I assume my 86 GN has the original timing chain and valve springs, and after researching many posts on this site many suggest replacing these two items. Any suggestions on timing chain? How do I choose the correct LB test on valve springs? I plan to do quite a bit of modding down the road so I'm looking for a scaleable solution. Thanks!
Timing Chain/Valve Springs
- Thread starter mtbraun
- Start date
scojack_2001
Livin' Like A Refugee
- Joined
- May 24, 2001
I put a Edelbrock double roller chain in my car back in February of '08 and no problems since. Did a bunch of other stuff too while it was all apart.
The valvesprings depend on what you're future upgrades will be. If you going to keep the stock heads/cam for now, I'd put a set of Comp 980s in it and call it a day. When/if you upgrade the top end of the motor you'll have to change them. But the 980s are only $40 a set here so its not bad.
Hope this helps.
The valvesprings depend on what you're future upgrades will be. If you going to keep the stock heads/cam for now, I'd put a set of Comp 980s in it and call it a day. When/if you upgrade the top end of the motor you'll have to change them. But the 980s are only $40 a set here so its not bad.
Hope this helps.
Do you happen to know the edelbrock part #? Am having a hard time finding the right one. Thx.
scojack_2001
Livin' Like A Refugee
- Joined
- May 24, 2001
Straight from Edelbrock's website. Maybe one of the vendor's will have a similar/better part. You should be able to find the Edelbrock just about anywhere. I found mine locally.
V6 183, 196, 231, Turbo, 252 w/ integral distributor drive 1977-88 #7829
- Joined
- May 26, 2001
The problem with the double roller replacement timing sets in that price range is they all use a cast cam gear which wears very fast. Within 3-5000 miles there will be a lots of chain stretch, and you cannot use a chain tensioner with a double roller. :frown:
The less expensive sets are even worse in their longevity. This is not an opinion, as I have installed and replaced hundreds of these Buick chain sets over the past 25 years.
You do have 2 other options, one like the Cloyes, and other brands of double roller sets that use a billet cam gear. The other option is a TA set less expensive than the double roller type which does use billet gears and a silent chain where you can use a tensioner.
As far as changing valve springs, with most of the stock replacements I have seen and experienced, it is a waste of time and $$$ unless you are upgrading for more performance. This is not a maintaince item like the chain.
If you are going to do mods in the future, that is the time to determine if to do it, and exactly which spring to choose.
The problem with the double roller replacement timing sets in that price range is they all use a cast cam gear which wears very fast. Within 3-5000 miles there will be a lots of chain stretch, and you cannot use a chain tensioner with a double roller. :frown:
The less expensive sets are even worse in their longevity. This is not an opinion, as I have installed and replaced hundreds of these Buick chain sets over the past 25 years.
You do have 2 other options, one like the Cloyes, and other brands of double roller sets that use a billet cam gear. The other option is a TA set less expensive than the double roller type which does use billet gears and a silent chain where you can use a tensioner.
As far as changing valve springs, with most of the stock replacements I have seen and experienced, it is a waste of time and $$$ unless you are upgrading for more performance. This is not a maintaince item like the chain.
If you are going to do mods in the future, that is the time to determine if to do it, and exactly which spring to choose.
Thanks for the info - didn't know that. I'm not about to skimp on something that important. Do all Cloyes chains have a billet cam gear? I found one on Kirban's but it doesn't say for sure.
85begalttype
just a v6
- Joined
- Oct 22, 2008
the chain would eat into the tensioner and tear the tensionor apart
TR Custom Parts
Mark Hueffman - Owner
- Joined
- May 25, 2001
At what point would you consider replacing the timing chain. Is it strictly by mileage? My GN motor has never been opened up except for changing the valve covers and replacing a leaky rear main seal at 4700 miles. Now has 34,000 miles
I've always heard 50k-70k miles but no more. Never heard of age being a factor though. The stock gears are nylon though and not very strong under power, even with stock cam and springs. And who wants even small pieces of nylon going through their oil system? I suppose you use your nice oil filter though so it's probably not much of a worry.
FWIW, I've used the Cloyes since march '08 and 45k miles without issue. I even reused it when the Erson went in last year, but the T/A unit with tensioner sounds like the best answer.
I used a Melling OEM replacement timing set wit no issues. It was the replacement of choice back in the late 90's. 30k+ miles and 8 years later it still looked like brand new with no signs of slop when I took my motor apart. As far as valve springs go, I thought that the stock ones were weak and wore easily. Mine were floating bad when I first goy my car with 85K or so on it. All I had was 36lb injectors, intake, chip, exhaust, and fuel system mods running high 12's. I swapped the valve springs to LT1 springs (I think) and gained 3 tenths. Unfortunately the springs were too much for the cam and it wiped the #3 exhaust lobe over about 2 years. I replaced it with a Melling OEM cam and lifter set. I went over 20k miles on that. When I pulled the motor, I mic'd the cam and had no signs of wear.
I got mine when I bought the car and was told they were LT1 springs. They may have not been. Of course me running Mobil1 synthetic through the car (lack of ZDDP) could have been the issue as I switched to Dino oil after swapping the cam and the same springs never hurt the Melling. Do you remember if the LT1's are taller than the OEM ones? I remember mine were.
That's what I remember. Stock steel replacement gear with stock style tensioner was good for a motor down into the 10s. Lt1 springs are rated a tad too high seat pressure, seems like it was around 110lbs. Stock calls for something like 75-85lbs may not be exact, but the comp 980s are something like 85. I took the internal dampener out of the 980s and then used the stock seat cups which put the seat pressure around 82 or so. There is an old thread about this with all the specific details of the exact seat pressures. I've ran this setup now for about 10 years with no probs and very consistant times in the low to mid 7s in 8th and 11s in qtr. Yeah seat pressure of my stockers at 50k miles were about 50lbs at install height.
If this is your first time doing valve springs or Timing chain on a Buick, I would suggest you break it up into two separate jobs.
There is almost no synergy between a valve spring swap and a timing chain swap. Do the valve spring job 100%, then if you feel up to it, do the timing chain, but don't do both at once, especially if the car is something you need to drive.
I've did the "combo" the first time I did both and it made for a very long day. After that first one, though, you learn all the tricks and the second one is pretty easy. I recommend practicing on a friends car.
There is almost no synergy between a valve spring swap and a timing chain swap. Do the valve spring job 100%, then if you feel up to it, do the timing chain, but don't do both at once, especially if the car is something you need to drive.
I've did the "combo" the first time I did both and it made for a very long day. After that first one, though, you learn all the tricks and the second one is pretty easy. I recommend practicing on a friends car.
The problem with the double roller replacement timing sets in that price range is they all use a cast cam gear which wears very fast. Within 3-5000 miles there will be a lots of chain stretch, and you cannot use a chain tensioner with a double roller. :frown:
The less expensive sets are even worse in their longevity. This is not an opinion, as I have installed and replaced hundreds of these Buick chain sets over the past 25 years.
You do have 2 other options, one like the Cloyes, and other brands of double roller sets that use a billet cam gear. The other option is a TA set less expensive than the double roller type which does use billet gears and a silent chain where you can use a tensioner.
As far as changing valve springs, with most of the stock replacements I have seen and experienced, it is a waste of time and $$$ unless you are upgrading for more performance. This is not a maintaince item like the chain.
If you are going to do mods in the future, that is the time to determine if to do it, and exactly which spring to choose.
Nick - the Cloyes website does not cross reference a timing chain set part number for the Engine code 7. Only A. Are they they same timing chain? Also, it doesn't specify whether or not the cam gear is billet or cast. Are all Cloyes cam gears billet? Also my NAPA guy is showing three variations of the chain set - "original" and two other options for reduced center distance (.0005, .0010). My motor is bone stock so I assume I would need the "standard" center distance, as long as I can find one with a billet gear.
GNONYX
Well-Known Member
- Joined
- Oct 16, 2009
- Joined
- May 26, 2001
The cast gears are cheap in price and quality, and the inexpensive sets come from off-shore factories. Cast gears wear quickly and that is one reason why the chains become loose.
A quality chain is much stronger and will stretch less, while the billet machined gears last longer as well.
Cloyes is working on a billet gear timing set for the Buick application, but has not pushed production due the small market for it.
A cheap off-shore timing set can be as low as $30, and a quality billet will be $100 more. There are also sets in between these price extremes that will work well depending upon application.
Check with your favorite turbo Buick vendor, as many stock the various timing sets.
