I have a 87 305 TPI that currently has the SLP Y pipe and 3" cat back system. I never bought the matching headers when they where available. Do any current headers match up to the older SLP Y pipe?

 

Contact Dyno Don. He makes headers and Y pipes for both his headers and SLP headers.

 

How do you have the SLP Y-pipe and SLP cat back on the car if you don't have the SLP headers?

 

They were also listed separately for purchase in the catalog. I also have the y-pipe with out the headers.

 

I'd have to go back and look but didn't SLP offer a Y pipe for manifolds or was that someone else like mac? Can't remember..

If anyone has a nice SLP Ypipe for the 4n2 one headers they'd sell, let me know. Preferably for a dual cat setup.

 

Since the SLP catback fit the stock exhaust in front of it, any headers that fit stock exhaust will fit it.

Subject of course to which stock exhaust we're talking about. Since there are various connections that were used over the years between the cat and the I-pipe, you might have to change that detail, depending on what headers & cat you end up with. Same between whatever headers and whatever cat.

 

No, there are none, mine won't fit the SLP y-pipe. But you could modify the y-pipe to make mine fit.

 

yes you are correct SLP had the y-pipe for stock manifolds.

 

It doesn't matter anyway because an SLP Y-pipe that fits the stock manifolds wouldn't have fit their headers. You'd had to have purchased the headers with their header-specific Y-pipe for them to work together. And if you'd have purchased that combo, then you wouldn't have been able to use just the Y-pipe with your stock manifolds all this time, and now you'd still be searching for headers w/Y-pipe.

Don's are the best and closest you'll find to SLP. Like he said, your existing Y-pipe might be able to be modified to fit his headers. It's apparently stainless, so it might be worth looking into doing that.

But for the Y-pipe record:

It's cool to know SLP offered a Y-pipe that fit stock manifolds, as well as its headers w/Y-pipe (a standard shorty design, and a Tri-Y shorty design?), and a cat-back, none of which are still available.

MAC also offered all the same goods, a Y-pipe that fit the stock manifolds, headers w/Y-pipe, and a good-sounding cat-back, but MAC closed up around the time of covid, so none of those are available anymore either. A motorcycle shop in SoCal bought up all of MAC's warehouse stock and sold it on ebay a couple of years ago, including one Y-pipe.

Magnaflow still offers a Y-pipe that fits stock manifolds. They've been saying for years that it's being discontinued it, but it's still available, which must mean people are still buying it.

And Don's products are still available, but for how much longer, only he can say. I'd have to believe he enjoys it, or he'd have driven off into the sunset years ago. We'd have been calling out, "Don! Come back!" But he'd have kept going and wouldn't have slumped over in his racing seat with the car heading over a hilltop.

 

There's an old Summit catalogue

 

Thanks for all the insight.