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iTrader: (5)

ahh. hopefully just something loose then. I have a lt t56 in the corner for a long time now for my car, but honestly I'm starting to think a 5 speed like your tko would be a better fit. size, weight, clutch and gear spread. never been a huge fan of the 2.66 1st gear.
the torque arm not clunking around would not be good thou haha.

dabomb6608

iTrader: (3)

Here is a datafile from a drive the other night. I told my wife that if it wasn't for the tires needing replaced in a bad way or the clunk from the torque arm I would start driving this car a lot more often on the weekends. Compared to before this car is incredibly drivable. Very little surging that likely is still tune related. I've got idle at 800 currently with about 45ish kpa. That is basically 100 rpm lower than before and about 10 kpa less as well. That alone shows the engine is running with less effort. I am currently concentrating on getting my fueling dialed down as well as keeping an eye on spark plugs for physical signs of detonation due to knock counts I am experiencing. On my latest tune I lowered a few areas of light throttle SA to see if that will help calm those counts down. I included my latest tune as well for your viewing pleasure.

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iTrader: (5)

thanks for the motivation, i finally installed the wud on my newer laptop and stuff for tunerpro to take a look.

would you happen to have the .dat log, just so i can see if i can get it to play thru on wud. i really gotta make some time to install this ebl. sadly i need up replace the fuel pump too. ugh i hate dropping the axle. but i started it the other day to clean the garage and i would bearly idle. im guessing the has gotten very bad. it used drop off about 3k rpm. but that was a while ago(3 years ago) haha.

dabomb6608

iTrader: (3)

See attachment for the .dat log

Fuel pumps are never fun to change out.

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iTrader: (5)

i might be doing the wrong, since i just loaded it up for the first time. but the attached log is a excel file, which works, but i was thinking you can open a log file with the WUD directly and watch it play thru? if so, it seems to be looking for a different file extension than .cvs for excel? or i might be trying to do something i can't haha.

no worries

dabomb6608

iTrader: (3)

That is my bad. I zipped the excel not the dat file. Here is the datalog file

dabomb6608

iTrader: (3)

Drove the car into town early Saturday morning to run a few errands. About 30 miles round trip with interstate one way on my way into town. As my tune gets closer and closer to a point it doesn't need constant monitoring and adjustments I am starting to note other areas needing attention. And right now my biggest concern is suspension/driveline.

There is a heck of a vibration throughout the car at highway speeds above 60 mph with a progression of severity the faster you go. Going down the interstate at 75 for 8 miles definitely gave me a wake up call of just how bad it is. I am thinking it is either U-Joints, Driveshaft Balance, Pinion/Trans Output Angle, or some combination of those. It is worth noting that this vibration was present with both the factory torque arm setup and the UMI setup I installed this winter. I kept the adjustment that the previous owner had when I installed the torque arm. I need to get an angle finder to confirm those. I do plan on swapping my springs out all around to get the car to sit a little higher. It has some cut Eibach Sportlines that I got second hand years ago. I think some new Pro-Kits would better meet my needs. As great as it looks, it sits way too low and I am sure that isn't helping my driveshaft angles at the back. Even with Koni Yellows the car rides like I am driving a rock due to frequent bumpstop contact.

Another concern I have is the clunk I have from this torque arm. It is pretty annoying. I need to get the car up on stands again to inspect everything just to be sure I've not missed something during that install.

???

iTrader: (5)

thanks for the file, that is the format. but i have the p4 wud and it says this log is something else. do you happen to have the flash 2? Just curious, no big deal. I need to just hurry up and make my own logs to look at lol.

its probably the drive shaft. I've fought with drive shafts for years with my 91 z28. I've changed my you joints, had shifts balanced and completely new ones built. all ended up being crap. what did best for me was stop by a junk yard. find a v6 automatic car. on the shaft rear u joints there's a little metal cross tab that holds the end caps on, I'm guessing during factory assembly. if you find one with that completely intact. it will be smooth as glass, once those rip. they all vibrate. I'm not going to pretend to kown why haha

sadly these aren't in the junk yards much these days. but if it get worse with speed, some speeds worse then others, as it hits different harmonic resonance. usually feel worse in the off throttle just coasting part and better under load. it's most likely drive shaft



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dabomb6608

iTrader: (3)

Yep I am running Flash (Old style before Flash 2 but same thing).

It definitely has a harmonic resonance to it. At highway speeds (70-75) it was like a slow harmonic up/down hum. Not sure if you've ever been on a twin engine boat, but best I can compare it is when the two engines are approaching the same RPM you can hear the harmonic hum go up/down slower and slower until they equalize out. My Yamaha Jetboat has twin engines. Rarely do I go off the RPM gauges, I just go off of that harmonic hum balancing out.

But it definitely gets worse with speed.

I'll have to look into that piece. Never heard of it/seen it. Definitely no good junk yards near me these days. Closest "U-Pull" style place is 2hrs in St. Louis.

???

iTrader: (5)

that's a 100% what my drive shafts sounded like. unless you have a ton of slop in the axle pinion bearing or rear of the tranny. but I doubt it.


I happened to score a oem aluminum shift for my 90 that was pretty good. not perfect but definitely good enough. I do believe a 4th gen shift is the same and fits our cars but you'd need to double check my memory haha.

hope it's an easy fix. these just seem to be the pickest cars about driveshaft vibration. especially the manuals.

dabomb6608

iTrader: (3)

Yeah they are the same 4th gen to 3rd gen as far as I can tell. I've got a buddy with a charged 4th gen and full suspension. I'm going to talk to him this weekend when I see him about his torque arm setup and if hes ever had vibration issues like mine. His is a T56.

For the prices I am seeing, I would consider snagging a aluminum shaft from ebay out of a 4th gen and throwing new joints in it just to try.

Tom 400 CFI

I totally agree. I've had steel, aluminum, they all vibrated in my 3rd gens. I even resorted to the hose clamp trick...which helped a lot but didn't totally eliminate it either.

'Vettes the same. I've had that shaft balanced, R&R'd the tail shaft bushing....thing still HUMMMMM's at 75-80 mph. Irritating.

I agree that a 4th gen shaft should fit.

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iTrader: (5)

try it before changing u joints. these are held in with nylon melted into them. it's almost not meant to be service. it takes almost nothing to distort the ears. you need the gm tools and enough heat to melt the plastic but not mess up the shaft.

I tell people about my struggle with these things and they say no way, I change u joints all the time. I'm like I've lost years off my life over these things haha. when I my 96 tahoe needed one, I went to the dealer and just bought a brand new one full price before they discontinued it haha. to scared to touch it.

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iTrader: (5)

​​​​​​I still nightmare about these drive shafts haha. I got my first one at like 20 years old, knew almost nothing about cars.. the run around from shops telling me they don't know what it is, can't reproduce because we can't take it to 70, the speed limit is only 35.to telling me the rear end needed rebuilt, to having shafts built, balanced and always being junk. it might have been this site I caught a comment to find a v6 car shaft and put it in untouched. it was the first time in probably 15 years of owning that car thst I felt it smooth. ugh. they would only last a year or 2 before I'd have to find another one. manual and racing around was hard on them I guess haha.

dabomb6608

iTrader: (3)

I shot a text over to him asking if he had a spare one laying around. He said he didn't but would ask some of his buddies who have 4th gens as well. This is definitely not something that is "right" with the setup. It is far too bad of a vibration to be livable and just accept it. I might've been like that when I was in my early 20s first building the car but not anymore.

dabomb6608

iTrader: (3)

That is going to be a issue because I have to use a Ford C6 style yoke with the TKO 600. So no matter what that end of it would be getting a new conversion joint.

???

iTrader: (5)

I didn't realize. huh.

maybe leave the back alone? I've always though it was from where it goes into the pinion yoke anyways.

dabomb6608

iTrader: (3)

Had a spare moment while the wife was out this evening to back the car into her side of the garage and get the ski (Edit: Car lol you can tell I am in jetski work season) up on jacks in the rear. Front U-Joint feels tight. Rear U-Joint has some movement. Not "wiggle" movement but it looks like the caps held under the pinion straps that have inside C-clips aren't being held solidly. I can move the joint side to side about that axis a small amount and see at least one cap moves that amount under the strap. I am going to look into throwing a new joint in the rear to resolve the vibration. It is a factory steel shaft and a 9 bolt rear. I assume I need a 1310/3r joint?

???

iTrader: (5)

I have no clue on u joint so sizes, but yeah that doesn't sound right being able to move around.


you definitely have the most none 3rd Gen drive shaft in a 3rd Gen haha. c6 front skip yoke and a 9in rear. way out of my experience. I would hope the 9in joke would hold the u joint well thou when good?

dabomb6608

iTrader: (3)

It is the factory 9 bolt "Borg Warner" rear end. Not a 9 inch. I plan to one day upgrade to either a 8.8 or 9 inch. So the rear end side of the drive shaft should be factory setup. From searching I am coming up with a Spicer 5-3147X Joint being the correct one?

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iTrader: (5)

ohhhh haha. I missed 9 bolt.

I honestly still don't know the correct u joint. it's possible all those years thet sold me the wrong one anyways.

I hadn't changed a gm I joint at 20 plus years. I'll change Ford ones at work, but my own gm stuff, I treat drive shafts as disposable. I know you can't thou.

I do remember those stock joints being hard to get out.

dabomb6608

iTrader: (3)

Yeah, looks like if it is a factory joint it will need heat to melt the plastic used in factory. I honestly don't remember if all 4 caps had inside C clips or not when I was under it looking. Should've noted that while I was there.

I am also going to order a rear seal kit for the TKO transmission. Looks like there has been some leaking going on, torque arm had oil on it with some oil on the front joint/trans yoke as well. Wish I would've done all this over winter while it was all out.

???

iTrader: (5)

don't know if you've driven it enough to hurt. it back them I wiped out the tail. housing bushing on my t5 from the drive shaft all those years. but I put a ton it miles in mine with it. humming along.. probably 80k?

​​​​​​if the seal doesn't fix the leak, you might look into it.

dabomb6608

iTrader: (3)

Small update and this post is possibly relevant.

Installed the new u-joint at the rear end and put the new seal in the tailhousing of the TKO. One thing I noted while doing the work was my output shaft of the transmission does have some movement. More than I would expect. I am going to have to do some research to see how they are supported back there and figure out how much is too much.

I took it for a test drive and it has improved a little. below 70 it has little to no vibration. 75+ and it starts getting a heavy vibration and feels like it is definitely coming from the transmission end of the shaft. So need to look into that sooner than later.

Tom 400 CFI

How much movement is there w/the yoke installed? IMO, the tail shaft bushing and yoke should support the lateral loads on the end of the tail shaft. IDK about the TKO, but on the T5, the output shaft is unsupported for way too long/far, to manage those loads. The tail shaft bushing needs to do it.

dabomb6608

iTrader: (3)

I didn't measure it but it was enough I immediately thought it could be part of the problem. I watched a video of someone showing replacement steps and it is likely similar to the T5. Looked like the shaft had a solid foot of unsupported length that then is "supported" by the bushing in the tail housing. Unfortunately it looks like the transmission needs dropped for me to remove parts from the rear most cover on top to then allow removal of the tail housing. So it will likely get pushed to being a this winter project.

dabomb6608

iTrader: (3)

Still continuing to drive the car here and there. I don't even drive my personal truck that much anymore due to having a vehicle through work I drive M-F. So only time I ever really drive anything else is on weekends going into town. If it is me and the wife going we take the truck because it has AC and it has been the typical summer hot/humid the last few weekends. I did however talk her into taking the Trans Am when we went to the DMV Friday afternoon to get our "Real IDs" and addresses updated on licenses. Also got the plates up to date on the car while I was there. Hadn't been registered in over 4 years.

That drive was a good 30 minutes each way. With the return trip being on the interstate. Didn't notice any "new" issues that I wasn't already aware about. I am confident I will have to pull the transmission this winter in order to go check out the input and output shaft and get the bell housing alignment centered up. Vibrations have improved after doing the rear U-Joint but still have it above 75ish. Clearing up some of the vibrations has unmasked what I believe to be pilot bushing/input shaft vibration that is affected with high RPM.

Anyways the tune is slowly continuing progress. I had a post here https://www.thirdgen.org/forums/diy-...ual-trans.html where I have been playing with my AE settings.
Motor is definitely coming more and more alive. I am feeling confident enough in it that I will be adjusting my rev limiter on the MSD up from the conservative 5k it has been set at. Will be doing an oil change sooner than later as well. I've gone through one full tank of gas on it now. So still under 500 miles for sure since putting motor back in. I also plan to get a new Delco knock sensor as well as a heated o2 sensor to give closed loop tuning an attempt. I really think this setup could still handle running closed loop with the EBL. Also actively looking at new tire options. I think I am liking the General Tire G-Max RS, the tread looks very similar to the BFG G-Sport II I have on currently. They are available in the 245/50R16 that I believe is factory size for my car. Currently I run 255/50 in the rear and some odd ball in the front. Would love to still run the bigger tire in the rear but don't think it is available.

???

iTrader: (5)

I just read thru you tuning post. got me wondering about the lt4 knock sensor. those came factory with roller rockers. I seem to remember that the lt1 guys back then would put a lt4 knock sensor on theirs after they added roller rockers. it was said to be tuned for the noise?

for tires, I don't know your budget, but I've been looking for some for my other car, c6 with aftermarket rims in 18x10 and only thing in the size I need to keep the traction control happy is a toyo drag radial. I have never even seen one, but from reviews they seem a little less drag and more steet than the other major brands. so better in the rain and last longer? they have a 255/50/16 and a 275/45/16. interesting sizes.


glad you're able to have it registered and drive it a bit. I feel you on no ac thou haha.