Comp 980 vs 981

HalfDozIN

Member
Joined
Sep 7, 2021
Dusty Bradford was one of the guys I cut my teeth on and I read every post of his on here and asked him a ton of questions when he was here. I read a post of his a long time ago where he mentioned he was swapping valve springs several times a season cuz they softened up. I learned the hard way. I was up against a local and had him covered till half track and he walked around me. Valve springs had softened up and the RPM's flat lined. Took me a full year to get up beside him again...and I didn't make the same mistake.
I could see it happening for sure. It's like hitting a brick wall.
 

HalfDozIN

Member
Joined
Sep 7, 2021
When you experience this problem and notice that all of your power returns instantly when the trans shifts into the next gear, that is strong evidence that your valve springs are inadequate.
That's how I arrived here, because that is exactly what happens. About 90% throttle causes shifts right at 5000 and it never falls off. On the carpet shifts are at 5300, and it will just fall over dead until it shifts, and then pull hard again until the next time it reaches that rpm. When gaskets and valve seals arrive, I'll get it all changed out. Be a good end to the season by putting it up for winter working well.
 

GNONYX

Well-Known Member
Joined
Oct 16, 2009
What about Kirban, he claimed this set of 12 heavy-duty valve springs are the correct size but stronger (100 lb test) for 1984-1987 Turbo Regals. The maximum lift is 430 lbs.
What about NAPA's valve spring part #: SEP VS739R
 

Ttype6

Well-Known Member
Joined
Aug 17, 2004
What about Kirban, he claimed this set of 12 heavy-duty valve springs are the correct size but stronger (100 lb test) for 1984-1987 Turbo Regals. The maximum lift is 430 lbs.
What about NAPA's valve spring part #: SEP VS739R
Kirban's valve springs have been offered for many years. They are definitely one of the ways to skin this cat.
I don't know anything about the Napa springs, but if they fit and give you what you want for spring pressure, they will work.
 

Buick Mark

Active Member
Joined
Sep 12, 2001
Why would you said a rebuild is in order, when many TR member claimed after 35,000+ mileage the valve springs will need to be replace.
He said everything was buggered when he bought it, I'd pull the engine and check everything out, who knows what else is messed up.... Timing chain, cam??
 

liquidh8

Active Member
Joined
May 17, 2006
Following this thread. I had a very similar issue before I put the car away for the winter. I replaced the stocker with kirbans springs, new seals, HD shaft braces, etc, a few years back. Finally got to play with the car this year and it would nose over at 5k. 22lbs with 22/20 timing, alky and all the fuel it needs in the world verified by by WB and datalogs. Had a suspicion is was the springs, although they were new.

In an case, I'll be following to see how you make out, good luck and happy turkey day!
 

GNONYX

Well-Known Member
Joined
Oct 16, 2009
Update: I replaced the valve springs with Comp Cam:
Single Outer Valve Springs: 1.254" O.D., .880" I.D.SKU 981-12$59.95
7° Steel Retainers: 1.250" Spring Dia.SKU 742-12$55.95
12 Pairs Machined Steel Race Locks: 1 Groove, 7° Angle, 11/32" Stem SizeSKU 648-12$21.95
And a spray can of Comp Cam Valve Train Assembly SKU 106 $14.95
Some would say to used the original retainers and locks, but I personally would rather be safe than sorry for something to happen due to mismatch.
Right now I'm waiting for the rocker buttons retainers; as cheap as they are why not replace them, it's only been on the rocker arm for 34 years, or as for me 92,000 miles.
 

HalfDozIN

Member
Joined
Sep 7, 2021
Following this thread. I had a very similar issue before I put the car away for the winter. I replaced the stocker with kirbans springs, new seals, HD shaft braces, etc, a few years back. Finally got to play with the car this year and it would nose over at 5k. 22lbs with 22/20 timing, alky and all the fuel it needs in the world verified by by WB and datalogs. Had a suspicion is was the springs, although they were new.

In an case, I'll be following to see how you make out, good luck and happy turkey day!
That's where I'm at with 20*/18* at 17 psi. Plenty of fuel and no KR, just falls over. I didn't see the point in trying to push it any harder at the track without addressing the issue, so I haven't tried upping the boost, although I had the octane for it. I have the new springs, seals, gaskets, and a set of Weber rocker shaft braces, just crunched for time lately. New baby will be here any day, trying to get my ducks in a row for that. I will be sure to update this when I get it all swapped over. Thanks, and hope you have a good one too!

He said everything was buggered when he bought it, I'd pull the engine and check everything out, who knows what else is messed up.... Timing chain, cam??
Well, it's sure a fair statement to call a lot of their handiwork "buggered", like the vacuum brake source tee'd in with the pcv valve when I got the car. as far as the timing chain, I have just made the ASSumption that it was replaced with the cam. I am 100% positive the engine will be out of this car in the next few years, because I know me, but I have other irons on the fire at the moment. I have solid oil pressure, it doesn't run hot, good compression, etc. so it will do for now. If it doesn't, there's another 109 in the garage to be built. Not aiming for intentional destruction, but things do happen. The Extreme level 2 and electric brake looks good anyways, so that would be a good time for it.
 

liquidh8

Active Member
Joined
May 17, 2006
I was looking at those weber braces for the new 4.1 build, though if I can find a deal I'm going with rollers. Anyway, congrats on the upcoming gift and I'll check back soon when you update!
 

HalfDozIN

Member
Joined
Sep 7, 2021
Off Topic, but CONGRATULATIONS and best wishes for a Happy, Healthy Baby and MOM!!!
Would be a great Thanksgiving Present!!! :D

Good Luck & ENJOY!!!
Thank you for the kind words!
I was looking at those weber braces for the new 4.1 build, though if I can find a deal I'm going with rollers. Anyway, congrats on the upcoming gift and I'll check back soon when you update!
Thanks! I went with them because there are 6 instead of 4, not to say the rjc ones aren't just as good. Just a personal "makes me feel better" deal. I'd love to go roller but then I'd just have to go roller cam too and there goes the escalation train running away again lol
 

liquidh8

Active Member
Joined
May 17, 2006
Thank you for the kind words!

Thanks! I went with them because there are 6 instead of 4, not to say the rjc ones aren't just as good. Just a personal "makes me feel better" deal. I'd love to go roller but then I'd just have to go roller cam too and there goes the escalation train running away again lol
That's also why I like them, 6 instead of 4!
 
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