I have a '91 Camaro with a 305 L03 engine and I want to add headers and a y-pipe, delete the cat and the rest of the exhaust will be 3" single exhaust into a flowmaster 40 series muffler. I am considering two options for headers and y-pipe: Option 1: Summit G9005 ($90) 1.5" header into a 2.5" collector into Hedman y-pipe ($103) with a 2.5" inlet and 2.5" outlet. Total $193. Option 2: Hooker 2460 ($140) with a 3" collector into the Hooker 16767 y- pipe ($240) which is a 3" inlet and I will have to customize the outlet to be 3". This option is at least $400 before the modification to the y-pipe. Future plans are Edelbrock Performer intake, gears, and a mild cam. So, does anyone know how big of difference it will be between the 2.5" or 3" y-pipe?

2.5 to 3inch you will have better flow of exhaust. Gives you little bit of power. I mean not alot to notice but will make the engine breath w/o the restrictions.

don't bother with the 1.5" primary headers unless you only want them to say you have headers. they are restrictive on a stock engine.

The downpipes on the 16767HKR are 2.5". The only thing that is 3" is the flange that bolts to the 2460HKR collectors - it's an immediate downsize.

I'd say don't bother with either one of those choices. The 2055HKR are 1-5/8" primaries, and the y-pipe that comes with them is the best off-the-shelf piece out there. No expensive modification needed.

How's the 2460 ypipe?

As delivered? Fine for a stock cat-delete LO3 (which is the market they were shooting for).

So it's pointless to put it on a built 350 or a mild 383? I found a great deal on a like new set of 2460 and the matching y-pipe but was wondering if it would be worth it. I would love to go with long tubes but I also plan on lowering the about an inch more which will make longtubes a bad idea. What set of longtubes tuck in the best?

Thanks for the input guys. I agree the Hooker 2250's are a better header and y-pipe combination. However, since I had the misfortune of getting married, I don't think I will be able to convince my wife I need to spend $815 on headers and a y-pipe.

Seriously though, I am only going to be doing mild modifications in the future, being an intake manifold and a cam swap into my 305. So I think bang for the buck the hooker 2460 setup for $400 might be the way for me to go.

While I agree the 2250's flow better, I would only imagine maybe a 5-10 max increase in h.p. over the hooker 2460 setup. Does this sound about right?

If I wasn't married and full disposal of my bank account, I would also have built a 383 with full length 3" headers with a custom y-pipe. If you spent the time and money to build a 383, I would not skimp on the exhaust.

Isnt a 2460 header the exact same as a 2055 minus air equipment. I know the 2055 has a much better ypipe then you can get for the 2460. But you take you car into the shop they could whip up a good 2.5 - 3 inch ypipe for cheap im sure. What performance gains would you see on an engine with roller rockers, ported slp runners, ported eddy base. I'd like to see 250 rwhp with that set-up?

Go with the Hooker 2055's and Y pipe. What's the point in all that work to only use smaller primary headers and go from 2 1/4 to 2 1/2 piping? If you go 3" then you will make room for other mods later that will work best together.

I'm removing emissions. 2055=2460 doesnt it? The 2055 just has a.i.r hookups..

No, they are not the same. The 2460HKR uses a thicker gauge tubing for the primaries (meaning less flow area, since tubing size is listed as OD), and the collectors are completely different.

thank you. i just learned something new.

If you did get the 2055's you can either cap the ends on the smog tubes (that's how I recieved mine) or you could also have them cut and welded pretty easily. You could also look at Dyno Don's which have good reviews around here or checkout the Headmans.

My mistake, I was looking at the ceramic coated headers, the black painted 2055 are only $459 from Jeg's. The hooker 2055 are definetely the way to go. However the description from Jeg's say they fit '86 to '90. Will they fit a '91 RS 305? Has anybody else tried that?

The 2055HKR are only a direct fit for '86-'90 TPI single cat application. They will "fit" any SBC 3rd gen engine & chassis, you just need to modify the rest of the exhaust (which is why they don't list them for other applications).

I'm running them in my carb'd '82, for instance. There is a picture of mine after Jet Hot coating in my vBGarage.

To just "cap" the a.i.r. tubes you just unbolt them and use a pipe thread block?

Yes they do fit a 91 RS just fine. I have them! Plan on getting a 3" Cat or pipe and a 3" catback.

I have the 2055's on my 91 TPI.... It originally came with 2 cats, but only had 1 when I got it, and I added a high flow... as stated, air tubes can get capped or cut off / welded...

Call Jet Hot, they have some deals, I got mine for a smokin deal from them...

& Breslin locking bolts, as oppsed to the jigsaw puzzle locking stage 8....

Raf

Well, I have the 9005 headers with a custom y pipe. The shop did 2.25 from the collector to a 2.5 y-pipe, to my flowmaster. Felt a significant difference between 2000-3500 rpm. I've been playing with a chip kit and strongly recommend getting chipped after the exhaust. Now I have power off idle, cruising and it actually pulls in 4th gear.

link of exhaust, header pic will come later

http://s15.photobucket.com/albums/a3...d/Camaro%20RS/