ShopTalk Forums | Aircooled VW Tech & Restoration Help

Jake and anyone that has this information,

I have one of Joe's DTMs and I realized that I didn't use the type 1 under cylinder tin as I have read about in the past.

Is this tin really necessary? can I just run the engine for now without any tin under the cylinders?


Ephry

My guess is a big fat NO,,,, the tins are designed as a deflector for air flow over and around the cylinders.

Some sort of tin is a necseeity to build upper plenum pressure above the cylinders and force more air through the heads..
The stock TIV tins are too restrictive and should noty be used with the DTM. In our testing they proved to drag down HP and not cool nearly as well or as even as the TI tins.

With no tins in place the air will simply blow to the path of lesser resistance, between the cylinders and not take any heat with it.

Ok, point taken. I'm going to have tofabricate soem to fit under there, or modify the type 4 ones to look mor elike the type 1a?

f i remember your ritings, the tin should be placed closer to the head, and not the block?




Ephry

Can you score some stock TI tins??

maybe. Will have to visit my favorite u-pull-it. The stock 1600 was traded a while ago for an interior


Ephry

MASSIVE TYPE IV wrote:The stock TIV tins are too restrictive and should noty be used with the DTM. In our testing they proved to drag down HP and not cool nearly as well or as even as the TI tins.

With no tins in place the air will simply blow to the path of lesser resistance, between the cylinders and not take any heat with it.

did you try knocking out the spot welded tabs? I remember knocking mine out and my head temps never went over 350 even when driving it hard. Average temps were 290-310 with my 1971cc.

Kevin

Never tried it, the TI tins are so easy to install and they work very well.


I have 200HP 2563 engines that barely break 300 degrees with them...

I have been placing "new" Type 1 tins on Ebay and I also have many used ones available if you are interested. email me....

Billyisgr8 wrote: did you try knocking out the spot welded tabs? I remember knocking mine out and my head temps never went over 350 even when driving it hard. Average temps were 290-310 with my 1971cc.

Kevin

Funny you should mention that. I modified the type 4 undercylinder tin, cause the type 1 tin I could not mount to the head studs (because of the enclosed 964 cylinders):
I'll try to post a pic of them tonight.
Walter[/img]

Jake you say that you should use tins with DTM, what if you are using TIV stock tins. Are the stock bottom tins alright to use? Thanks Rich

Jake,

Could you rate these three tins as to their ability to help cool a Type 4:

Type I tins
Type 3 (also called cool tins in the VW mags)
Type 4 tins

Thanks Jake!

Don

Here is the rating for an UPRIGHT Type IV.

Type I tins *****
Type III tins - Won't fit worth a damn

Type IV tins**

You have to have some tin there, else you lose alot of pressure and no cooling system works without pressure!

MASSIVE TYPE IV wrote:-------------
You have to have some tin there, else you lose alot of pressure and
no cooling system works without pressure!

Yes, without tins, all you have is velocity!

A decrease in velocity will have a proportionate INCREASE in pressure....


Learnt DAT in turbine skool!


Don

Thanks for the clarification Jake. That helps tremendously. Now I can tackle the DTM and make it run at it's optimun. The surrounding tin is in place.



Ephry