TurboCharger Question, Can I do this??? *pic* and help needed!


New Member
Mar 8, 2003
Park Ridge NJ

Im almost complete in finding all the parts for my Twin Turbo convertion

The only thing im missing is the second Turbo,

Now today I had a brain storm,

Why not just single turbo it and the single Turbo could substitute a supercharger?

The way this idea came to me is this,
I DONT want huge power,
I DONT want the fastest car,
I just want a nice little increase in power but not too nuts,

Now looking at the Buick Grand National Engine, Its a Single Turbo, with Efi.
and only ONE header is modified to accomaodate the turbo,

The other header dosent even hook up to the passenger side one at all in anyway!

So on this basis (as in it works for that it should work for me) I can Modify ONE of my headers to accomodate a T3 Hybrid Turbo,
Leave the other header COMPLETLY alone,

and have a low boost single turbo setup,
Surley our little 302's produce enough exhaust pressure to spool a turbo up without haveing to be hooked together
If the grand national engine does is so can mine right?
and the GN only uses a T3,

Obviously I know I have to change injectors, Fuel pump and etc to accomodate the increase in air,

But given this imformation is "Should" work right?
Pic of turbo
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I believe that size/make of turbo is frequently used on 4 cylinder engines in the 2L range - less than half the displacement of the 302. I think even in a twin set up it would be about as small as you'd want to go. Starscream - walk us through your research/background on how you've sized your turbos, what kind of boost you expect, a/r ratio calculations, etc. Also, what were your intercooling plans? Physical size, location, temp./pressure drops across the cooler etc. The single is MUCH easier from a plumbing/fabrication perspective. Why not sell your single T3/4 and replace it with an appropriately sized single?
The Main reason is due to keepinf the exhaust as is,

It looks like I have to have a crossover pipe after all to run this turbo even on a single setup, And its too small :(

So I intend to now complete my twin Turbo setup,
The 2 Turbos are Hybrid T3's,
The intercooler is custom front mount,

From what ive read the temp output would be around 271 degrees before intercooler, and around 181 after,

These cant be taken as gospel ad s ill only know after the convertion has taken place,

Im looking for 6 psi each turbo, The maximum would be 8 or 9 psi,
These turbos could handle that with ease,

Yes they come off 4 cylinder cars, in the 2L region,
But I dont see them being a problem,
I want low power anyway, I dont want to crack the block and I want to be able to use the car.
With everyone else the single would be maxed on it's effiecent range from about 1800 rpm up. Dual t3/4 setups have worked in the past and work good. That would be a good "street" turbo set up that can be alot of fun. Just dont go mod happy without a second daily driver back up car...and a R302 or 351 in your garage.
How are single's better for accelartion. The only way that plays into is lag. If you get a properly matched TT setup you SHOULDNT have any lag if driven correctly right? Again I'm not an expect just going off my theory's on this one. Please dont flame...to much
I read on turbomustangs.com that a twin turbo setup is better for acceleration and spools up quicker,

I really dont want to go mad with this, Hence the low boost,
I want roughly what you get when you stick a Vortech on a stang,
But with that beautiful turbo whoosh!

I miss it!!!
Oh bloody whatever,

Seems the link isnt to the page I wanted you to read,
So i cut and pasted it here

this was taken from Turbomustangs.com, in the FAQ section

Turbo Lag??

I have seen a lot of questions regarding this issue lately. Turbo Lag is the time it takes from the time you smash the "go" pedal to the time the turbos are making an appreciable amount of boost. For some reason people have it stuck in their mind that it takes 10 minutes for the turbos to respond. That is simply not the case. Most of the single turbo kits are making FULL BOOST before 3000 rpm or less (try that with a centrifugal supercharger). Sure, if you mate up a T76 with a large AR number to a stock 5.0 then yes, there will be more turbo lag. But when you get a turbo that is designed to work with your combination then there should be very, very little lag. Twin turbos have even less lag, the power is there right after you hit the gas basically.
You can even launch off the line under boost with a 5 speed if you get a two step.
Update 8-1-02 The Cartech single turbo T64e with .68 exhaust housing on my Heads, cam, intake 306 made full boost by 3200rpm.

(8-1-02) What are the main differences between a Single and Twin Turbo setup?

First off, you can make as much or as little horsepower as you want with either a single or a twin. The main differences between the two are the turbo sizes and the complexity of the entire package. With a single turbo you only have to deal with one of everything, one turbo, one wastegate, one downpipe, and one set of plumbing. With a twin turbo of course you have two of everything so that makes it a little more complex. With a typical street twin setup you use fairly small turbos therefore there is very little turbo lag. Now that Incon is pretty much out of business there is no place to get a highly engineered twin turbo kit for fox body Mustangs. However there are a few places that are coming out with cheap do it yourself TT kits based on junkyard designs that people have been using for years. If you are interested please check them out, so far the feedback for them has been very positive.
Personally, I prefer the single turbo setups because I think they are a little easier to work on because everything on the non-turbo side is just like a stock mustang. So plug access and everything else is unaffected on that side. Also it is pretty easy to swap out a single T60 turbo for a T72. Just loosen a few bolts and bolt on the new turbo and you now have a turbo that can support 850 hp.
Yeah the cars crazy already I guess,

All ive ever had is Turbo Cars
I love the noise, I love the rush of boost,

Im looking for about 400 BHP MAX!!! I really dont want over that, 350 will do fine,

I cant afford a Supercharger, The cheapest 2nd hand one ive seen is $1300,

So for less than half I can twin turbo,
um on a grand national, and every single V engine turbo setup, BOTH sides of the engine go into the turbo. on the GN, the drivers side pipe wraps around the back of the engine and comes back forward on the passenger side and combines with the passenger side exhaust before going into the turbo. you just didnt look at it enough. just one side of the engine would create a very uneven exhaust flow and backpressure and would surely snap the crank or severly damage it over a little time. one t3 is good for up to about 2.5 liters, so you'd need a much bigger single turbo, or just get another one
I know,
I only realised that after I posted the thread,

I just saw a set of GN headers (and I thought they had true duals) and one header was turbo, one was for the start of a h-pipe,

But found out they do have the crossoverpipe
But another Q about the GN,

It uses a T3 right???

How the HELL does it do what it does?
I noticed the power isnt heart stopping either! around 230 BHp right?

Is it really light or something??
Or does it run a huge amount of boost