So is a turbo the only way to get into the low 11's or 10's???

[navyavi469]

Originally Posted by JayC

Because you need exhaust velocity to spool a turbo. With a rear mount, you have a lot more tubing between the engine and the turbo and the turbo and the intercooler. More tubing means more exhaust needed to fill up the tubes.

The work around is to drop the AR ratio down. This effectively spools the turbo quicker but sacrifices top end power. It also creates more back pressure between the engine and the turbo, which isnt a good thing.

Which is why most rear-mount systems, even for non-stroked engines, are TWIN turbo, which have smaller wheels but comparable A/R to a big single.

In any case, its not that much difference in lag, you'd think it would be, but there's SO MUCH air moving through a turbo system it would blow your mind. The differences are negligable.

Dont forget the fact that the close you can mount the turbo to the exhaust manifold the more efficient it becomes, turbos are heat monsters, get em hot and they start to perform more efficiently.... the exact opposite of a supercharger.

[FLsrt8]

To be honest I purchased the STS kit and after running most of the parts that came with it. Its a piece of junk and had to make several changes to make it a good system.

[JayC]

Originally Posted by FLsrt8

Jay, I can understand what you are saying but for street cars, not so critical.

It might not be as critical but for argument sake, again, you cant make a rear mount spool as good as a front mount comparing apples to apples.

Also, depending on how far down you have to go in AR, you can cause premature turbo failure from overspinning the thing at higher RPMs.

Here's a few videos of some things we've done. We dont work on Cherokees or any Dodge stuff so I dont think there's any harm in posting it. We know turbos

You Tube

http://videos.streetfire.net/video/1...ang_147237.htm

You Tube

[FLsrt8]

You made my point. If I was to build a race car. The turbos would be up front.

[rainmaker]

Originally Posted by navyavi469

Dont forget the fact that the close you can mount the turbo to the exhaust manifold the more efficient it becomes, turbos are heat monsters, get em hot and they start to perform more efficiently.... the exact opposite of a supercharger.

So you're saying someone needs to invent the rear-mounted supercharger then?

[YoungMedic23]

So when will the 454 ban take place???

When I see an 02 Camaro drive by all the people rubber neck and ooooohhhhh aaaahhhhh

this guy is is a JOKE and he's ignorant as hell

[YoungMedic23]

I'm ready to talk about potential 10 sec Jeeps already not turbos and a 10.5 second Jeep in the 1/8th mile

[JayC]

Originally Posted by FLsrt8

You made my point. If I was to build a race car. The turbos would be up front.

How did I make your point? There are a lot of reasons people go with rear mounts and truthfully a lot of it's because it's easier to develop and fabricate, not because its better by any stretch of the imagination.

Building turbo kits with the turbos up front can be quite involved. GENERALLY speaking, you have far less intricate fab work in rear mount systems.

You can defend rear mount stuff all you want but at the end of the day, ITS AN INFERIOR DESIGN. Ive been working with turbos for close to 30 years so I think I have a little experience in the field.

If a rear mount floats your boat then cool but saying its better or even on par with a front mounted system is wrong. Without velocity, you have nothing and there are only so many ways to keep velocity up when you have that long of a tubing run and all of them sacrifice performance.

[FLsrt8]

Jay one of the things we will be testing after its back together is the back pressure. We will be working with Precision turbos and make what ever changes we can. If that does not work out. LPM will move them to the front but not in the engine bay.

[FLsrt8]

Originally Posted by JayC

How did I make your point? There are a lot of reasons people go with rear mounts and truthfully a lot of it's because it's easier to develop and fabricate, not because its better by any stretch of the imagination.

Building turbo kits with the turbos up front can be quite involved. GENERALLY speaking, you have far less intricate fab work in rear mount systems.

You can defend rear mount stuff all you want but at the end of the day, ITS AN INFERIOR DESIGN. Ive been working with turbos for close to 30 years so I think I have a little experience in the field.

If a rear mount floats your boat then cool but saying its better or even on par with a front mounted system is wrong. Without velocity, you have nothing and there are only so many ways to keep velocity up when you have that long of a tubing run and all of them sacrifice performance.

Only because you show us a race car. No other. I agree they are best up front but it has been fun working and driving this rear mount system.