Geez, I can't believe it's been 5 years since I've been here... 5 years, and I've done exactly jack, and squat, with my Cutlass Calais.
And, if anything, it's made me more indecisive. The one constant is that the 260 will be replaced with... something. Also, life sort of got in the way. It's sneaky like that.
(note to self: you did this to yourself, dude!)
I've literally gone from "build the 455 that I have" to "go with a modern E-Rod engine" to "Hmm, a mildly built 403 sounds nice and would use all my existing brackets, etc" and just spun myself senseless.
What's more . . if I've read the quick glances over some threads correctly, a Gen IV or Gen V from the E-Rod program will fit, AND, am I right about this, a 6L80 will go in as well, WITHOUT the need to cut a G-body's trans tunnel?
But then I recently saw Jay Leno's video where he's driving a 79 Trans Am with a Pontiac 400, and he said that, despite the low horsepower rating, the large amount of low-end torque made the car feel more powerful than the numbers make it sound, and very enjoyable to drive.
I *do* have a modern car... 2015 Mustang GT, so there is that. But when I think of my Olds, I start thinking "well, I should do aluminum heads, fuel-injection, etc"
So, various thoughts:
Engine:
That said, I'm strongly leaning in favor of the 403 at this point, though I don't have an existing 403. I figure that its rated power of 185hp and 320ft-lb stock, wheezing through a single-exhaust and super-restrictive 70s catalytic converter should be VERY easy to improve upon.
And then I start to wonder - won't that make the old engine start to cost about as much as getting an E-Rod? Which already has great heads, a modern intake design, heads/combustion chambers, pistons, valves, rings, etc; basically everything inside the engine is already up to the standards of today, and some of the kits even come with the front part of the exhaust system and catalysts. Uh, I think?
In any case, will the build of the older engines even match, or come close, the torque output of the modern ones?
At the moment, I'm slightly leaning toward a 403, but once I add roller cam/lifters and aluminum heads to the mix, am I killing cost-effectiveness in comparison to E-Rod LS3 or LT1?
I realize, of course, that getting one of those as a kit with a transmission (the Connect & Cruise) bumps the price up considerably. But if we stick for the time being with engine-only comparisons, how does it come out?
Any thoughts/suggestions and explanations as to what/how/why are greatly appreciated. Except for "get off your lazy butt and do something with the car already" because I tell myself that now
(side note: and yes, a full-on electric swap had crossed my mind, but that, from what little research I've done, is very cost-prohibitive)
And, if anything, it's made me more indecisive. The one constant is that the 260 will be replaced with... something. Also, life sort of got in the way. It's sneaky like that.
(note to self: you did this to yourself, dude!)
I've literally gone from "build the 455 that I have" to "go with a modern E-Rod engine" to "Hmm, a mildly built 403 sounds nice and would use all my existing brackets, etc" and just spun myself senseless.
What's more . . if I've read the quick glances over some threads correctly, a Gen IV or Gen V from the E-Rod program will fit, AND, am I right about this, a 6L80 will go in as well, WITHOUT the need to cut a G-body's trans tunnel?
But then I recently saw Jay Leno's video where he's driving a 79 Trans Am with a Pontiac 400, and he said that, despite the low horsepower rating, the large amount of low-end torque made the car feel more powerful than the numbers make it sound, and very enjoyable to drive.
I *do* have a modern car... 2015 Mustang GT, so there is that. But when I think of my Olds, I start thinking "well, I should do aluminum heads, fuel-injection, etc"
So, various thoughts:
Engine:
- Old era engines - I don't care about hero horsepower numbers, but gobs of low end torque and great drivability. Smooth idle. Planning for peak HP to be at no more than 5000 RPM, maybe in the high 4000s range.
- Simple rebuild on 455, regular manifolds (decent headers are pricey for a big-block in a G-body, aren't they?), get some brackets to be able to attach the accessories. I already have a ran when pulled 455, though it's been sitting on a stand for over a dozen years. Stock from a 1972 Olds 98.
- Mild build on a 403 - everything I need to bolt all the pieces together are still there on the existing 260, hood clearance is nicer for a better intake, SBO headers are more available and less expensive.
- Stroker crank, or offset grind the journals? I'd personally be tickled if it came to 425 cubic inches.
That said, I'm strongly leaning in favor of the 403 at this point, though I don't have an existing 403. I figure that its rated power of 185hp and 320ft-lb stock, wheezing through a single-exhaust and super-restrictive 70s catalytic converter should be VERY easy to improve upon.
And then I start to wonder - won't that make the old engine start to cost about as much as getting an E-Rod? Which already has great heads, a modern intake design, heads/combustion chambers, pistons, valves, rings, etc; basically everything inside the engine is already up to the standards of today, and some of the kits even come with the front part of the exhaust system and catalysts. Uh, I think?
In any case, will the build of the older engines even match, or come close, the torque output of the modern ones?
At the moment, I'm slightly leaning toward a 403, but once I add roller cam/lifters and aluminum heads to the mix, am I killing cost-effectiveness in comparison to E-Rod LS3 or LT1?
I realize, of course, that getting one of those as a kit with a transmission (the Connect & Cruise) bumps the price up considerably. But if we stick for the time being with engine-only comparisons, how does it come out?
Any thoughts/suggestions and explanations as to what/how/why are greatly appreciated. Except for "get off your lazy butt and do something with the car already" because I tell myself that now
(side note: and yes, a full-on electric swap had crossed my mind, but that, from what little research I've done, is very cost-prohibitive)
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