Hello All. Im new here(intro in intro section) and Im building a blower motor for my hotrod. I was wondering if I give you the specs of my buildup, if you could give me an idea of the horspower n tourque I will get from it? I was also wanting to hear from others who have ran blowers to see there likes, dislikes and recieve any info they can give me on them. I hear there totally different than a normal carbed engine. Thanks for any help. HG Heres my setup so far. 355ci sbc steel crank n rods Speed pro forged blower pistons/Moly rings 465-485 X 270-280 cam W/224@050 and 114 lobe seperation. 2200-5800. Edelbrock alluminum rpm heads. 70cc chambers @ 170cc runners yields 8-1 comp ratio. Luinati roller rockers MSD pro billet dist, recurved to Weiands blower specs @ a MSD6AL box and a blaster 2 coil. 2 Edelbrock 500 carbs that came off a friends blower motor so its jetted for a blower motor. Weiand 6-71 blower running 8lbs of boost. Sanderson (hopefully if they fit ) 1 3/4 inch block huggers 3 inch duals with 3 inch (?) Flowmasters Just trying to get a good guess as the power level. Thanks, HG
if i had to pull a number out of my ass, i'd say it's good for 6-700hp. but the reason i posted, i'd suggest running a MSD 6BTM instead of the 6AL, it will pull timing out as you make boost.
I've got the 6AL on my blower motor, and it pings a bit under boost at high RPMs. If I were to do it again, I would definatly go with the 6BTM over the 6AL.
We just finished a blown basic/old school 355. GM 4 bolt "010" block, main studs, H-beam rods, .030" over custom Ross flat-top blower pistons. Ported but otherwise stock iron GM large chamber heads w 2.02/1.60 valves. 8.5:1 compression ratio. Crane CC-300A (revised grind number is F-300-2) mechanical cam (264/272 dur @.050" - .563"i/.588"e lift, 112 degree lobe separation) GMC 671 (mid sixties vintage) from "Ohio" George Montgomery's shop with Pete's Engine Co. magnesium end plates and an Isky snout and drive system. With the blower 9% overdriven it made over 700HP (and climbing fast) at 7000RPM and 500ft/lbs from 3000 thru 7000RPM. They dyno operator wouldn't push the motor past 7000RPM.....it would have made power to almost 8000 if the heads could support the airflow needs. Our carbs were bigger and our dyno headers were much better than the shorties your going to run. We're making more than 8lbs of boost on this motor. We're running race gas so the tune-up is much more aggressive than what your going to run on pump gas. Our cam is much larger than what your running too. Your heads are as good as if not a little better than the ported stockers we're running...so you'll pick up some HP from there. Honest guess at your HP numbers? With a conservative tune-up, 8lbs of boost, with those carbs and those shorty headers.....you'll probably make 500-550hp. I have another buddy running a very similar set-up to what your planning on and he made 580hp on the dyno....but with more cam and good headers. Good luck with it and welcome to the HAMB. -Bigchief.
Thanks for the replys fellas. I was gonna use the BTm box, but my friend had one and didnt care for it. He also said with me limiting my revs to 6 grand and under, that it should never get into detonation???' I just went with his 2 cents. HG
Uhhh, detonation can occur at almost any engine speed. Don Hampton at Hampton blowers has been very helpful in the past when it comes to combinations and tuning. Look him up and give him a call. -Bigchief.
if the compression is at or below 8:1 you will probably be ok as far as detonation...I'm running 7.5:1 and 7psi in a blown big block an never have heard a rattle out of it on 87 octane with highway gears (!) The 550 hp guess sounds pretty close to me.
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