nyelectrify

I have picked up for very little a 2004 stock c5 full exhaust with manifolds and cats and mufflers including gaskets and doughnuts.
Will these fit a 1998 regular targa top c5???
These were new take offs with about 1 k on them
Am thinking about swapping out the fronts with cats since these have 1k on them and mine have 60 k on them.
Will they fit and do I gain anything because of the miles difference??
If not I will sell the whole system to someone who may need them

mitchcole

2004 has slightly better manifolds, but the addition of the pup cats means a little more restriction than your existing. better performance? I doubt it. At 60K miles, your system should still be working great. I was still only reading 37 ppm HC after the 190,000 miles on the stock cats.

Other issue: the passenger side air injection point is further forward by 1 cylinder - so your air injection system won't connect. You can buy another injection tube of that 2002-2004 series, but they're a pain to replace. I ended up pulling the intake (I bought used headers for the wrong year and ended up in this situation)

One more note: the cat pipes through the H pipe will fit onto your existing manifolds if you wanted to. Then you could simply sell the manifolds. Seems like a lot of work with no real benefit though.

nyelectrify

Thanks a lot, looks like will be putting them up for sale!!
What do you think would be a reasonable price to ask for them as a complete set up??

ssrallyred

Just a side note you can get 80-100 bucks for each converter at a scrap yard if you dont do anything with either system, just sayin

nyelectrify

Sounds like a stupid question but don't the cats get more plugged up with more miles driven??
Thought because of carbon build up it would restrict it more??

Also know that the scrap yards will pay monies for those cats but would be a shame to scrap a system with 1 k on it.
If its only worth that then I will change out the cats and h pipe and save the mufflers in shed so if I decide to back to stock I can since I don't have the stock mufflers for the car.
And then scrap the original system of the cars cats
Have a lift at house so no issues in working on it.

Pulled the o2 sensors on the car and replaced them about 500 miles ago and they definitely needed it, looked burned up and in fact car ran better afterwards evn though showed no codes.

nyelectrify

But will see if anyone may need on forum in the for sale section. That's why I was asking what would be a fair price to be listed............was just asking.
Or does everyone usually just toss these???

mitchcole

Don't toss them - those things are worth money. The cats won't plug if the car is running right. They're a honeycomb design that minimizes restriction and turbulance. They're really nice. It would be a shame to give them to a scrap yard. As for fair price: somewhere between $200 and $300.

nyelectrify

It may be worth holding onto then, even if I change out the h pipe with cats. Whole thing was 100 bucks plus some fuel.............and they do look tottaly brand new!!!

nyelectrify

When you pulled the intake were you replacing it with a ls6 one?? Because I will be doing that at the end of the month ??

rebelheart

The exhaust manifolds themselves would be the only thing worth changing if you are looking for a bit more power.

nyelectrify

How much a pia is it to change those???

nyelectrify

.????? Any input on the pia level??

SteveDoten

2001-2004 cast iron ex. manifolds will NOT work with early Hpipes

lionelhutz

I was just going to post the same. The newer midpipe assembly will not bolt to your manifolds. You can save the trouble of trying.

You'll likely get more at the scrap yard for the cats then selling here. Try $200 and expect to come down. There are lots of take-offs around. Mine is just sitting in the shed.

03WhiteConv

There are still some folks out there that want to keep their cars stock and that mid pipe is $1200 at the stealership.

Cars that don't get driven much, like mine before I bought it, can have the cats go bad. I was told if they never get good and hot, the build-up doesn't burn off the catalyst inside and can plug it up. there is only about 2psi of pressure there and mine was so plugged it was running at 15psi. Only option is to replace if you wanted it original.

Obviously you wont get anywhere near the dealer price for the mid pipe but it is sellable. Probably not on this forum though, seems like most here are modding the cars so very little interest on original parts.

nyelectrify

But my suplamentary question then is..... ........
Since I'm putting on a ls6 manifold will that make it easier to change the pipe to the manifold if I change out the manifolds for exhaust, supposedly gaining a little by changing them, so then I can use the newer h pipe then with the newer cats????
And is the pia level up there to get it All unbolted a d bolted up, or are there any bolts for the 98 year that are prone to break when trying to remove???
Sorry for the real mouthful of a question
Just trying to figure out if worth the effort since my buddy and I wrench everything all ways besides him being a retired Chevy mechanic

lionelhutz

Stock manifolds are pretty easy to change. The AIR pipe is easy too if you have the intake off.

nyelectrify

Can the air pipe be ordered from dealer orone of h venders off this sit???