I just broke my second MTI valve spring. A few years ago I broke #1 intake, this time it's #3 exhaust. Last time, MTI had some springs in stock and they sent me a free replacement. This time they very politely said they didn't have any more LT1 springs in the shop. (I'm sure they're Comp parts or something anyway, I doubt they make their own.)

Anyhow they suggested I just replace them all since I'm having issues with them.

I'm running a CC305, w/1.6RR's (so .544 lift). I have a Hydra-rev kit (if that matters). LT4 intake/heads. Stock push rods. Stock lifters.

I really don't want to be mucking with the seats (I don't have time or the tools), so something that'll fit without modification is necessary. Any recommendations on something that has a good track record on that sort of lift?

 

I'm not familiar with the MTI springs at all. Beehives would be a good choice tho. I dont think they require any work to make them fit and they are good to .600 lift. I have read a few posts tho of some people having trouble with the beehives cracking. But I think it was due to a few bad batches of the springs being sent out. Havent heard anything about it recently.

 

http://web.camaross.com/forums/showt...hlight=Beehive

Thats the thread discussing the beehive batch failures...

 

Look into PAC springs. Just Google it and they'll pop up. Get the behives that they offer and the issues mentioned in the post above shouldn't be an issue.

 

For the PAC's what part number would it be, the 1218's? They list all the parts as LS1 on their website and I have no idea if the LS1/LT1 use the same seats/retainers etc.

 

Yep PAC-1218. Any hardware tht fits the CC-918 will fit the 1218.

 

I was thinking about this last night, and I honestly don't know what seats/retainers/locks I have since MTI installed them.

So, I have the first broken spring here on my desk at work, I did some quick measurements with a cheap ruler (micrometer is at home and I'm not walking back to get it):
OD- ~1.25
ID- ~0.875 (could be less if you count the inner spring, but I don't think you do)

PAC springs are (according to http://www.pacracing.com/1218info1.jpg):
OD- 1.29
ID- 0.885

Does it sound like the retainers for A should fit the PAC springs, or should I just play it save and get new seats/retainers/locks while I'm at it?

 

Are you current springs a bee hive design. If not, the PAC's will have a substantually smaller retainer.

I would buy the correct locators/retainers/locks for the PAC springs.

 

Measure the OD/ID of the small end (assuming the MTI spring is a Beehive) and I'll tell you.

 

Perfect, answered my question. The MTI springs aren't beehives so they won't work. I was getting slightly confused about how these springs worked.

Got it, I'll have to get new seats/retainers/locks at the same time.