Whats up Guys, I found a large bore 6-71 for sale for $900 and am wondering if its big enough for the 460 I'm building for my Tudor. Can any one tell me if its gonna flow enough or where i can find that info. Also, I've never bought a supercharger before, is 900 a fair price for a rebuilt with no pulleys or manifold? Thanks!
As far as being big enough, YES.......... A good deal, well you need to buy alot of parts to make it work on your ride. You need intake, belt, pullies, linkage, carb plate, gaskets, carbs,..............I would think about that.
How much hp do yu wanna build? 6-71 should be ok but bigger blowers are available. Your pulley diameter will dictate the drive ratio and can be used to dial it in - in regard to your engines cubic inches. Watch out for used blowers, sometimes they are more $ to get it working properly than they are worth. A guy should consider that most 6-71 came from trucks/buses and will have a million miles on them. Just because the guy says it's a rebuild does not mean that it's gonna actually work as designed when *new*. There are a lot of so called rebuilt blowers out there that are not worth owning. Buying a new 'kit' from a respected supplier can save headaches and cash over trying to work with that great "rebuilt" swap meet item and then, buying or machining all the stuff you need to make it work only to find out the rebuilt blower wasn't worth the effort. .
Thanks guys, I'm hopeing to be in the 6-700hp range when done. What should I look for in a used blower? Thanks
Personally I wouldn't even look at a used unit, Like fuzz said, you have to do allot of retro fitting for what could be junk. You cant really tell what you've got till the thing is running. I would buy an 871 for that matter, and I would buy a new one. Blowers have come down in price a little due to the fact most are going toward the turbo for power gains. Buying a new blower is going to save you money in the long run. Just save your money till you can purchase a set up with all the bells and whistles from one place. You will be ahead in the end.
Better check on an intake. I've never seen an intake for a 460, hampton used to make one based on a tunnelram intake and it took about a 10' belt. Hogan and other fabricators make them but we're talking a lot of money and a cnc/fabricated aluminum intake may not what you have in mind.
Well... From what little research I've done... IF the blower is good I could get the manifold for $700 and the drive setup for $1400 from BDS, and I already have the carbs and linkage. BDS wants about $4100 for a 8-71 kit for the 460 so I'll be about $1100 ahead, unless some one can point me in the direction of a company that has a better price on the kit...
Clearances. Peek inside and check the rotors and housing wall. That will tell you exactly where and how far it's been. In terms of a manifold, build one yourself out of 1and1/2 in. plate providing you have access to a machine shop and a good flowing 4B manifold.
If this helps, nobody is gonna be using 2 stroke detroits anymore, so cores, spare parts etc should become more plentyful.
try dyers in summit il, they make great kits and will help teck. it for what you want.as far as used, you have to look close at the vanes for scraches to the case(when the end barrings are weak). as for compession under 7 to 1 and on fords, o-ring the block and heads.
Can I ask if this engine is for the street ot just racing ? Before buying a used blower you should have a prfoessional look it over first . You might just be buying costly piece of garage art ! Have you thought about a super charger or turbo charger ? Or do you just want huffer sticking out of the hood ? You can get an awful lot of power out of goodies hid under the hood ! Just my 2 cents .
If you are piecing something together, I would go to RBS superchargers and buy a used checked out blower from them. Fair prices very knowledgeable and always a good supply of used stuff. If all your after is the bling factor, it doesn't matter if it's a good blower or not, but if you want it to run and be reliable, do it right, saves a lot of cussing and wasted money. JMO Lippy
Thanks for all the great info guys, keep it coming! The car is being built for the street, but will see some weekend passes down the strip. Its a '31 Tudor so I don't think turbos would look right on it, and I really want the look sound AND power of a big huffer.
I built a blower motor 15 years ago, I read alot about the sizes and types of blowers made. What I got from all the research was that for performance you should use a smaller blower and spin it faster. So what I did was use a 671 topped with two 700 Holleys then turned it slow. ( hey I wanted the big look) the motor ran fine , made gobbs of torque and ran hot ever chance it got. So if what you are really after is the shock factor, run the 671 underdriven. But if you want to bust some asses its better to run a small blower like a 144ci and buzz the shit out of it. So theres my two cents worth..
As somebody else noted, Get a professional to look it over. But, I have seen professionals tell people that things were all good and go ahead and buy it and people still ended up with a nice coffee table center piece or worse, a detonated engine. A so called professional doesn't have to guarantee his word and he won't be the one you go to for a refund when he is wrong. You'l be lucky to get a 'sorry' out of him. Save yourself a lot of headaches and bite the bullet for the extra cash. Blowers are not something you want to try and save money on cuz you won't know that it's useless untill your engine is running and you've spent hundreds on possible fixes with hours of lost time. Even worse, a poorly put together blower wiill send your rods whirrling around your crank in a symphony of thrashed block sidewalls and broken crankshafts. I personnely would not chance wasting my $10 or 15K engine by trying to save 1K on a used blower verses a shiney new polished kit. It just aint worth it. jmho. .
Figgured I'd post the add for it, tho I'm almost set on buying new This is a gm 671 blower large bore case and rotors, that has been converted to street application. It has a weiand front cover and drive. The rear cover is the nostalgic waterman bearing plate. It has new bearings, seals and gaskets. All clearances have been set. Thanks for looking! Location: it's NOT ok to contact this poster with services or other commercial interests <TABLE summary="craigslist hosted images"><TBODY><TR><TD align=middle></TD><TD align=middle></TD></TR><TR><TD align=middle></TD><TD align=middle></TD></TR></TBODY></TABLE>
I feel so bad about what can and does go wrong with blowers after reading this thread, that I think I will sell my rotors to Dyers and junk out the eight or ten that I have laying around. Used stuff just don't seem to cut it anymore. Of course I used to just junk them anyway so I am right back where I was ten years ago.
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