Porsche Cooling....

[andy198712]

Hello,

I know this can be a touchy subject but i have read a lot on them, and really have my heart set on "that look"

Whats the current options on T1 shrouds? i've got a 11 blade fan and ring on the way.

Also has anyone here modified the shrouds? have seen a couple threads on a few forums to even the cooling.


Anyone running one of these long term?

will be in a full weight 72 beetle, with 2110

All the best

Andy

[Stripped66]

Also has anyone here modified the shrouds? have seen a couple threads on a few forums to even the cooling.

Yes. Purchase a 4-channel digital CHT gauge (MGL Avionics makes an affordable gauge) and determine the temp differences across the 4 cylinders...if the differences are unreasonable (which seems to be the major argument, sans data), play with vane size, shape and placement inside the shroud (trial and error).

[andy198712]

Yeah thats what i was thinking, where did you get your  channel read out from? they seem to be some serious bucks,

i'm waiting on some info from James at Stateside about their T1 shroud. seems kinda hard to find  a shroud in the UK

Cheers!

Andy

[Stripped66]

I drill a small hole above and parallel to the spark-plug boss and sink the thermocouple into the head. You could use sparkplug ring terminals instead.

IMO, the MGL gauge is relatively inexpensive compared to other multi-channel gauges. Don't waste your money on an analog gauge; they all lack the resolution to be useful when trying to tune individual cylinder temps.

[andy198712]

I drill a small hole above and parallel to the spark-plug boss and sink the thermocouple into the head. You could use sparkplug ring terminals instead.

IMO, the MGL gauge is relatively inexpensive compared to other multi-channel gauges. Don't waste your money on an analog gauge; they all lack the resolution to be useful when trying to tune individual cylinder temps.

do you metal epoxy it in yeah? sounds best for long term, i'll look it up for that gauge, totally agree it needs to be digital to see any differences worth knowing.

hows yours going? i read you extensive thread on the samba

[Stripped66]

The thermocouple fits tight and is currently peened in place. I would consider using a thermal-conductive epoxy, like Arctic Silver.

My temp differences across the 4 cylinders are about 5 F at steady cruise, but on the warm side due to my dry sump pulley. I need to make the fan pulley smaller to increase the drive ratio, and retune the vanes again. My car has been off the road over the last year for chassis work, so with the exception of removing the 3/4 cylinder vane I installed, nothing has changed much since that thread.

[andy198712]

The thermocouple fits tight and is currently peened in place. I would consider using a thermal-conductive epoxy, like Arctic Silver.

My temp differences across the 4 cylinders are about 5 F at steady cruise, but on the warm side due to my dry sump pulley. I need to make the fan pulley smaller to increase the drive ratio, and retune the vanes again. My car has been off the road over the last year for chassis work, so with the exception of removing the 3/4 cylinder vane I installed, nothing has changed much since that thread.

is a drysump pulley too small then? i was wondering if a power pulley was small enough for my 11 blade fan...

[Stripped66]

is a drysump pulley too small then? i was wondering if a power pulley was small enough for my 11 blade fan...

Too many factors to say whether or not a dry sump pulley will work, but I'd suggest starting with a power pulley. You will even find that different pulley ratios affect the cylinder temp variation differently, and temp differences will change at different RPM (fan speed) and at different vehicle speeds (pressure underneath the car). I can't tell you what will work on your car, so you'll have to determine where you're starting from and try small changes to control airflow until you're satisfied.

[andy198712]

Thats fair enough, will start with a power pulley and see how it goes, if i find the need for a DS one i can always get it balanced swell (if my dynamic balancing is done in stages)

cheers bud!

[TomJ]

I'm using a Knuf type 1 fan shroud. Used a Fluke infrared temp gun to check the head temps while running on top and under engine (engine pit).. Number 2 was hottest and 25f higher that the other cylinders. 1,3 and 4 were within 10-15f of each other. I put a Dakota gauge on number 2 as this is the hottest running cylinder, obviously due to the oil filler neck on a type 1 motor..

The Dakota gauge is digital unit and the sender is an under the plug type, it's extremely sensitive snd its amazing how much the head temp changes from load to letting off the gas. Sitting in traffic with a berg power pulley does make the head temp creep up but nothing near valve seat falling out temps.

I have bought an MSS shroud (different style with almost a flat back http://kaefer.motor-sport-service.de/html/comp_t1_13.html ) and will try this sometime , I have to cut it up and modify it as my motor is wide..

Cheers

Tom

[andy198712]

Cheers buddy i'll take a look at those shrouds.

Got my fan today which is cool!

quick question, when people mention fan ring sizes, where are they measuring that from? as mine has the cast long groves on it, but at the back has a little lip that kicks out, if that makes sense? which bit do i measure so i know if it needs machining or not?

the part number is 901 106 101 5R

i think thats 1968 11 blade....

[andy198712]

Tom, i dont suppose you know what size fan and size of those shrouds do you? German isn't my forte!   

[TomJ]

Tom, i dont suppose you know what size fan and size of those shrouds do you? German isn't my forte!   

The competition shrouds use a 260mm fan.

Cheers

Tom

[andy198712]

Cheers buddy