Hi,
I've been browsing around the site for some time now and just can't seem to find an answer to a question I have regarding header options for stock exhaust Y-pipe.

I did a full custom 3" exhaust from the stock y-pipe/collector back. The entire system is welded and there is no cat, so I can't just bolt in a new Y-pipe. Are there any header options that can bolt directly to the stock Y-pipe, replacing only the stock the manifolds and nothing more?

Thanks a bunch for any suggestions!

Edit: I guess it would be pertenant to mention some details about the car...
It has a slightly tuned 350 that is naturally aspirated and has NO computer controlled equipment on it except the stock trans.
There is NO emissions equipment left on it and the car is emissions exempt.
FWIW!

 

How did you get the stock ypipe to fit a 3: exhaust? Wait, I know, you took a 3" pipe and cut the ypipe back far enough, crimped the 3" for it to fit onto it, right? Why would you constrict the header system designed for better flow by using the stock ypipe? I think that is why you have not found any info on here about that. Glad to hear you used 3" and welded everything. I think that most ypipes supplied with headers are 2-1/2", not the small ones that are stock.

 

To the best of my knowledge, no.

JamesC

 

A shop I was near to had a custom fit y-pipe collector to bring both pipes into
the single 3".

What do you think my best bet would be then?

 

Option 1 would be to cut the stock y-pipe off of the 3inch exhaust, and get a new set of headers and y-pipe. The stock y-pipe is really restrictive, its double walled. that means that if the outside diameter is 2inches, its really only 1 1/2 inches on the inside, which is just junk.

or, you can get a set of shorty headers of your choice, and build your own y-pipe. if u use the y pipe in the link below, then when you cut the stock y-pipe out of the system, this should be long enough to cover the gap you will have. I personally would build my own y-pipe all 3 inch from the headers back, going to be the best bet for flow.

http://store.summitracing.com/partde...5&autoview=sku

 

What I said earlier is prolly what they did. I agree w/ what Cruisanman said to get a proper y pipe. I have Hooker shorties w/ their y pipe and it works great. Don't know why your shop did not say anything to you about that. Maybe they did not know you were going to go w/ headers later.

 

Thanks for the advice and link!
It looks like this project is going to be too expensive for me right now unfortunately. I was hoping to just pick up some affordable headers and use the existing exhaust.
Oh well....
Thanks again for all the advice everyone!

 

I'm back in the market for headers AND a new Y-pipe to connect to my existing 3" exhaust. Currently installing UMI subframe connectors and the pass side will not fit due to the exhaust so I'll need to cut my exhaust anyways...might as well toss in some headers and Y-pipe!
Any suggestions?

 

dyno don, if they're still available

 

I have some hooker shorties for sale with matching y pipe. Y pipe is all 2.5 but you could cut off at y and weld 3" on as well. Let me know if interested. Its posted in classified section with more pictures.

Had high temp titanium ceramic coated y pipe has lava wrap where it crosses under oil pan. Only 300 miles after coating was done.

 

Thanks. I'll take a look.

 

Looks like these would work but I'd have to do alot of mods to get it to work with my single 3" exhaust. I also don't need the o2 sensor.

 

If you have the 3" exhaust already you would have to weld that onto where the y pipe merges together. It would be 2.5 from each header to the y then 3" after so that would flow real well. Either way i think getting rid of your stock y pipe would be best.

 

I agree.
Do you think cutting/welding in a dual 2.5" to single 3" collector would work? Basically cut off the current 2.5 collector on your y pipe and weld in a 2.5 > 3 collector.
Also, how was the fitment on your car? I have an 85 trans am w/350 and th700r4 auto trans, no emissions equip.
And what horse power might these be good up to?

 

You could get an adapter to transition to 3" but if i would do it i think just cut it off where they merge and weld 3" directly onto it to save a few bucks. I was eventually going to do that myself but engines changed lol. The headers fit really well i removed plugs dropped them in from top then put plugs back in then I loosely installed header flanges and tightened up collectors 1st and went back to tighten flanges last so everything lined up good. I did dimple one of the tubes by the flange to give better access to one of the bolts. I dont know what power level these top out at but made a big seat of the pants difference from stock manifolds.

 

Awesome. I think I'll try them out. Are they mild steel under the coating, i.e. will a mig welder work or do they have to be tig'd?
And what would shipping be to 91916 for headers and y-pipe...I don't think I need the 2.5" cat delete pipe.
Thanks!

 

Yes mig would work real well. I will get a quote from fedex in next couple days. So you wouldn't want the 2.5 portion from y to cat? I will cut that off If you wouldnt need that part it would be easier to box up and less weight too.

 

AFAIK no.

There would be little or no reason to do that anyway, given that the Y-pipe is usually about as restrictive as the manifolds. Nobody in their right mind would want to spend money and then just leave such a choke point in effect.

 

Thanks!
I don't think I'd have any use for the 2.5 inch cat piece as my exhaust is 3" all the way from y pipe back. Pretty much need only the y pipe and headers. Is the price the same with or without it?

 

Ok price is still the same 400+ ship. I will be including shorty autolite spark plugs for 305/350 stock heads, these wont put your boots so close to headers. There are 2 sets of bolts (short & long) with a wrench I made to tighten them real easy and used remflex gaskets that you might be able to reuse all included as well. Not many miles since new coating was done but a few scratches from install and un install.

 

Sounds good. Thank you!
Will standard plugs fit? And, what plug wires did you use?

I appreciate your time and the extras you're throwing in. ;-)

 

Stock plugs put the boots next to header so i found these autolites. Real good plugs. I used livewires brand plug wires. I have them for sale as well. They route underneath the headers and not over valve covers. They really clean up engine. They have heat sleeves protecting entire length of wire and heat shrunk boots. Over 100 new i would include for extra 50 if you need them.

Under 300 miles like new. Includes cap/coil

 

Very nice. Are they solid core or supression style...I have a mallory comp 9000 ignition and promaster coil which aren't supposed to use low resistance wires.

 

 

Here is pic of y pipe you would be getting. Has lava wrap where it crosses under oil pan. I will send pm with shipping info.

 

 

Thanks! I'm still deciding on the plug wires - have to do some more research on whether or not they're compatible with my ignition system.
Can you post a pic of the Y pipe showing the bend after the collector so I can see how much and what bend 3" tubing I'll need to buy to make the connection?
Thanks again.

Also, do you have an O2 block off plug for the header?

 

I would have to cut it off where pic shows to get in box. You would need a 90 degree elbow to attach to existing Y as thats whats on there now except only 2.5". I would think if you just ovaled your 3" 90 degree pipe or flattened it a little then it would weld right onto existing Y. The wires say spiral core so im guessing they are like the stock resistor style wires but definitely check to make sure though.

 

Sorry i dont have an o2 plug but they can be had cheap on ebay i see. You mustn't have the original carb setup with electronics?

 

On the wires, are they female on both ends? I have the mallory comp9000 distributor which looks like this:



Regarding the motor/carb, I put a 350 in many years ago and am using an Edelbrock 650cfm thunder/AVS series carb and performer intake and Lunati bracket masters cam with lunati high pressure valve springs.


Older picture, but I have since removed all the old computer harness and am in the process of rewiring and relocating alot of things.

 

Cool engine bay. With all that factory wire harness out of way makes it easy to work on and look at lol. Yes wires have female 90 boots on both ends. You wouldn't need the old hei cap then just the wires right?

 

Great! I don't need the HEI cap. Do you have any wire guides/clips to fit the larger diameter wires and keep them tucked away from the headers?

 

No i recommend using stainless steel zip ties to keep them tucked tight to engine. You wont need any clips or have the room for them. Out of sight out of mind and nothing covering those valve covers!

 

Great!
Lets do the wires too, but verify they are indeed the snap on to terminal and not the push into terminal style...the part number in the picture you posted seems to show them as the insertable style connector.

And is PayPal good for you?

 

Idk why that link shows wrong picture. The picture of cap and wires is what they are they will work gor you. The terminals at distributor will have tabs on top to lock into hei lockplate but you wont use those nubs. Yes paypal is accepted.