Mine has a screw in the port. My dad had cranked the thing to the moon where it'd only upshift damned near WOT. I backed it off a couple of turns and it shifts a bit more normal.
TH400 Vacuum Requirement
- Thread starter mikester
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Mine has a screw in the port. My dad had cranked the thing to the moon where it'd only upshift damned near WOT. I backed it off a couple of turns and it shifts a bit more normal.
Stock modulators are usually preset; for adjustability it has to have been changed to an aftermarket unit. For that you need a TH400 specific service manual or need to go cruising through the you Tube Videos to see if someone shows how it is done.
Curious at this point though, who dropped the cam in and did they degree it after installation? Your comment about speaking with Comp Cams suggests that they think the cam ought to deliver a decent amount of vacuum at idle so, if not, then why isn't it?
Nick
Curious at this point though, who dropped the cam in and did they degree it after installation? Your comment about speaking with Comp Cams suggests that they think the cam ought to deliver a decent amount of vacuum at idle so, if not, then why isn't it?
Nick
Ive known the guy that built the motor for close to 40 years. Hes a well know engine builder thats got a great reputation for building healthy motors. This is the second time hes built a motor for me. The first was a 396. I dont think he would have screwed anything up. I told him where I wanted to be as far as HP. He went over the parts list with me. I ordered everything and he assembled it all. After I got the motor back to my place, he came over and fired it up on a test stand. Ran it for at least 30 minutes. Put it in the car and he came over and timed/tuned it again.
When he paid you a visit, did he happen to throw a vacuum gauge on the engine while it was running? Has he driven it since it was dropped into the car? My only thought about all this at this point is that a combination of parts can look great on paper but not live up to expectations when assembled.
Nick
Nick
I just came in from the garage. Took your advice from yesterday. It was 8in at idle. Hit the throttle a few times and the numbers went up. Now Im going to hold off buying the vacuum pump.
When I put the Moser rear in I bought all new emergency brake cables. I couldnt pull the right side cable far enough to get it through the bracket that they all go into. I had the same issue with the wagon. Easy fix. Took it all apart. Got enough cable but I didnt have any 5/16 fine thread nuts to put it all together. Once I get the cable in right I'll put the brakes back together. Then I'll drop is back on the ground and take it for another ride. I also have to do some other stuff while its on the stands. One of the transmission cooler lines is leaking at the transmission. Not at the threads, in the center at the tube. Theyre SS lines. They were originally TH350 lines that I tweaked to fit the 400. Im pulling that line off tomorrow to make sure the brass fitting didnt get damaged from messing with it so many times. I also have a steel set from Inline that I used to play around with the bends. I just might stick them in since theyre more forgiving when you "adjust" them.
Its funny, when you think the majority of everythings done you wind up seeing little things that you just forgot about. LOL
That's how it starts. Soon he won't quite finish the bottle at the end of the night, and then before you know it he'll switch to swapping ls motors into everything he owns...
The slide begins...
They’re ugly and most people think of them as no needed, but pick up a vacuum reserve canister out of any luxury liner car or A/C car (little plastic ball on g-bodies) and plumb it in. Used is a couple bucks if they charge you.
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Yes and add a check valve.
The modulator with black stripe plus red stripe is specially made for low vacuum signal.
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