Olds 350 Question List

[dan2286]

So will my sensors from the 307 screw into the 350 so I can use the 307 harness?

You'll probably want to get an A4 manifold off an earlier 307 (non-roller engine) to use on the 350. That will make the swap much less problematic if your trying to keep the computer.

Personally, if you don't have to deal with emissions or inspections, just unhook the wiring harness and tuck it up along side the passenger fender. Then get a '74-'79 Q-jet and HEI as mentioned above. Bolt on and go.

The other issue with keeping the computer is your going to need a place for the O2 sensor. You won't be using the exhaust manifolds from the 307 so you'll need to have the 350 manifolds modified (drill/tap or weld bung) for the O2 sensor.

Oh ok. I really would rather go without the computer so the engine compartment will look cleaner and less clutter. But the only thing that has me intimidated is the thing about the trans lock up.

As long as you have decent mechanical skills and are okay with electrical, kits are not very hard to hook up. I believe the best kits come with a pressure switch and a vacuum switch to keep the torque converter from locking up under part throttle. It looks like painless makes one of those style kits, but not sure on the price.

 

[FE3X CLONE]

I've found the vacuum switches to be pieces of junk. They never lockup when they are supposed to.

The B&M kit isn't perfect either as I don't believe it would unlock when you stepped on the brake pedal until you went below the set lockup speed.

 

[J.Rod22]

What would happen if I was to drive it without the lockup

 

[megaladon6]

Not all 80s carbs are ccc, the first few years and many canadian models are not. Plus the trucks.
and why have to get ANOTHER item like the aftermarket cable or corrector kit?

 

[FE3X CLONE]

Not all 80s carbs are ccc, the first few years and many canadian models are not. Plus the trucks.
and why have to get ANOTHER item like the aftermarket cable or corrector kit?

True but then he's going to have to rig his fuel line to put a Chevy carb on it. And it's not like an aftermarket cable is a huge deal breaker.

What vehicles in the '80's used a TH-2004R or TH-700R4 that weren't computer controlled? I know all Olds engines with a TH-200 or TH-2004R would have had an electronic carb.

 

[J.Rod22]

What's the difference between a 70 olds 350 with the 2barrel carb. Vs the one with the 4 barrel carb. Are the two engines different or is it just a different carb?

 

[DoubleV]

The 4 barrel version had a higher compression ratio. Advertise CR was 10.25 to 1 ( I think ) and the 2 barrel were 9 to 1. In reality, these CR were lower.

 

[J.Rod22]

The 4 barrel version had a higher compression ratio. Advertise CR was 10.25 to 1 ( I think ) and the 2 barrel were 9 to 1. In reality, these CR were lower.

Ok but I could swap the intake on the 2bbl to a edelbrock performer intake and use a 4bbl carb right?

 

[DoubleV]

The 4 barrel version had a higher compression ratio. Advertise CR was 10.25 to 1 ( I think ) and the 2 barrel were 9 to 1. In reality, these CR were lower.

Ok but I could swap the intake on the 2bbl to a edelbrock performer intake and use a 4bbl carb right?

Sure can.

 

[joe_padavano]

What vehicles in the '80's used a TH-2004R or TH-700R4 that weren't computer controlled? I know all Olds engines with a TH-200 or TH-2004R would have had an electronic carb.

Canadian cars with the non-computer carbs used a vacuum switch and trans pressure switches to lock and unlock the converter. Same thing for the early 80s trucks.

Diesels used the 200-4R. There was no computer. The lockup was also controlled by a combination of trans pressure switches and a vacuum signal that was produced by a vacuum modulator switch on the diesel injector pump. Since diesel engines don't have manifold vacuum, a vacuum pump was used as a source, and this proportional vacuum modulator valve on the injector pump created a vacuum signal that was proportional to throttle position and essentially mimicked the manifold vacuum signal of a gas engine. This vacuum signal was used to control the modulator on the TH350 and was also used to work a vacuum switch for converter lockup on the 200-4R.