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#1
03-29-2024, 09:35 AM
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Novice question about intake manifold
What is the item to the left of the thermostat housing and what does it do?
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#2
03-29-2024, 09:59 AM
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It’s a thermal switch that controls the vacuum advance in relation to what gear the transmission is in.
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
| The Following User Says Thank You to steve25 For This Useful Post: | ||
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#3
03-29-2024, 10:08 AM
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Does it matter if the transmission is auto vs manual?
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#4
03-29-2024, 10:15 AM
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I forget, I am not home to consult my manual.
Most folks do not even have the needed vacuum solenoids any more that the switch controls, that much I can tell you. Also this set up was only for emissions purposes.
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
| The Following User Says Thank You to steve25 For This Useful Post: | ||
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#5
03-29-2024, 11:02 AM
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Yes, it's for the TCS system. It controls the vacuum advance based on water temp and also what gear your in and I thought it was used in both auto and manual cars. I have mine in place just for appearance but it's not functional, I don't have all the other components and personally, I think the motor runs better on manifold vacuum. Like Steve said, it was done purely for emission control.
__________________
70 TA, 467 cid IAII, Edelbrock D-port heads, 9.94:1, Butler HR 236/242 @ .050, 520/540 lift, 112 LSA, Ray Klemm calibrated Q-jet, TKX (2.87 1st/.81 OD), 3.31 rear https://youtube.com/shorts/gG15nb4FWeo?feature=share |
| The Following User Says Thank You to jhein For This Useful Post: | ||
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#6
03-29-2024, 03:08 PM
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Here's a better explanation of how it works from @Joe's Garage:
If the system is functional it energizes the solenoid that allows full manifold vacuum to the vacuum advance when the engine is very cold - helping with the choke system and idle during warmup. It also energizes the solenoid if the engine gets too hot either at idle or low speeds - applying full vacuum advance and increasing the idle speed to help with cooling the engine back down. In addition to this coolant temp sender activating the solenoid, it is activated by either a speedometer cable switch (on automatic transmissions) or a switch on the 3-4 shift lever (on Muncie transmissions) to allow full vacuum advance only in high gear on automatics or 3-4 gear on manuals.
__________________
70 TA, 467 cid IAII, Edelbrock D-port heads, 9.94:1, Butler HR 236/242 @ .050, 520/540 lift, 112 LSA, Ray Klemm calibrated Q-jet, TKX (2.87 1st/.81 OD), 3.31 rear https://youtube.com/shorts/gG15nb4FWeo?feature=share |
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#7
03-29-2024, 03:45 PM
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If I'm not mistaken it also ports vacuum to the flapper(s) on the factory air cleaner.
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If it breaks. I didn't want it in the first place. _____________________________________________ 69 GTO \ 72 FIREBIRD \ 1/2 OF A 64 GTO \ 70 JAVELIN \ 52 FORD PU \ 51 GMC PU \ 29 FORD PU \ 85 ALFA ROMEO SPYDER \ A HANDFUL OF ODD DUCATI'S \ 88 S10 LT1 BLAZER & MY DAILY DRIVER 67 SUBURBAN. |
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#8
03-29-2024, 05:45 PM
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Quote:
FWIW |
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#9
03-29-2024, 06:13 PM
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And is the most common vacuum hose left off by mistake as sometimes even pivoting the air cleaner base around to drop its locating tab in the carb will pull it off.
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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