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Cable Bob
01/28/2015, 03:37 PM
I've searched the past post but didn't find my issues with my Trans.

It shift great, through all gears, no clunk noise, no hard shifts, no slips with normal driving conditions. Runs great!

But when I romp on it to the floor it increases in speed then it seems to catch and it takes off like a rocket, almost like a slight hesitation then it grabs and goes. When it shifts to the next gear, the same thing, it's increasing in speed than it seems to catch again and off it goes like a rocket.

A good example would be a four barrel carb with vacuum secondaries and your car has low vacuum, when you romp on it only two barrels are working then you feel the four barrel kick in once you've reach enough vacuum.

Has any one else had this issue?

tom4bren
01/29/2015, 05:07 AM
Sorry, never experienced it ... I don't drive like that.:)

circmand
01/29/2015, 05:59 AM
I've searched the past post but didn't find my issues with my Trans.

It shift great, through all gears, no clunk noise, no hard shifts, no slips with normal driving conditions. Runs great!

But when I romp on it to the floor it increases in speed then it seems to catch and it takes off like a rocket, almost like a slight hesitation then it grabs and goes. When it shifts to the next gear, the same thing, it's increasing in speed than it seems to catch again and off it goes like a rocket.

A good example would be a four barrel carb with vacuum secondaries and your car has low vacuum, when you romp on it only two barrels are working then you feel the four barrel kick in once you've reach enough vacuum.

Has any one else had this issue?

I didn't know it was an issue

Cobrajet
01/29/2015, 08:54 AM
If you're really worried, maybe you can put your VX on a four wheel dyno and map the HP and Torque curves to see if your engine is falling out of its power range in the lower RPM range.

I believe what you are feeling is probably perfectly normal, and would be exaggerated by using larger diameter tires.

Cable Bob
01/29/2015, 03:26 PM
Don't get me wrong Tom, I'm not running the crap out of it I just never romped on it in the past and when I did it's not like it took off, after the RPM increased it jumped up and went. Like I said, what you'd experience with low vacuum with a 4 bbl carb.

Gregg thanks for the good advice, that was the next step I had planned. Want to dyno it before and after the Supercharger. Found a place in the next town over that has 4wd dyno. The tires are only P245/60/R18 so that's not an issue.

tom4bren
01/30/2015, 04:28 AM
Don't get me wrong Tom, I'm not running the crap out of it ...

Just rattlin yer cage dude.:)

One other possibility is that your timing could be slightly off. IIRC our engines have some sort of auto adjusting timing but if the timing belt is off by 1 tooth, then it could exhibit the symptoms you describe.

I just noticed in the Amigo this morning that I had a pronounced hesitation right around 2400 RPM. I'm also getting a whine that sounds like it could be the TB tensioner. I hope it was just a quirk & that it's running smooth on drive home tonight. BTW the Amigo has the 3.2L engine so very similar to the VX 3.5L.

circmand
01/30/2015, 05:57 AM
Don't get me wrong Tom, I'm not running the crap out of it I just never romped on it in the past and when I did it's not like it took off, after the RPM increased it jumped up and went. Like I said, what you'd experience with low vacuum with a 4 bbl carb.

Gregg thanks for the good advice, that was the next step I had planned. Want to dyno it before and after the Supercharger. Found a place in the next town over that has 4wd dyno. The tires are only P245/60/R18 so that's not an issue.

the supercharger reference I wonder if that is a factor

Cable Bob
01/30/2015, 03:04 PM
I just replaced the timing belt last weekend, wanted to take care of that before planting the S/C, don't want to take it apart twice. Plus I just wanted to make sure the trans is up for the additional HP since it will be the weakest link.

Last week I drained out 20 oz of trans fluid and added 20 oz of Lucas ATM Conditioner and through out the week it seems to be shifting better. I only put 10 miles a day to and from work and now have about 50 miles since adding the conditioner and I believe it may have done the trick....

Replacing the brakes/rotors tonight, now want to make sure it will stop, most important!