Header options - 4-1 or 4-2-1?

[91mr24u]

N/A 91 MR2 here...5SFE. The car doesn't make much high end power - from about 5k-6k, so I usually shift it at 5k. Question is...which would be a better power adder altogether, a 4-1 header or 4-2-1? I think 4-1 will add top end power and 4-2-1 will add low end power...trying to figure out which would be a better option. Not many header options, and the only 4-2-1 I could find is this:

http://cgi.ebay.com/ebaymotors/MR2-J...spagenameZWDVW

They advertise it as 4-1, but it's not...so I don't know.

[tHa kNiGHt FaLL]

wow i never seen that before... that kinda coo...

its tube diameter and length that generally decide the performance of it.

long and thin are for torque (high end)

short and wide and for hp (low end)

but remember when you change exhaust to boost your high end... your gonna loose on the bottom... and the 5SFE already lacks some serious low end

[MR2Jedi]

Those are nice....
I would guess from what Drew said, they would be more for top end.

[91mr24u]

I was out driving around yesterday trying to really get a feel for the car...the gears are so short. I've noticed that while just cruising at 60 on the highway...at 3,000rpm. But when I step on it, shift around 5,500 and then it will be at about 4,000 in the next gear. So I'm wondering if getting a header for high end would be better.

I was thinking of getting a HKS super mega high flow filter...maybe that would help a bit.

[MR2Jedi]

Be better than what ?
Your best bet is to have a less restrictive intake and a free er flowing exhaust.(from ex. manifold to tailpipe) You may pick up between 7 and 15HP . and better throttle response.

[91mr24u]

Would it be necessary to run a muffler, or could I just run the header/downpipe? How much of a power gain does a muffler really add? Well, I guess they would only be used for backpressure.....

[MR2Jedi]

Add just a muffler by itself ? Not much -1 or 2 hp over the stock dual outlet muffler. The combination of a less restrictive intake , a header and matching pipes wil give you the most gains in that regard.
HP is not cheap....

[rollatuner110]

It will depend on your needs such as your driving habits. Do you drive city streets a lot or do you drive on the highway a lot. 4:1 would be perfect for the highway where passing would be easier. 4.2:1 would be good for going from stoplight to stoplight.

[91mr24u]

MR2BAD, I meant how much of a difference would it really make adding a muffler with header...or could I just run a straight header and downpipe with no muffler.

Also, I drive highway everyday, 25 miles to work and 25 back. So what's a good 4-1 header?

[MR2Jedi]

Originally Posted by 91mr24u

MR2BAD, I meant how much of a difference would it really make adding a muffler with header...or could I just run a straight header and downpipe with no muffler.

Also, I drive highway everyday, 25 miles to work and 25 back. So what's a good 4-1 header?

It would be illegal to run without a muffler, not to mention loud as hell.
A header and a good magnaflow muffler would be a good mod.As for how much hp gains,I would guess maybe 8-10. A less restrictive intake-like a K & N cone filter- would compliment that set up and make a few more ponies. maybe 15....Once again, HP is NOT cheap..