Just curious if any of u out there have used carburetor spacers on ur caddys and what ur overall opinion is. Did u notice anything positive or negative gained from it? What size/brand did u use? I drive a 78 SDV with the stock 425, i recently purchased a 472/500 intake mani that i am planning on installing after i do the mod to the plenum, im thinking of throwin a carb spacer on with it n would appreciate any feedback or guidance in the correct direction as to what specific one would work best for my application, thx
Lordy be, finally someone in this section! And I haven't heard of those in decades. I'm sure even a little googling will pull up all the old urban legends:
-most legitimate purpose is transitioning between square and spreadbore carbs-to-intake
-next is temp insulation feature (phenolic) or cheaper alum. (zero insulation)
-give up lo-end torque for increased upper hp (strip)
More-bigger-longer-taller is nearly always better, except when it isn't. It really depends on your needs. That motor should already have plenty of off-line grunt. So do you plan on running near redline alot?
Others with direct experience with old Cady motors will want to know what else you've done on it. And I'm personally interested why changing the intake. Is that because just bigger, or was it an improvement in plane(s), runners, flow.....
Lordy be, finally someone in this section! And I haven't heard of those in decades. I'm sure even a little googling will pull up all the old urban legends:
-most legitimate purpose is transitioning between square and spreadbore carbs-to-intake
-next is temp insulation feature (phenolic) or cheaper alum. (zero insulation)
-give up lo-end torque for increased upper hp (strip)
More-bigger-longer-taller is nearly always better, except when it isn't. It really depends on your needs. That motor should already have plenty of off-line grunt. So do you plan on running near redline alot?
Others with direct experience with old Cady motors will want to know what else you've done on it. And I'm personally interested why changing the intake. Is that because just bigger, or was it an improvement in plane(s), runners, flow.....
Well from everything ive read on here n elsewhere online as far as lil upgrades n improvements for the 425, the 472/500 intake mani swap is what i read bout most often, ive read that it gives my motor a noticeable gain having gone from single plane to dual, theres also a mod folks do where u use a carbide bit n shave out the plenum n open it up some more, im gonna do that as well, just hopin to find a lil more detailed instruction of how-to than ive seen. I recently replaced my factory air cleaner with the edelbrock 14" open element, which was a lil tricky due to the diff design of the edelbrock bottom plate in comparison to my stock one, there was a clearance issue where it wouldnt sit flat on the carb, i ended up buying a couple sets of spacers that just sit on top of the carb n act as a booster seat for the air cleaner, stacked up enough of those n finally got it on there n luckily still had room for the hood to close without crushing anything, the spacers are just plastic rings n im not a huge fan, seem kinda chinsy n cheap, now this is where i started reading about carb spacers, i figure i could resolve the same clearance issue i had before by using one of those rather than what i currently have, plus it seems that givin the specific spacer used matched with the application it goin on people have been known to see some decent improvements in performance. Now im still new to all this so i was hopin someone could advise me on what kind/size spacer to use as opposed to goin out n buying one of each n testing them one by one to see what best suits my car lol
Ah so, I wondered if the old single-to-dual plane could have been it.
Ah yes the 'other' other valid use = clearing interferences. In my case it was doing a much larger dia. (and lower setting) factory air cleaner in an old Buick (which I also hacked in a second snorkel). And I used what sounds like the plastic ring idea you're using. I'd stick with that vs. performance compromises of a carb spacer = cheaper (you already have it), and no potential of having to re-calibrate the carb.
Carburetor spacers are a time-honored method of "tuning" an engine for a specific rpm/load band. A spacer and/or porting will do little or nothing for that 98% part of engine operation that occurs below wide open throttle, and can well reduce port airflow speed, thus causing poor gas mileage.
I've done a lot of engine modifications on Olds 455 and GM 454 marine engines - I owned a build and repair shop for 17 years.
Thk u all for the feedback! I really appreciate everything and anything y'all can throw at me. I dont have any friends who r into cars like i am so it is great to have a forum that i can look to for info, questions, knowledge, etc. I really enjoy working on my car n lately have been wanting to work on improving its performance. Ive been working on building myself an exhaust system every evening this week after i get off work til bout 10ish. Like most things with cars, it hasnt gone as smoothly as i had anticipated. I picked up the rear section of the exhaust (from front of rear axle n back) from autozone, its just a standard oem replacement, 2 1/4" i believe, but it is a "resonator delete" piece, as for the rest of the way forward i removed the muffler, cat, n remaining piping, i have a dynomax super turbo muffler a buddy had givin me years ago n the plan is to run 2 1/4" pipe n throw that dynomax in there with it, i gotta admit tho, driving to n from work the past week with straight header has been a blast, neighbors have already complained to the homeowners association that my car is vibrating pictures off their walls lol! I mean, yes it is loud n obnoxious but back in the day in the old neighborhood nobody woulda said anything, the changes that have come over the years in people, or everything really, it just doesnt sit well with me, i had no intention in keeping the car this loud but now just knowing the simple fact that people have complained, that alone really tempts me....but i am an adult now so thats how ill handle it
I installed the dynamax muffler off the end of the exhaust mani pipe where the cat converter was located, doin the full job was becoming too much of a pain in the butt, so ill roll like this for a week til i get paid again n search for a decent reputable muffler shop to take it to n either have them do the job, if price is right ill do the true dual set up. What is the part i need to get to make this possible tho? The 94-96 fleetwood crossmember? Is that all? Just got a few cans of gm blue engine paint so today i will start work on the 472/500 intake n exhaust mani's as well as valve covers, etc. All parts that were once blue that have since peeled, just clean n tidy up under the hood. Also, i need to get new bolts to install my new intake mani correct? Something bout the existing bolts probly have been stretched a lil from initial torque when installed? Hope u all r having a good Sunday! Back to the grind tomorrow....
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