Yes you would have to slot the gasket. I’m NOT sure slotting makes it easier, BUT at least the bolt is started on the threads, THATS the bitch part, well tightening is, but at least half the struggle is done
I FINALLY got about .080 clearance between the head pipe and pan. I think the issue with clearance are the headers and the way the left header pipes are connected to the collector, the pipe that’s causing issues is cockeyed/angled going into the collector. I test fit the right header, there’s about 5 or more inches to the kick out on the pan, no mods needed there. The header with heat marks is the left one, notice how that pipe is angled.
Might be a good idea to take a measurement across the engine and oil pan how far apart those headers need to be to fit that pan. The headers may need to be tweeked some or the oil pan. Non the less it would be good to know the measurement across from one header to the other, the 1 - 3/4 may just be that much bigger. The thicker gasket may give you another .040
I had sent Mike at AM&P dimensions so he could make that valley pan to replace the valley pan with the gaskets on the 350 engine, so anyone wanting to change that can since he has the drawing to make one.
I’ve surmised it all comes down to room. The Buick 350 is physically a big block among 350’s, it’s wide, and tall. The deep skirt dictates a shallower pan, you can’t go much deeper in the sump area to gain capacity so you have to go out to the sides, which removes “wiggle room” for headers. The heads don’t help either, they continue the 90 degree angle whereas a SBC the heads stand more upright making it narrower thus affording more room, also the SBC does not have the iron exhaust passages like Buicks, you look into a SBC exhaust port BOOM, there’s the valve. Design constraints I guess. I MAY run an oil cooler, but I don’t think it will be necessary. I just didn’t want the header tube riding on the pan, they rock/move at the same time, but I don’t know how much pressure that tube was putting on the pan, don’t wanna ruin my 900 pan.
Maybe, maybe not. The bigger headers fit fine with the stock pan. Change pan design, all bets are off That’s what’s unique about us Buick guys, we have few upgrade parts available to us, and most times they need to be adjusted to work together and we do it ‘cause we don’t have many options. I’m just glad the headers didn’t need MAJOR bashing
That looks amazing! Definitely going to try that stuff next time I paint something exhaust. I have the same pan as you, but luckily I'll be going from exhaust manifolds (which fit no problem) to turbo downpipes. The driver's side fits, but I had to cut it in half and add a joint for install and removal. Not as worried about the passenger side since there's much more room with no brakes in the way!
Nice job! I bet the little massage you did wouldn't even show up on a dyno, much less anywhere else. Devon
Thank you. You can’t see the smashing of the tube looking from the drivers side, you’d have to be directly under the car and staring at the pan and pipe. LOOOL I noticed on the bitch bolt, TA already pressed a divot in the pipe for clearance so you can at least GET the bolt in the hole of the flange
I painted the headers a few years ago when I first got them from TA, I just scuffed them with a red Scotchbrite then sprayed ‘em down with lacquer thinner and put just two light coats of that paint on. Fast forward to now, I’m really surprised how durable the paint is, it never discolored, and they have been banged around a lot going in, out, in, out, no flaking, just scratching. Only reason I blasted them was to roughen up the surface to prep it for a fresh coat. And if I do scratch them, no big deal, I only have 12.00 in paint
Headers look good, like a satin nickel color. Check those manifold type gaskets with the welded header flange to see if they will seal up. Those header flanges are not flat like iron manifolds.
Actually they’re quite flat and true, I used my Dads old aluminum level across them, I’m almost tempted to run no gaskets, but I don’t wanna get back into this if they don’t seal. Thank you on the headers
Ah I realized the way I wrote that made it seem like I'm running a downpipe from an exhaust manifold, what I meant to say is I'm switching from manifolds to turbo manifolds/downpipes. So still using the Burton turbo pieces! Will update the thread soon though, my deadline for having the car on the road NA is October Hope your header install goes ok! I was wondering on the middle bolt, can you use a hex headed bolt (cap screw) and then use a ball end hex on it for more clearance when tightening?
With these 1 3/4” headers what little swing room was available with the 1 5/8” is gone. By notching the bolt hole and then being able to “hang” the header on the bolt is half the battle, actually 3/4 of it
