307 upgrades
- Thread starter Dripz1985
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Just drive it and be happy with it the way it is.
There's no bolt-on that you can really do to a 307 that will make it anymore fun without seriously affecting the reliability and longevity of the engine (aka nitrous, etc.)
Yes you could install headers, dual exhaust, aftermarket intake, etc. that could be used later on down the road on a 350 or 403 but in the interim, it's not really going to do much for the 307.
Your only other option, short of putting in a bigger engine, would be to rebuild the 307 and do all the typical performance upgrades at that time (cam, pistons, heads, intake). But then you're dumping a bunch of money into something that will only really get you close to the performance of a mild 350.
Save your money for a 350/403 or 425/455 later on down the road.
There's no bolt-on that you can really do to a 307 that will make it anymore fun without seriously affecting the reliability and longevity of the engine (aka nitrous, etc.)
Yes you could install headers, dual exhaust, aftermarket intake, etc. that could be used later on down the road on a 350 or 403 but in the interim, it's not really going to do much for the 307.
Your only other option, short of putting in a bigger engine, would be to rebuild the 307 and do all the typical performance upgrades at that time (cam, pistons, heads, intake). But then you're dumping a bunch of money into something that will only really get you close to the performance of a mild 350.
Save your money for a 350/403 or 425/455 later on down the road.
That sounds like a carb rebuild problem. Since you have a '85, That 307 is likely to be the smog motor. Meaning that it has the worst flowing parts of all the 307s, but has a hydraulic roller cam. One year down ('84) and It could of had some potential. What you should do is what FE3X Clone said, That motor needs to run as close to STOCK as possible. Depending on the miles, a new timing chain, clean up and rebuild the carb, and a tune up will do wonders. you may even be able to spin your tire after those changes. (Odds are against it, bad gearing.)
But first lets be sure that you have the smog motor. Very simple check to do. Look at the intake manifold on the pass side between the front of the carb and behind the thermostat housing. The bottom is usually very dirty, so you'll have to clean that area. You are looking for the marking A5 or A4.
A5 means it's the smog motor. A4 means it's the early 307. The early 307 will wake up with a mild cam, headers, and a good flowing exhaust. ( But don't expect miracles, It is only a 5.0 motor in a heavy car.) Those changes will make it more efficient.
The smog motor was designed to be efficient from the factory. Torque is that motor's specialty. From idle to about 4000 rpm and thats it. The best example of this motor isn't even in a Olds. It's in the 85- 90 Cadillacs. The early 307 can spin up to 5800 rpm with the changes i mentioned.
T
But first lets be sure that you have the smog motor. Very simple check to do. Look at the intake manifold on the pass side between the front of the carb and behind the thermostat housing. The bottom is usually very dirty, so you'll have to clean that area. You are looking for the marking A5 or A4.
A5 means it's the smog motor. A4 means it's the early 307. The early 307 will wake up with a mild cam, headers, and a good flowing exhaust. ( But don't expect miracles, It is only a 5.0 motor in a heavy car.) Those changes will make it more efficient.
The smog motor was designed to be efficient from the factory. Torque is that motor's specialty. From idle to about 4000 rpm and thats it. The best example of this motor isn't even in a Olds. It's in the 85- 90 Cadillacs. The early 307 can spin up to 5800 rpm with the changes i mentioned.
T
Jetsetw31, I think it would be more accurate to replace the words 'smog motor' with 'swirl port motor' or 'rollor motor' because both kinds of 307's were 'smog motors'!
Dripz1985, don't waste your time trying to make any significant improvements on your 307 with bolt-ons. They aren't going to get you what you're looking for. You need to tune what you have because you shouldn't have to pump the gas forever to get your engine to start.
If you have some money to spend, get better gears. Do that and you'll notice a difference but it still won't be fast. I had a low milage early 307 ( the low performance version, not the hopped up 442/Hurst Olds version ) in my car temporaraly last year. Even with my 3.73 gears, 2300ish stall, headers, cowl induction scoop, small carb spacer and dual exhause with X pipe, it wasn't even close to being fast. If you had a setup like that, you wouldn't be happy. Since you have the later 307 with swirlport heads and dinky intake, your performance would probably be even worse than what mine was.
Tune what you have and get it running correctly first and save your money for a better engine. When you're ready to spend some money, I say start with the gears.
Dripz1985, don't waste your time trying to make any significant improvements on your 307 with bolt-ons. They aren't going to get you what you're looking for. You need to tune what you have because you shouldn't have to pump the gas forever to get your engine to start.
If you have some money to spend, get better gears. Do that and you'll notice a difference but it still won't be fast. I had a low milage early 307 ( the low performance version, not the hopped up 442/Hurst Olds version ) in my car temporaraly last year. Even with my 3.73 gears, 2300ish stall, headers, cowl induction scoop, small carb spacer and dual exhause with X pipe, it wasn't even close to being fast. If you had a setup like that, you wouldn't be happy. Since you have the later 307 with swirlport heads and dinky intake, your performance would probably be even worse than what mine was.
Tune what you have and get it running correctly first and save your money for a better engine. When you're ready to spend some money, I say start with the gears.
Easiest way to get more out of that 307 is to Chip it if youre still running the stock ECM
here is a coomparison I did where the chip was a drastic improvement to a mostly stock system:
viewtopic.php?f=10&t=41141
Get a hypertech chip .
PS if youve got 2.XX gears they can really make the car feel like a dog. 3.XX gears are the next thing I would consider, but are more involved.
here is a coomparison I did where the chip was a drastic improvement to a mostly stock system:
viewtopic.php?f=10&t=41141
Get a hypertech chip .
PS if youve got 2.XX gears they can really make the car feel like a dog. 3.XX gears are the next thing I would consider, but are more involved.
Even with the roller motor, I imagine a true dual exhaust system would help.
Heck, I noticed seat-of-the-pants improvements opening up the exhaust on the 231 V6. Nothing to impress anyone, but it was noticeable. If the little V6 was choked by that single exhaust system, I imagine the 307 is struggling even more with it.
Heck, I noticed seat-of-the-pants improvements opening up the exhaust on the 231 V6. Nothing to impress anyone, but it was noticeable. If the little V6 was choked by that single exhaust system, I imagine the 307 is struggling even more with it.
True, But honestly damn near everything in the 80s was a smog motor. LOL.DoubleV said:
The general point here is to stay conservative with your car. Save up and upgrade to the better engines that go into these cars. You'll love the difference.
T
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