[firechicken]

I've been working on a set of manifolds for my TT project for a couple of days now and thought I'd post a couple pics of my progress. The drivers side is tough with the steering stuff in the way but I think this will work. Any input welcomed good or bad.

Drivers side

[455Bird]

Here's my twin turbo effort. Twin TO4b turbos. 462ci. 69Bird. 3.25gear

[mikeb]

Yeah, I wish I had a set of those gathering dust too. As usual PMD engineers were way ahead of their time.

The design of the manifolds does give me some ideas on how to proceed on my own DIY manifolds whenever I save enough pennies to proceed in that direction.

[firechicken]

downpipe

[firechicken]

Passenger side Y upturn

[firechicken]

I considered 301 manifolds as well and the passenger side would work well. The problem on the F-body is where to run the downpipe on the drivers side. 455turbo routed his around the steering shaft and was obviously not an easy task. I'm sure he realizes the problem in this area. My car, however, is a 4-speed and the Z bar prevents this routing. The only ideal route I could see other than modifying the firewall was between the #5 and #7 cylinders by snaking the #7 exhaust tube to make room for it as noted in the above pic. The only other option is a very long pipe that crosses under the frame rail at some point which is unacceptable to me. A 301 manifold or any other for that matter would block this passage way.
I have 2 T-3's from Regal T-types which I'll probably use. I do have 1 turbo from a 301 car and if I can find another I will use them. In fact if anyone on the board has a decent one lying around I may be interested in swapping for Poncho parts or possibly purchasing.

[firechicken]

Drivers side

[TTAJay]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Tom Vaught:
Some years ago a Pontiac Engineer named Skip McCully and I talked about using TWO of the
Pontiac 301 Turbo cast iron manifolds (one for each bank) on a 455 twin turbo deal he
was interested in.
...

If you could find two of the turbo manifolds you might save a lot of work on that plumbing.
...

Tom V. <HR></BLOCKQUOTE>

Though this isn't going to help firechicken with his setup I thought this info might be helpful to other people starting their own twin turbo project. I've got 2 passenger side Turbo 301 exhaust manifolds I'm planning on running for my twin turbo setup. On my '79 TA it looks like it clears the steering shaft. The only things these manifolds need to put on a 325-455 is to have the center exhaust bolt hold plugged/welded and to weld a cap over the bottom exhaust outlet.

One thing to look out for is that 95% of these turbo 301 exhaust manifolds are cracked. If you know a good welder that can weld cast iron then it isn't a problem.

I realize that these manifolds won't flow the same as a nice custom header but I'm just trying to keep it stupid simple. I can always just turn up the boost.

[455Turbo]

How about losing the Z-bar? You could use a hudraulic throwout bearing like this one from Howe Racing. It would take some effort to mount a master cylinder for it but it could free up some space. I took a look at my car and it looks like there's some room for it.

[firechicken]

Twin turbo Pontiac in 1961 Wow! I wish I had a pair of those collecting dust in my shop. Pontiac engineers never cease to amaze me.

[455Bird]

I went about turbocharging my 79TA a little bit differently. I wanted to make some custom headers but it's such a tight fit that I gave up and just used standard exhaust manifolds. The hard part of the single turbo is connecting both sides of the exhaust before entering the turbo. As you'll see, I ran my exhaust around the oil pan. It has worked very well and you can't see any of the piping without crawling under the car.

I think your headers are looking great! Keep up the good work! Oh and 455Turbo made some KILLER reverse manifolds! I was blown away when I saw those.

[Mo]

Forgot yours is a dual draw through system. That is gonna be a wild looking set up when your done.

[Mo]

What diameter pipe are you using? You are better off using 4 smaller pipes or do what 455turbo did with one common tube that all 4 feed into. A turbo exhaust system is complex and takes up alot of room. Your set up should work but may not be as efficient as one with individual runners but it's still better than mine.

[455Turbo]

Nice work. It's good to see another twin turbo Pontiac coming along.

[Tom Vaught]

What size turbos are you hoping to run?

Some years ago a Pontiac Engineer named Skip McCully and I talked about using TWO of the
Pontiac 301 Turbo cast iron manifolds (one for each bank) on a 455 twin turbo deal he
was interested in.

He was going to use two of the 301 turbos on a custom draw thru deal.

I looked at the deal and saw some good things with his ideas.

If you could find two of the turbo manifolds you might save a lot of work on that plumbing.

The other option is to make two manifolds that look like upside down Chebby small block "Rams Horn" pieces. The FACTORY 421 turbo manifolds I had were cast similar to that
style but would not fit an A-Body car, only a B body car. (Possible F body too).
Not sure about the later years but know the 67-69 bird and B car swap.

Tom V.

[goatnut4909]

maybe you could use a set of old headers and cut all the pipe of after the flange then you should be able to run seprate pipes for each port lookin good though

[firechicken]

I've been working on a set of manifolds for my TT project for a couple of days now and thought I'd post a couple pics of my progress. The drivers side is tough with the steering stuff in the way but I think this will work. Any input welcomed good or bad.

Drivers side

[Taff]

How about a pair of these? Looks like Pontiac were ahead of the game.

[Tom Vaught]

You guys like those manifolds?

I had the only set in existance for a couple of years along with all of the other pieces.

Turbos, cross-ram, waste-gates, discharge pipes, etc.

I collected the stuff over many years and eventually sold it to Randy Williams hoping that
we would eventually put a twin turbo big car together.

Tom V.

ps it would not be that hard to duplicate those manifolds with weld-ls.

Tom V.

[455Bird]

Here's how it routes around the oil pan.