[unclescratch]

I have 17748 mufflers (center inlet/offset outlet) from my header collectors and straight 2-1/2 inch pipe back to the rear axle. Dynomax tells me their 15802 tailpipes will not fit unless the mufflers are offset/offset. Can anyone confirm that Dynomax is correct?

My experience tells me that some of the mfg. reps just read from catalogs and don't really know.

Vehicle is 1965 GTO.

Thanks.

[goatless]

Every A-body exhaust system I've ever seen has offset/offset mufflers.

[unclescratch]

Perhaps you didn't notice where I had described the system I am using ??

[David Jones]

Seems you have 2 options, if your desire is a straight bolt on deal.

1. Try it. Your headers outlet location might make what you want to do work. Maybe.

2. Follow Dynomax's advice. Just thinking about it, a center inlet muffler moves the muffler over towards the driveshaft compared to a offset inlet. There's not much room as it is with the standard offset/offset A body muffler.

I have Dougs headers on my 69 GTO and they line up and work perfectly with my 17749 Dynomax mufflers. Offset/offset.

Given a good muffler shop and some cash and the inability to return the 17748's for the correct muffler, anything is possible.

[Formulajones]

Unclescratch, Dynomax is correct. On the A-bodies you need an offset/offset muffler for the tailpipes to fit as they should. All the tailpipes manufactured for A-bodies (Flowmaster, Torque Tech, Pypes, Dynomax etc..) all require the offset/offset muffler.

You can get away with an offset/center muffler setup but the inlet pipes at the muffler will need to be bent at about a 30 degree angle, making the mufflers sit slightly crooked to accept the tailpipes so as to allow the tailpipes to sit in their factory location.

[unclescratch]

I don't have a stock set-up to look at, but I am supposing that the 17749 (offset/offset) muffler is installed with the inlet offset close to the driveshaft and the exit offset close to the outboard side of the vehicle? Yes/No?

My tailpipes should arrive today. The 17748's are in place. I'm about to see if things line-up. Stay Tuned !!!!!! or Place Your Bets !!!

[Formulajones]

Correct.

[sts]

ttt

[sts]

one more try

[unclescratch]

When was the last time you took an aftermarket, non-stock part out of the box and it fit just fine?? Well, the butt scores aren't in yet, however I took these tailpipes out of the box, slid beneath the car on my creeper, and in less than 5 minutes I was back out and looking at the 2-1/2 inch pipes from the back bumper. Amazing! I still have to install the tailpipe hangers and tighten all the clamps, but holy cow, batman, this is looking good so far!

[unclescratch]

Yes/No? = Correct ???? I'm still working on this one, but thanks for your interest.

[Formulajones]

Originally Posted by unclescratch

I am supposing that the 17749 (offset/offset) muffler is installed with the inlet offset close to the driveshaft and the exit offset close to the outboard side of the vehicle?

This is correct

[unclescratch]

Ahhh, Thanks.

And since I'm here, finished the install today. Had the same experience as that fellow who posted (with photos!) on Summit regarding the alignment. Just eyeballing the tailpipes, it appears that the inlet and outlet are parallel. But perhaps they shouldn't be. When installed the tailpipes point in somewhat towards the center of the vehicle. That fellow @Summit Racing must be a bunch younger than me, he sectioned/welded the pipes to fix his, I found a way to live with mine. Go figure.