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Topic Review (Newest First)
08-27-2008 03:51 AM
LordTTK Thanks to all the help i got it running great

But for a week ago evertyhing went awfully bad, one "arm" in the carb got loose and went inside the blower so no more blower this summer
But atleast i have something to do in the winter now

07-24-2008 01:03 AM
rlflynt On my 78 GMC jimmy with a 350 and a quadrajet that port goes up to my air cleaner
06-02-2008 07:10 AM
LordTTK Hi and thanks for all the input.

I have this cam Crane #113801 HMV278-2
And i use the stock pulleys that came with the blower.
And i use a piston style 170 gph fuel pump.

Heres the pulleys thats on the blower
Crank pulley is 6 inch
Upper is 3.07 inch
06-01-2008 06:58 PM
Originally Posted by LordTTK
And the gauge don't show any boost when i drive it down the road under load neither
Do you know what your blower drive ratio is? With a 144 blower, you are only displacing 82% of what it takes to charge the 4 cylinders per revolution that will be on the intake cycle. So to get any boost at all, you need to drive the blower at something more than about 125% of the engine rpm. To get meaningful boost (more than about 6#) you need to drive a 144 at something like 2:1 on a 350.

Also, do you know what your static compression ratio is?

Here is a thorough discussion of technical info on Weiand supercharges.
06-01-2008 04:03 PM
carsavvycook That is the port I was referring to. I am finally enjoying my first day off in the last 30 days, and my memory is a little foggy, but getting better. Hopefully one of the Rochester Carb guys will chime in on this post, on how best to set it up for a blower. I have always used Holley and Edlebrock carbs pre-referenced for boost, when installing a blower.
06-01-2008 03:52 PM
LordTTK Look at this picture it shows what port i mean, its at the top middle rear.

And the gauge don't show any boost when i drive it down the road under load neither
06-01-2008 02:23 PM
carsavvycook If the port you were referring to is the port at the top towards the right side on the rear of the carb, this is a port that is used to draw air into the choke heater on a factory set-up. It relies on the volume of air being drawn through the carb. Plugging it will not richen it up enough on a blown application. As far as Boost, you will not see any revving it up parked, only driving it down the road under load.

Hope this helps.
06-01-2008 01:43 PM
LordTTK Hi, i checked the spark plugs they looked normal.
And i plugged the vacuum port on the carb.
And i made the return line from the regulator smaller.

So now the engine feels a bit stronger true all the gears, but it still lacks the last push if u can say so...

And one more thing i have a auto meter Boost/Vacuum gauge and i hooked it to the intake but it only shows vacuum???
05-29-2008 11:57 AM
XNTRCI-T It sounds like you are going lean at higher RPMs, which is a very bad thing. That's a sure way to kill a blower motor. Check your plugs for signs of detonation... little specks of metal stuck on the electrode and/or the ceramic, or chunks missing. Compare your plug colors to this chart...

spark plug color chart

There should be no open ports at the base of the carb. An open port is a giant vacuum leak, which will cause a lean mixture. The ports either need to be connected properly to the PCV, distributor (if you have vacuum advance) and your transmission if it has a vacuum modulator. If the port is not needed for the above, it should be capped.

I would not drive your car until you sort out the mixture issue. It may be as simple as capping that port.

Oh, and welcome to the forums. Lots of knowledgeable people here!
05-29-2008 11:34 AM
Rochester carb with blower

Hi all iŽam new to this forum i got a tip that this is a good place to ask about blower engines.

So heres my problem at the higher rpm my car feels like its not getting out all the power it wants, but in the low rpm it haves lots of power.
So iŽam wondering could it be the carburetor that donŽt work correctly?
Its a JET Streetmaster Quadrajet Stage 2 Carburetor

What rods and hanger should i use in the carb?

And if you look at this picture
Behind the carb you see a port what should go in there or can i just plug it?

Its a csb 350 engine with weiand 144 blower.
I use 95 and 98 octane gas "live in sweden"
if you wonder anything just ask and ill try to answer.

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