Impulsive 3.8 swap.


Caustic Cacophony
Lost data in this thread: KB 1xb cam had a wiped lobe. I replaced it with a different Elgin cam and had to pull the heads while the swap happened for guide shortening and seals. Learned that it has hyper pistons in it with more compression.
Then more time passes and this machine was stolen and recovered in one night. Crazy stuff, I'm prepping the engine to get pulled for a leaky rear main seal and a mystery vibration that is new. I'll repair two cracked header spots while the engine is out.
F*ck 😆 over a year I am busy though. Removal was easy until it wasn't for clearance in the general custom oil pan to cross member area. Engine will probably have to be reinstalled without the oil pan and put that on later. Other than the the oil leaks and one loose bell housing bolt everything looks good and no sign of the vibration cause yet. Next up: removal of oil pan and rear bearing cap for new rear main seal and oil pan gasket. The one I am removing is a really nice thick cork RJC gasket worked great on the tweaked custom oil pan unfortunately I only have a thin cork felpro this time. Got to pull the passenger side header and weld up the cracked primaries and a spot on collector that just cannot be done on the car.
Pulled home built rear sump oil pan off, just a few slivers of cam bearing babbitt from the cam swap a few years ago was only foreign matter, it was clean and oily otherwise. Pulled the rear main cap and this block has a rope seal, now it makes more sense all the oil under the car. I didn't see a culrpit for the vibration yet still.
Removed the passenger side header, it's the worst for repairs but everything on exhaust was broken somewhere from the damn vibration.
I've never seen a Buick V6 header like that. Why so long? I hope you get that vibration figured out. Was the vibration while driving or all the time?
Torque boost I suppose these headers are really nice they were/are ceramic coated, this car has a lot of tricks these long tubes are some. Vibration occurred after revving the engine up very high while reversing in a road rage scenario. It's very annoying while at highway speed cruising, the engine rpm sits right at the vibration point.
Welding repairs are done, this is the entire exhaust system given this is a small car.
Back onto the engine work & figuring out vibration.
"In stock" turned into a back order until mid July for SCE Gra-form exhaust gaskets, canceled that for SCE embossed copper that were definitely in stock.

Then I brought it back to the home garage and drove it to work today. The vibration had to be the entire exhaust broken.

I had this at Waynesburg Flashlight drags back in June.
I rebuilt and swapped a 390cfm Holley 4bbl in place of the 600cfm Holley carb, the 390 sure drives really nice around low rpm even on the single plane KB intake. The 600 developed a off idle stumble and low speed backfire that will not go away, it's just old and worn out but it runs a lot better wide open with the 600 on.
I'm a believer in small carbs for stock to mild built Buick V6's. High compression (above 10.5:1), ported heads and cam need a 4 barrel carb with more cfm and higher shift points to take advantage of those mods. Kenne Bell used to include a Rochester 2 barrel carb adapter for mild engines when you bought the Kenne Bell Number 1 intake manifold. They also sold a 320 CFM 2 barrel Rochester carb for that intake. They later started recommending the 390 CFM Holley.
If I trade up or see a 450cfm Holley for sale I'll grab it and try that. It's so weird feeling the power band "come up" on this cam vs the original KB cam, it pulled from idle to when you lifted.
This has a 214/224 flat tappet I got from EK02, it's a good one, I'd like to swap this engine in the blow through Regal for a bit.
Please keep updating the progress on this car. The 5 speed definately helps keep it in the power band. NA cars with stock highway gears and automatic transmissions with low stall speed convertors just bog and seem to gain nothing from a switch to 4 barrel carbs.