Turbo header discussion.

[Mars]

I am going over a few options for turbo header design on my 3500 camaro.

Turbo is a GT4088 going on a cammed 3500V6.

Right now, hotside, I have a "3500 front" manifold on the drivers side and a 3400 front (log) manifold on the pass. side of the car. 2" crossover pipe to the turbo. I went with this due to ease of install and reliability of cast manifolds.

I want to re-do the hotside,

Here are my options :

1. Upgrade the pass side of the system to use another freer flowing 3500 front manifold. (would match the other side and have MUCH better flow than a log) Good reliability and should never leak nice and sturdy.

2. Make equal lenght headers for both sides.

3. Make shorty headers for both sides.

What I'm basically asking is : do the 3500 front manifolds flow enough as not to choke out my setup ??

And my other question is are equal lenght headers as good or that much better than shorties. (The shorties have a shorter path to the turbine, BUT at the cost of not being equal lenght.)

looks like MOST V6 - V8 turbo setups go for a shorty header and drop the whole equal lenght thing... (like they don't ever try to get them close... one primary is usually 3X longer that another one) Kinda like this, most dragsters are done this way I've noticed... :



Pictured here is the 3500 front mani just for reference...



you can see it does have a somewhat good flowing design... I just wonder if it would be THAT much better to upgrade to a 3-1 custom shorty header.... The cast. manifold will hold the heat in alot better than 14 gauge tubing as well...

discuss.

[Joseph Upson]

You can almost stand up and walk through those 3500 manifolds. They are definately a better design than the logs and are contoured for good flow which is one of the first things I noticed upon removing them from the 3500 I have. Headers are great especially for an all out build but except where there's a lot of room to work I don't think I'd ever go that route again given how well the later style manifolds are made. I used 14 GA steel tubing for the headers I made for the 3900 and they worked well but didn't like being wrapped and showed severe flaking after being heated up a few times and allowed to sit for a few months. That's where the durability issue comes in. I'm in FL so a place that has snow and salt mix during the winter might really go to work on them. I considered stainless but I wanted something thicker than 16 GA then I didn't care to spend that kind of cash given their priority relative to other essential parts.

The 3900 wrap around manifold system is an excellent design with all of the ports directed toward the exhaust outlet. I believe they'll (3500 mani) work very well for you. From what I've read over the years in terms of turbo exhaust systems, less is more between the turbo and the engine, the better the contours of the stock manifolds, the less significant the gain from headers.

[Mars]

Why do I get ambitious when I have a wicked hangover ? HAHA

[1988GTU]

You did test fit while making those I hope. ?

I like the looks of those, too bad fwd is so cramped.

[Mars]

You did test fit while making those I hope. ?

Nope...

But, I had the other stupe right beside me, bolted to another spare head and I'm pretty sure it'll clear...

[timg]

Those look great. I hope they fit. I'm looking forward to seeing what comes next.

Tim