I have a front engine dragster running a very mild 305 Chevy. So far the best 1/8 Mi. ET is 6.52 @101 MPH on 91 octane pump gas with a 600 Holley, and it's been fun and trouble free. But, there's something about it is just calling for a little boost from a small blower. I'm thinking a Weiand 142 or some other similar small blower. I'd be happy to start with just a few pounds of boost, maybe 4-6 pounds for a bit of a bump in HP. I don't want to blow the bottom out of the engine. I don't believe the "baby blowers" are even in production any more and I can't seem to find much in the way of tech info regarding pulley sizes to achieve a desired boost. Also, wonder how much additional space is needed for the drive belt in front of the existing lower pulley which drives a small alternator. I don't have a lot of room between the pulley and the small aluminum fuel tank in front of it. I'll probably have more questions if I continue down this thought path but perhaps that will get us started. Thanks in advance for info and your experience. Lynn
Trying to find a used unit that hasn't been abused good be difficult. Those are 2 lobe rotors. If the intake manifold wasn't mounted properly and the blower tightened down without checking, it could have run the rotors into the case. Same for any backfire. How much boost you would have is dependent on cam profile, head flow and the amount of overdrive. The new Edelbrock blower would be something I would look at for current measurements because I think they use the same harmonic balancer that you might have. In the race car world, moving a fuel tank is a small problem. You may be limited in fabrication skills but it can be a good learning exp. Measure a dozen times and them move.
Edelbrock has the E boost little blower set up still. I have used several B&M set ups over the years and for a hot street set up they are very fun.
With fabrication skills you can cut down drive , I can get measurements off top and bottom pulley thats about 7-8 for 350 , I also went from serpentine to 8 mm belt teeth, No slip Those small 140s ? try to keep around 6,000 -6,400 R s , With know how you can strip lobs
Back around 93 , with B&M on a little 400 ,6psi DD 3,500 pound car 7:20. Around same time 351 in 65 stang 6:90ish , over 7,000 R bent rotors with slipping serpentine belt
wfo guy....no problem to move the fuel tank or build a new one for that matter. I built the dragster from the ground up. The question about the pulley was trying to think of things that might need to be addressed. Seems even a simple change can require changing several other things. I understand looking at new vs used but I tend to be pretty snug with a buck. I'm just in the consideration stage right now and would have the luxury of time to look for a good package for a reasonable price. On my one question regarding pulley sizes, did Weiand and others offer various diameters for the top and bottom to speed up or slow down the blower to achieve the desired boost? Pulleys sized for a 350 or larger engine would likely boost my little 305 higher than I would want. Lynn
Thanks for posting that squirrel. Apparently you were posting while I was typing. That's really quite helpful to see that there is such a thing as a pulley size recommendation chart. Now, if I could only find the setup like that used for $1500 or $2,000 that would be awesome! Lynn
@lake_harley Yes, other bands of 144 s chart does not show top pulley size just part # I will tye to put my hand on pulley & give a size for part# , I donot remember seeing part # ,
From the B & M Tech Manual- Because the B & M has long been out of production finding pulleys could be a problem.
Sold this one years ago, worked great on a hot 355, 7lbs. boost out of the box. made great torque up to around 5000rpm. I was not crazy about the ribbed belt set up, they do slip at high rpm as mentioned. On the street was a lot of little blower fun.
I went threw one box of stuff ,I could put my hands on The B& M does not have part #s or marking on idler or pulley's 1998 stuff, The 8 mm coupler & idler stuff is RCD to fit Vortec Paxton B&M Kenny Bell
The attachment gives some supercharger capacities. There may be some errors in the table, but the entries at the smaller end may give you some ideas/options of what to hunt down. Please forgive the entries in red, for Norman superchargers. My research has focussed on them, and they are almost HAMB friendly Cheers, Harv
Have one on my Merc.......6lbs @ WOT. Belt will slip @ 6500, but don't go there often. Nice little piece.
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