921 Vs. 978 Comp springs????
Thread Starter
Instructor
Joined: Sep 2003
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From: Friendswood TX
921 Vs. 978 Comp springs????
I purchased a set , so i was told... of 921 comp valve springs. The springs are said to have only 3000 miles on them. I picked them up at a good price.
When they finally arrived 3 weeks later the box on the outside had a part number of 978-16. So I emailed him the obvious question. Again replies that they are indeed 921's. These things look like coil springs off of a Pinto. 921's are supposed to fit in the stock spring seat. These don't even come close. Now to the questions.
1. Is there something I am missing? Are special spring seats or cups to be used with these springs?
2. What is the O.D. of the 978 and the 921?
I know 978's need the spring pockets cut. I was really trying to avoid that. That is why i purchased the 921's. I have looked on Comps web site and they give very little info on LS1 springs. I have pretty much looked everywhere. I don't want to take my new heads to the builder for assembly with the wrong springs. Any help would be great.
Thanks, Shane
:chevy
When they finally arrived 3 weeks later the box on the outside had a part number of 978-16. So I emailed him the obvious question. Again replies that they are indeed 921's. These things look like coil springs off of a Pinto. 921's are supposed to fit in the stock spring seat. These don't even come close. Now to the questions.
1. Is there something I am missing? Are special spring seats or cups to be used with these springs?
2. What is the O.D. of the 978 and the 921?
I know 978's need the spring pockets cut. I was really trying to avoid that. That is why i purchased the 921's. I have looked on Comps web site and they give very little info on LS1 springs. I have pretty much looked everywhere. I don't want to take my new heads to the builder for assembly with the wrong springs. Any help would be great.
Thanks, Shane
:chevy
Thread Starter
Instructor
Joined: Sep 2003
Posts: 119
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From: Friendswood TX
Re: 921 Vs. 978 Comp springs???? (WideopenC5)
Come on guys. I have watched this web site almost every night for the last 9 months or so. There is a lot of know how on this forum. Some of the stuff you guys rattle off is very interesting. This should be a cake walk. :yesnod: Even if I don't get the right answser this forum still rocks. :thumbs:
Drifting
Joined: May 2003
Posts: 1,715
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From: cAshburn VA
Re: 921 Vs. 978 Comp springs???? (WideopenC5)
I just had 921s put in my heads before putting them back on. The 918s fit stock seats, the 921s do not, however with the correct seats they do fit the stock heads without having to machine the heads. I don't have the specs on the springs, but you can always call CompCams cam help line, they should be able to help you identify what you have. I suspect someone might have went from 921s to 978s and sent you the 921s in the new box maybe? Just a guess. I went with the whole 26921-kit, which included the hardened seats, titanium retainers and new valve locks, went on the stock heads and valves no problemo.
Good luck! :thumbs:
Good luck! :thumbs:
Le Mans Master
Joined: Jul 2002
Posts: 7,370
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From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Re: 921 Vs. 978 Comp springs???? (WideopenC5)
I have 978 springs and they are a dual spring that will not fit the spring pocket without cutting, they also require seats and retainers.
I also just checked Thuder racing's website and they show the 921 as a dual spring capable of supporting .650 lift http://www.thunderracing.com/catalog...vid=7&pcid=109
I also just checked Thuder racing's website and they show the 921 as a dual spring capable of supporting .650 lift http://www.thunderracing.com/catalog...vid=7&pcid=109
Le Mans Master
Joined: Apr 1999
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From: Burlington ON
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Re: 921 Vs. 978 Comp springs???? (runamuk)
Ask the guy you bought them off of when he put these 3000 miles on the springs. Comp 921 springs have not been out that long at all so he would have had to do quite a bit of driving to put that many miles on them since they were released.
I do have to agree that is is a very bad idea purchasing used valvesprings.
I do have to agree that is is a very bad idea purchasing used valvesprings.
Thread Starter
Instructor
Joined: Sep 2003
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From: Friendswood TX
Re: 921 Vs. 978 Comp springs???? (speedjohnson)
Do not buy used valve springs...ever.
It's a really stupid idea and I've got the busted stuff to prove it. sj
It's a really stupid idea and I've got the busted stuff to prove it. sj
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Melting Slicks
Joined: Oct 2002
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Re: 921 Vs. 978 Comp springs???? (WideopenC5)
SJ was just trying to point out that he made the mistake before and it would probably be best to order the springs new from comp the savings can't be that much used since they are not that much new (compared to most mods) and matt is just pointing out from our experience that there are people out there that have duped us all--everyone is more concerned with your not messing up your car and no one would waste their breath on this forum just to insult you--I have used many sets of valve springs and I can't remember the diameter on any of them--I used comp 918's for a while and I wouldn't **** on them if they were on fire I was breaking them and replacing them everytime I turned around-next time I replace mine it will be with isky golds--I am using crane duals now and they seem very good and come with their own mounting cup so no head work required.
Thread Starter
Instructor
Joined: Sep 2003
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From: Friendswood TX
Re: 921 Vs. 978 Comp springs???? (NEPTUNEBILL)
Everyone is always after that killer deal. Just thought I found mine. The cheapest kit that I have been able to find is around 550.00. I just went back through my emails. I was mistaken there is only 1500 miles on them.
I know they are still used. But 75.00 looked a lot better than 465.00 from Comp just for the springs. 918's are cheap. But I will be over .600 lift. Any how....thanks for your input. Maybe I will try and re sell them. I just can't imagine that this springs can be bad.
I know they are still used. But 75.00 looked a lot better than 465.00 from Comp just for the springs. 918's are cheap. But I will be over .600 lift. Any how....thanks for your input. Maybe I will try and re sell them. I just can't imagine that this springs can be bad.
Le Mans Master
Joined: Jul 2002
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From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Re: 921 Vs. 978 Comp springs???? (WideopenC5)
Maybe I will try and re sell them. I just can't imagine that this springs can be bad.
The machine shop will be checking the spring pressure
Drifting
Joined: Jan 2003
Posts: 1,809
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From: ST LOUIS MO
Re: 921 Vs. 978 Comp springs???? (WideopenC5)
I just bought a 921 kit form spped inc for $569. Springs, titanium retainers, seats, and valve seals. The 987's have a bigger inside diameter than the 921's I can barely get my pinky tip inside the 921's and the 987 I can easily get it in there. Scientific measurements for ya, huh. :cheers:
Thread Starter
Instructor
Joined: Sep 2003
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From: Friendswood TX
Re: 921 Vs. 978 Comp springs???? (brrymnvette)
I just got off the phone with Comp Cams. The old saying is true once again.
You cant trust anyone but yourself. The springs I bought are indeed 978's. I paid 75 plus shipping for a set of springs that would only cost 129.00 straight from Comp. If I cant get the problem resolved through email or by breaking legs I will let you guys know. I believe this guy is also member of this forum. I will give him a few days to fix this mess. If not, I will release his name so the rest of you can avoid this guy.
I guess this is some what of a cheap lesson learned. Thanks to all that have tried to help me out with the matter. :seeya
You cant trust anyone but yourself. The springs I bought are indeed 978's. I paid 75 plus shipping for a set of springs that would only cost 129.00 straight from Comp. If I cant get the problem resolved through email or by breaking legs I will let you guys know. I believe this guy is also member of this forum. I will give him a few days to fix this mess. If not, I will release his name so the rest of you can avoid this guy.
I guess this is some what of a cheap lesson learned. Thanks to all that have tried to help me out with the matter. :seeya
