Here is a question for those who have them. I have some Doug Thorley headers i bought on E-Bay some time back (in fact I have 4 sets) I wanted to here from you that have them and get comments Good and Bad. Also what seems to be the best Muffler? Already have what looks like factory dual exhaust.

I have Thorley headers on my '85 Regal--Chev 454. They feed into one large muffler, sort of toward the street side and then out amidships of the Barth on the street side. They seem to work well. The headers, combined with Nology Hot Wires and a somewhat hotter distributor give me about 12mpg at a steady 55mph. My Gear Vendors also is a help. I recently had to replace the header gasket on the curb side of the engine. In talking to Thorley, they make their own gaskets that are designed for their headers. About $30 for a set. Thorley used to make both alloy (4130 steel I think) and stainless headers. Don't use header wrap on either one since it voids your warranty. Also, get boots for your plug/wires on both sides of your engine. Splash shields also will help with heat dissipation. BTW, I might be interested in one of your sets for my daughter when she buys her Barth. What engine/year are yours for?

PS Thorley said put the gasket on dry, no sealer. We did & so far so good.

Thanks for your input and i will follow along to the letter as i seen a post on here about the wires and ends,my Barth is a 79 with 454 but i also have a set for 350 as my last one was 78 with 350 they are in the attic in my shop so i will have to retrieve them and look.have been searching for a good used gear vendors but have not found one with e-brake so i keep on looking and hoping one day. I heard they are worth 1-2 miles per gallon.

The main reason I purchased the Gear Vendors was wear and tear on the engine. RPM's dropped from about 2700 to 2200 at 60 mph. The savings in gas will take a long time to pay the $3500 cost, but one new engine would do it in a heart beat. Let me know if you have an extra set that would fit a '85 454.
Jim

How hard is it to switch out the headers? I remember my Grandpa always talking about how he would like to do this one day, but never got around to it. I can imagine will all the rusted bolts that I would be a bit of a pain.

Also, when you switch out the headers, can you use the rest of the stock exhaust? or do you have to upgrade all of that as well?

Thanks guy
-Curtis

they can be a challenge but most of the time not to bad the easiest way i have found to do these is lift the motor home up and remove the front tires.(putting jack stands under it before going under it) and the drivers side has a panel to remove but then they are pretty well in the open. The stock exhaust can be used if they are dual like mine i will just cut the pipe @ the end of the header and attach the header flange to the existing pipe and bolt together.

What is the advantage to new headers? More power? Better gas mileage?

-Curtis

Yes! & Yes!
Jim