Rear mount turbo

deetes · Post by **deetes** » Sat Jul 14, 2012 5:07 pm

Before everyone starts moaning read this: http://www.junkyardturbos.com/Rear-Mount-Turbo.php

I'm just looking into the feasibility of this on a 3.9 TVR. Looking for turbo suggestions and where to source or from which vehicles. The Yanks seem to be using turbos off some their diesel pickups, but we don't have that source. Any help would be appreciated.

stevieturbo · Post by **stevieturbo** » Sat Jul 14, 2012 8:37 pm

There is nothing new about it, check STS turbo.

They are actually very popular and do work well.

Although I suspect the TVR's big up and forward manifolds would be a negative.

What sort of power are you after, what sort of money are you looking to spend ?

A friend has a Precision 6265 ball bearing unit for sale that would work well. Would be good for around 500bhp ( made close to 600 on a 4cyl turbo ) and should spool very early on a 3.9 V8

deetes · Post by **deetes** » Sun Jul 15, 2012 10:06 am

Checked out STS, but I was trying to do this on a pretty tight budget and was looking for Turbos off diesel trucks etc as a means of establishing whether it was worth spending more at a later date. (hope that made sense)

TVR390s just have regular down ward manifolds.

It's putting out around 240bhp just now and I was hoping for 300. That's maybe a bit optomistic, as according to the website, I posted, it would only be 4 psi boost.

Really don't know much about turbo choice at all. The article mentioned a turbine ratio of 0.84 or less.

stevieturbo wrote:There is nothing new about it, check STS turbo.

They are actually very popular and do work well.

Although I suspect the TVR's big up and forward manifolds would be a negative.

What sort of power are you after, what sort of money are you looking to spend ?

A friend has a Precision 6265 ball bearing unit for sale that would work well. Would be good for around 500bhp ( made close to 600 on a 4cyl turbo ) and should spool very early on a 3.9 V8

stevieturbo · Post by **stevieturbo** » Sun Jul 15, 2012 10:16 am

turbos fitted to most diesel engines here will be too small.

You'd really be looking for a 400bhp turbo from a diesel to meet those goals.

A TDO5 turbo fitted to early Subarus is capable of 350 or a little more on that application and can usually be found quite cheaply. So might work ok for your 300bhp goal..
they usually have a 90deg elbow cast into the front housing, it's best to cut this off and turn it into a regular front entry.

You'd still be looking for a 350-400bhp capable petrol turbo off a 4cyl or 5cyl car though for your V8

Maybe some Mitsi Evo stuff, or Volvo 5cyl maybe.

There are lots of cheap Chinese turbos on egay etc. Some people have luck with them others dont. It could be a risk worth taking.

stevieturbo · Post by **stevieturbo** » Sun Jul 15, 2012 10:18 am

an example of a "big 20G" TD05 which would be ideal ( regular is a 16G compressor wheel )

http://www.ebay.co.uk/itm/Subaru-WRX-ST ... 2ebfd3fa80

This is of course a cheap chinese copy though. It may work, it may not. You'd be using it in a less stressed and lower boost environment than a 4cyl car though which would of course help

Jono FD3 · Post by **Jono FD3** » Sun Jul 15, 2012 3:58 pm

the other option is to look at the Holset turbos.... they tend to be used on fairly large commercial Deisels (and fitted to most of the american trucks

) on the bay you can pick them up for reasonable money, but don't go too big or you will be waiting for them to spool and have about 500rpm of big power!

Jono

DaviesDJ · Post by **DaviesDJ** » Sun Jul 15, 2012 8:54 pm

Wouldnt dealing the exhaust joints be a problem all the way to the back?? And what about oil feed??

stevieturbo · Post by **stevieturbo** » Sun Jul 15, 2012 9:24 pm

Your exhaust should be sealed the entire way anyway, so it isnt a major issue, especially on a low boost install.
If you intend pushing harder, get rid of any slip joints and use flanges everywhere.

Oil feed is no different to any turbo install, just a longer pipe.

the oil return requires a pump though.

deetes · Post by **deetes** » Mon Jul 16, 2012 3:17 pm

Couldn't find an application list for uk vehicles with Holset turbos and not sure which one would be suitable. Across the pond they seem to be using HX35s on Mustangs etc, so maybe an HX30 or smaller??????

Jono FD3 wrote:the other option is to look at the Holset turbos.... they tend to be used on fairly large commercial Deisels (and fitted to most of the american trucks ) on the bay you can pick them up for reasonable money, but don't go too big or you will be waiting for them to spool and have about 500rpm of big power!

Jono

Jono FD3 · Post by **Jono FD3** » Tue Jul 17, 2012 10:16 am

you probably wont find any UK vehicles using the Holset turbo as they tend to be for commercial applications with Cat, Cummings etc..... basicaly big Diesels which is what the ford trucks use in the US

cummings and duratec diesles in the pickup trucks!

JJMclure · Post by **JJMclure** » Tue Jul 17, 2012 12:36 pm

What's your intended use for the car? Apologies for the ignorance but what engine size is the car? Have you looked at a turbo off a v6 diesel vauxhall? If I remember right the v6 vectra/signum has a fairly large hairdryer that might be ok in a rear mount application

Eliot · Post by **Eliot** » Tue Jul 17, 2012 10:21 pm

JJMclure wrote:What's your intended use for the car? Apologies for the ignorance but what engine size is the car? Have you looked at a turbo off a v6 diesel vauxhall? If I remember right the v6 vectra/signum has a fairly large hairdryer that might be ok in a rear mount application

Likely to be too small. You need something of a 6-7L diesel engine.

stevieturbo · Post by **stevieturbo** » Tue Jul 17, 2012 10:34 pm

Vauxhall did make a turbo V6 petrol though I think.

But chances of finding a turbo like that cheap are slim.

Maybe something like a GTS Skyline which was a 2.5 single turbo, or old single turbo Supra

Although at £150 for one of the chinese units, I'd probably take a chance.

chodjinn · Post by **chodjinn** » Wed Aug 15, 2012 11:15 am

Holset HX35. Cheap to get hold of, produce good power and more reliable than cheap chinese copies. If I was to ever consider turbo again, I'd get one of those.

deetes · Post by **deetes** » Fri Aug 17, 2012 2:04 pm

chodjinn wrote:Holset HX35. Cheap to get hold of, produce good power and more reliable than cheap chinese copies. If I was to ever consider turbo again, I'd get one of those.

Any suggestions as to where to get one? They all seem to be in the States