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Supercharger fix;guage & plugs question

I'm hooking up a boost gauge at the moment, and wondering which vac line I should tap into. The destruction's suck. There is , what I think is a vac line coming off the top of the throttle body connected to the charcoal canister by the head lights. Would this be ok??:whistle:

FWIW there are several, what I would assume are vac lines coming right off the top of the TB.

Yellow goes to the canister , blue to some type of sensor for the SC, red to the PCV
TB002.jpg



Oh and also, can anyone enlighten me as to what this is thats floppin around in my engine bay with no home??


TB001.jpg

I hope that red wire isn't important.. then again everything has a home ..


Thanks
 
that's your fuel pump relay..

I would probably tap into the yellow, but I'm guessing any one of the 3 would work....
 
it's also a VERY good item, along with an ign module, to keep a spare of in your console....
 
oh, something else i was gonna mention to ya...

in case you hadn't heard, 700r4's absolutely hate heat... getting a cooler up front for that should be pretty high on your to-do list... and i would pay VERY close attention to that thing after your cable issues...

I will reiterate, if it isn't right, it will nuke it... if you have ANY doubts, it may be worth the $50 a trans shop would charge to double check the TV... a nuked one will cost WAY more...
 
ryoken said:
oh, something else i was gonna mention to ya...

in case you hadn't heard, 700r4's absolutely hate heat... getting a cooler up front for that should be pretty high on your to-do list... and i would pay VERY close attention to that thing after your cable issues...

I will reiterate, if it isn't right, it will nuke it... if you have ANY doubts, it may be worth the $50 a trans shop would charge to double check the TV... a nuked one will cost WAY more...
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Thank you sir, I did not know about the ignition module and fuel pump relay, I will stock and extra on the truck.

The trans does have a cooler. I will in fact find a trans shop to double check the cable and what nots. You are absolutely right, rather pay even $100 to be sure.

And Ryoken, I thought I might share this with ya. as I was installing this boost gauge , I was able to see behind the radio and , well.....

radiowiringbefore.jpg

:haha:



Thanks again sir
 
anytime, just holla... and yeah, previous owners of these rigs have a tendency to leave interesting wiring...

on that note.... one purchase that is always a wise investment for these rigs is a service manual for your yr.... usually they can be had on ebay for $25 or so, yr dependent... VERY nice to have a factory diagram.. I'd hook ya up but mine's an 87...
 
ryoken said:
anytime, just holla... and yeah, previous owners of these rigs have a tendency to leave interesting wiring...

on that note.... one purchase that is always a wise investment for these rigs is a service manual for your yr.... usually they can be had on ebay for $25 or so, yr dependent... VERY nice to have a factory diagram.. I'd hook ya up but mine's an 87...
Click to expand...

Why get a manual when I have this Place !!! Just kidding!! I have been looking around for a chilton manual at least but damn if all I can find local is the Haynes . Not a fan of Haynes manuals.

I WILL make this truck right and righteous. It'll take a bit, no doubt, got start with the drive train first. Once that good to go then it's time to have f'n with it (pant ,stereo, upgrades etc)

I hooked up a el cheapo boost gauge just now and Took for a spin, gauge only shows vac, no boost. I'm going to try a different location for the vac tap, if that doesn't work I'll try a different gauge. If THAT doesn't work, well I'll be wondering if this whole set up is even working
 
yeah, brainfart on my end, those are certainly vac lines, obviously not what ya need.. i would think it's gotta have a port for boost somewhere on it, maybe pipeplugged or something... is the one that runs to the sensor vac too?
 
ryoken said:
is the one that runs to the sensor vac too?
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Not certain what ya mean there.:confused:

The gauge is basically supplied with a small hose that taps into (what they say) a vac line and, the other end to a small compression fitting on the back of the gauge. Wires are for lights only.

The destructions say run of a vac, but , I dunno. I agree with what your saying, ya would think if you wanna read Boost, you wouldn't tap into a vac line :whistle:
 
right, I've never had to an install a boost gauge so it's a guess on my part...
 
ryoken said:
right, I've never had to an install a boost gauge so it's a guess on my part...
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Is all good. I just found this on SC forum. I can't believe I haven't found this before:haha:

"Anywhere below the supercharger int he manifold. If there is a plug it will probably be below the intercooler (if present) and in the manifold itself. Follow the bypass valve line to where it goes into the manifold. If a plug can't be located you can tee off the vacuum line that goes to the bypass valve servo"


Now, if I can just find the bypass valve servo :whistle:
 
A bypass valve would be similar to a wastegate on a turbo system. It opens at a set boost level so as not to overboost the engine which can, and will, cause damage.

Before SC is all vacuum side.
After SC is boost side. It's only a small area though between the SC and engine block/heads. Like Ryoken said, look for a small port that maybe has a pipe plug in it. I'll go back through the pics and see if something sticks out...
 
There is a small stamped steel bracket above your intake tube high up on the firewall. That should be what holds your FP relay. The red wire is to "hotwire" power directly to the pump, say if the relay fails or for testing purposes.

Is that a stock TBI intake manifold with the SC bolted to an adapter and then to the intake? Seems like a flow restriction if that's the case. Wonder if Whipple makes an adapter for an old 4 barrel carbed intake so you could swap that out for better flow. Project for another day, getting ahead of myself here....

What is that vac line that comes out the side under the SC, drivers side. Where does it go? That could be a place to tap into for the boost gauge.
 
496truck said:
Is that a stock TBI intake manifold with the SC bolted to an adapter and then to the intake? Seems like a flow restriction if that's the case. Wonder if Whipple makes an adapter for an old 4 barrel carbed intake so you could swap that out for better flow. Project for another day, getting ahead of myself here....

What is that vac line that comes out the side under the SC, drivers side. Where does it go? That could be a place to tap into for the boost gauge.
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I have NO idea :dunno: I figured you guys might know by looking at it lol

That filter set up, temporary, just till I get a better intake made.


TBandvac001-1.jpg




I see what y'all are saying. I see that line your talking about here?

(That breather is temporary :rolleyes:)

TBandvac002-1.jpg



I didn't tap into to that line, as it was dark and I didn't see it. I found one directly opposite to that that I thought may be going to the bypass, of sorts. Pic below altho that particular hose is under the mess. But it connects to a sensor dude that connected to a diaphragm looking dude. (see arrows) The other would have been far easier to get to:whistle:

TBandvac003-1.jpg



Thanks guys! I am off to NAPA for a new diff cover, my has a crack :doah: but first going stop by AAMCO and see about that TV Cable.
 
okay, so I tapped into both of these lines pictured, and I am still getting the same results. At idle it shows 20, under mild acceleration its jumps to 10 on the vacuum side.. Shows no boost :dunno:


I'm at a loss here. I guess I could try another gauge.
 
Boost is a measure of positive pressure, it needs to be measured somewhere after the supercharger. There may not be a ready made port for it as it's less common to need one on a SC vs a turbo set-up. It's engine driven, max boost is rpm based and limited by pulley sizing. IIRC those whipples were set up for approx 7 psi max.
 
tRustyK5 said:
Boost is a measure of positive pressure, it needs to be measured somewhere after the supercharger. There may not be a ready made port for it as it's less common to need one on a SC vs a turbo set-up. It's engine driven, max boost is rpm based and limited by pulley sizing. IIRC those whipples were set up for approx 7 psi max.
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How am I supposed to know if its working ? :haha: I also have read somewere that about & lbs boost is about what its SUPPOSED to be. As much mickey mouse crap that been done to this truck, I really want to make sure it's all working proper. I planned to also add a fuel pressure gauge and after I redo my exhaust, an EGT gauge.

I hooked this thing up per instructions I've read at a whipple forum, There not much help there.


correction ..After checking out a few videos, the gauge may in fact be working. All the videos I've watched so far , there gauges show vacuum until they lay into that throttle. I really haven't done that yet. Guess I'm reluctant to do so, afraid of blowing up something :weapon9:

Thanks
 
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On a second note, I want to change plugs and wires etc on this thing, I "hear" that I am supposed to run cooler plugs??? Anyone care to enlighten me???? :popcorn:
 
Just go lay into it and see if it makes boost. If I remember correctly the last time I drove my brother grand national which is a turbo it only showed boost when you really laid into it.

And on the plugs there are a couple different ac delco plugs that are all for sb but the last number is different and that is the heat rating.
 
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