Turbo 350 vacuum modulator line size. that the valve in the transmission case may be the issue.

Turbo 350 vacuum modulator line size. This low vac modulator will give you an earlier (and smoother) shift from first to second, and second to third. 050 intake/292@. Dec 30, 2009 · KevinW. - back home. They looked at it and said the vacuum line should be connected to a vacuum port directly on the manifold, ie. The TH350 gets vaccum from the intake manifold fitting located between the carb and dist. 050. I have a blown bbc and I have my th350 hooked up to manifold, at the time without much thought other than during normal driving I will have vacuum below the blower and the modulator will function fine and when I get on it, the blower will build boost and send pressure down 1967 - 1969 Camaro Transmission Vacuum Modulator Line, TH-400 Transmission Vacuum Modulator Line for 67, 68 and 69 models with Turbo 400. The pressure is increased in low vacuum conditions, i. I have run basic vacuum tubing from the big box auto stores carb to trans. that the valve in the transmission case may be the issue. Push in type, single red stripe. Helping a friend out and looking for the "proper" way to hook up the modulator. You’ll know it’s the TH350 if you have the fitting attached to the right frontal side of the transmission. This hose had to be attached to something, but what? :dontknow: Thanks! 4. I now need to hook up the line for the tranny vacuum modulator. I bought one of these vacuum connectors from the local parts store. Vacuum diagrams along with a lot more information is in the Chassis Manual. Apr 3, 2006 · The metal line was shaped such that it "nested" into the vacuum port. Jun 3, 2014 · Buy The Right Stuff CTV6903 Transmission Vacuum Line (Turbo 350, Right Hand Modulator): Hard Parts - Amazon. PART NUMBER: TRA-525 TRA-526 Share your knowledge of this product with other customers Sep 29, 2011 · If the hose is left off or not seeing vacuum, The shift will be delayed and very late. This line comes completely preformed with correct fittings on the ends. Select OE Steel or Stainless option. It tells the transmission how much load is being placed on it. #4 · Dec 30, 2009. 1967 - 1968 Chevelle Transmission Vacuum Modulator Line, TH350, Modulator on Drivers Side New transmission Vacuum Modulator Line for Turbo 350, modulator valve on left hand drivers side. The vacuum line size for a Turbo 350 transmission is 1/4″. 600 boreX4. 97 $ 49. The modulator uses vacuum as a throttle position sensor. com FREE DELIVERY possible on eligible purchases Amazon. 707 exhaust 109 LSA),Brodix single plane intake for a 4500 carb, Holley 1050 cfm dominator model # 9375, 2 inch primary Hooker super comp headers with 12 inch collector Turbo 350 Automatic transmission vacuum modulator line for your Firebird or Trans Am. So I have three questions. At hi vacuum, the force of vacuum opposes / cancels out spring force. Make sure your vacuum line isn't pinched and not allowing the vacuum signal to reach the modulator. Sep 18, 2019 · H 400 and TH 350 can use the SAME modulator. 31 posi. Find steel and stainless steel automatic transmission vacuum lines for Powerglide, TH350, TH400, C-4, C-6, Torqueflite & more. I have the 350 in my 37 Ford all timed and tuned. I stopped at the transmission place that rebuilt my transmission about a year ago. You can purchase this from TCI® or any GM dealer. Fits 67 & 68 Chevelle models. PART NUMBER: TRA-527 TRA-528S 1969 Camaro Transmission Vacuum Modulator Line, TH-350, RH Transmission Vacuum Modulator RH Line for 69 models with Turbo-350. LH side for 67, 68, and 69 Firebird models with Turbo-350 ( TH-350 ). is 1/4inch) and connected right to the manifold port. 55, Hotchkis, Bilstein, Global West, Morris Classic. Oct 2, 2006 · From the Summit Adjustable Vacuum Modulator instructions. 4,960. As vacuum drops, the spring exerts an increasingly greater force against the modulator valve, until at zero vacuum maximum boost is achieved. "To adjust the shift points of the transmission, disconnect the vacuum hose. The car will move however it wont shift automatically, it controls when the tranny shifts based on engine requirements. Kevin. Now, I knew that I had to had some type of vacuum source for the modulator valve on the tranny so I spliced into a line that was running out the back of the throttle body (TBI) to the MAP sensor. Mar 13, 2018 · Same size as the modulator on the trani. The diaphragm inside that modulator is obviously leaking and is not communicating the proper vacuum signal. There are many universal cable setups or you can opt for a factory replacement and stock brackets. M38 – Standard Turbo 350 manufactured from 1976 to 1981. Also included is an additional hose and oring to use later. So since the booster vacuum setup fits better, I put the booster vacuum into the rear center opening. If you pull this hose out and look in the opening there appears to be a very small set screw. So I thought I would run a hard line with two rubber lines on the end, the only problem is the nipple coming off the vacuum modulator looks like 3/8 and the line on the carb is much much smaller. 250 stroke)Dart Big "M" 4 Bolt Race Prepped Block w/Splayed Caps, GM iron square port heads, solid roller camshaft (286@. It will stop irritating late shift issues in the TH350 and TH400. Push in type, black & red stripe, adjustable. If a TransGo shift kit was installed, see Chapter 6 for further adjustments such as custom tuning the shift points by changing governor springs, removing the spring under the modulator valve, and Vacuum lines for turbo 350 transmissions with modulator on passenger side of transmission. Quick and easy. MX5 – Turbo 350C, 1982 and 1983 only. It runs from the back of the intake manifold to the modulator. Find the Vacuum Modulator. Nov 15, 2022 · How to Adjust Transmission Vacuum Modulator Turbo 350 . Tools Needed: Socket set; Screwdriver; Vacuum gauge (optional) Make small adjustments to the transmission upshifts by simply removing the hose on the vacuum modulator and turning the screw inside the fitting. Heavy throttle = low vacuum, so the modulator delays the line pressure rise and thus delays upshifts. $49. 1/4". Manufactured with computer precision on state-of-the-art CNC tube benders. Now clockwise, turn Jun 3, 2014 · Buy The Right Stuff FTV6903 Transmission Vacuum Line (Turbo 350, Right Hand Modulator): Hard Parts - Amazon. Oct 24, 2007 · The hard line is way less prone to develop leaks. 73 posi. I bought this intake manifold tee fitting, one end is 3/8 for my brake booster and the other end is 1/4 for my transmission vacuum modulator. The modulator affects shift firmness, and the shift timing as a "side effect". It is a brand new crate engine cam specs are. Jul 9, 2011 · Where exactly does the automatic transmission modulator vacuum hose get attached to on a Chevy 350? The way it is now, the carb's vacuum is attached to the distributor (which seems right) and the manifold is split between the master cylinder and the passenger side valve cover. How much vacuum does a TH350 need to shift? Does my engine have enough vacuum? What else could be causing the problem? Thank you in advance. Is there a vacuum line that must go on the transmission somewhere?? A guy was telling me about a vacuum modulator on the trans that I needed to hook up, or the transmission wouldn't work right. The Right Stuff CTV6903 Transmission Vacuum Line (Turbo 350, Right Hand Modulator) 5. Oct 10, 2021 · MX3 – Another Turbo 350 C code. Aug 1, 2009 · I put a 350/350 combo in my 56 chevy. Modifying the modulator raises the pressures inside the transmission and makes life tougher for the rubber seals and the pump. PART NUMBER: TRA-533-OE TRA-534-Stainless Jun 24, 2006 · My modulator vacuum line was plastic line/pipe (15/64inch outer dia. Keep in mind that adjusting the modulator is NOT the proper way to change the shift points. PART NUMBER: TRA-2156 Dec 7, 2023 · How to Test a Transmission Vacuum Modulator. Do I need to use the original metal line that runs from the intake to the trans? Or can I use rubber hose all the way instead? If I Dec 31, 2006 · Modulator is for LINE PRESSURE BOOST, and here's how it works. I was wondering. May 9, 2022 · What is a Vacuum Modulator? The vacuum modulator is responsible for controlling the shift points of your transmission based on the engine load. M33 – This standard Turbo 350 code identifies it as a standard Turbo 350. 12331 posts · Joined 2000. 1. . A leak in the vacuum source creates BIG problems for a Turbo 350 ( or any transmission with a vacuum modulator ) It also looks a good bit more professional and less " rigged " Jan 5, 2020 · The vacuum modulator needs to be hooked up to full manifold vacuum. This version did not have a locking converter. Reconnect vacuum line. If you try to run a rubber hose the full length the hose will eventually get soft and suck together which will not allow vacuum to get to the transmission. May 14, 2020 · Get the Best Performance with JEGS Transmission Vacuum Modulator for GM 1963-1990 TH350/TH400 [Adjustable] 62068 parts at JEGS. Manufactured from ’76 through ’81. You should have at least 15in of vacuum to make it shift correctly. Re: TH350 Vaccum Modulator Line. 435/. It is best to use a metal line for all but the connections at the modulator valve and if necessary at the intake manifold. With a flat blade screw driver turn the screw on the inside of the modulator end clockwise to raise the shift points and firm up the shifts. If you find the modulator is severely out of adjustment, then the transmission will not shift. This line is used to connect the transmission to the vacuum source, which is typically the engine. The B&M Adjustable Vacuum Modulator (Part# 20234) comes pre-adjusted for ‘normal’ shift points, but it is fully adjustable (see below), allowing you to customize the shift points (within a range of 2-4 mph). Disassembled & boxed. Adjustable for early or late shift. the same one that the brake power booster Aug 2, 2021 · I was told to get an intake manifold tee fitting and run the vacuum modulator straight to the T fitting on the intake manifold to provide the full manifold vacuum required for the modulator. To the best of my recollection the steel line was free floating within the two hose ends. Posts. I'm looking at where to plug the vacuum line in for the TH350. Shop Summit Racing now! $5 Off Your $100 Mobile App Purchase - Get the App 04-26-13 07:00 PM - Post# 2339352 In response to JoeyBoots It needs to be hooked up to manifold vacuum source, or full manifold vacuum. Nov 29, 2020 · Try a vacuum gauge at the engine then try it again at the modulator hose end. Jun 28, 2020 · 3227 posts · Joined 2014. Fontana, CA. Vacuum can suck a line closed causing fast shifts & other problems. It's a must have IMO. 4. Jul 20, 2013 · On my 69 3/4 ton with 350 engine and TH-400 the line is steel and is held to the modulator and vacuum "T" with very short rubber hoses. watch this video in its Turbo 350 Automatic transmission vacuum modulator line for your Firebird or Trans Am. Sep 7, 2022 · The diagram can also be used to identify the correct hose for replacement. The TH400, also known as the Turbo 400, is a three-speed automatic transmission that was widely used in vehicles from the 1960s to the 1990s. (1969) Transmission Vacuum Line Set- Turbo 350 - Right Side Modulator The store will not work correctly when cookies are disabled. ) and it was connected to carburetor full manifold port. 69' SS-350 Convert, M20, 3. Remove modulator and valve. In fact, the "T" end of the steel line is more of a nipple that loosely slides into the "T" with the hose creating the necessary seal function. In my Aug 2, 2018 · On my 1940 Ford w. i was wondering. FREE delivery Jun 10 - 12 . Jun 11, 2010 · The transmission shop is saying that my engine probably doesn't have enough vacuum. 761 lift intake . Now I put a new hose, which is rubber hose (inside hole dia. Aug 3, 2023 · Winter Weather / Freezing Conditions - Always check for water freezing in modulator; if not caught and water freezes in modulator or vacuum line, transmission line pressure will spike to north of 600 PSI and case will crack in the rear: Install new governor gear and calibration kit for high performance: Governor Apr 5, 2015 · It's both RPMs and vacuum. The Turbo 350 transmission line diagram shows the different components and connections involved in this process, including the transmission case, the cooling line fittings, and the cooler itself. Dec 9, 2012 · The truck originally had a 700r4 transmission in it but it went bad so I just put in a 350 turbo tranny. 69 Camaro - 383, 700R4, 12 bolt 3. IT WORKS! and with hot engine too. 97. Apr 13, 2019 · The vacuum line consists of a metal line with vacuum hose on each end. Shop Now at the Guaranteed Lowest Price! $5 off $49 / $20 off $249 / $60 off $499 / $120 off $999* - Use Promo Code: GIFT 1978 - 1981 Chevy Camaro Transmission Vacuum Modulator Line For TH-350 Transmission vacuum modulator line for turbo 350 automatic transmissions. These can be fine-tuned within a narrow range by adjusting the tiny screw after removing the vacuum modulator hose. There should be strong suction present in the hose, showing the Recheck the oil level one last time, double-check the vacuum modulator hose connections, and then do some fine testing. The next step is to find the vacuum modulator. It won't shift or it will shift at really high RPMs if you don't hook it up Upgrading and Modifying the TH350 Turbo 350 Transmission. com FREE DELIVERY possible on eligible purchases The TH400 vacuum modulator diagram is an essential tool for understanding and troubleshooting the operation of the TH400 transmission. Oct 14, 2021 · I show and discuss that just changing the Modulator may not help anything. Dec 30, 2009 · TH350 Vacuum Modulator Line Where can the TH350 vacuum modulator line hook up to on the engine? Can it hook to the carb or doe it have to go to intake manifold? If it can go to the carb does it need to be on full vacuum or timed vacuum? If full vacuum can I just put a tee in the distributor vacuum advance line? Also what size is the line from Aug 18, 2009 · 12-1 compression 565 BBC Shafiroff short block(4. Exact fit for all 75 - 79 models with a Pontiac 400 engine and a TH-350 trans. Just a note, you need the other 3/4's of your cam. points can be lowered 5-6 mph by installing the gold spring in back of the modulator valve. I have a Lokar kick down on the 350 Turbo Hydro transmission. com: The Right Stuff CTV6903 Transmission Vacuum Line (Turbo 350, Right Hand Modulator) : Automotive Nov 10, 2007 · C3 Tech/Performance - Do I need to use metal line for trans vacuum? - I'm down to the wire with the 383 project and I am going to put the transmission vacuum line on tomorrow (turbo 350). If you have 'too much vacuum' then you need to fine tune the modulator, adjust it inside the nipple, or use a different modulator. 0 out of 5 stars. The short hose held the two together. Just my 2 cents worth. If vacuum is less at the bottom run a rubber hose from a good vacuum source to the modulator for a temporary test. Jan 27, 2006 · Specs- 350 engine, Edelbrock Performer EPS manifold, Holley 4160, TH350 trans (rebuilt w/shift kit), 3. 1976 through 1981 model years. This one is a steal on Ebay, Apr 1, 2010 · Hi. By adjusting the vacuum modulator, you can affect how your TH400 behaves during shifts, essentially tuning the transmission to your liking. 050 ex . Includes vacuum tube and very important oring. 1/4" might fit but it would leak and you would never get proper signal to the modulator. Aug 24, 2019 · I’m going to try to reduce the vacuum signal that my trans sees at the vacuum modulator from the intake by installing a reducer in the vacuum line. Oct 30, 2021 · Fairly sure the modulate is 3/16" vacuum hose size. Apr 19, 2020 · I went from a '72 350 to a '70 455. The modulator is at the back of the THM350. You can run the transmission without a kick down cable but you have to downshift manually. Please choose OE or Stainless. However, if you’re looking to increase its performance or customize it to fit your specific needs, there are several upgrades and modifications you can consider. 460 and 212/222 @. e. There are a few methods for testing a transmission vacuum modulator to determine if it is still functioning properly or failing: Check the vacuum hose: Inspect the vacuum hose connected to the modulator while the vehicle is running. If the diaphragm is bad you can get the same symptoms, but often it's associated with smoke from ATF being sucked into the intake manifold via the vacuum port. On the other end of that steel line was a "U" shaped vacuum hose that connected the steel line to the vacuum port on the modulator. The modulator is a spring loaded vacuum canister. By studying the Turbo 350 transmission line diagram, you can gain a better understanding of how the transmission fluid flows through the system. Exact fit for all 78, 79, 80, or 81 models. (See Figure 8) Insert spring on end of valve and install valve and modulator as removed. I’m going to snip the tip off of the side nearest the intake and leave the necked down side nearest to the modulator. They have color stripes, yellow, green and purple(?) I think were the Camaro Vacuum Modulator Line, Automatic Transmission, TurboHydra-Matic 350 TH350 , Zinc Plated, For Transmissions With Left Side Modulator, 1967-1968 Item EK-33-181934-1 Close X Dec 2, 2015 · Full/unported vacuum connections - Power brakes - usually connected to large port on the carburetor base, using a larger diameter line - HVAC to vacuum motors for heater/vent controls - TH350 or other transmission for vacuum modulator - vacuum valve in air intake - vacuum valves for various emissions controls Bruce Mar 19, 2009 · You need vacuum from the manifold to the modulator on the tranny to shift properly. Nick R. a 350 TH trans there is what is called a ( modulator ) brass in color that the vacuum hose plugs into. The hole in the rear center of the intake is sized for the TH350 vacuum & for the brake booster vacuum. Transmission Vacuum Line ; 1969-1972 Chevrolet Chevelle, El Camino, Malibu ; Turbo-Hydramatic 350 Transmission ; Right/Passenger Side Mounted Vacuum Modulator; OEM-Style Fitment; Original Material Steel; Sold Individually Apr 2, 2010 · Vacuum modulator line turbo 350 Jump to Latest 12K views 2 replies 2 participants last post by BedfordBoy Apr 3, 2010 A new made in USA vacuum modulator for TH350 and TH400 Transmissions, 1965 & up. Light throttle = high vacuum, so the modulator raises the line pressure for early upshifts. The TH350 Turbo 350 transmission is a popular choice for many car enthusiasts due to its durability and simplicity. Turbo 350 transmission vacuum line size. Start out with light throttle driving and note the upshift points. PART NUMBER: TRA-4009 1967 - 1969 Firebird Transmission Vacuum Modulator Line, TH-350 Transmission Vacuum Modulator Line. Therefore, we strongly recommend you adjust your Turbo 350 modulator following the steps below: Firstly separate the vacuum hose to adjust the transmission’s shift points. Just keep it clear of anything hot. Apr 14, 2016 · Vacuum line going to the th350 modulator. That's why the TH350 has both a governor AND a vacuum modulator. I have used different size ID hose and had no changes as long as ya get it sealed up with no vacuum leaks! I like to bend solid line and use a short hose at each connection. Oct 19, 2021 · The modulator receives a vacuum signal from the intake manifold (in most cases). Jun 4, 2010 · Location. I would not go smaller ID size. full throttle. This modulator has been stationed at the transmission’s side and there may be a rubber vacuum line connected to it. CT5015 - A new vacuum modulator for TH350 and TH400 Transmissions, 1965 & up. #15 · Jun 28, 2020. Adjustable modulator should be used with this valve body kit. Nov 17, 2006 · Does anyone know the size of tubing you need for the regulator on a TH350 transmission? i use 7/32" vacuum line on the transmission modulator to intake manifold Mar 13, 2018 · Same size as the modulator on the trani. ppnng vqcthb uqble mdc bwp uagxws ormwo flbpv ystpt hucte