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Topic Review (Newest First)
08-12-2009 06:18 PM
camaroman7d The plugs circled in the pictures are water ports, they are directly over the water jackets in your heads.

Putting the fitting it the pop off valve will work fine, if you don't want to drill and tap your manifold. Take a look at the back of the manifold on the same surface as the pop off valve, there's usually a fitting or two there.

Your tranny shifting issue is due to the govenor, there are kits out there to modify the govenor and prevent early shifts. I like to make mine manual so I lock out the weights on the govenor. Leave the modulator hooked up and hook it up above the blower, that way you don.t need any check valves. You will always have vacuum above the blower.
08-12-2009 01:55 AM
bentwings A simple place to put the vac/boost fitting would be in the pop off valve cover. It's the thing with the 2 springs on it at either the front or the rear of the manifold. Just measure the height of the springs before you take the plate off. Reinstall them at the same height. This will be a quick and dirty way to install the fitting. You can put it someplace else later on.

My T-350 is set up without a kick down at all. I just manually down shift it if I need it. I still use the modulator however. If I put the shifter in 2nd it will start out in 1st and auto shift up to 2nd depending on how hard I step on it. Easy driving it shifts pretty quick. I just hang 2nd for a while the go to drive. I can manually downshift at any speed practical. My trans is pretty firm. It has a B&M kit in it.


F-Bird... would it not be better to hook the trans modulator up to the carb as normal. The carb will see variable vacuum depending on throttle position. At WOT it is possible there may be a little higher than normal vacuum in the carb however I would think you could adjust the modulator to compensate for this.. I've only run manual trans with all the blowers I have installed so I'm learning here too. I understand the check valve to prevent the boost from getting to the modulator and you will have very high vacuum at part throttle and coast in the manifold with the blower.
08-11-2009 07:39 PM
uplateagain Thanks for the input. i never checked to see if the vacuum modulator was hooked up. wouldn't it shift hard, (like jolt) when it shifted through the gears if it wasn't? or if not enough vacuum?
I was told the transmission was built up, and had a shift kit installed. but thats words from the previous owner.
It always shifted fine when in drive through 1st, and 2nd, but happened very fast that you were in drive almost immediatly.
As for the kick down, there is no cable installed. with the 456 gears i can't see a need for it, but when i change to 3:50, or 3:73's i may want to hook that up.
I will check again on the manifold for a fitting, but unfortunetly i don't think there is one.
Thanks again for your input.
Daryl
08-11-2009 03:49 PM
uplateagain Well i had some time to mess around with the car today. The car would never manually shift into 1st, or 2nd gear, only drive. Whenever i would take off out of the hole it would shift so fast that 1st, and 2nd really never did anything, it would be in drive before 20 feet and low rpms. (also no kick down hooked up)
I found that the shifting cable was hooked up wrong, and that the previous owner put a pin in the ratchet shifter so it couldn't be manually put in 1st, or 2nd. I have no idea why, (maybe he was afraid of it lol).
But all i can say now is, this thing came alive now that i can get the rpms up off the line. Its a whole new beast. Now its FUN to drive.
I have put about 200 miles on it in the last 2 weeks and the wow factor was there for the looks, but it wasn't impressing me with the power factor. I can now say i have a smile on my face when i launch it.
I am looking into the websites, and books mentioned as i want to learn all i can, and also with the timing if anyone can break that down for me.
Still unsure of where to hook up the vac/boost gauge also.
Well just wanted to let you guys know the update.
Thanks,
Daryl
08-11-2009 01:41 PM
uplateagain Hello again, and really appreciate everyones help with this.
I just got my vac/boost gauge today. I looked on the manifold but only found the pictured fitting. There is one on both sides of the rear of the manifold, but not sure if this is where to hook my gauge up. Looks like it is right on top of part of the head. I drew an arrow to what iam talking about. Please let me know if i can install my fitting for the gauge in this spot.
As for the timming i didn't get a light yet, plus iam unsure of how to check it. Any info on this would be very helpful also.
As for the torque converter would it be a good choice to get the 3000 stall? should it be a 10", is there any thing i need to do to fit a 10" converter, or is it a direct fit?
Thanks again for everyones help, and for your kind comments about my car.

Here is the picture of the intake port iam wondering about for the gauge.

08-10-2009 07:34 PM
camaroman7d
Quote:
Originally Posted by bentwings
I zoomed in on the front cover of the blower in your pictures. There is a little red pushbutton valve on the right (pass side) of the blower snout. You should fill this cover up to the bottom of the hole where this valve is with gear lube. After that there is no need to ever use this pressure releif valve. The front cover will build what ever boost pressure the blower puts out. This helps the lip seals do their job. BDS is pretty emphatic about not relieving this pressure. So don't do it. Fill it and forget it. These blowers are designed to run for years without maintenance.

Otherwise start with a vac/boost gage and set the timing. then have fun.
Nice ride. The blower install looks pretty good. I'm green with envy.

I'm picking up my new blower carbs tomorrow for my new blower set up. Blower should be here next week and the drive the following week.
I was looking for the relief valve, but didn't see it until you directed me to it. My blowers have the valve in a slightly different location. I agree the bottom of that hole is the full mark.

Interesting BDS says not to relieve the pressure. Hampton blowers told me to release the pressure when I park the car for the day. I have always done it and never had any issues.
08-10-2009 11:05 AM
bentwings I zoomed in on the front cover of the blower in your pictures. There is a little red pushbutton valve on the right (pass side) of the blower snout. You should fill this cover up to the bottom of the hole where this valve is with gear lube. After that there is no need to ever use this pressure releif valve. The front cover will build what ever boost pressure the blower puts out. This helps the lip seals do their job. BDS is pretty emphatic about not relieving this pressure. So don't do it. Fill it and forget it. These blowers are designed to run for years without maintenance.

Otherwise start with a vac/boost gage and set the timing. then have fun.
Nice ride. The blower install looks pretty good. I'm green with envy.

I'm picking up my new blower carbs tomorrow for my new blower set up. Blower should be here next week and the drive the following week.
08-10-2009 09:40 AM
camaroman7d Kind of hard to suggest a stall speed without knowing the specs on the cam/engine. I would think 2500-3000 should be abour right (I would lean towards 3000). I also agree 4.56 gears are not a good combo for a blown motor unless you are planning to run 1/8 mile. Blowers make a lot of torque down low so you don't need a lot of gear. As mentioned you want the boost gauge connected to the manifold below the blower. Should have a a hole somewhere in the rear of the manifold, probably has a pipe plug in it.

Unless your blower is leaking you shouldn't need to worry about the oil, it can go many many years without needing any attention. Doesn't hurt to check though. There is a pipe plug in the front cover of your blower just to the left of the pulley, that's where you fil it.

Get a timing light on that thing ASAP and see what the initial and total timing is, this can make or break your power output and driveability. With 4.56 gears and stock conveter you should be smoking the tires just off idle.

Keep asking questions that's how you learn.
08-09-2009 07:41 PM
XNTRCI-T Nice ride, bud! Here are some perspectives on your questions... others may have a different perspective.

- with a loose (higher stall) converter, you will still feel some pull when you drop it in gear and you will still need to apply some brake pressure at stop lights, but when you mash the loud pedal it will spin up towards the stall rpm as you leave. It won't spin to the stall rpm unless you have a line-lock or trans-brake. You will definitely notice a difference, as the motor is winding into its power band as you leave.

- the boost/vacuum gauge tap comes off the intake manifold below the blower. There should be at least one NPT hole in your intake manifold. If not, drill and tap.

- use gear oil (70-90w) in the blower drive. There should be a filler hole in the front gear plate.
08-09-2009 07:36 PM
ericnova72 OK, you are misunderstanding how a torque converter works. They are a load and power sensitive power transfer device. The simplest analogy I can offer is that it is similar the centrifugal clutch on a go-kart or mini bike. Just normal putting around or takeoff from a stop a 3000 stall will act just like a stock converter with about 200 rpm more slip, you have to load it up(mash the throttle) to get the stall effect to be apparent. It is nothing like a neutral drop at all, more like slipping a clutch to get areally healthy stickshift to leave a stop light without squealing the tires.

The boost gauge is to be hooked to the manifold below the blower to read pressure, you will have to look to see if there is already a spot for it.

As far as the lube, consult the manufacturer of the blower for type and fill point and oil level.

Sharp looking car!!
08-09-2009 07:16 PM
uplateagain Just so my understanding is right. If i put a say, 3000 stall converter in, doesn't that mean that everytime i take off i will be doing 3000 rpm holeshots? almost like a neutral drop at 3000rpm? Sorry for asking such dumb questions, but iam just trying to learn.
Also once i get my boost/vacuum gauge, where do i hook it up to, the intake, or somewhere on the blower?
Is there a pre drilled place, or do i have to drill and install a nipple?
also what oil should i be running in the blower, and how do you check what oil it has, and where to fill it? (i know, its something i should know before even owning a blower engine)
once again sorry for the questions, but iam in new grounds with the high hp engine group. Basic, and mild engines no problem for me, but trying to learn as i go now.

I really do appreciatte any help all you guys are giving me.
Daryl
heres a couple pics of what iam playing with.

08-09-2009 06:12 PM
ericnova72 Your 11.5% underdriven. Your biggest problem is the stock torque converter. Car should be scary fast down low with 4.56 gears if the converter and timing is right.
08-09-2009 05:51 PM
uplateagain Thanks again for all everyones help.
I counted the teeth on the pullies and they are 61 snout, and 54 crank.
not sure on the timming or the boost yet, ordered a gauge but won't be here until monday.
the heads are AFR alum. 195 runners, and 68cc.
the trans, is a th 400, with stock converter,
ignition is msd 6 al, coil msd blaster 2, and msd dist.
The rear tires are 295-50-15, bfg radial t/a.
also mentioned is the 456 gear, dual holleys.
08-07-2009 09:05 PM
camaroman7d The very first thing you need to invest in is a boost gauge. Until you know how much boost the engine is making you will have a hard time figuring out what's going on with the power. You said the previous owner told you it is 13% underdriven. That iseasy enough to verify as mentioned above. Witha 6-71 on a 350 I would guess your boost is down around 8lbs, based on your drive ratio. You are doing the right thing by asking questions and trying to learn. What you don't know can kill that engine. I highly suggest you buy and read the book "Street Supercharging" by S/A Designs. It will really help you understand what's going on.

Ignition timing and timing curve is very impoortant and will make a major difference in performance and engine cooling.

ISince you don't know all the info on the engine, provide what you can. Verify your drive ratio, check your initial timing and total timing, install a boost gauge and verify boost.
08-07-2009 10:14 AM
bentwings The above info is pretty good. Get the car running good and drive it around for a while before you start changing things. It has to be a fun car to drive. You will probably blow off a set of tires pretty quickly. haha BTW you can get a nasty ticket or group of tickets if you aren't carefull.

I'd take a carb off and look inside the blower. Pop the belt off too and spin the blower by hand. It should turn freely and not be scored or chewed up. If it is you will definitely be down on boost. No easy or cheap fix here. You will have to send it to one of the blower shops for a rebuild.
The things are heavy. Around 70-80 pounds.
$300 up pluss massive shipping.

You can get a vacuum/boost gage from autometer in several different styles. Get one. Install the 1/8 npt fitting in the manifold under the blower. Yes there will be vacuum in the manifold even cruising. You will only get boost when the throttle is open far enough for the blower to draw in more air than the motor can by itself. The 6-71 blower displaces 411 cu in per revolution and is quite efficient at relatively low speeds. You have to overcome vacuum before you get boost. It happens pretty quick however. Don't get too carried away with boost on the street. 5-8 psi is good for a SBC You could go to 10-11 underdrive and pick up a little but I'd be carefull. The more boost you have the more critical timing and carb tuning becomes. The first time it backfires hard will open your eyes for sure.
$60 or so

Try your converter out for stall speed. You really need about 3000 stall even with the blower in this case. I've got a 3k in mine and it really made driving it more fun.
$350 or so

The 4.56 gear are going to be a major pain on the street. I ditch them for a 3.73.
$175 +/- a little. If you install them yourself.
add another $100 minimum if you don't.

Instead of messing around with the timing light trying to figure out the advance curve just take the distributor to a good performance shop and have it run on the Sun machine. Tell them you want full advance by 2000-2200 engine rpm and about 15-16 degrees of advance. Install the dizzy and set total advance at 28-30 degrees at about 3000 rpm and let the initial fall where it might. All you need to worry about is that it doesn't kick back against the starter. It shouldn't with proper C.R. With this set up and a 3k converter you will have full advance almost anytime you step on the gass.
$50-75 about.

I put a few $$$ figures in to give you and idea of the cost of blower related items. As they say "...get used to it"
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