Finn5033

I am swapping engines in my 70 cutlass due to a worn out motor. I used the numbers from the engine above the water pump and figured out the engine that was in it was a 72. Does anyone know if the 72 would have had an egr valve? I am wondering because the Intake on the motor does not have a spot for an egr valve. The engine I am dropping in is a 77. I was going use use the q-jet off the motor that was in the car, then I got to thinking maybe I could just swap the entire intake as it would save me a lot of time. If the intake is from 72 would it bolt onto a 77 block? Second question is do you need to tune the engine differently if switching from single to dual exhaust? any thoughts or advice would be appreciated. Thanks

frankr442

No EGR on a 72 (started in 73). I think the manifold will bolt up, but maybe the port sizes could be different because they list different gaskets for 72 and 77. I would try it if only to keep it original looking. Change the base gasket on the carb while you're there. I wouldn't mess with the adjustments until you run it for a while, maybe keep an eye on the plugs. Although it could probably use a rebuild if its a virgin.

Finn5033

The reason I was wondering if I could just swap the intakes is I was going to re-use everything off the motor that came with the car so I would save money and it would save time. I didn't want to mess with the carb either. I would need a new erg valve which is over $100 too. If it bolts up but the ports are different size what kind of problems would I be looking at?

MDchanic

As far as I know, the ports are the same. To be honest, I've just thrown the EGR manifolds on the pile and never looked at the ports (okay, a pile of two, but it's still a pile).

For a low compression '77 motor, I wouldn't worry about it anyway - performance is not a 1977 hallmark.

- Eric

Finn5033

I am still learning but I assume what your saying is I should be able to put the intake from the 72 onto my 77 and it will work just fine? That would be great, as I didn't want to deal with the EGR valve. I am looking to save time and money here as I want to put that effort into rebuilding the original numbers matching engine I got with the car.

frankr442

You could just put a block-off plate over the EGR hole. Watch to see if it pings when hot, you may have to go back to the EGR system.

MDchanic

A block-off plate is fine, but of course if he already has an earlier manifold and is planning to pull the manifold anyway, it's cheaper and easier to just use the old one.

As for EGR mixture issues, using the non-EGR carb should eliminate that problem.

- Eric

frankr442

But since the 77 motor is complete, the cheapest and easiest thing to do is use a block-off or even just ignore the EGR valve, as long as it's not stuck open. I think the only reason he was pulling the intake was to do away with the EGR.

Finn5033

I have already pulled the intake off of the 77 to replace the gasket. So I prefer what mdchanic is saying. I won't have to mess with pulling the carb or anything I can just swap the intakes and be ready to roll. The carb and intake are both 72

MDchanic

... And I believe that the compression ratios are the same for '72 and '77, so the carb should be calibrated well for the application (I believe that the cam was different, or was retarded a bit for '77, though, so that might be an area of improvement).

- Eric

Finn5033

Thanks for the help, I am glad to hear that this should work

joe_padavano

Two clarifications. First, EGR was a mid-year addition on some California cars. Second, the block casting number above the water pump will NOT tell you the year of the motor. Despite what the FAQ may say, Olds used the same casting number on all 1968-1976 350 blocks.

Finn5033

ya I understand that, I used the numbers off of the intake and the carb too and everything pointed to a 72. My main question was if I could use a non EGR intake on the 77 engine.

Finn5033

I may be getting off the topic here and maybe I should start a new thread. I was reading up about the difference in the engines from 68-72 and 73-76 and 77 and up. I saw some info regarding the heads. Would it be worth it for me to check out the heads on the 72 motor and possibly put them on the 77? Would it make any kind of difference for me?

olds 307 and 403

Use the carb, heads and intake on the 77 block from the 72 motor. Also use either the Corteco .028" or .011" gaskets. The thicker Fel Pro gaskets will loose compression and quench.

MDchanic

Didn't you just ask this question on a different thread?

Running the same question on multiple threads is a recipe for confusion for everyone involved.

- Eric

Finn5033

yes I asked it here first but got no responses so I started a new thread since it was a different topic