B16 swap. Do I really need a muffler? (Sarcasm)

Couple of things you could do...find an exhaust with shorter down pipes, or cut the pipes you have now so that the end of the exhaust doesn't come out so far...then I'd use a tight radius 90 degree elbow as the basis for the beginning of your exhaust...the 90 degree elbow would extend out to near the end of the inside of your exhaust housing and then make a 180 degree turn and that will be the starting point for your muffler or cat. That's what I did on my car and I have room for a cat and a 24" muffler (albeit barely).
 
I would have the pipes cut back and move the collector so it is just behind or at the crossmember. Then use a large radius 90 to turn the corner to get to your proposed cat and muffler.

You might find a Camaro muffler with a center intake and two outputs to either side which I think is what Hussein changed his to.

Either way cut the two main pipes back and have them re welded to the collector.
 
Last edited:
4:2:1 is the best way to go. I would think this could be a job for a muffler shop and they could help you with the rest. I know we all like to do everything ourselves...me included
 
Agreed 4-2-1 is the best but once it is shortened to fit, the benefits are all ready compromised. Talking to some guys on the honda site as well. They think I should be able to find one that the collectors are shorter. Or they said I should just go back to the stock manifold.

Odie
 
With my D15B swap the downpipe is a 4-2-1. I cut the pipe off just behind the engine, between the rear crossmember and the engine and welded in a v-band clamp. Mounted a Lambda and EGT probe just infront of the v-band.
From the v-band i went under the crossmember and then 90deg to the right --> straight piece of flex (parallel to the crossmember) --> 180deg bend --> straight piece of pipe --> straight through muffler --> 90deg bend and out the back on the rhs of the car.

I'll try find some pics a bit later.
 
One of the other thoughts is to cut before the 2 into 1 collector and put in 2 supertrapps (16 inch) straight out the middle. Going to try the shortening the 2 first. Then either supertrapp or different header.

Odie
 
Yes very. The issue wasn't as much of the exhaust as it was the header. The header was too long as the collector was about 1 inch from the back of the car. I shortened the header last night. Yes I will lose a little because it isn't perfect, but I have another b16 that I am rebuilding for a turbo so it will be short term. I was planning on going with a side inlet mufflee but like what you got. How loud is it?

Odie
 
I have no idea how long my header originally was, the motor had it cut shorter (just past the sump) when I bought it (import motor from Japan). What do you mean you will lose a little?

At idle and at low to medium throttle openings it is relatively quiet. At WOT and above 4000rpm it has a lovely scream, especially when VTEC kicks in at 5300rpm.
 
There is a mathematical equation when it comes to the length before pipes are joined to make the optimal power or torque for a given RPM. By modifying this it won't be optimal. But in our cars I don't think 1 or 2 hp/ torque will be much of a difference. I ended up 5 inches shorter where the 2 go into 1.

Odie
 
Ah, yes, of course. I kinda gave up trying to stick to OEM (and the ideal) when I decided to go the Megasquirt route instead of standard Honda engine controller :D
 
autox19 said:
There is a mathematical equation when it comes to the length before pipes are joined to make the optimal power or torque for a given RPM. By modifying this it won't be optimal. But in our cars I don't think 1 or 2 hp/ torque will be much of a difference. I ended up 5 inches shorter where the 2 go into 1.

Odie
Click to expand...

I don't understand why you just don't go straight back with a MEGAPHONE pipe. Something like this...

$_35.JPG


Not only would it look "cute"... it would sound "cute" as well... HA!

BTW... the old Hot Rodder's trick when it came to collector length was to fire up the engine and look for heat and color distortion on the purposely LONG collector,. Then cut it off about 1 inch after the markings and weld on a flange. I know yur space limited here and agree with you totally... in that ya gotta plumb the thing first and not worry about 1 or 2 pony's.

Keep up the good work and send more videos of your progress.
 
ok, I got the full mockup. TIG this weekend. pictures are from the back x2, side and top. Issues: sticks a little further out the back than needed to put the mesh back on. thinking of boxing it in to keep people from bumping up against it and burning themselves. Issue #2. you will see a 2x4 in the pics. yeah, the collector hangs lower than it. so lower than 3.74 inches. not happy with that. probably going to try to create a skidpad so if something goes under it wont tear it off, just jar and lift the car. I was also planing on upgrading to 15" rims. 205/50 in front and 225/50 in back. this will raise it a little. The other thing that was further down the plans were vicks adjustable coilovers. Now I am trying to debate which I should do first. I only have enough in the budget to do one or the other right now. With 2 daughters graduating this year it wont be until late summer or possibly winter until I can afford the other.

Thoughts?

Odie
20170303_110834.jpg 20170303_110843.jpg 20170303_110905.jpg 20170303_110934.jpg
 
Odie... I don't mean to sound critical but it does appear to come down to this one simple statement. You have a header that drops so low that you are looking to install "bandaid after bandaid after bandaid" to correct.

I believe a custom header that exits higher might be less frustrating and costly overall. Even Mark Allison's header and muffler assembly as costly as it is, might be a much better fit and less frustrating. If you haven't scared up this header returning it to the vendor with a note that is hangs too low should get you your money back or store credit at minimum.

Good luck with your decision.
 
Isn't marks a fiat header?
Looking at the other swaps, they all have headers/manifolds that exit in the same rough location. My engine/trans is actally a little higher than some. So my next conclusion was my suspension sets lower than others. Because the PO has put aftermarket springs on I am assuming this is true. Possibly even cut these as well. Who knows. That is why I am pondering the new coilovers with stiffer springs. The wheel tire combination was already planNed as my 13" are not the best of condition. Sitting for 7 years tends to kill them off


Odie
 
Last edited:
To validate my theory, could someone measure from the ground to the spot between the suspension mounts. Like where the fiat cross member bolts on.

Odie
 
autox19 said:
Isn't marks a fiat header?
Looking at the other swaps, they all have headers/manifolds that exit in the same rough location. My engine/trans is actally a little higher than some. So my next conclusion was my suspension sets lower than others. Because the PO has put aftermarket springs on I am assuming this is true. Possibly even cut these as well. Who knows. That is why I am pondering the new coilovers with stiffer springs. The wheel tire combination was already planNed as my 13" are not the best of condition. Sitting for 7 years tends to kill them off


Odie
Click to expand...

Nope...

Go here:

http://allisonsautomotive.com/wp/headers-and-exhaust-systems/

... and scroll down to the X1/9 exhaust header and muffler system. The header exits high. Mark Allison claims and supports his claim with documentation, that his system increases horsepower and can also be adapted to meet stringent emissions requirements. It does all, but FAILS the CA "visual test" and would also require a CA CAT. (Many times this is something some testers let go or are none the wiser, and others who have no life, capitalize on.)

Anyway, a viable alternative, albeit pricey. Tell them "Tony sent ya!"
 
You must log in or register to reply here.
Back
Top