New valve springs, parts needed?

[Boostrules]

My valve covers have been leaking for a while so since I need to replace the valve cover gaskets I would like to replace the valve springs as well. I don't want to stress the original timing chain so I'm using Comp Cams 979-12 valve springs which are rated 80 lbs. seat pressure. It was also recommended that I replace the intake valve stem seals with Felpro SS72623. Anything else I should change while I have the valve covers off? Thanks in advance for your input.

 

[DeltaBravo]

I think...

You should just do the gaskets and call her dun! Like your signature states "garage queen". Why do you want to replace springs and valve seals? Is it running bad or worst than normal? Is it blowing blue smoke on start up? If not, I would just leave it alone...change oil as you have and take her out on a Sunday drive.

If it an't broke, don't fix it.

 

[NyBlankets]

My valve covers have been leaking for a while so since I need to replace the valve cover gaskets I would like to replace the valve springs as well. I don't want to stress the original timing chain so I'm using Comp Cams 979-12 valve springs which are rated 80 lbs. seat pressure. It was also recommended that I replace the intake valve stem seals with Felpro SS72623. Anything else I should change while I have the valve covers off? Thanks in advance for your input.

Do you have the part number for the exhaust side of the valve stem seals or are they the same part #?

 

[Boostrules]

I think...

You should just do the gaskets and call her dun! Like your signature states "garage queen". Why do you want to replace springs and valve seals? Is it running bad or worst than normal? Is it blowing blue smoke on start up? If not, I would just leave it alone...change oil as you have and take her out on a Sunday drive.

If it an't broke, don't fix it.

No smoke, runs well but I was hoping to improve the performance a bit. When I take her out I can't help but get into the throttle a bit. The parts are cheap enough & the springs are original. I'm sure the seat pressure has diminished quite a bit from sitting around during the winter months in one position.

 

[Boostrules]

Do you have the part number for the exhaust side of the valve stem seals or are they the same part #?

It seams that the exhaust valves stem seals can't be replaced. They are an integral part of the heads.

 

[DeltaBravo]

No smoke, runs well but I was hoping to improve the performance a bit. When I take her out I can't help but get into the throttle a bit. The parts are cheap enough & the springs are original. I'm sure the seat pressure has diminished quite a bit from sitting around during the winter months in one position.

More performance= bolt on's...assuming everything else is healthy. Turbo upgrade, injectors, chip, exhaust...will really wake that beauty "garage queen" up.

 

[DeltaBravo]

all I am trying to say is: your OE valve springs are probably fine and will remain fine for a while. It becomes an issue when you demand more RPM's from the OEM's standard.

 

[ScottHeidinger]

If you've already got comp 979's installed I wouldn't put stiffer springs in. With oil today you really need to convert to a roller cam if you want to upgrade. Heavy springs and a flat tappet cam could cost you your engine and it's just not worth it. If you had original springs and wanted to put in some 979 or 980's that would make sense but unless those 979's are old and worn out or improperly installed I wouldn't change them.


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[dank GN]

First I would get comp 981 . And as far as your original plastic tooth timing set I would change it out before it goes out while driving for a double roller or ta makes a single chain I've heard good things about . 80 lbs on the seat is nothing u will lose around 10 pounds after the first heat cycle giving u less then worn stock springs . I have pulled out 980 with 80ish seat pressure . Spring pressure is your friend and 100 would be the minimum I would even think of putting on the seat

 

[Boostrules]

If you've already got comp 979's installed I wouldn't put stiffer springs in. With oil today you really need to convert to a roller cam if you want to upgrade. Heavy springs and a flat tappet cam could cost you your engine and it's just not worth it. If you had original springs and wanted to put in some 979 or 980's that would make sense but unless those 979's are old and worn out or improperly installed I wouldn't change them.


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That's exactly my situation, Original springs that have sat in 1 position for months at a time during the winters when I don't drive her. I was worried that the 980's or Kirbans would have too much pressure, that's why I was thinking the 979's because the originals were rated at 80 lbs. I don't want to hurt something (cam, timing chain) & if slight gain in response isn't worth the risk & work I won't do it.

 

[Boostrules]

all I am trying to say is: your OE valve springs are probably fine and will remain fine for a while. It becomes an issue when you demand more RPM's from the OEM's standard.

I thought while I was in there anyway I would replace the 30 year old originals with a same rated spring (979's). If you guys feel that the slight gains aren't worth the risks to the timing chain or cam then I'll skip the extra work. If & when I upgrade the turbo, boost etc. I'll consider a roller cam as part of those upgrades. I do enjoy getting on her a bit & lighting up the tires on a roll or chirping second gear with just a little extra throttle right before the shift but I just want a fun street car.

 

[dank GN]

Agian those stock plastic teeth timing chains are way over due to get swapped out . 30yrs old and if your worried about your springs sitting I wonder what your stock gear looks like . On the pressure it's not a response thing you will incur valve float at lower Rpms and it will feel like it just doesn't accelerate kind like falling on its face . You also have to remember with boosted motors the boost psi is directly pushing on the valve so 14psi on your 1.7" intake valve . So after the first heat cycle they will have 70ish on the seat then in boost you are 58 psi on the seat . I'm sure you r going to find out after u put them in and the next post is it stumbles on the top end and isn't accelerating . All this to save a $100 and a 30 yr timing chain . Get some 981 and a timing chain . The cam and lifter and rockers will handle the little extra set pressure no problem .

 

[Boostrules]

Agian those stock plastic teeth timing chains are way over due to get swapped out . 30yrs old and if your worried about your springs sitting I wonder what your stock gear looks like . On the pressure it's not a response thing you will incur valve float at lower Rpms and it will feel like it just doesn't accelerate kind like falling on its face . You also have to remember with boosted motors the boost psi is directly pushing on the valve so 14psi on your 1.7" intake valve . So after the first heat cycle they will have 70ish on the seat then in boost you are 58 psi on the seat . I'm sure you r going to find out after u put them in and the next post is it stumbles on the top end and isn't accelerating . All this to save a $100 and a 30 yr timing chain . Get some 981 and a timing chain . The cam and lifter and rockers will handle the little extra set pressure no problem .

All right, I think you guys have convinced me. The springs, I felt up to the task of doing but the timing chain sounds a bit more involved then I feel comfortable with. What kind of $ should I expect to pay for labor to replace both chain & springs?

 

[dank GN]

It's not that bad actually . I think doing springs with the head on is Alil harder personally . http://www.gnttype.org/techarea/engine/tchain.html

 

[earlbrown]

Listen to DankGN.


You needed to replace that timing set yesterday. At this point mileage means nothing, It's all about the years at this point.


With valve springs, EVERY GN needs valve spings, period. If you hop into my time machine and go back to 1987, buy a brand new GN and test the springs... they will be too weak (much like the fuel pump wiring).