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Thinking of Rear/mid mount turbos.

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Old 03-12-2011 | 04:14 PM
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Default Thinking of Rear/mid mount turbos.

Some background and info:

http://www.junkyardturbos.com/

1) Pipes to the turbo, past the exhaust housing, and out the back.

2) Pipes from an intake at the turbo, but in clean area, and then up to the intake.

3) Oil lines to the turbo, restrictor, and a pump to return the oil from the turbo to the engine oil pan

4) Blow off valve by intake

6) Wastegate

7) Some way to run engine in boost (https://rennlist.com/forums/928-foru...wesome-11.html or use MSIII (Megasquirt)

Seems sort of simple. In my case, I would run ethanol, so I would forgo the complexities of an inter cooler. No, its not perfect - Perfect is what I am doing on my 78, and that takes a long time. in 2013, that car will be in its 10th year of production.
Old 03-12-2011 | 05:32 PM
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Go for it, rear turbo's are the bomb in my book!

There is a gentleman on the boards, or two now and lag is a urban myth! They run strong and hard. Plus they sound really cool!
Old 03-12-2011 | 06:27 PM
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Originally Posted by Iwanna928
Go for it, rear turbo's are the bomb in my book!
Thanks for the link lots of cool info!

Originally Posted by Iwanna928
There is a gentleman on the boards, or two now and lag is a urban myth! They run strong and hard. Plus they sound really cool!
I thought rear turbo's were an urban myth!
Old 03-12-2011 | 07:32 PM
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Doesn't that cause problems if you live in CA, unless it's going to be a track car?
Old 03-12-2011 | 07:35 PM
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One of Sean and Rog100's friends just did a rear-mount- it was easy , and he really likes it. I can't remember his name.....
Old 03-12-2011 | 08:22 PM
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I of course, believe that rear mount turbos are just wrong !

The exhaust side of a turbocharger is driven by heat difference across the turbine, by situating the turbo at the rear a lot of that heat (energy) is lost. This is why the exhaust manifold on turbo installations should be as short as possible and lagged or coated to retain energy. Witness the attention to detail on John Kuhns' hot side, indeed his whole installation.

Why not put in a little more effort and build a proper single or twin installation.

My 0.02 cents.

Cheers Roy
Old 03-12-2011 | 08:24 PM
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I did a mid-mount turbo and am a huge fan of it if you have a 5-speed.

Unfortunately, if you have a Rogerbox you will have to do a rear mount.

After doing the mid mount, I am a huge fan of turbo-ing our cars.
Old 03-12-2011 | 08:25 PM
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Originally Posted by Roy928tt
I of course, believe that rear mount turbos are just wrong !

The exhaust side of a turbocharger is driven by heat difference across the turbine, by situating the turbo at the rear a lot of that heat (energy) is lost. This is why the exhaust manifold on turbo installations should be as short as possible and lagged or coated to retain energy. Witness the attention to detail on John Kuhns' hot side, indeed his whole installation.

Why not put in a little more effort and build a proper single or twin installation.

My 0.02 cents.

Cheers Roy
My bolding of your post needs attention to it. Because that is your opinion.
Old 03-12-2011 | 08:36 PM
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Originally Posted by Sterling
noob

wait till you hit 14-15 years of "production"
You are driving your car my old friend. That means you won years ago.
Old 03-12-2011 | 08:36 PM
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Originally Posted by DonT
Doesn't that cause problems if you live in CA, unless it's going to be a track car?
TECHNICALLY, if the car has a cat and the turbo is after that (no, it won't be that way) it would/should/could be legal.
Old 03-12-2011 | 08:39 PM
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Originally Posted by Roy928tt
I of course, believe that rear mount turbos are just wrong !

The exhaust side of a turbocharger is driven by heat difference across the turbine, by situating the turbo at the rear a lot of that heat (energy) is lost. This is why the exhaust manifold on turbo installations should be as short as possible and lagged or coated to retain energy. Witness the attention to detail on John Kuhns' hot side, indeed his whole installation.

Why not put in a little more effort and build a proper single or twin installation.

My 0.02 cents.

Cheers Roy
Absolutely. No Argument. I would just write Todd a check for $xx,xxx and he would do a great job with the project and copy whatever he is doing on a car I give him. But for $xxxx (or even $XXX), I can't do as you suggest. RM and MM turbos work, but obviously not as well as exhaust mount.

Last edited by BC; 03-12-2011 at 09:00 PM.
Old 03-12-2011 | 08:56 PM
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Roy, the fact that the rear/mid mount turbo's WORK is a matter of record here. No argument that closer mounting is better- but its not wrong. It does work, and its a much easier solution for low-boost, bolt-on fun than the twin-turbo setups available.
Old 03-12-2011 | 09:01 PM
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Originally Posted by BC
TECHNICALLY, if the car has a cat and the turbo is after that (no, it won't be that way) it would/should/could be legal.
No to cat, after cat turbo, or no to both?
Old 03-12-2011 | 09:05 PM
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Well, I will not be putting the turbo after the cat. I don't think it should be that way. For testing I may have to finagle something. So no to CAT.
Old 03-12-2011 | 09:15 PM
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Originally Posted by BC
Well, I will not be putting the turbo after the cat. I don't think it should be that way. For testing I may have to finagle something. So no to CAT.
Thanks. Cool project.



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