Dump the gear and go timing chain?

[2GNS4ME]

Hi Guys,

New to stage II and I picked up a car with a stage II shortblock that is out of the car. The motor was done at a reputable shop here in Chicago and my question is if I should keep the gear setup or go timing chain. The car will rarely see track time. Gear setup is already in and supposely dialed in and ready to go. Should I dump it and replace for a timing chain setup for street car? Im excited to get the car running. I still have to order lifters which ones do I go with? I have to look but I believe the cam is a 218/212 roller cam and it came with brand new gn1r aluminum heads.



thanks
2gns4me

 

[Squid4life]

Hydraulic roller I assume? I think a lot of the decision between gear drive and chain was based on valvespring pressures and how often you plan to preventive maintenance the motor. (also, how much you plan to drive the car) Some guys are having the chains stretch and are changing them frequently. Other guys say the gear drives create nasty harmonics.

I would answer how often/how many miles you plan to put on it, whether it is solid or hydraulic roller, and valvespring pressure if you can get it. Also, are you running a stock ECM or something like FAST XFI. Sometimes you hear about the harmonics messing with the knock sensor at certain RPMs. After you post up that info, you should get more bites from the guys more versed in this area.

 

[WIKEDV6]

Well Denny, the simple thing to do is go with the chain as it's less complicated. Your car is a street car with 224/224 Hydraulic roller and you are not looking to light the world on fire. I think the springs on your GN1R heads are like 140-160lbs at the seat. The chain would work just fine. The only reason for keeping the gear drive is that it's already installed on your motor and according to the previous owner; he had no issues with it. I heard stories about people breaking chains and loosing their whole engines. Those guys run solid roller cam with close to 500lbs seat pressure springs. Some people say they are noisy as well. I am going with gear drive on my stage II with solid roller cam so we will see.

Make sure you buy a good brand double roller chain that don't stretch as easily and go with it.

HTH
Prasad

 

[2GNS4ME]

Thanks Prasad for the correction. Hmm things to think about!!

 

[2GNS4ME]

Thought I would update the thread with the current gear drive setup I have and modified cover. Talked to the old owner. He said that he never had a problem on the streets with this setup and it was quite.

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[Squid4life]

If it were me, I'd run it since it is already there. If not, order one of the new chains from TA performance that Nick Micale has been testing. He is one who saw a lot of stretch and breakage from some other model chains, and worked with TA to get it done right. There is a thread on the site about them.

 

[2GNS4ME]

I agree most are saying to run with the gear drive setup. The only issue some brought up if the bolts come loose that hold the gear drive together I can have major issues.

I was looking at the thread of the TA timing chain if I go that route I would order from them for sure.

 

[jlat]

hello people's: I'm with going with the gear set since it's in. I've never heard a engine in a TB run with timing gears but I knew a guy who has a set in his V8 pickup and it sounded like he had a blower in it the way it wined.
IBBY

 

[JayC]

Id get rid of it. Ive had gear drives fail. Its not pretty.

 

[Squid4life]

I agree most are saying to run with the gear drive setup. The only issue some brought up if the bolts come loose that hold the gear drive together I can have major issues.

I was looking at the thread of the TA timing chain if I go that route I would order from them for sure.

It is 50/50 to be honest. A broken gear drive will do a bunch of damage, and so will a broken chain. If concerned about bolts coming loose, use red loctite. Either way you go, if you ran a lot of spring pressure (which sounds like you are not) I would be prepared to pull the pan and/or front cover after a few thousand miles to make sure all is well, then maybe again another 5-8k miles. Or, with the low spring pressures, pull the front cover or pan after 10k if using the chain. I think maybe the TA chain would be the safest route overall. Nick is doing testing and it seems to be an improved piece. If the chain broke, hopefully you would get lucky and the valves would not be at full lift and make contact with a piston??? If the chain breaks, there may be less parts to be rattling around the bottom of the engine, whereas the gear drive may shed more teeth?

Not really speaking from experience, just playing the "what if" game.


jlat, the gear drive you are probably talking about was a Pete Jackson or similar maker. You could actually order them "Noisy" so they would sound like that. Nothing like going to the street races and seeing a mid-14 second car sound like it was fast with one of those. :biggrin:

 

[JayC]

Red Loctite will not keep the bolts in. Its harmonic vibrations that cause them to come loose. We even tried green Loctite with no luck there either.

Go with a chain. You'll be much happier in the end.

On a side note, you might have a gear drive that will hold up. I know some Buick vendors made their own but the ones Milodon and others put out are very prone to backing the bolts out and bringing a sad end to your day.

 

[Squid4life]

Red Loctite will not keep the bolts in. Its harmonic vibrations that cause them to come loose. We even tried green Loctite with no luck there either.

Go with a chain. You'll be much happier in the end.

On a side note, you might have a gear drive that will hold up. I know some Buick vendors made their own but the ones Milodon and others put out are very prone to backing the bolts out and bringing a sad end to your day.

Good info, thanks for sharing Jay! Like I said, not much experience with it, just thinking out loud, so thanks for the info. Much rather have a good experience than a bad ($$$$$) one.

 

[JayC]

Im sure there will be people come in here going "I have a gear drive and its awesome!" and like I said, there are a few good units out there but most people are recycling the old stuff thats out there (I dont think any big company currently makes a V6 gear drive anymore) and you're just asking for it. Id rather replace a chain once a season than deal with the carnage of a broken gear drive. We had one come loose mid pass and took out two turbos, a set of heads, a piston and the gear drive itself.

Valvetrain stopped moving, piston hit valve, knocked the head off the valve, knocked the seat loose from the head, beat the crap out of the combustion chamber, spit pieces back into the intake which went out a cylinder on the other side and put pieces into both turbos.

Found the idler gear for the gear drive intact with the bolts in the oil pan.

Awesome

 

[Squid4life]

Yikes! That would mean a parked car for a very long time for me... Do you think spring pressures play a part into the carnage/possible carnage, and the decision whether you should run chain or gear at a certain level? Just curious if there is a "level" of spring pressure that would make one choose one way or another with chain or gear?

 

[2GNS4ME]

Thanks Squid and Jay for your input. Now Im confused I have 2 months to decide since the car is going in for paint. I have a bad ass motor with limited experience. Just want to make sure I put the right stuff on the motor.

 

[JayC]

Yikes! That would mean a parked car for a very long time for me... Do you think spring pressures play a part into the carnage/possible carnage, and the decision whether you should run chain or gear at a certain level? Just curious if there is a "level" of spring pressure that would make one choose one way or another with chain or gear?

I dont think spring pressure has anything to do with it. I had a long talk with Jim Ruggles a long time ago about gear drives and he was the one who initially told me to get rid of it. He said they had had issues in the Busch series with gear drives coming loose due to engine harmonics and thats pretty much what we found as well.

Nothing is indestructible. On Nelson Hernandez's engine (Way back in the 90s) we started with a gear drive. Thats the one that came loose and wrecked the engine. We switched it to a timing chain and I would be willing to bet the car had 150 more HARD passes on it with minimal chain stretch. Same chain is still on the engine but the engine is sitting in one of Shane's storage facilities. One of these days I'll get around to putting it in Spooky.

 

[Nick Micale]

....... The chain would work just fine. The only reason for keeping the gear drive is that it's already installed on your motor and according to the previous owner; he had no issues with it. I heard stories about people breaking chains and loosing their whole engines. Those guys run solid roller cam with close to 500lbs seat pressure springs........Prasad

I agree a chain would be fine in this situation.

The gear set-ups I know of personally do make more noise, but I would be concerned about proper lubrication of the gears.

With lots of street driving, the gears and bushings will wear quickly if they do not receive adequate oil. We even do mods with a chain to spray it with oil for cooling, as well as lubrication.

As far as 500# seat pressures, I do not know of any turbo Buick pressures that high even in the 7 sec. builds. :biggrin:

 

[Squid4life]

Thanks Squid and Jay for your input. Now Im confused

Yeah, me too... :biggrin: I always though gear drive was best, most stable, etc, and was happy because I have a nice new one to use. Now, I am wondering if the TA chain is not a better idea... My car will be a sick driver, with Stage 2 heads and a solid roller cam. The spring pressures will still be pretty high, hence my pressure question above...

Dang decisions...

 

[Nick Micale]

Yeah, me too... :biggrin:..... My car will be a sick driver, with Stage 2 heads and a solid roller cam. The spring pressures will still be pretty high................

Why do you want high spring pressures for a street car, you do not need them very high?

I can take my engine above 8000 RPM with 240# on the seat.

You need to filter the BS on the internet from the "armchair" experts, and the ones that have actually built, driven and raced their cars.

Jay and I have been in the "trenches" for a long while, and LOTS of broken parts have been a big part of our learning experience.

 

[Squid4life]

Why do you want high spring pressures for a street car, you do not need them very high?

I can take my engine above 8000 RPM with 240# on the seat.

No, i do not want high spring pressures, just aware S2 heads with a large solid roller will require more tham the typical 204/214 flat tappet. I have not reached the point of figuring required pressures yet, but trying to take all aspects of the equation into account. That is why i am asking questions of the "trench" guys so i dont waste a bunch of $$$$$$$. Thanks again guys!