Just read a thread concerning putting a Ford 9" in a GS. Any truth to a higher resistence or any other factor that would cause a loss in effective horsepower being lost in this area?Claim in that thread was a 20 hp loss. I already have a Ford 9" in the installation process, but wondered if this is a possiblity. Maybe just having the FORD name association is the loss. Maybe I should call it a Buick 9" to get my horsepower back:grin: Anyways, back to the issue, what da ya think guys??????o No:
Its the location of the pinion that makes the difference. On a GM 10/12 bolt the pinion is located closer to the ring gear centerline. The Ford 9" pinion is near the bottom driving the gear at more of a tangent. The ford is stronger as far as ring and pinion goes because two teeth are in contact at all times. Not so on the more effiecent rears so its easier to strip the teeth off a 12bolt. This pinion location puts pinion pressure against the housing of the 9" ford so very heavy cars or low 10sec or faster cars generally run a stronger part. My 69' slowed .2 with the 9" ford. I make up for it with wheels up launches.:3gears:
I'm in total agreement. The 9" is definitely stronger than either GM rear. You also have many other advantages over the GM's. The axles are bolt in. You can change the diff in about 30 minutes. Disc brake selections are readily available. You can get 31 spine posi's from the junkyard. I'm sure if I sat here and thought I could come up with more.
Factory ford spider gears are junk! I put a fresh ford 9" in my 69 skylark, buick 350 with a richmond 5 speed. Didnt get it out of the neighborhood and broke the spider gears with a 4 pinion carrier. That was with street tires when the car ran 13s.
Stock-to-stock.. I completely disagree that one is weaker than the other. There is inherent weaknesses in BOTH. My choice remains with the GM 12-bolt, for my own reasons. The Ford 9"'s BEST quality lies in it VAST ARRAY of available aftermarket parts. MUCH MORE SO than the 12-bolt! Especially with regards to gear choices, and the time to change them! But, this is NOT NASCAR, so why not just build up your own genuine GM rear-end with the closest available gear choice, and not worry if the ratio is 0.27 off from the perfect ratio?? And yes, the Ford pinion location HP loss has been well documented. As fact, Strange Engineering has been selling for years a 9" "12-bolt style" centersection thats supposed to address that very weakness!
Just some more helpful info. The Chevy 12 bolt and all GM rears for our are cars are called "Hypoidal" since two teeth are always in constant contact. Also, a magazine did a comparison test among the popular "race-use" rears including the 10 bolt, 12 bolt, Ford 9" and Chrysler 8.75. Guess which one was the most efficient?? Least amount of HP loss? You got it, Chevy 12 bolt. To me, putting a Ford 9" in a Buick, just bothers me!
gm rears suck in the late 80s, i had the much coveted 3.64 non ac gs optioned 10 bolt posi in my admittedly low horsepower skylark. at 4000 lbs and maybe 325 horsepower, running high 13s/low 14s, i twisted both axles one weekend and made junk out of the posi cones the next weekend. in the early 90s you were lucky to find a bearing for one of these things-avaliability for gm rear parts is much better today than 15 years ago. It cost me 1200.00 to put a moser 9 inch housing and axle package, with a new detroit locker carrier and a nw 3.89 ring and pinion in the car. car now runs high 12s/low 13s and the rear hasnt been apart since 1991, and rear has at least 200 passes and 50k plus street miles. the moser housing/axle package has gone up a whopping 100.00 since then. if i had it to do over again, even with the new aftermarket 12 bolt stuff, i would STILL choose a 9 incher. i prefer to drive and race this car, not worry about driveline failure.
I appreciate all of those that responded. I guess its about split in opinions, but I dont feel bad about using this rear end in this car. I believe it a stout piece, and will more than handle anything I can throw at it. I guess Im more of a person that tries to keep the integrity of the car Buick, but if theres an improvement that can be made,(and compared to what I had, its an improvement I will make it when it possible. This is a FORD design rear end. Never was in a FORD, but was made for a A-body GM product. I just dont get caught up in the crowd where if you arent all Buick, I cant talk to you. There was a kid that was at the Temple Tx track that was running a small block Chevrolet in his 70 Buick Skylark, and he was really taking a lot of razzing. WHY? He had a respectable ride, 12 second car if a remember right, not 8 different colors.One color and pretty nice. But had a chevrolet motor. Gezzzz, he probably didnt have as good of a time as he could have at this event because he was an "outsider". I talked with him in the staging lanes, and he seemed like a pretty good ole boy. I prefer to keep my engine Buick cause thats my preference, (at a great expense), but if I wanted Chevrolet, why is that so disturbing to people.Not many of our cars out here are all Buick. Lotta pieces built and designed to fit a Buick, but not manufactured or built by Buick.(like the rear end I bought) Not selling out. Its a choice. Guess I just dont see the big picture like others do. Probably had this little rant over reading Georges comment ( I do respect George and enjoy his web information) but dont get how some of the things I do in this car hobby could bother some people. Again George, Im not attacking you, and you are not alone in your thinking by far. Its a comment Ive heard more than once. I did not get offended, nor is this to imply that I dont want your imput. I DO! Anyways......Rant over....NOBODY get offended! Im here to have fun and enjoy the conversations with EVERYONE!:TU:
The reason why Buick nuts give other Buick owners w/Chevy engines trouble is the plain old "overuse" of Chevy engines in almost everything. Kinda like finding Chevy parts next to the VW Beetle parts at the local 7 Eleven. I have seen Chevy engines in Ford street rods, GM street rods, boats, dragsters, race cars, non-Chevy GM cars etc. It is too easy and too common. And.......the Buick engine is a superior engine. Give the view of devalueing the Buick brand when you install a Chevy engine. Or getting your Ferrari painted at Maaco. Just doesn't go together. Its your car and you can do whatever you want. Just wanted to give you a sound basis for making a well informed decision. Good Luck!
:beer :beer :beer Thanks George, I know how sometimes reading computer script can be interpreted in various ways, so I definitely didn't want to ruffle any feathers. I may do things that the hardcore Buick enthusiasts would find politically incorrect. I just want to have fun and enjoy the camaraderie with friends as opposed to not being accepted in a certain circle for having a wrong piece of equipment installed on my car. I think most of us all have the same goal......:3gears:
