J tubes shields aka industrial tins question

[martyrg]

I'm using an A-1 Lowdown header system. The J tubes run underneath the push rod tubes, about half way between the engine case and the cylinder head. I'm thinking of copying what 1961 bluebug is doing, but I'm concerned that will not be enough area for engine cooling air to expelled from under the engine without restriction. Anybody else think this might be a problem?

[AlteWagen]

I was thinking the same thing. Narrowing the sled and industrial tin to me would cause a restriction in the flow of exiting air.

Has anyone run no tin then installed the sled/industrial and seen differences in temps?

[henrym]

[AlteWagen]

pics please

[martyrg]

Yes yes, pics please!! There was an article in Hot VW a little while back that showed a guy putting the same type of heat shields on his J-tubes. His claim was it reduced the amount of radiated heat that was transferred to the pushrod tubes, thereby lowering his oil temp by about 10*(?) if I remember correctly. I'll look through my "library" and see if I can find the issue and page number.

So there are others out there thinking that the modified sleds and industrial tin might present a cooling problem - Hummmm. I was taught as a general rule of thumb that your cooling air exit area needed to be as free and unrestricted as possible.

[henrym]

Hi...here are the pics. I'll be the first to admit...this is a low-tech method but it works perfectly. The size of the shield is not important--its's having a free air gap between the pipe and the shield. I was a jet mechanic for years and some bleed air ducts use the same technology. There isn't much space between the A-1 lowdown and the pushrod tubes so the clearances are key. I set these up to clamp to the J-tubes so I could remove them with ease. Naturally for show purposes, I'll have them cadium dipped then plated in diamond encrusted gold

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1967 Bug (Second owner)

[martyrg]

So how much of the J-tube does the shield cover?

[hemifalcon]

Here is my way of keeping the heat away from the pushrod tubes/heads.. Again, thanks goes to HenryM for seeing his version last year.. I haven't drilled the holes yet for the 6mm screws/bolts in the sump.. Maybe tomorrow..
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'62 VW Bug Sedan (Ruby Red)
Resto pics> http://smg.photobucket.com/albums/v697/hemifalcon/Bug%20resto/?start=all&paginator=top

[bartman]

You can also install studs in the bosses on the underside of the head to help mount it.

This is what I did with mine:

This shows how far you could go before interfering with the thermostat:

[ALB]

Well done, Bartman!
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On a lifelong mission to prove (much to my wife's dismay) that Immaturity is Forever!!

[67 Sunroof]

Old thread but good reading here! So I’m nearing completion on a 1776 build with a-1 header and j tubes.
I guess there are 2 types of header from a-1. Looked at mine tonight and the j tube is soo close to the block that I cannot mount my thermostat!? Any thoughts on this? I want to run the stock tins and also run my thermostat.
I did buy industrial tins but something isn’t jiving!?
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1776cc, CB crank, CB 2241 cam, CB light lifters, CB H-beam rods, CB light flywheel, Mahle forged pistons, A1 Sidewinder exhaust, Dellorto drla 40’s, Hoover modded case, fully balanced, fully flowed, heads by www.type-emotorsports.com, Air ride suspension by https://www.airkewld.com/?Click=3989

[Glenn]

As far as I know, the Berg headers do clear. I have the GB-933S

Last year I built a 2017 for a customer that had a A1 Sidewinder and Dansk large tube heater boxes. I got it directly from Tiger.
#Swht112 stainless sidewinder header

It fits all stock tins and the thermostat, so J tubes and industrial tins would also work.
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Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"

Member #1009

#BlueSquare

עַם יִשְׂרָאֵל חַי

[67 Sunroof]

I dunno Glenn. I see some gaps down under there! I want it closed off all the way to the heads to keep the heat away from them.
I cannot mount the bracket at all? No I don’t have type 3 tins either. I bought the cool tins but decided against them after 23 pages of reading😂😂
Here is the picture I posted in another thread. The j tubes are just too close to the bracket.?

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1776cc, CB crank, CB 2241 cam, CB light lifters, CB H-beam rods, CB light flywheel, Mahle forged pistons, A1 Sidewinder exhaust, Dellorto drla 40’s, Hoover modded case, fully balanced, fully flowed, heads by www.type-emotorsports.com, Air ride suspension by https://www.airkewld.com/?Click=3989

[Glenn]

Your J tubes are designed for a "narrow" header. That's why the bracket doesn't fit.

_________________
Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"

Member #1009

#BlueSquare

עַם יִשְׂרָאֵל חַי

[evanfrucht]

[67 Sunroof]

You’ve managed to clear the air for me. I just figured it would all fit. NOT
Yeah I have the slip fit j tubes.
Come to think of it I actually have TWO A-1 exhaust systems. (Yeah I buy everything in 2’s. Hahaha
I’ll look at the other one which is ceramicoated and see if they are the same “slip fit” design. Probably is though.
Yeah, would you mind posting a few pics when you get a chance?
Thanks for your help guys! So much for assuming it would all fit. Looks like I’ll be modifying the bracket. I’m not coming this far and then not use the thermostat.
Glenn your builds are top notch. Always clean and just done RIGHT. I commend your passion for perfection.
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1776cc, CB crank, CB 2241 cam, CB light lifters, CB H-beam rods, CB light flywheel, Mahle forged pistons, A1 Sidewinder exhaust, Dellorto drla 40’s, Hoover modded case, fully balanced, fully flowed, heads by www.type-emotorsports.com, Air ride suspension by https://www.airkewld.com/?Click=3989

[evanfrucht]

Before (basically touching, no room for sled tins)

After ( )

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1967 Bug ( the daily rod )
1964 Fury Wagon ( the pavement shredder )

[mondshine]

This guy's videos are fun to watch.


Link

[cmaxcliff]

Does anybody use heat tubing to cover the pushrod tubes?

[Glenn]