- Mar 25, 2020
I got a stock 425 in a 67 delta88 what kind of carb and intake should I run... any tips on this motor
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.
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 goodThat's a plus but there's still the rear gears problem and the weight of the bigger "girls."
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?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.
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.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...