[techteacher5561]

Not sure if this is the best section for this but lets see,,,

Replacing the T2 intake on my 350 with a stock CI 4V intake. Noticed in the Ames catalog there is a Theromostatic Vacuum Control Switch, looks like it sends four vac lines- 2 to the carb 2 to the distributor.

Will I need to get this? The T2 had a big vac line going from the rear of the carb base to the brake booster. Don't see a similar location on the CI intake. But there are other holes available on the front of the intake

If my dist was up graded to a HEI do I still need the vac lines going to it. I've one pontiac manuel on CD but I didn't see anything in it on this.

Anybody do this before???? I know,,,, kinda backwards huh,,, going from an alum. intake to a CI one. Definately adding a few more pounds back on but in other threads there seems to ba a strong support of what a CI 4V intake can do to wake up my 350.

Thanks HOward

[gto4evr]

typically, you run two vac lines off the manifold. One 3/8 to the PVC and one to the vac advance. I've never had an HEI to comment on it. What carb are you running? You usually run the brake booster vac off the carb base. That thermal vac switch is only for controlling ported vacuum so if you're not after originality, you don't need it. depending on the year of the manifold it will have either 1 or 2 holes on the fluid runner (one for the vac port and one for the temp sensor) you can either plug one off or use it for an aftermarket gauge while keeping the idiot light functional as well (depending on how you're optioned)

[goathead68]

Howard,

You don't need to use that thermostatic switch. Just run the brake booster off the base of the carb and the distributor vacuum off a ported source on the carb.

One of the holes on the intake, in front of the carb, was used to operate the heat flapper door in the air cleaner snorkel. Like gto said, there should be one or two threaded openings in the coolant runner.

What's the date code and part number on the intake?

[techteacher5561]

GTO4evr, carb is a holley 600cfm 4012 model (yes,, kinda an odd ball)

Goat head, yes there are two threaded ports in the coolant runner, on the T2 they had the original temp idiot light plugged into one and the after market temp gauge in the other.

I can't remember if my buddy (also a member here) told me what it came off. heres some numbers: on the coolant runner L028, upper runner 849667, lower runner 9794284 (Tough to tell on that first # mighht be an 8 instead of a 9). Not sure which is which and far as model number verses date code. These mean anything?

oh yeah, no heat riser off the exhaust manifold either, just an aftermarket chrome air cleaner appr 14" dia.

heres some pics if that helps.

Howard

[goathead68]

Intake is a '69 standard 4bbl. Attached is your pic with some printing on it.

[techteacher5561]

GH68 thanks for the info. Good to know where the stuff originally went. where you put "heat for theromostatic choke" it is a "recess" so did part of the original Qjet hang down there and absorb the heat off the intake? I figured I'd need to get a 90 degree fitting to connect the line for the brake booster, T2 had a straight fitting which doesn't look like it'd work any longer.

Howard

[gto4evr]

Original choke was a spring sitting in that recess inside a little sheet metal shed. An arm ran up from the spring to the butterfly. The original PVC fitting in Goathead's pic was a right angle with a little tube that ran down inside the manifold. Not really clear why the tube would need to be there as it works fine with a regular fitting (maybe someone can chime in on that one?) Forgot to ask if it was an auto or manual transmission. If auto, you'll need to T off the line with the brake booster.

I don't know if it was a typo or not with goatheads comment but the vac advance should go to full vacuum, not ported. (been a ton of threads on that one and basic consensus I can gather is that ported vacuum only helps emissions, NOT performance and can be a large factor in engine overheat during long idle conditions (see that monster thread in the cooling section with the sticky by George)

[goathead68]

Originally Posted by gto4evr

I don't know if it was a typo or not with goatheads comment but the vac advance should go to full vacuum, not ported. (been a ton of threads on that one and basic consensus I can gather is that ported vacuum only helps emissions, NOT performance and can be a large factor in engine overheat during long idle conditions (see that monster thread in the cooling section with the sticky by George)

I've never had a problem with overheating under idle conditions when using ported vacuum as a vacuum source for my GTO's distributor. I'd suggest you try ported first, if you have problems with that, then try full vacuum.

[gto4evr]

Originally Posted by goathead68

I've never had a problem with overheating under idle conditions when using ported vacuum as a vacuum source for my GTO's distributor. I'd suggest you try ported first, if you have problems with that, then try full vacuum.

Goathead - hey, sorry if you took my comment as a slam - I didn't mean it that way! I've also never had a problem with ported vacuum causing overheat. This site is loaded with guys way more knowledgeable than me on poncho's and I was just relaying what I've come across as the ported/non ported issue was something covered in a few threads here at PY.

Later,
Dennis

[goathead68]

Originally Posted by gto4evr

Goathead - hey, sorry if you took my comment as a slam - I didn't mean it that way! I've also never had a problem with ported vacuum causing overheat. This site is loaded with guys way more knowledgeable than me on poncho's and I was just relaying what I've come across as the ported/non ported issue was something covered in a few threads here at PY.

Later,
Dennis

Hey Dennis,

No offense taken! There is a lot of knowledge posted on this site and it was good of you to suggest an alternative vacuum source.

Some will swear that non ported is the way to go, others will say ported. I've always tried to set my stuff up using a relatively stock configuration and I've been lucky that it's worked for me. However, every car is different and what works for me, or you, or Howard might not work for the next guy.

Ken

[techteacher5561]

Ported verses non-ported?

Sorry to ask what is most likely a dumb question, but what is the difference? or how would I achieve either of these? Is it just "where" I hook the vacuum line? Ported is off the carb and non-ported off the intake? or is it vice-a-versa?

oops just reread prior posts, lets see if I have this right. First go with ported off the carb, if it runs hot ( which is a worry of mine, yes I've read the monster sticky on cast iron impellors and this is why I pulled the H2O pump to check while doing the manifold swap) then switch to a non proted source which would be a vacuum source directly from one of the intake runners.

I see there is a label on GH68's post for the pvc valve on the intake. When removing the T@ I had found what appeared to be a pvc valve plugged into the (I think its called the ) valley pan- sits under the intake. Does this sound correct? I have to look back at my pictures to see where this line ran, don't recall right this second.

Thanks for the assitance on what are probably stupid questions. But as a newbie I gotta ask before I go do something even more stupid. :-)

Howard

[goathead68]

Originally Posted by techteacher5561

Ported verses non-ported?

Sorry to ask what is most likely a dumb question, but what is the difference? or how would I achieve either of these? Is it just "where" I hook the vacuum line? Ported is off the carb and non-ported off the intake? or is it vice-a-versa?

Ported is on the carb, non-ported is off the manifold. I'm not sure where the ported vacuum port is on your carb; the guys at Holley should be able to tell you that.

oops just reread prior posts, lets see if I have this right. First go with ported off the carb, if it runs hot ( which is a worry of mine, yes I've read the monster sticky on cast iron impellors and this is why I pulled the H2O pump to check while doing the manifold swap) then switch to a non proted source which would be a vacuum source directly from one of the intake runners.

This is correct. However, as we discussed in a prior thread of yours, if all the cooling and ignition system is up to snuff, you shouldn't have to worry about the vacuum source.

I see there is a label on GH68's post for the pvc valve on the intake. When removing the T@ I had found what appeared to be a pvc valve plugged into the (I think its called the ) valley pan- sits under the intake. Does this sound correct? I have to look back at my pictures to see where this line ran, don't recall right this second.

The PCV valve is located in the valley pan, in front, a bit to the passenger side. You'll need to get a 90 degree threaded brass fitting (on the manifold end) with a barb on the hose end, to attach the PCV line to the intake. If you need a pic, I'll go to the garage and take one. Let me know.

Thanks for the assitance on what are probably stupid questions. But as a newbie I gotta ask before I go do something even more stupid. :-)

Howard

Howard, there are no such things as stupid questions. All of us have different experiences with these old cars and have had to solve the problems they've presented us. Sharing that knowledge is what makes this place so cool.

[techteacher5561]

Goathead,
Thanks for your time on this. I think I'm digesting everything. I'm cecking my "before" pics to see where the lines were before disassembly. They do not appear to have been hooked up like a stock intake. Maybe this is one of the problems I had with "hesitation" on acceleration. There was also a lack of gaskets between the intake and carb spacer and the spacer and the carb itself. While not the end of the world it certainly could have had a negative impact to some degree.

With the T2, the vac line from the pvc in the valley pan ran around to the base of the carb at the rear. I was just looking at the old pics and it appears to go right into the carb not the intake. The vac line going to the brake booster came off a port in the manifold The T2 had a threaded spot just under where the carb mounts where a brass fitting was screwed in and the hose attached to the fitting 9if that makes sense)

Don't kill yourself trying to get a pic of yours, but if it's not too big a hassle it might help alot. No hurry too cold to work on the car right now. I'm still lining up parts and in need of removing the two broken waterpump bolts before I can reassemble anything.

Howard

[goathead68]

Howard,

Here's a few intake pics.





I run my vacuum advance off the ported vacuum port. Your carb, of course, will be different.



The base plate vacuum fitting supplies the power brake booster, trans modulator (I have an automatic), hidden headlights (I have those too)

[techteacher5561]

Goathead, what carb are you running? Once I get some spare money { if there is such a thing :-) } I'd like to go back to a Qjet.

I see spacer on yours also,, is this a stock piece???? I need a spacer to mate my holley to the spread bore intake. In looking at ones online I noticed alot of them claim to improve low end torque. That is one area where my car was really lacking with the T2 intake, wondering if I'll be improvign the low end torque with both the intake and spacer- kinda double dipping so to speak.

BTW, nice clean engine comparment you've got there. Hopefully mine will look half that good when I get done.

Howard

[goathead68]

Howard,

I'm running a Q-Jet off of a '70 455 full-sized Pontiac. Cliff Ruggles built it for me. The spacer is a Barry Grant 1" that I got from Summit. It did help the low end a bit. I get around 10 mpg in town and 16 on the highway with this carb and the car runs like a top.

Thanks for the compliments on the engine compartment. I had the engine out about three years ago to replace the oil pan gaskets. I checked the bearings, helicoiled stripped bolt holes in the timing chain cover, repainted the engine and installed RA exhaust manifolds at that time. Oh yeah, I replaced the heater blower motor and heater core while the engine was out of the car too, then installed a mini starter, redid the wiring for the starter and installed a 2 1/2" exhaust system from Pypes after the engine was reinstalled. It's a case of one thing leading to another.

[techteacher5561]

Due to financial reasons I'm trying really hard to avoid the "might-as-wells".

You know,,, well as long as I'm here, I "might as well" do this too, and as long as I'm going to do that,,, I "might as well" do this,,, and this,, and this,,,LOL

Unfortunately I'm not rich,,, well at at not in the financial sense,,, Family yes,, money no. LOL


My oil pan is a leaker too, not horribly, I'll fix it eventually, but no engine hoist at this time. The leaks are keeping my floor pans from getting too rusty as well. :-)

One of my buddies just bought the repopped RA exhaust manifols from Ames for his A body build. He's gone through a frame/drive train build, now he's looking for a body. He didn't want to move is brake lines and distribution block like he had to do on his 67 tempest when he added headers. I'd love to have headers but not sure how well they'd fit with the limited room and my 4spd linkage clutch stuff. Looks pretty tight. Course the RA exhaust is like 400 clams so thats a ways away for now.

One thing on the schedule is a remote stater solinoid. One of my buddies did one on his Firebird and it made a world of difference ont he heat soak and hard start issue. Fairly in expensive too. I'm also looking at doing a hidden starter disconnect while doing this as a little bit of a theft deterant device.

My current set up gets 10-12mpg. Definately think I can improve on that too. When I removed the T2 intake you could see evidence of too much fuel going into the intake and staining the alum. Not sure if this was a fuel leak down while the car was sitting or running too rich during operation. Maybe both?

Outside of the 2 waterpump bolts breaking, everything else came apart easily and this is a big encouragement to me, as it makes me more inclined to tackle the "next" improvement. Although,,, perhaps I should reserve this claim until after I reassemble everything and get it "running" again!!

;-)

Thanks again for all your help.

Howard

[AdamIsAdam]

My understanding is that unported is any vacuum source below the butterflies (manifold or carb base). Ported means a vacuum fitting above the butterflies. those butterflies are the ports.

[Steveski]

Highjacking an old thread here. On a high option '68, for correct vacuum line routing, should the AC and hidden headlight vacuum lines tee off of the power brake booster line as shown in the last photo 5 messages down? Should one of them tee off of the booster line and then the other tee off of that line?