Type 4 buggy motor

[Blitzkrieg]

The scrapyard is not accessible to me at the moment.Maybe in the New Year

[Bugger]

first need to get the bus home and then can go there and see what are needed thanks again

[AirPower]

Guys - on my path to enlightenment - please help me with this: Rod Ratio's

When you use a stroked crankshaft, you use longer conrods (am I right?) otherwise the rod ratio drops too low and you end up with a tractor motor.

If you do this you need to do something about the deck-height (the piston is going to be shoved out the top of the cylinder). Now what is the best way to clear this problem - use extended barrel (cylinder) lenghts or use pistons with a reduced compression height (pin to top of piston).

Maybe a combination of both? As I see it the best is to use the reduced compression height pistons - then you don't need to change the pushrods and tubes. For a 78mm stroker and 144.8mm conrods the added stroke is 20.8mm - do you get piston where the compression height is reduced by so much?

I am finding it hard to get information- what is the standard compression height of 94mm type 4 pistons and where can I look for options?

[Tony Z]

Stroke is defined as the length that the piston moves. The conrod has no effect on this.

Going from a 71mm stroke to a 78mm stroke adds 7mm to stroke. Thats 3.5mm at the top and 3.5mm at the bottom. So you need to either have pistons that have a 3.5mm lower compression height (highly unlikely), pistons that have had the gudgeon pins moved up closer to the rings or a con-rod that is 3,5mm shorter.

On my engine build (suicyde engine in projects section) I posted a picture of where the piston stuck out of the sleeve, then I got a pic of a spacer which I inserted betw the case and the cylinder and then you can see the new deckheight of 1mm.

On a T1 if you buy a 82mm stroker crank and use stock length rods, you can buy a set of stroker pistons which have the gudgeon pins raised closer to the rings and you end up with the piston in the stock position...

[AirPower]

O.K - my wording is a bit wrong there - the stroke won't be 20.8mm more, and my calculation is for 7mm added stroke but I'm sure the piston will still move 17.3mm further out of the cylinder (my info says standard conrod length on the 2.0L TYPE 4 is 131mm) What I mean is at TDC, piston will be extend by - (added stroke + added conrod lenght) from normal.

If the added stroke is 3.5mm plus the added conrod length of 13.8mm - I would need to deal with 17.3mm. So I need to find pistons where the pin is moved up by that much?

[Tony Z]

piston will move up the added conrod length plus half the added stroke.

You'll prob end up with stroker pistons and then have to shim out or cut the barrels accordingly

[Tony Z]

look into these topics and read them through. They should answer most of your questions

http://www.aircooledvwsa.co.za/viewtopic.php?t=74

http://www.aircooledvwsa.co.za/viewtopic.php?t=75

http://www.aircooledvwsa.co.za/viewtopic.php?t=72

http://www.aircooledvwsa.co.za/viewtopic.php?t=58

[AirPower]

Been reading a lot of posts about this motor (thanks Tony for pointing me in the right direction)

Here are some more links that I found very informative:

http://www.shoptalkforums.com/viewtopic.php?t=108620

http://www.shoptalkforums.com/viewtopic.php?t=106178

scott the viking seems like a very cool dude - all credit to him for sharing his knowledge.

http://www.wallaceracing.com/techarticles.htm

http://www.dune-buggy.com/

I can now add the type 4 manifolds to the list of parts.



Bugger if you see this post - remind me again who I should talk to, to get type 4 parts imported? Please and thanks.

Over and out for now.

[Bugger]

Go to this site for stroker canks


http://www.aircooledtechnology.com/stor ... hp?cat=269

[flatfourfan]

pm sent.

Can I ask you guys - do you get such a thing as a camshaft that is suitable for turbo use as well as non-turbo use. I see on the net people are talking about a 86a, but the cam suited for a turbo application is totally different. Is there a middle way?

[AirPower]

Thanks Bugger - I had a look there - 78mm cranks are converted to use type 1 big-ends. Seems that's the only way to go.

Let me take this opportunity to say I am HIGHLY disgusted with the service from the so-called SCAT parts suppliers that I contacted in Gauteng area. Not one of them even got back to me about SCAT parts that I asked for, even after I supplied them with the part numbers from the SCAT catalog. Most didn't even know what I was talking about when asked about type 4 performance parts. sies man! Best of all is they advertise that you must contact them for ALL your SCAT performance needs. Sorry guv' I won't contact you again even if you PAID me.

I see what Tony meant about the problem to get parts in SA. So I'm setting up accounts to import and can only hope things go as planned. Toughies for SA businesses.

Mario.

[flatfourfan]

I take my money overseas..........just a pity with the recent drop in the rand though.

[Blitzkrieg]

Thanks Bugger - I had a look there - 78mm cranks are converted to use type 1 big-ends. Seems that's the only way to go.

Let me take this opportunity to say I am HIGHLY disgusted with the service from the so-called SCAT parts suppliers that I contacted in Gauteng area. Not one of them even got back to me about SCAT parts that I asked for, even after I supplied them with the part numbers from the SCAT catalog. Most didn't even know what I was talking about when asked about type 4 performance parts. sies man! Best of all is they advertise that you must contact them for ALL your SCAT performance needs. Sorry guv' I won't contact you again even if you PAID me.

I see what Tony meant about the problem to get parts in SA. So I'm setting up accounts to import and can only hope things go as planned. Toughies for SA businesses.

Mario.

Try Thundersport in Pinetown, they import parts from the US and I asked them if they can get SCAT Parts. The answer was yes, just phone them and speak to Mike Egan. very friendly and helpful chap...

Cheers

[AirPower]

OK I'll give them a call - the last try. I'm just waiting for my pay-pal account to be activated then I'm going to order overseas. But thanks for the info.

Mario

[dubster]

hey i have a 1 or 2 of those manifolds...i almost threw them away for scrap alu. cause i didnt know what they were used for...thought they were some kind of adapter for a carb....