My draw through turbo

With Turbo and Super charging you can create massive horsepower with vw motors.

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sideshow
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Re: My draw through turbo

Post by sideshow » Sun Dec 10, 2017 10:47 am

Probably power brake vacuum source.
Yeah some may call it overkill, but you can't have too much overkill.

advinnie
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Re: My draw through turbo

Post by advinnie » Sun Dec 10, 2017 12:13 pm

Cheers mate I’ve still not found out what the hole is for but I will continue looking 😁

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buguy
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Re: My draw through turbo

Post by buguy » Sun Dec 10, 2017 12:36 pm

Have you taken the plug out to see if it's just open to the manifold? If it is then it's simply a vacuum source.

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Chip Birks
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Re: My draw through turbo

Post by Chip Birks » Sun Dec 10, 2017 2:30 pm

Definietly not preheat there. Thats usually under the manifold. Looks like a hole for a temp sensor, or water injection or something.

advinnie
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Re: My draw through turbo

Post by advinnie » Sun Dec 10, 2017 4:37 pm

Took the plug/bolt out and it’s just a straight hole that goes into the manifold air stream

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Re: My draw through turbo

Post by advinnie » Mon Jan 15, 2018 9:59 am

Here’s a link to the latest video of my 1600 draw through turbo bug now I’ve replaced the broken piston and cylinder and now with a slightly different exhaust
https://m.youtube.com/watch?feature=you ... 9qoJm3nsvA

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buguy
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Re: My draw through turbo

Post by buguy » Mon Jan 15, 2018 10:49 am

Sounds tough!
She loading up a little at idle? Do you know your AFR?

advinnie
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Re: My draw through turbo

Post by advinnie » Mon Jan 15, 2018 1:37 pm

She was loading up but I’ve sorted that out now. I had a bad needle valve and it was not shutting of the fuel that well and was slowly flooding the engine when at idle so changed it and all’s good. Yes I have a lm-2 hand held reader but it’s just reading 100% rich at idle (8.5:1)

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buguy
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Re: My draw through turbo

Post by buguy » Mon Jan 15, 2018 2:57 pm

Well I love the way a draw through sounds so I'm biased. I love that crackle! I have been working on that with my 4 barrel. I'm not sure if it's better to have it a bit leaner at idle to save from carbon monoxide poisoning and in case of a traffic jam and have to fatten up quicker as it builds boost, or to just run it around 12.5 or so and less risk of a lean spike. I guess it's all about experimentation.

advinnie
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Re: My draw through turbo

Post by advinnie » Mon Jan 15, 2018 4:48 pm

I’m planning on running it slightly rich to play it safe for the moment. I’m seeing 14.1:1 on a cruise and at WOT no boost I’m getting a reading of 13.0:1 and WOT @ 8 psi I was seeing 12.4:1 but as soon as she starts to idle I get a reading of 8:1

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buguy
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Re: My draw through turbo

Post by buguy » Mon Jan 15, 2018 7:39 pm

Sounds like you have it running pretty well besides the idle. I wish I could help but I have never touched one of those carbs.

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WickedWagens
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Re: My draw through turbo

Post by WickedWagens » Sat Jan 20, 2018 12:39 am

That exhaust sounds great!
1968 Ghia Land Speed Car
G/CFALT 106.643 MPH 8/2016
G/CGALT 113.131 MPH 9/2016
G/CBGALT 134.606 MPH 8/2017
G/CBFALT 146.715 MPH 8/2017
G/CBGC 158.242 MPH 9/2017

advinnie
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Re: My draw through turbo

Post by advinnie » Sat Jan 20, 2018 3:30 am

Cheers mate.
I do have one small problem I need to sort out and that’s it now. The carb icing has now been sort, I sorted that but getting a 2” diameter hose and rammed it up underneath the cylinders to catch all that lovely hot air and routed the other up underneath the carb manifold and it’s worked a treat. Anyway the last issue I have to over come is if I accelerate normally all is good the engine picks up speed and nicely comes onto boost but if I floor it in any gear she will stumble and popping can be heard from the exhaust.

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buguy
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Re: My draw through turbo

Post by buguy » Sat Jan 20, 2018 8:42 am

I seem to get that with mine if I have a vacuum leak somewhere. Have you check that out yet?

advinnie
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Re: My draw through turbo

Post by advinnie » Sat Jan 20, 2018 9:10 am

I will go recheck now for a vacuum leak

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