depending on compression) @ 5000 RPM
-118 FtLbs @ 3500 RPM |
Any HP above 3100 rpm is irrelevant on a direct drive prop as the prop tips go supersonic and cause all kinds of issues. If he uses a reduction drive then maybe but running a VW engine continually at those rpms is not a formula for long engine life. He would be far better to go 2 stroke in that case for a huge weight savings, the same power and similar engine life.
Remember - aircraft engines run 100% power for the first 5 minutes or more, then back off to 80% or so for cruise. This is not a 10 second drag strip runner! |
Absolutely! X2
I don't know if those cams are designed for this application, or are they car cams? I assume those are advertised duration. You'll want to keep lift low (like 1/4 of valve diameter or smaller), none of those cams realy looked appropriate.
Reliability is of prime importance, and you should be able to hit those numbers. But is the Type 4's power density interesting anymore at that point?
Source info about the present state-of-art, and stick to that.
Just curious:
whar RPM?
what fuel?
what altitude?
boost?
adjustable fuel-air ratio?
cooling setup (cowlings?)?
carb or injection?
what temps?
twin spark?
service intervals?
oiling and fueling?
It's just for curiosity's sake, so if you don't have time, I'll understand. 
I just think VW planes are really cool.  Wondering about a circlip takes a WHOLE new dimension. |
|
| Back to top |
|
|
|
