- Mar 25, 2020
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I got a stock 425 in a 67 delta88 what kind of carb and intake should I run... any tips on this motor
(67) 425 olds
- Thread starter Moreno_831
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Olds 307 and 403
Well-known member
I say a Performer BBO intake with the stock 750 CFM Qjet rebuilt. Or a custom tuned 76 to 79 800 CFM Qjet or a 750 Street Demon.
Okay, let me go down the rabbit hole on this one. In my opinion, assuming you're Quadrajet 4-barrel is in good shape and the engine is properly tuned, good points, rotator, cap, wires, spark plugs. Baseline A. Changing to an Edelbrock Performer and take your pick of carburetors, horsepower gain= zero to one horsepower. 
Why? The factory Quadrajet and factory 4-barrel can deliver more CFM than the engine is able to take. Why is that, one may ask. These cars are "difficult" to upgrade the "weakest link", the exhaust. Best case "factory exhaust" was the RARE factory S-drivers side manifold. I'll put a link to Thornton's. These manifolds were VERY RARE from factory, basically 1965/66 Starfire only. Thornton reproduces it now. Next, using this manifold, you'd have to modify your transmission shifter linkage, not a big deal, for some. Before Thornton started making the S-manifold, I'd cut, rotate, weld the Toronado driver's side manifold to get away of the "rear steer" steering box that makes putting tube headers on these cars, WITHOUT major modification. That is the main reason the Edelbrock performer will NOT give you any performance, imo. Next problem, factory gears. I scrapped out 20+ of these cars in the 1990s. I found two 3:08 posi's, most have one wheel 2.78 ratio. "IF" you want to spend money (after factory tuning/rebuilding Quadrajet and engine) put your money into the exhaust with Thortons manifolds. I'm just trying to save you money and point you in the right direction.
Exhaust of my Turquoise 98. That is what one week of work looks like.
Why? The factory Quadrajet and factory 4-barrel can deliver more CFM than the engine is able to take. Why is that, one may ask. These cars are "difficult" to upgrade the "weakest link", the exhaust. Best case "factory exhaust" was the RARE factory S-drivers side manifold. I'll put a link to Thornton's. These manifolds were VERY RARE from factory, basically 1965/66 Starfire only. Thornton reproduces it now. Next, using this manifold, you'd have to modify your transmission shifter linkage, not a big deal, for some. Before Thornton started making the S-manifold, I'd cut, rotate, weld the Toronado driver's side manifold to get away of the "rear steer" steering box that makes putting tube headers on these cars, WITHOUT major modification. That is the main reason the Edelbrock performer will NOT give you any performance, imo. Next problem, factory gears. I scrapped out 20+ of these cars in the 1990s. I found two 3:08 posi's, most have one wheel 2.78 ratio. "IF" you want to spend money (after factory tuning/rebuilding Quadrajet and engine) put your money into the exhaust with Thortons manifolds. I'm just trying to save you money and point you in the right direction.
Exhaust of my Turquoise 98. That is what one week of work looks like.
Olds 307 and 403
Well-known member
I agree, the performer, especially with a stock cam is a weight saver. Send your Qjet to someone like Everyday Performance, to do a proper rebuild or pay for a later 800 CFM core built to your specs. Your factory carb is 750 CFM, there will be more gained going to a tuned later carb than swapping intake manifolds. Are these the divorced choke carbs? Easy to convert the hot air choke carbs to electric. Dual exhaust with the above manifold is the best bang for your buck, hell even a 260 responds to dual exhaust. Between that and a proper carb rebuild will make it night and day better.
Last edited:
- Mar 25, 2020
- 23
- 4
- 3
Okay, let me go down the rabbit hole on this one. In my opinion, assuming you're Quadrajet 4-barrel is in good shape and the engine is properly tuned, good points, rotator, cap, wires, spark plugs. Baseline A. Changing to an Edelbrock Performer and take your pick of carburetors, horsepower gain= zero to one horsepower.
Why? The factory Quadrajet and factory 4-barrel can deliver more CFM than the engine is able to take. Why is that, one may ask. These cars are "difficult" to upgrade the "weakest link", the exhaust. Best case "factory exhaust" was the RARE factory S-drivers side manifold. I'll put a link to Thornton's. These manifolds were VERY RARE from factory, basically 1965/66 Starfire only. Thornton reproduces it now. Next, using this manifold, you'd have to modify your transmission shifter linkage, not a big deal, for some. Before Thornton started making the S-manifold, I'd cut, rotate, weld the Toronado driver's side manifold to get away of the "rear steer" steering box that makes putting tube headers on these cars, WITHOUT major modification. That is the main reason the Edelbrock performer will NOT give you any performance, imo. Next problem, factory gears. I scrapped out 20+ of these cars in the 1990s. I found two 3:08 posi's, most have one wheel 2.78 ratio. "IF" you want to spend money (after factory tuning/rebuilding Quadrajet and engine) put your money into the exhaust with Thortons manifolds. I'm just trying to save you money and point you in the right direction.
View attachment 951
Exhaust of my Turquoise 98. That is what one week of work looks like.
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- Mar 25, 2020
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- Mar 25, 2020
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Did you see my manifold? Is that the stock or should I change the ones I got? I’m not looking for horsepower just want a clean weekend cruiser.... but a posi rear end does sound good
- Mar 25, 2020
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I really just want to dress up the engine and get it running good. Car is leaving black puddles from my exhaust on my garage floor... also she’s choking when I get past 55mph
Attachments
That's the factory "S" dual exhaust, that's as good as it gets on those cars. The "rear" steering box is in the way for any kind of headers. The A-body (cutlass) is "front" steering box.
Olds 307 and 403
Well-known member
Get the carb sorted out and make sure the ignition gets a complete tune up with quality parts, points especially.
- Mar 25, 2020
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Thanks for the info you got some knowledge and experience I’m new to all this. For posi rear end 3:08 what do I need?
- Mar 25, 2020
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Yes this will be the first thing I do is sort out my carb issues... I’m debating on pulling the engine to fix all the oil leaks...
Even though I'm not on Facebook, I hear it's the "Hot" place to buy/sell auto parts/cars. I've been meaning to join but never have.
Craigslist is pretty much dead since they started charging to sell a car. They thought they were going to make some revenue but instead killed the golden goose. In the late 1990s/early 2000s I use to advertise in small weekly publications within a 100 miles. I probably bought 70/80 Oldsmobiles mostly. I have a car hauler.
I have hundreds of stories about buying/selling cars and parts. Here's one, I bought a 1975 Delta Royale convertible. Owners Daughter wanted the "eyesore" gone. I never met the "owner." He lived winters in Florida, came up in spring to Ohio. He'd given his house to the "mean" Daughter. The guy'd put near $2k into repairs to the car previous year. Anyway, the front seal let go. Car in garage. He went back to Florida. She had the car put outside (the kids always put the cars outside to deteriorate). She bitch's so he agrees to sell his beloved eyesore, from Florida. Long story short, nobody is buying non moving car that's rusted/top shot, yada yada. $400 later the cars on my truck "Big Daddy." One of the stories about this one car. The cranberry heavy vinyl interior was in good shape. It cleaned up very nice. I'd advertise it on Craigslist. A few people wanted a piece or two, usually there's always a hard to find piece that goes bad.
No, I'm selling all or nothing. A month goes by, a guy calls me from Nova Scotia. We talk, guy really NEEDS this interior. The car he has, missing most of the "cranberry" interior. My phone is dying, later.
Craigslist is pretty much dead since they started charging to sell a car. They thought they were going to make some revenue but instead killed the golden goose. In the late 1990s/early 2000s I use to advertise in small weekly publications within a 100 miles. I probably bought 70/80 Oldsmobiles mostly. I have a car hauler.
I have hundreds of stories about buying/selling cars and parts. Here's one, I bought a 1975 Delta Royale convertible. Owners Daughter wanted the "eyesore" gone. I never met the "owner." He lived winters in Florida, came up in spring to Ohio. He'd given his house to the "mean" Daughter. The guy'd put near $2k into repairs to the car previous year. Anyway, the front seal let go. Car in garage. He went back to Florida. She had the car put outside (the kids always put the cars outside to deteriorate). She bitch's so he agrees to sell his beloved eyesore, from Florida. Long story short, nobody is buying non moving car that's rusted/top shot, yada yada. $400 later the cars on my truck "Big Daddy." One of the stories about this one car. The cranberry heavy vinyl interior was in good shape. It cleaned up very nice. I'd advertise it on Craigslist. A few people wanted a piece or two, usually there's always a hard to find piece that goes bad.
No, I'm selling all or nothing. A month goes by, a guy calls me from Nova Scotia. We talk, guy really NEEDS this interior. The car he has, missing most of the "cranberry" interior. My phone is dying, later.
I'll try to shorten this up a bit. Guy "REALLY NEEDS" this interior, did I forget to say, THIS GUY REALLY NEEDS THIS INTERIOR!
(Now to the part why they call me "Mr Nice Guy") I say, how far are you from Niagara Falls? He says, 15 hours driving time. I'm 3 hours more beyond the Niagara Falls, in Ohio. I was selling the "WHOLE" interior for $700. Door panels, power seat, switches, yada yada. I tell him, I'll bring it to Niagara Falls, final price delivered for $500 U.S. Currency. SOLD! This was in February. He picks a place, McDonald's near the Falls, crappy area. 11 AM on the next Sunday. My Lady Friend, the 7 years younger, thin blonde but very smart, and I love Niagara Falls and go there once or twice a year. (I say if you find something that works, stay with it. I discovered the "POWER" that Niagara Falls has on women by accident the first time I took a girlfriend there. We went there for the day but ended up staying the night. We did see the Falls when we got there and when we drove over the bridge back into the U.S.A. This was 1969 and I've taken all my Lady Friends there since, with similar results. As TV'S Hunter use to say, "it works for me.")
Turns out to be an unusual sunny Sunday in the 40s. We left at 6am, arrived by 9am. Scoped out the McDonald's. Then we went to a little local diner named the "Y" restaurant, because the roads are a Y.
Good breakfast, friendly people, bs'd with another couple, killed some time. Went back to the McDonald's, guy and his buddy show up right on time. Bing bang, move the parts to his truck, pay me and 15 minutes later we're heading for a beautiful day at the Falls. The buyer told me, a Trim shop had quoted him 7K in Canadian money to do the interior. We had a great day, ate supper in Erie, PA on the way back. Win win for both of us. The 1975 Delta Royale interior lives again.
(Now to the part why they call me "Mr Nice Guy") I say, how far are you from Niagara Falls? He says, 15 hours driving time. I'm 3 hours more beyond the Niagara Falls, in Ohio. I was selling the "WHOLE" interior for $700. Door panels, power seat, switches, yada yada. I tell him, I'll bring it to Niagara Falls, final price delivered for $500 U.S. Currency. SOLD! This was in February. He picks a place, McDonald's near the Falls, crappy area. 11 AM on the next Sunday. My Lady Friend, the 7 years younger, thin blonde but very smart, and I love Niagara Falls and go there once or twice a year. (I say if you find something that works, stay with it. I discovered the "POWER" that Niagara Falls has on women by accident the first time I took a girlfriend there. We went there for the day but ended up staying the night. We did see the Falls when we got there and when we drove over the bridge back into the U.S.A. This was 1969 and I've taken all my Lady Friends there since, with similar results. As TV'S Hunter use to say, "it works for me.")
Turns out to be an unusual sunny Sunday in the 40s. We left at 6am, arrived by 9am. Scoped out the McDonald's. Then we went to a little local diner named the "Y" restaurant, because the roads are a Y.
Good breakfast, friendly people, bs'd with another couple, killed some time. Went back to the McDonald's, guy and his buddy show up right on time. Bing bang, move the parts to his truck, pay me and 15 minutes later we're heading for a beautiful day at the Falls. The buyer told me, a Trim shop had quoted him 7K in Canadian money to do the interior. We had a great day, ate supper in Erie, PA on the way back. Win win for both of us. The 1975 Delta Royale interior lives again.
Olds 307 and 403
Well-known member
Which gaskets are leaking? Most replacement head gaskets lower the compression FYI, only do if necessary. The rigid carrier valve cover and pan gaskets are nice upgrades along with a neoprene rear main seal, same as a Ford 460. Use the Right Stuff or Optimum RTV lines with the gasket replacement.
- Mar 25, 2020
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So I got my carb pulled off sent to get rebuilt... I checked my compression driver side was 180psi on all 4 cylinders /passenger side was 165 170 170 175... is this bad?
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