I have newly rebuilt 350 bored 60 over and it is overheating I think it is the timing but I'm not sure, what should I set the timing at, it also has no power at all, is there a reason for that ,everyone tells me it should be fast but I can't even spin a tire. I also just upgraded to bigger jets and smaller metering rods but it did nothing. the tune is set at 14 afr at idel , its a newly rebuilt 350 bored 60 over brand new aluminum 4 core radiator with 2 electric 16 inch fans and a shroud that was made for the fans. Thank you for your time and thank you for any responses
Overheating 😫77 nova
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I am not an expert...however, since it's a new build, you might want to check if your rocker arms were properly adjusted. If I recall correctly, back each nut off until the rocker arm/valve starts tapping, then tighten slowly just until it stops tapping, and then, I think (not sure) tighten it one full turn. I believe one full turn sets the push rod in to the right location in the lifter. If I'm wrong, someone please correct me and provide correct information. I know if not properly adjusted, the motor just runs like crap...no power and sluggish...
Let us know what happens and what the solution ends up being.
Let us know what happens and what the solution ends up being.
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It may, and it may also result in valves not closing fully. 1/2 turn is usually the "rule of thumb", that will get most most stock or mild build motors in the ball park.
Timing - this depends a LOT on the specific build of the motor. If I set my 489ci BBC to stock BBC specs, it's gonna run like garbage. Largely due to the cam, it needs considerably more initial timing, and less advance than a stock motor If you set a stock 350 initial timing to match mine, you're probably going to hurt the motor. If yours is a factory stock or mild rebuild, I'd set it at 8* BTDC for now, and play with it a bit later once you get it running decently. You can probably get away with a bit more, but 8* is a safe middle ground. Make sure you're running the vacuum advance off of manifold vacuum, and not ported vacuum.
Changing jets is a not an "upgrade", nor is going bigger necessarily going to give you more power. It can very easily send your power right off the proverbial cliff by going too rich. It's part of the tuning process. Some combos are going to want smaller jets, some will want bigger.
TWO 16" fans? How?!?!? Do you have one on each side of the radiator - as in one front and one back? I can't imagine fitting a pair of 16s on the same side of a Nova radiator. It would be tight getting a pair of 16s on the back side of the radiator in my F350, and that thing dwarfs a Nova radiator.
If you DO have fans on both sides - THAT is a big part of your problem right there. You're going to have fans fighting each other, even if the front one is a pusher and the engine side a puller, and you'll end up with lousy air flow through the radiator even at freeway speeds. If they're cheap no name Amazon/Ebay fans, that's a problem too. They virtually never come even remotely close to the CFMs that the sellers claim they pull, and a single 10" Spal will often pull significantly more air than even a pair of 16" imports will. BTDT, have the over heated motors to prove it.
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Have you checked to see whether your thermostat is functioning properly (do you even have a thermostat?!?)? Or if you even have one? As @Suicidal_Therapy mentioned as well, fans and the relay are a big part of cooling properly and need to be paired accordingly. If your AFR is set at 14, you're lean as F! Where in the rpm range are you taking this reading? Here's one guy's issue with lots of good advice to fix (it sounds like you have an Edelbrock carb but AFR is AFR):
AFR Tuning: A Holley Carburetor Journey
Hey all, I'm making good headway on my 1965 Olds F85 with a 496 BBC. I have this car relatively mechanically sorted, and bought this AFR gauge as...
www.v8buick.com
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Tuning with Air Fuel Gauge - Edelbrock Community Forum
Heyall, I am really hoping to get some advice on tuning up my car. It's a custom car running a 1991 Ford 302 HO with an Edelbrock 1405 carb. The engine has mild performance mods, including performance heads and cam, intake and exhaust. I drove the car for the first time last year and it drove...
forums.edelbrock.com
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my second car was a 74 SS Hatchback. wrecked a few times. different colors all over, but fast as hell. I put Mustang Seats and a Pinto Shifter in that thing..... LMAO
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Welcome/ Hope all this information helps you out.
Welcome to the site! One member comes to mind [email protected] Need more information I think though. It seems you have 2 pressing issues...low on power and overheating.
What is your calculated or actual compression ratio?
What cam? Flat tappet or roller?
What heads?
What carb?
What ignition?
What is your initial timing and total advance?
Good oil pressure?
What fuel?
Cam break-in (if flat tappet) done correctly?
Cam timing verified/set when engine assembled?
Any smoke coming out of the exhaust? If so what color?
Simple cooling system check to verify thermostat/pump operation:
1. Take the radiator cap off with engine cold.
2. Make sure full of coolant.
3. start the engine and let it come up to temperature while idling.
4. watch the coolant through the rad cap opening while checking the temp gauge.
5. You should be able to see when the thermostat opens by coolant circulation.
6. put the cap back on and shut down the engine before it gets too hot.
When you say its overheating, can you be more specific? Temp gauge goes too high and you shut it down safely or...?
What is your calculated or actual compression ratio?
What cam? Flat tappet or roller?
What heads?
What carb?
What ignition?
What is your initial timing and total advance?
Good oil pressure?
What fuel?
Cam break-in (if flat tappet) done correctly?
Cam timing verified/set when engine assembled?
Any smoke coming out of the exhaust? If so what color?
Simple cooling system check to verify thermostat/pump operation:
1. Take the radiator cap off with engine cold.
2. Make sure full of coolant.
3. start the engine and let it come up to temperature while idling.
4. watch the coolant through the rad cap opening while checking the temp gauge.
5. You should be able to see when the thermostat opens by coolant circulation.
6. put the cap back on and shut down the engine before it gets too hot.
When you say its overheating, can you be more specific? Temp gauge goes too high and you shut it down safely or...?
Its a pretty big radiator so both fans are on the same side pulling the air towards the engine, it overheats when its at about 3 to 4 thousand rpm in park. ( make sure you're running the vacuum advance off of manifold vacuum, and not ported vacuum.)can you elaborate a little on this I am a little new to this stuff.
In park when it is revved up to at least 3 to 4 thousand rpms thanks for your response I hope so to
Ok so I'm not sure what compression I'm running I haven't really checked because it was just rebuilt
Its a mild cam flat tappets I used the old ones off of my other 350 ,not new ones that could be the problem
Stock heads
Not sure what ignition
Timing is at 11 or 12 I think like I said before I'm a little new idk what total advance is
I don't have an oil pressure gauge
87 fuel type
It was old tappets but yes it was broken in right
And yes the dots were aligned when being built
And I don't think there is any smoke but when it was first started it had blue smoke
And ya I've tried that for the over heating and it gets to about 230 when at 3 to 4 thousand rpm
Thanks for the welcoming
Thanks a lot guys you are helping a lot THANK YOU
Me and my bro tried that already, thanks for your response and I definitely will
I'm hoping so to broThank you guys
And its a 1406 eadlbroc carb
I will try that man. Ya I bet that thing was FAST did you ever run it on a dino ??
If 14 air flow ratio is lean what should I set it at . thanks again for your responseHave you checked to see whether your thermostat is functioning properly (do you even have a thermostat?!?)? Or if you even have one? As @Suicidal_Therapy mentioned as well, fans and the relay are a big part of cooling properly and need to be paired accordingly. If your AFR is set at 14, you're lean as F! Where in the rpm range are you taking this reading? Here's one guy's issue with lots of good advice to fix (it sounds like you have an Edelbrock carb but AFR is AFR):
AFR Tuning: A Holley Carburetor Journey
Hey all, I'm making good headway on my 1965 Olds F85 with a 496 BBC. I have this car relatively mechanically sorted, and bought this AFR gauge as...
Ya its a 1406 edelbrock
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Hey there. The AFR is dependent on the RPM range and load you are applying to the engine. If you have your AFR set at 14 on acceleration, you will kill your engine immediately due to a lean condition. Honestly, the best method for tuning is using your AFR gauge and reading your plugs. While the higher ethanol content in today's gasoline can cause some confusion on reading your plugs, you can absolutely rule out a overly-lean condition by seeing some color on the ceramic insulator in the plug and on the electrodes. I typically get the motor close with a bit of fuel smell from the tailpipe then start from there knowing I am not going to kill it due to an overly-rich condition then, I will jet down from there until I get the color I want on the plugs and see the motor running its best. The Edelbrocks are really quite tuneable with just metering rods and springs coupled with the accelerator pump shot rod location (go mid hold and work from there). You may not have to jet up or down but you really need to establish where in the RPM range you are taking your readings. Here's a link to the tuning guide:
I'm certain others here can help you out as well.
Check this out here at SNS (Thanks, @RifRaf ): Carb Tuning with Wideband AFR Gauge?
Good luck and let us know how things go.
Very welcome. I wasn't trying to overwhelm you with the questions. It sounds like someone else rebuilt the engine for you? Old cam & lifters is uncommon (I think) but possible if they were all in good shape and the lifters went back into their original bores I suppose. But if it's an OEM cam...that could contribute to your power over-expectations I think. The other thing to be aware of is the transmission and rear gearing are important to the engine power characteristics. You want the power curve of the engine to match up with the converter of an auto transmission. Higher numerical rear gearing will give you more acceleration but a slower top speed. Lower numerically and you will get a higher top speed and less acceleration. For a Nova, a rebuilt 350 bored 60 over and an automatic transmission with rear gearing above 3:20 (all working properly), I would expect tire smoke festivals to be very easy!
Wait a min...did the entire engine go back together with all the smog/emissions equipment? Factory exhaust manifolds, factory intake manifolds, emissions air pump?
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