Joe C

I'm installing a new exhaust on my 85, and thought I'd pass along, my opinion and 2-cents, on the 86-91 flowmaster, cat-less, front y-pipe. (note, stock photo - the RH flange plate is missing. it is with the supplied hardware package.)



the flowmaster is indeed stainless w/ mandrel bends. nice welds and overall, the quality looks very good. it comes with quality, stainless band clamps, vs standard muffler clamps. nice product - I give it . the y-pipe is a three piece unit. it should allow for more latitude and adjustment, vs. the solid one piece pipe.

the exhaust on my 85 is pretty much shot - it's made out of various, low cost, aftermarket parts that really don't fit well together. besides, it looks like crap!!! anyway, I'm going to install a new, front to back, stainless exhaust system, using some top-shelf parts from three different manufacturers - . I have installed a magnaflow-corsa system on my steel blue 90, without issues, so, we'll see what happens when I throw flowmaster into the mix. since the 85 does not have pre-cats, I was looking for a front y-pipe that was stainless, w/ mandrel bends. several stainless units out there, but everything I found had conventional bends. I also wanted to install a corsa cat-back system, and since the main cat's mounting flange is different, I'm somewhat forced into using an 86-91 style main cat. the flowmaster front y-pipe looks like it fit all my requirements. corsa does not make a direct fit 84-85 cat-back system - only for the 86 to 91 L98 corvette.

looking at my layout on the garage floor, I do not foresee any installation issues. I won't be using the flowmaster main cat since i'll be using a magnaflow super high flow main cat. the flowmaster to magnaflow connection looks like they were made for each other. I've used the magnaflow to corsa connection before, so I won't have an issue. I just need to secure a few nuts and bolts, a new O2 sensor, and a free weekend for installation. the only problem area is see is mounting a 86-91 rear hanger to the "C" support beam. I need drill a couple holes and i'll need to get under the car to see what's involved. I paid $210 (shipped), but hope to sell the main cat, and scrap my original exhaust and cat to recoup a couple bucks.

as I get into the installation, i'll post some pics, additional info, or any problem areas I run in to -

eutu1984

I just got the same thing this week, I am going to coat the outside with ceramic paint and maybe do the install next weekend. Good luck with yours.

corvetteronw

I installed this on my 91. Front catless Y came from a Forum member and it did have both front flanges on it. Cat is a high flow Magnaflow. Front Y did not fit perfectly as I had to spend some quality sledge hammer time with it to get the driver's side to line up.
I had to go to a shop for the final adjustments to the rear Y with H pipe and Magnaflow high flow mufflers. They had the lift, welder and heavy duty tools that I did not have.
I have installed the same items on an 86 and an 87 in my garage before with no problems. Corvette Central must have changed the way they made these.

Dt86

Looking forward to your progress. I'd like to ditch the pre cats on mine and get a high flow main cat also.