Will stock valve springs be ok with 206* .425 cam??

[Donniejr81]

I'm in the process of doing a stock/slightly modded rebuild on my 84HA engine. The cam I am using is 206*/206* and .425/.425 flat tappet, and I was wondering if stock valve springs will suffice, or will I have any coil bind or valve float probs with this cam and stock springs? The car will be street driven and may not ever see a strip. I wass wanting to get some input before I started the valve job and reassembly of the heads. Thanks in advance.

 

[bison]

The stock springs are barely adequate for the stock cam when they are new. Putting a larger cam in and not changing springs is a waste of time and $.

 

[Donniejr81]

Thats kinda what I figured. I have a set of new stock replacements, but after hearing that they'll stay on the shelf a little longer. What valve springs would you recommend using with that cam? Need a decent one that wont break the bank.

 

[Eticket]

LT1 Valve springs are a good cheap alternative. i believe they are just a slightly stronger spring from stock (if not directly a stock replacement).

 

[Donniejr81]

I'm assuming its the 90's era LT1, because I know Chevy made an LT1 in 70-72. What about keepers? Stockers OK, or do I have to use different ones with the LT1 springs? Thanks for the input guys, keep it coming...I need all the help I can get, being a recent Chevy convert:biggrin:

 

[Eticket]

LT1 springs are from newer LT1's yes.. and stock retainers and valve locks work just fine. Many guys have been 10.6's with the 206 cam and ported heads.. is it a comp cam? or something else? I'd highly recommend the comp 206/206.. though it was more than 4.25 lift though.

 

[Donniejr81]

I'm pretty sure the cam I was looking into is a Lunati. You say the comp cams unit is pretty good?? Any idea how much higher the lift is? This is going to be a strictly street car...probably never see a track. Would that one work OK on the street as far as idle and lowspeed driveability goes? If it'll work fine, then it gets my thumbs up as I havent heard anything good or bad about the Lunati cam.

 

[Eticket]

The "old" news on Lunati's were that they were prone to going flat. So were the Reed cams. since, I haven't used any directly, I can verify that at all.

I'm 99.9% sure the comp is part number 69-234-4. It's a .425 lift. So, it might actually be the same as the lunati. You can find it on comps and full throttle's websites.

Let's hope someone else chimes in with some experience on the Lunati. I've only used the Comp on 2 friend's cars that were 11 sec rides. I knew 3 other guys that went 10.60's on this cam with Champion ported irons.

I drove a car with a 12" stall converter and big 63 turbo, and it still spooled like mad with this cam. I can't see any downfall in using this cam at all.

 

[SRGN]

The Comp 980 springs will work well with that cam, only $46 from Summit Racing COMP Cams 980-12 - COMP Cams Valve Springs - summitracing.com

 

[Donniejr81]

Thats all the convincing I need, Comp Cams it is. I hadnt heard anything about Lunati, but Ive heard plenty good about Comp Cams. So, a Comp 206*/.425 cam and Comp 980 springs will be my poison. Will my stock heads and ports be a hindrance with that cam? Should I gasket match the intake and heads and smooth the runners a little, or will I be OK on flow? Thanks again.

 

[Donniejr81]

Another question I have is how would I go about setting the lifter preload with a bigger cam? Ive heard that anytime you go up in cam size on a Buick, you have to get custom length pushrods?

 

[mikestertwo]

Another question I have is how would I go about setting the lifter preload with a bigger cam? Ive heard that anytime you go up in cam size on a Buick, you have to get custom length pushrods?

If the new cam has a smaller base circle then you will need different pushrods. Get an adjustable pushrod and set it so you have .035" preload on the lifter and measure it or adjust it till you have zero lash, measure it, and add .035". Either way will work. Then order a set at that length.

 

[Donniejr81]

Thanks I was wondering how Id do that.