Headers

[Anonymous]

Bowtiekid and I are going with the V6 Header kit from Headers by ED, but I am running inot problems with the design. We have a lot less room than the 3400 because we have the massive cam towers. And our downpipe cutout I think I can fit 2 X 2 1/4" pipes through. We are trying to keep the primaries equal lengh; and I would like, but it probably won't happen, to keep the 2 collector pipes, both 2 1/4", equal lengh until they collect. Remeber we also have the alternator down there so I can't use that room for turns to keep them the same lengh. As soon as I get the design CADed out we can order the set and begine welding and cutting. The set is $400, which isn't cheap. But Bowtiekid is really comfident in their products and its quality, so I trust him.

36" is really long, but a DOHC and a pushrod, even if they have the same power, are very different as far as their needs go. I am going to call Hooker Headers and email Headersbyed to see how long they think the primaries should be.

More pics of your 3400 would be greatly appreciated!

[RacerX11]

I paid almost $400 for my kit of parts from Ed, and I don't regret it. I wouldn't hesitate to recommend his products. Ed is also very willing to talk to you over the phone about technical details like this, but be careful, he can talk your ear off.

I don't know if this has been posted yet, but here is a guy who made some custom headers for a 3.4 DOHC Fiero. There is also some interesting info on intake design: http://fiero.cc/fiero-tdc/members/mws/ He has some good pics of how his headers ended up.

Here are a couple more pics of my 3400 headers.

Marty

[RacerX11]

Side View:

[RacerX11]

Rear View:

[RacerX11]

Top View:

[RacerX11]

Here are the downpipes shown in the tunnel. The pipe for the front bank of cylinders ends up being about 2 feet longer than the rear. Again, not 100% optimal, but it fits. The setup used to run these 2-1/4" downpipes back another 3 feet to a Y-pipe, then a single 2-1/2" back to a single muffler. This setup was extremely loud (I tried 6 muffler designs, none were very quiet). My new exhast will have two 2-1/4" glasspacks located where the cat normally goes, then back to a Y-pipe into a single 3" pipe back to a single 3" muffler. I am trying to take off some of the edge of the sound created by the headers.

Marty

[Anonymous]

You are a freaking genious!!!

I really like your design. The front ones off your's will work perfect for the 3.4 TDC, but the rears will not. Do you have original designs on paper or ACAD? Because I would really liek to see the measurements and such. I do not want any difference in sound, but it looks as if I have no choice. The kit from Ed is $404. But when Michael and I order together, we will spend $800+, so we will then get 25% off any other random piping we need. I already have a 2.5" mandrel bent catback, so I will use that even though I would like bigger. I would like your design measurements that way I don't have to do it, becuas eit will take me some time to make them true equal lengh.

How much hp/tq did you gain?

a 3.4 TDC with a bad design, not equal lengh, gianed over 1/2 second in the 1.4mi with the headers alone.

[Anonymous]

Looking at your last pic, we have more room for the downpipe it appears, our cutout goes higher in the firewall. I would love to have the motor out, but I spimply do not have the time or determination to do it AGAIN.

[RacerX11]

I don't really have any designs or CAD. I pretty much built the headers on the engine, in the car. These pics were taken when I pulled the engine out for a rework. I had a general idea of how I wanted to route the tubes (my design is pretty much a knock-off of the Baretta pace car headers). I just built them one tube at a time. I started with the flange, and a collector, and figured out a general location for a collector that cleared everything. I then made some rough sketches of how to route the tubes, and keep the primary length at the 26" design length. Once you get started, it really isn't too hard. The biggest problems are figuring out how to fit the tubes in a tight location (rear header), and remembering that if you get the tubes too close together, you won't be able to weld the joints if you can't get the welding torch at them. You are almost better off getting some of the flexible tubing, and mocking it up with that.

On the sound, if you keep the cat, you shouldn't be too bad. I wasn't running a cat before, and with a dynomax muffler, it sounded great. With the headers, it was just too obnoxious.

I don't have a real good idea of how much HP/TQ I picked up. At the time, I was running a 3.4 iron-head with a TBI system, so it wasn't making much top end power. There was a definite seat-of-the-pants improvement in throttle response and mid-range power. I picked up more top-end with a swap to a MPFI intake, but it was still not pulling real hard at the top end. I have since converted to 3400 heads and intake, but I haven't had a chance to run it yet. I have the stock 3100/3400 exhaust manifolds, so I am planning to run them on the dyno first and compare the gains with the headers.

By the way, with that front header, I couldn't fit the factory puller fan, and I am stuck with an afermarket pusher. Once the car is moving, I don't have problems, but when it sits still, the fan can't push enough air to keep it cool.

Marty

[Anonymous]

I should be ok with the fans.

Do you have a link for the Beretta Pace Car headers? I would search with Google, but my school thinks Google is porn. That sounds good, but I still want to talk to a few people before deciding on a certain primary lengh.

Thanks a lot for all of your help! :P

[RacerX11]

Here is a link to the complete Hot Rod article on the Pace Car (Dial-up beware! Large Pics!!). http://tyre.serveftp.com/citationphotos/Martin%20Urbanc's%20Photo%20Album/Modifications/Baretta_Indy_Pace_Car-Article/

I don't remember the exact date, but it was sometime around '89-'90. I searched and searched on the net for a good quality image of the article, but I never could find one. I ended up hunting down a paper copy of the magazine in the archives at the local library, and scanned it in. Here are just the pics showing the headers:

[RacerX11]

Here's the other one:

[Anonymous]

wow those look nice.

i cant quite weld that great tho....

[Anonymous]

a 3.4 TDC with a bad design, not equal lengh, gianed over 1/2 second in the 1.4mi with the headers alone.

Are you sure about that? I could of sworn his were equal length....

[SappySE107]

Bad design? no way aaron, the only thing wrong with his setup was the routing under the car.