Requesting advice on my Bisimoto header

[wagon-r]

When I started collecting parts for my build last year, I started off by buying a used F22A Bisimoto header. Never been used, ceramic coated, and I got it for $550. What a great deal, right?

Now my build is almost done - time for the header and exhaust. Except I can't get the two parts to go together. The most the primary and collector will overlap is about a half inch, which is about 1" from the end of the tubing in the collector. Here are two pictures, which show why the tubes aren't going together - the pipes in the collector are straight, but not in the primary:



I am well aware of the leakage problem with the Bisimoto header - I have read all of the old posts. On the other hand, I was really hoping for some gains at higher rpm, and only the Bisimoto header seems to be able to do this. So, I am asking for suggestions from the experts:

1) With the primary and collector pushed together a half inch, the gaps aren't too bad. Would it be better to leave it at a half inch or would it be better to try to force it together more (for example, using turnbuckle hooks)?

2) Is this a lost cause and should I just go buy a different header?

3) I know of three other header choices. Is any of these headers significantly better or worse than the others?
a) DC Sports
b) Generic ebay header
c) F22A4 header

4) Are there any other header options besides Bisimoto that would flow well at higher rpm?

[CB7Denmark]

The other headers you listed won't make difference in gains.

The ebay headers, no just no. Low quality, low everything.

DC Sports, they are of nice quality, non leaking and crush sealings, will probably make some gains with the collector mod.
I'm using the DC Sports without any complaints, it's not leaking at all and everything bolts right up, i don't think a generic ebay header will do that.


A4 Header, i dunno really, i like to think that the DC Sports is better because the piping is of bigger diameter.


BUT, u got a bisi header? Make it work, i think you won't regret it Why not just weld it.

You could always buy any H22A header, and cut free the flange from a F22A header, bend the pipes a little to they line up and reweld, that you yield you with a super nice header.
But that is a guesstimate, but i'm thinking of doing that my self

[sonikaccord]

Buy a different header and sell me that one for $10 bucks shipped.

I think you can make it work, I mean you've come this far... If you can weld and bend pipe you can modify it to fit better.

[Joey GT-R]

This is a RACE Header....Key word in that statement is "RACE".

That being said, it's made for power, not for comfort. Leaks and or slight modification are expected. In a race car, leaky headers, super loud exhausts, missing body parts, etc are acceptable tolerances. A lot of the people who bought these headers obviously bought them for a daily driver car, and were abhorred when the comfort factor was very low.

I have a two piece header, I won't name the brand(they're out of business anyway). It was also a race header, and it had the same issues. I never complained to the manufacturer. I took it to my trusted exhaust shop, and about 2 hours later, the car was running smooth with no leaks.

[Tishock]

I think my header was even more jacked up than your seems to be. You can at least get all four runners to engage. I couldn't do that at first. I had to use a little WD-40, map torch, a lot of man handling, a ratchet strap, more WD-40 and finally using a large rubber mallet-and dead blow hammer to get it to seat. I've removed the header a couple times since then and each time its gotten easier to reassemble.

[cp[mike]]

I think my header was even more jacked up than your seems to be. You can at least get all four runners to engage. I couldn't do that at first. I had to used a little WD-40, map torch, a lot of man handling, a ratchet straps, more WD-40 and finally using a large rubber mallet-and dead blow hammer to get it to seat. I've removed the header a couple times since then and each time its gotten easier to reassemble.

i used wedges and clamps and couldn't even get my bisi runners to line up at all. guess i should wrestle it more

[jdm92_accorn]

i put mine together and had it welded around the outside with the intent of cutting it off just after the o2 bung and installing a 2.5" v-band then running a 3" 90 under the oil pan. this will give a tight seal and make it easier to remove.

[wagon-r]

Thanks, everyone. It sounds like I should go ahead and force it to engage further and hope for the best.

[19dabeast85]

I used a rubber mallet and beat on the dp. Put a rag on the dp to keep from scuffing but it won't dent. Another way that works off the car is to drop the header on a carpeted floor about 1' repeatedly dropping on the dp. It'll push its way on without damage.

[wagon-r]

I used a rubber mallet and beat on the dp. Put a rag on the dp to keep from scuffing but it won't dent. Another way that works off the car is to drop the header on a carpeted floor about 1' repeatedly dropping on the dp. It'll push its way on without damage.

OK. But I assume this means I have to pull the front crossmember to get the header on?

[Stoner51]

Have you tried expanding the secondary part? The bigger part. I have a cheap ass PLM header and it leaked like a bitch. I bought an exhaust pipe expander from harbor freight for like $15 I expanded the connections to tighten up the fit. I think you have the opposite problem but the theory should still work.
I have to use a flat head screwdriver to wedge between the them to get them to line up properly.

None of this stuff really bothered me as I got my header dirt cheap. It does leak a little when its cold. But its not very much at all I can only tell with the hood up. I could tighten it up a little but I'm too lazy and its too hot right now.

steve

[illinois_erik]

OK. But I assume this means I have to pull the front crossmember to get the header on?

if you get the 2 pieces together securely, you can raise the car up high enough to pass the header in thru the bottom to install it. This is what Ill have to do with my single piece tri-y.

[Tishock]

Just beat on it like it owed you money!

[Binladin]

Nothing is perfect, everyone should just suck it up bout the slip joints, test fit, tack n weld the 2 pieces together! Lol… I wouldn't even give it a second thought to seal up leaks.

[Jarrett]

Explain how you would weld up the inside of the joints that are butting up to the other slip joints. Or, if you'd prefer, submit a video of you doing it yourself if the explanation is too tricky.