Looking for what you guys run header wise on a 1968 Oldsmobile 98

 

Nobody makes headers for the 1965-70 Olds full size cars. There is zero demand for these and due to the location of the steering box and linkage, routing them is nearly impossible. Just get the repro dual exhaust manifolds that clear the steering box. A Ninety Eight is never going to be a drag car. The stock manifolds will be fine.

 

To replace the exhaust manifold on the driver's side, does the engine have to be removed or can it be done with the engine in place?

 

You can do it with the engine in place.

 

Joe - confirmed with the mechanic and he did say that to replace the manifold and gasket it can be done in place. He did warn me though that there is a 50-50 chance that one or more bolts might crack. If that happens to drill it out and put a new bolt, he would have to get the engine out.

 

Soak the exhaust bolts with PB Blaster every day for a week before removing the exhaust manifold. Spray it with PB Blaster and slightly tighten/loosen each bolt. After a week they will come free without breaking..

 

Dropped my 1968 Olds 98 convt at the mechanic last Saturday to replace the exhaust manifolds. He soaked the bolts over the weekend and on Monday was able to remove all the bolts without any breaking. He had to lift the engine up a bit to remove and replace the manifolds. All done he charged me 3 hours labor for this effort. On Wednesday the car was on a flat bed over to the muffler shop for them to redo the exhaust pipe from manifold to the muffler. I will post some pictures later today of the engine bay. The exhaust manifolds were ordered from Fusick. Cost was approx $500 for manifolds, gaskets, bolts, locks and shipping.

 

I have also had good luck with Kroil, the key is patience. I don't even bother to try to loosen or tighten anything for 5 days or more. I just slightly tap each bolt head with a small hammer, I think the vibrations let the oil get into the threads.

Then when you loosen or tighten do not gorilla it, some force but if no movement or slight force KEEP oiling it. Then come back the next day and oil it and try again.

Remember the mechanic needs to make money he cannot take a week to get bolts loose, you can. I stay away from heating the bolts unless all else fails. I do not care what they say it will not crack. They use heat because it is quick. You need patience.