Hey all, I have a base model 66 LeSabre with the 2bl 340. The exhaust needs replaced. Is there any problem with putting dual exhaust on these in terms of cross members/clearance? Next year I would like to swap in a bigger engine if I can and it will need to breathe. If I need a different cross member, what would I look for?
I went from a single to dual exhaust on my 67 Wildcat, which isn't a far stretch from your LeSabre, chassis-wise. I didn't use a crossover tube, but two separate pipes to mufflers. The chassis seemed to be designed with duals in mind, as even the hanger locations were the same for both sides. I used a pair of MagnaFlow mufflers, so there was lots of room where the stock mufflers would have gone. No hiccups at all. Joe
I did a single to dual conversion on my 65 Special 300 with no problem. I realize the Special is an intermediate and your Lesabre is full size, but as I recall from working in a service station from 69 to 71, most cars were designed with dual exhaust in mind in those days. If you go to a bigger engine the header pipe may not work. I know the header pipe is the same for 300/340, I don't know how different 350, 400/430/455 would be. From the muffler back it should be the same, so, make sure you get a large enough diameter tail pipe and muffler for the bigger engine.
Thanks guys. I went and talked to an exhaust guy about mine and he seemed concerned that the cross member might be a problem in easily going to a dual exhaust. So I was not sure if there were different cross members used on the fullsize cars for single/dual exhausts.
I never heard of that. All the "A bodies" have clearance humps on both sides of the cross member. How old is your exhaust guy? Has he looked under your car?
He is 62, but has not done many full sized GM's. Every time I have been in there and seen an old car it is a model A ford, some 60s Mopar, or a Chevelle/ Camaro. The only Buicks I really ever see at the local shows here are Grand Nationals. When I told him it is essentially the Buick analog to an Impala he still drew a blank. Maybe he is getting forgetful in his advancing age. lol
