octanejunkie

My recently acquired delta 88 is from june 1972.
Its a 350 with a three speed column change. It has a recently rebuilt original 2bbl carb. It is completely original to the car and still has everything factory fitted.
Question is, being from the UK, i'm not that familiar with all the variations. What kind of motor is it?
Will junking all the emissions stuff have any improvements on performance or economy? Can i alter the timing and get rid of some of the hoses etc.?
I'd like a tidier looking engine bay.
What kind of easy, cost effective things can i do?

In the UK it doesn't have to have any kind of emissions check.
Car runs very nicely at the moment, and is surprisingly perky for a big old girl.

Or should i just leave it..?

captjim

To be honest, you will probably do more harm than good by deleting items. It is all pretty basic, EGR, PVC, a few temp switches for better cold operation. Your best bet is just to get it tuned perfectly. depending on the fuel available, you may be able to bump up the timing, and you can re-curve the distributor. Keep in mind, it is a low compression engine in a big-azz car, it isn't going to be a barn-burner.

hookem horns

All depends on what options it came with and what you want to keep functional. Look at the chassis manual (available online) to see what the various vacuum lines do before yanking, but you probably NEED these vacuum lines at minimum:
Brake booster
Transmission modulator
Distributor advance
PCV (plus vent on the other side)

If its a factory air conditioned car but it's not working (pretty common), you can free up a lot of space taking out all that stuff. For A-bodies you can buy a delete panel so you can remove the evap unit but still keep heat, but not sure if something like that exists or would have to be made/modified for the big cars.

octanejunkie

Thanks for the info. The engine runs perfectly with no flat spots or hesitation. Has enough power to smoke a rear tire pulling away! Lol
I'll probably leave well alone. May upgrade to an electronic ignition though for reliability's sake.
Air con is still attached and working, though needs a bit of gas.
I was quite surprised to find that there is only one exhaust silencer on the whole system, but from the box back, it seems very narrow. Would a more free flowing exhaust help? Be nice to free up some extra v8 burble.

joe_padavano

What emissions stuff? The evap cannister recovers gasoline vapors that would otherwise be vented to the atmosphere and pipes them back into the carb. Granted it's a small amount, but why throw away any gasoline? There is no performance impact assuming the system is operating correctly.

The PCV valve likewise has no performance impact and should be retained.

There is no EGR valve on a 1972 Oldsmobile with the possible exception of some cars sold in Calif.

The only other emissions equipment is Transmission Controlled Spark (TCS). TCS is an early form of NOx emissions control and frankly is the one thing I would remove. TCS inhibits vacuum advance to the distributor except in high gear. The result is poorer low-speed economy and performance. I usually remove the system and run the distributor vacuum advance directly off of manifold vacuum. This does require you to readjust the carb and distributor advance from factory specs. If you don't want to do this, don't remove the system.

That's all there is. And to answer your other question, the engine is an Oldsmobile-sourced 350, which has exactly nothing in common with a Chevy 350, a Buick 350, or a Pontiac 350. All four motors are completely different designs with different bore/stroke, different castings, different internal architecture, etc.

Fun71

1972 should be pre-EGR but it would have the transmission controlled spark setup that prevents any vacuum advance until the engine is up to temp and trans is in high gear (early emissions control system). I would bypass that switch and run the vacuum advance straight to the vacuum source so you have VA all the time. The engine will perform better this way and there won't be any detrimental effects.

edit: Joe and I were typing at the same time and he explained the TCS system better than I did.

joe_padavano

Just to clarify, the TCS inhibits vacuum advance at any engine temperature up to overheat conditions. The purpose of the thermal vacuum switch is not to sense when the engine is up to temp, it's to sense when the engine is overheating. The problem is that even in high gear, the vacuum advance is sourced from ported vacuum. Once the coolant temp gets above a preset point, the TVS bypasses the whole advance system and connects the vacuum advance diaphragm directly to manifold vacuum.

octanejunkie

So, to remove the TCS, are there any other adjustments that need doing apart from some vacuum re routing?
Is there a guide on here anywhere on how to do it?

octanejunkie

Right, i popped the air filter off, traced the vacuum advance from the dizzy, pulled it out of the TCS valve on the front of the engine, connected it to the front of the carb on the outlet about halfway down. Then i blanked off the open port on the TCS. Does this sound right??
Went for a drive and the engine seems a little smoother and picks up a little better. Not a HUGE improvement, but i could feel it. Will this help the economy slightly too?