Olds 307 to Olds 403 engine swap info please?

Mike that GP is wicked sexy! The tree fiddy is looking awesome bro, damn thats hot!

My 87 was like this one in color, minus the nasty white walls and mine didn't have vinyl top. Also had American Racing Hurricane 2 wheels.




I also had a 79 GP with Fresh paint and a blown 301 for $300, I found a rusted out 70 skylark with a Buick 350, that rotted away when the old lady went blind, it had 70k-ish miles on it for $200. I ran the stock Pontiac Rally wheels with 245/60/14's on the rear and 205/70s on the front. Not many people liked the color combo, but I loved it!

This was not mine, but looked just like this when I got it.

 

I remember that paint job on those late 70's Grand Prix's. Very groovy. Ha!

I loved that '85 GP, but always wished that it didn't have the vinyl top...I don't like those, and DID wish it had t-tops or a sunroof. It was a great car, Texas from new so zero rust. One odd thing, it was only a 3spd, it did not have Overdrive. Odd considering how loaded it was.

I miss it. Never should have sold it...but I'm sure we can all say that about a few past cars!!

-Mike

 

Couple of update pics from the shop. Have not been able to get down there much lately, but 307 is about ready to come out. Still will have to paint then engine bay, and then will drop the 350 in.





-Mike

 

Ok the guilt trip from others about the black paint is wearing me down.

I've been talking to Olds folks and am told VHT #sp-132 Universal Gold works well. Not perfectly correct, but less metallic than the Dupli-Color gold AutoZone sells.

About $8 a can. What do you think? Do I need to pull the intake and valve covers off and re-paint the block....?

Nothing like pressure from friends....


Here's the only two pics I can find of it on someone's cars



This is what I had purchased at Autozone...it looked VERY wrong!


-Mike

 

It will look like a stock 307 in black, like it's supposed to look, and be a fun sleeper. I'm sure I will be out voted.

 

Tough call, I don't think I've seen enough different engines to voice an opinion. I've just always associated gold blocks with Olds though. Blackmight be a good color too.

 

I would go black for the stealth factor too. No one will expect a stock appearing 307 to be anything but. I would do the same for a '65 Chevy wagon. The original 283 would have been Chevy orange. The massaged and muscled 6.0L truck LS motor that goes in its place will be just that, with a plain appearing HEI distributor, carbureted manifold, stock air cleaner, and relocated coils and whatnot. Same goes for a 500cid Caddy engine stuffed in a '75 Cutlass Cruiser. It'll be light metallic blue like a stock 260 or 350 would have been. I'd even put dark Ford blue on a late model EFI 302 just to put one in my Torino if I ever kill the 351C. But I'd have to change it to TBI so it could run a regular round air cleaner. Those 302 EFI intakes are hideous.

 

Sorry for not updating!

The Cutlass is still in pieces. I could not find a dipstick tube for it, so ended up taking the oil pan off the old 307 and beating the tube out of it from the bottom. Man what a MESS, that 307 was NASTY inside. I kept the oil changed the year I had it, but the bottom of the pan was full of chunky sludge. It’s no wonder the car had no oil pressure if it was sucking that into the engine. Yuck.

I had to take the passenger side exhaust manifold off the 307 to get the dipstick tube out as well, the tube runs under it, between the manifold and the block. It’s amazing how small the 307 exhaust ports are, they are round, and about the size of a quarter. It’s no wonder those engines are so weak, they can’t breathe! The ports on the 350 are HUGE in comparison.

Also had a little issue with belt alignment. The 350 harmonic balancer is just a tad wider than the 307, so I have to put one washer on each of the water pump studs to align the upper and lower pulleys.

The current issue is sorting out the vacuum stuff. I’m not running a smog pump on the 307, and have removed all the emissions-related garbage, but still have the EGR, have to make the carb and cruise control work.
The carb, distributor, and overdrive in the transmission are all controlled by the computer….and I don’t know how the computer is going to react to the having the majority of the emissions devices removed. I really hope the car runs and shifts!

I’m thinking if it doesn’t run, or runs terrible, I may have to get an aftermarket carb, a pre-1980 vacuum distributor, and an aftermarket switching device for the overdrive, and just totally take the stock computer out of the mix. I guess we’ll see soon enough! Getting close to turning the key!

It is cool to finally SEE the engine in the car! Will keep you folks updated.

-Mike

 

I believe the only thing the computer controls on the transmission is the converter lock/unlock. It will still shift into overdrive, but the converter may not lock. My dad has the B&M lock up kit on his '86 El Camino and it works well. I'd honestly just switch to a vacuum advance distributor anyway. Who knows what the timing curve looks like for the smogged 307. I cannot recall what is controlled on the carb, but it can't be much.

 

I figured I could just swap all the 307 electrics over and it would run fine for now. We'll see how it acts. Almost there!

 

Ok spent the weekend at the shop and running all over town for parts. Here's the novel!

- The 350 in the Cutlass is finally RUNNING!!

BUT.....

SATURDAY:

Here's the deal, got everything finally all hooked up Saturday. The pretty '71 Olds 350 that I spent so much time painting and detailing was now buried under an ugly (but supposedly rebuilt!) computer quadrajet carb and 10,000 vaccum lines. It looked for all the world just like the 307...with some chrome valve covers added....yuck. The smog pump and related hoses are gone, but I put all the sensors, vaccum hoses, and connections off the 307 back on the 350. It's was not pretty.



I primed the carb, turned the key, and the new 350 engine fired right up! That was a cool moment. Then it stalled. It would start, but not idle.
After messing with it for an hour, tracing vaccum lines, looking for vaccum leaks, staring at the Check Engine Light glowing on the dash, wiggling sensors and trying to adjust the carb and the timing to make it run right, I was about to scream or cry or something.

I ended up adjusting the idle to 1300 rpm, where the engine ran smooth, and took it around the block.

The GOOD is that the engine has no knocks, taps, and does not smoke, and has TONS more power than the 307. The exhaust does not leak and the engine didn't drip and fluids. All that is good.

The BAD is that below 1300 rpm, the engine is shaking around, and below 1100 it stalls.

Dang.

Time for PLAN B! The computer is going BYE-BYE!!



I went and bought the brand new 600cfm electric choke Edelbrock above. It's a thing of beauty, I tell you it's pretty....and it wiped out pretty much all that was left of my paycheck too, but dammit, I want this car to RUN RIGHT!!

Spent the rest of Saturday afternoon taking stuff off the top of the engine, and cursing myself for doing all that work trying to keep it stock.
My current plan is to retain the vaccum for the heater valve, retain the cruise control wiring and vaccum, keep the temp sensors for the dash gauge and light, keep the air conditioning wiring, and pardon the term, but to ****can the rest of the hoses, sensors, and associated garbage that's hiding my pretty new engine.

So I got to work.

Once I got all the garbage off the top the engine I set out to look for parts. I needed two shorter bolts to install the Elelbrock carb on the intake (the new engine already had an Edelbrock Performer 350 intake on it, so this is a good match of carb and intake I hope!), needed to cut the metal fuel line and replace it with a rubber line and an inline fuel filter.
On setting the carb on the intake, I realized the EGR valve is going to be in the way of the rod for the cruise control. I thought about it a minute....do I really need an EGR valve? The engine is a '71 model, it didn't have one new. SO off came the EGR valve, but NONE of the local parts stores had a block-off plate for it. I went to them all, but it was almost 8pm now. Finally at O'Reilly the guy said he found a chrome Mr. Gasket plate at a South Austin store, but it would be closed by the time I got there.

So I went back to the shop, closed up, and went home and showered for about an hour.

Saturday night I re-read this thread for tips from you guys, as well as going over to the G-body forum and going through 307-to-350 swaps there. I realized that I'd forgotten in my frustration over how it ran and my buying the new carb that the advance and retard on the 307's distributor was controlled by the computer. I would need a pre-1980 Olds vaccum distributor to go with the Edelbrock carb. The bad part was I was now pretty much broke. I looked online and the lowest price I could find for a new disributor locally was $104 from AutoZone. Ouch. I did find out that the new cap and rotor I'd put on the 307's distributor were the same parts numbers as the pre-80 models called for, so at least I could use those again.

SO today I got up early and headed for Wrench-A-Part in search of a used distributor. Took some pics of cars there and will post them in the photos section for you guys. http://www.stationwagonforums.com/forums/showthread.php?p=191024#post191024

In the far left corner of the yard I found this 1978 Buick wagon, with a 403 under the hood:



The car was up so high I could not even reach the distributor, so I stacked up some wheels and pulled the VERY GREEN vinyl lower seat cushion from the 2nd row, and layed it in the engine bay, then climbed up and layed across the engine on the seat, and after a lot of sweating and cursing, nabbed this for $30! Woo-hoo!




Next I hiked out of the yard, which in the direct sun on the white rocks had to be about 110-degrees, got into my pickup, which was about 125-degrees inside after sitting in the dusty parking lot, and got on the highway back toward town with the a/c cranking.

I got to the O-Reilly Parts Store in South Austin and $10 later had a new chrome EGR block-off in my hand. The counter guy asked what I was going to use that on. He said according to the computer that part had been in the store since 1996! Wow! I told him about the Cutlass and he said he'd love to see it, and then I got back in the truck and headed for home.

Off the subject, but they are raising the speed limits all over the state and workers were out this weekend. For someone that grew up under the Federal 55, seeing these new signs is pretty awesome. Could not resisit nabbing the pic below:



God Bless Texas!

I got home and Misty made it clear that, after showering, I needed to spend some time with her and the kiddos, so that's as far as I got this weekend. Went to my parents house and we all went swimming, which with my sunburn from the salvage yard, felt like heaven! Then my wife took us to dinner. Nice.

Now I'm just settling down and figured I'd share the weekend work with ya'll. I'll get back over to the shop after work a few nights this week I hope. I'm still concerned about the a/c and cruise working now that the computer is out of the loop, and also if I'm going to have to modify the transmission since the overdrive and lock-up converter are computer controlled. Will have to read into all that.

For now, the immediate goal is to get the car really running well, and get it back home so I can clean and detail under the hood and then I'll start sorting out the questions above. As long as I can get it running, I believe I can drive it the 12 miles home from the shop in drive/3rd, not overdrive, and not hurt the transmission.

That's all for now gang!

-Mike

 

Thanks for the update Mike, good luck sorting out that engine. The 80 mph speed limit sign looks really bizarre to me being from Ga. Your new 350 engined Cutlass should be right at home with it though. for rating in engine changeover category.

 

Yep I hope the Olds will do 80 now. With the old 307 that was about top-end.

-Mike

 

Well shoot, in looking around the Edlebrock 1406 will not bolt on the Performer 350 EGR Edelbrock manifold that my rebuilt 350 came with. The shift linkage will hit the EGR boss. It looks like I'll need a 1-1/4 inch spacer to make it work.

Ah the joys of mixing and matching aftermarket parts.

I hope the hood will close over the air cleaner once I do this. Will head to the parts store and lunch and see if I can find a spacer to make this work. Such fun.

-Mike

 

Ran over to the local speed shop, Austin Performance, just now. Told them the issue with the carb, and the guy smiled and handed me this:



VERY COOL! It's made specifically to adapt an aftermarket carb to a Quadrajet intake. Even includes studs, nuts, and gaskets. $25, hard to argue with that!!
I dropped it off at the shop, and found the NEXT issue. The EGR blockoff plate that I bought does not fit. It's too small.

I went back to Austin Performance and was told that Edelbrock does include an EGR blockoff plate with their new manifolds, but does not sell them outright. Dang! He said most people have them made or make them themselves, BUT he gave me the number of a shop that might have some laying around. I called and the guy is looking and said he'd call me back.

Ok then. Back to work.

-Mike