1978 Oldsmobile Cutlass Supreme LQ4 + 4L80E swap
08-09-2016, 02:21 AM
#121
Today's passenger was my fluffy buddy Duncan. Drove the car 190 miles round trip to pick him up and used slight less than 3/4 of a tank. The car ran so well. Only hiccup is sustained high-load, low throttle up hill results in a very very over-rich condition and the car wants to die. Can't see why in the logs.
08-17-2016, 03:36 PM
#124
Turns out it was a loose exhaust rocker rocker. Probably beat up the lifter a big and I'm sure the piston didn't like the increased pressure and heat. Pushrod look good and is straight, rocker is fine, threads in head are ok. I just tightened it back to spec and viola, all fixed.
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08-18-2016, 05:28 PM
#127
Exactly. And it was on my list of things to check, but it sure sounded like a rod knock to me! Must have been the cylinder trying to run with the exhaust valve closed. And the big plastic intake makes EVERYTHING so much louder. Giant amplifying speaker. Probably on my way to prematurely dead bearings on the cylinder now...
08-22-2016, 02:51 AM
#129
Replaced my solid UMI lower control arms with a pair of adjustable ones with the roto-joint on both ends. Super nice piece. R&R, torqued and lubed in under an hour. Also spent some time touching up the millions of rock chips in the paint. Looks terrible, but better. No pictures of either, I was in a hurry. Also working on getting the car to return to idle better and not surge. Getting there, but it's slow going. Just when I think I have it just right, I get a surge or a stall. Taking it to Bremerton Raceway first weekend of September. Three days of no-prep, no time drags and roll racing with street cars. Wish it was timed, but it should be a good three days of testing and tuning.
08-22-2016, 12:11 PM
#130
I'm glad you figured the noise out. How do you like the Circle D converter? Does it drive like a stock converter with moderate throttle? I'd appreciate it if you could post some vids....I have the same unit but won't have a chance to test it until next Spring.
08-22-2016, 01:26 PM
#131
It's absolutely amazing. Light throttle acceleration from a stop ends up in the 1,800 to 2,000 rpm range. 50% throttle gets it to flash pretty high. WOT on mine is an instant 4,000rpm. I'll try to get some vids when I'm out tuning again.
08-23-2016, 05:37 PM
#132
I was out tuning my car trying to smooth out a return to idle problem I've been having. I like to do this in a grocery store parking lot near where I live. While I'm analyzing my last log to see what needs adjusting, a Chevy pickup pulls into the spot next to me. My car is thumping away at idle and the passenger in the truck yells to me, "is that thing a hybrid?". I haven't spontaneously laughed that hard in a long time.
Oh, and I forgot to get video. Would have been a perfect time to show how good the converter works. Here are some log snapshots.
Leaving normal from a stoplight....or maybe a parking lot. 13-17% tps, 2,000-2,200rpm.
I gave it more than normal throttle at 17mph and got it to get near 3,000rpm. Progressively feeding more throttle makes the rpm rise linearly.
On another log, I gave it a good smash at 10mph and it flashed to 3,900-4,000 rpm instantly.
Oh, and I forgot to get video. Would have been a perfect time to show how good the converter works. Here are some log snapshots.
Leaving normal from a stoplight....or maybe a parking lot. 13-17% tps, 2,000-2,200rpm.
I gave it more than normal throttle at 17mph and got it to get near 3,000rpm. Progressively feeding more throttle makes the rpm rise linearly.
On another log, I gave it a good smash at 10mph and it flashed to 3,900-4,000 rpm instantly.
08-31-2016, 11:34 PM
#138
Last week I noticed a small puff of blue smoke from the passenger side every time I stopped. After a bit, it would go away. Figured it might just be a bad valve seal. Then I've been having trouble chasing my tail getting airflow and fueling at idle and especially returning to idle/coming off throttle to be reliable. Thought it was time to pull the covers and maybe look at the seals or perhaps put some sealant on the rocker arm bolts. I found a problem:
That guy has been sitting there like that for a while I suspect. The retainer lock is a bit damaged, but it should be good for the weekend. It's a fatigue crack and failure and valve drop waiting to happen.
Rocker survived, pushrod has some cosmetic wear where it rested on the cylinder head, but it is straight as an arrow and the ends are fine. When the pushrod slipped the cup, the lifter went into the retainer and stayed there which is why I didn't have any noise. The cylinder was just pumping oil into the exhaust system.
Tonight I went through the passenger rockers, one by one and removed, cleaned, applied loctite and re-torqued being absolutely certain I was on the base circle of the cam. Got dark, so I will do the other side tomorrow. Fired up to check and everything seems honky-dory.
That guy has been sitting there like that for a while I suspect. The retainer lock is a bit damaged, but it should be good for the weekend. It's a fatigue crack and failure and valve drop waiting to happen.
Rocker survived, pushrod has some cosmetic wear where it rested on the cylinder head, but it is straight as an arrow and the ends are fine. When the pushrod slipped the cup, the lifter went into the retainer and stayed there which is why I didn't have any noise. The cylinder was just pumping oil into the exhaust system.
Tonight I went through the passenger rockers, one by one and removed, cleaned, applied loctite and re-torqued being absolutely certain I was on the base circle of the cam. Got dark, so I will do the other side tomorrow. Fired up to check and everything seems honky-dory.
Last edited by 1970camaroRS; 09-01-2016 at 02:25 PM.
