Do carbed cars need or not need thicker Oil?

[SuperFast]

Thinking of going 10W-40 in the 84 2.8 Camaro in the summertime, for when temps really ratchet up. it seems as though my car does ideally on the two tried and true (and outdated, but my car is an 84, 27 years old, makes me feel old but nice car) principles of:

1. change it every 3000 miles (something to do with being carburated? so even new SM or SN oils might be same rle on this engine, due to the way the engine treats the oil? idk) and

2. use a thicker oil in the summer (maybe this engine likes its cushion. It sure is right from the golden age of "thicker oil" to protect moving parts from wear with a thicker film, particularly in hot hot temperatures)

I have 10w30 in there now. I also changed the oil filter and not the oil, due to my apartment complex. Added one quart of hi-mi 10w30 , STP first and last time it was so gummed up i couldn't get it all out of the bottle, and a pint of MMO. In a week of starting the car up almost every day and letting it idle a half hour or more to keep the gas in check and let it RUN, all smoking on start-up has stopped, except for if it was cold and condensation smoke. oil nor coolant has also not consumed anything, and the PCV valve problem was a laughable scare, as i thought i had a head gasket problem, good thing i don't. the pcv valve was clean off, that will do it for the smoke

I am now "Due an oil change" but I'm honestly not going to worry about it for a couple of months. PYB SM is right on the shelf next to PYB SN, so im not sure to go API SM or SN (?) but my oil i like that's hi-miles is SM, and this time ill add the MMO and the Redline zddp additive all 2oz. of it as per Radman,.........

my question is yes or no to go 10W-40 when the ambient temp gets to about 100 or closer to 110 degrees and im driving the car. and why or why not. Thanks

Got right about 163,000 miles on here, 163736 last time i looked, it has 5 digits so its either 63000 (unlikely,) or 163,000 or 263,000 miles. Runs strong, this engine here. no more smoke on startup either so something is doing something, maybe it just needed to be ran. Ii also put healthy dose of MMO in the gas, way more than im supposed to. yielding good results. sat for months now its an every other gay grocery getter, the idling makes up for my short trips, its still HOT out here tough and yes i let it run a half hour or more every time.. sludge already IN engine, too. still runs strong. what to do ?

 

[Zaedock]

I typically run SAE30 or 10W40 in my Jeeps during the summer, but they get beat down on the trail. I think if your cooling system is up to snuff and your carb is in tune, then 10W30 is fine for a daily driver.

Starting your car and letting it run for a half hour is a waste of gas. Just drive the thing.

I wouldn't use any additives either. Especially that goopy STP polyolefin(sic) doo-dee. Just add fresh oil and drive it. PYB, QS, or Formula Shell (I'm a SOPUS guy) would serve you well.

 

[fdcg27]

Back in the day, the usual remedy for fuel dilution with a carb was more frequent changes, not a thicker oil.
I believe GM recommended a 5w30 for this engine, and specifically warned that 10W-40 should not be used.
A 10W-40 of today would certainly cause no harm, though, and I would use it without hesitation, although a 10w30 should be fine as well.
You could try 10w30 for a while, and if consumption seems high, then try a 10W-40.

 

[Eddie]

I also think 10w40 is not the best choice. I would run 10w30 dino and change per factory recomendations. 10w40 was on the do- not-use list by GM & ?s due to the required VII that broke down in hot temps.

 

[CATERHAM]

GM spec'd 5w30 for your car and a modern 5w30 is more robust than the 5w30's of the early 80's and that's what I'd use.
I doubt you need more ZDDP than what's provided in todays 5w30's in your well worn Z28 but if you already have some RL Break In additive use it.

 

[eljefino]

The STP and MMO are counterproductive. So is the idling.

Just drive the car. It has a computerized carb, that if working right and the choke is pulling off quickly, won't fuel dilute your oil all that much.

 

[AlienBug]

Originally Posted By: SuperFast
sat for months now its an every other gay grocery getter


I guess we know what part of California you're from.

 

[SuperFast]

Originally Posted By: CATERHAM
GM spec'd 5w30 for your car and a modern 5w30 is more robust than the 5w30's of the early 80's and that's what I'd use.
I doubt you need more ZDDP than what's provided in todays 5w30's in your well worn Z28 but if you already have some RL Break In additive use it.


Why not just use 10W30 ? coulda swor it specd 10W30 not 5W30

and im never using STP again, it glopped up i couldnt get it all out and it said it had ZDDP in it, the pint of MMO was a Oil Additive forum idea to "clean" and all smoking stopped, even with STP and MMO counteracting

should i use no more MMO as well as no more STP i wouldnt use STP again anyway ?

 

[mechtech2]

The smoking was attenuated because of the thicker end result, with the STP.
Oils had a lot of ZDDP back then, and now do not. A NON energy conserving oil should have more nowadays. And that means a 10-40 or 15-40 .
I'd forgo the additives and try a 15-40 HDEO. You DO live in warm California. And you have an engine that smokes and needs special consideration.

 

[electrolover]

Originally Posted By: SuperFast
Thinking of going 10W-40 in the 84 2.8 Camaro in the summertime, for when temps really ratchet up. it seems as though my car does ideally on the two tried and true (and outdated, but my car is an 84, 27 years old, makes me feel old but nice car) principles of:

1. change it every 3000 miles (something to do with being carburated? so even new SM or SN oils might be same rle on this engine, due to the way the engine treats the oil? idk) and

2. use a thicker oil in the summer (maybe this engine likes its cushion. It sure is right from the golden age of "thicker oil" to protect moving parts from wear with a thicker film, particularly in hot hot temperatures)

I have 10w30 in there now. I also changed the oil filter and not the oil, due to my apartment complex. Added one quart of hi-mi 10w30 , STP first and last time it was so gummed up i couldn't get it all out of the bottle, and a pint of MMO. In a week of starting the car up almost every day and letting it idle a half hour or more to keep the gas in check and let it RUN, all smoking on start-up has stopped, except for if it was cold and condensation smoke. oil nor coolant has also not consumed anything, and the PCV valve problem was a laughable scare, as i thought i had a head gasket problem, good thing i don't. the pcv valve was clean off, that will do it for the smoke

I am now "Due an oil change" but I'm honestly not going to worry about it for a couple of months. PYB SM is right on the shelf next to PYB SN, so im not sure to go API SM or SN (?) but my oil i like that's hi-miles is SM, and this time ill add the MMO and the Redline zddp additive all 2oz. of it as per Radman,.........

my question is yes or no to go 10W-40 when the ambient temp gets to about 100 or closer to 110 degrees and im driving the car. and why or why not. Thanks

Got right about 163,000 miles on here, 163736 last time i looked, it has 5 digits so its either 63000 (unlikely,) or 163,000 or 263,000 miles. Runs strong, this engine here. no more smoke on startup either so something is doing something, maybe it just needed to be ran. Ii also put healthy dose of MMO in the gas, way more than im supposed to. yielding good results. sat for months now its an every other gay grocery getter, the idling makes up for my short trips, its still HOT out here tough and yes i let it run a half hour or more every time.. sludge already IN engine, too. still runs strong. what to do ?


just run rotella 15w40 and change the oil once a year. you cant bring it back so y bother? just drive it until it quits

 

[CATERHAM]

Originally Posted By: SuperFast
Originally Posted By: CATERHAM

Why not just use 10W30 ? coulda swor it specd 10W30 not 5W30

Of course you could use a 10w30 dino, particularly in a warm climate (a 10w30 syn is a waste of money) but 5w30's, even dino's are so good to render the 10w30 grade largely obsolete.

 

[SuperFast]

Thanks, all. ill not add any more MMO or STP, though the MMO may have been helping and ill keep an eye on what comes out. ill use a 10w30 or 10W-40 tis 10W30 is working very very well, but mechtech does [oint out it has the STP counteracting the old oil and mmo, on new filter..

ill leave all out except a dab of RL break in oil for zddp and keep it hi-mi dino 10W30 OR 10W-40.

what will happen if i mix 2 quarts 10W30 and 2 quarts 10W40, and flip a coin as to quart 5? and shall i discontinie MMO use in this engie, particularly if it runs very strong and i put a LOT of mmo in the gas ? (it stays half full or more now, mmo is helping and i want to use more gas cleaners as it sat a few months and ethanol fuels DO go bad)

to recap, i changed the filter not oil, added 16oz mmo and a small bottle STP and im changing the oil in about a month or two or three, with dino hi-mi oil. debating 10w30 which is working very well on this fill or 10w-40, and also mmo or not. engine rins very strong and is sludged badly is why i ask.