Visit The Dirt Forum for More Information

Author Topic:   lift limit on 1.250 valve springs?
rickb33
Member
posted November 12, 2004 06:51 AM
depends on the spring,what the installed height is and where they coil bind.
There are a lot of 1.250 springs, some will go to .600 lift, some will barely make .480.

However if you are talking about a Z-28 style spring, MOST coil bind around 1.050 to 1.100 and are installed around 1.700 to 1.750 some are less and some are more, but to give you a general answer...you can get around .500 or so lift out of 90% of them, but like I said it depends on the installed height and the coil bind of the spring. You can get by with .050 before coil bind, but I like at least .080.

Oh and BTW they make what is called a .100 long Z-28 spring....and it is just that, and you can get around .560 out of these springs safely.

Competition products has the best 1.250 on spring on the market, it is part #2300, and it WILL go to .600 lift no problem, I use them all the time, in fact it's the only stock diameter racing spring I will use.
Hope this helps!

------------------
Mark's Racing Engines
(903)883-0196
www.northtexasracing.com
engineman@northtexasracing.com

[This message has been edited by engineman (edited November 12, 2004).]

Raz_900
Member
posted November 12, 2004 11:05 PM
Crane 99846 or K-motion 710. They're pricey, but will take .550" easy and .580" if setup right.

I wouldn't use a Z28 spring if it was given to me. I made the mistake of buying what was supposed to be the Pioneer version of the +.100" piece. I'm betting they weren't Pioneer because they all failed. They didn't break, but they collapsed and starting bowing. So they blew all the valve guides out from not pushing on the retainer squarely. And that was with 'only' .500" lift.

istock59
Member
posted November 13, 2004 08:03 AM
I'm with raz, I like the Crane 99846 springs. Tool steel. Seem to last a long time too.


Istock66
unregistered
posted November 13, 2004 06:49 PM           
I used to run the #2300 spring. But never again.

I have broke 7 of them over a couple sets, 4 total sets of heads I believe of mine had them installed. They all had impurities in the spring..

They arent worth the hassle to me, luckily I never dropped a valve into the hole, they were all ss and bent and stayed up.

engineman
Member
posted November 15, 2004 08:43 AM
quote:
Originally posted by Istock66:
I used to run the #2300 spring. But never again.

I have broke 7 of them over a couple sets, 4 total sets of heads I believe of mine had them installed. They all had impurities in the spring..

They arent worth the hassle to me, luckily I never dropped a valve into the hole, they were all ss and bent and stayed up.


Really.....man.....that's no good, could you e-mail me or PM me with a little more info on this problem....heck call me if you can! I cant be having springs break! how long ago was this? I am in no way being ugly,I really am concerned, I did use those springs all the time, I dont use 1.250 springs much anymore, but I still do every now and then,and the 2300's are the ones I have been using.were you using the polished ones or the regular ones?

I have only seen 1 break ever,and I've used a BUNCH of em, but rarely have I ever run them with over about .580 lift.

and you guys are right, the Crane 99846 is one of the best out there too. in fact I may start using them again if 2300's start breaking.

and I agree with you 100% Raz on the cheap Z-28 springs,I tried some of those .100long pioneer springs yur talking about a couple of times with the same results as you, most of them just collapsed...junk,junk,junk!

------------------
Mark's Racing Engines

(903)883-0196

www.northtexasracing.com

engineman@northtexasracing.com


ss99
Member
posted November 15, 2004 11:57 AM
I like the Competition Products springs also. They last and do not lose much rate. We ran them all season with .540 lift at 7000 rpm with no problems. The part number is actually 98213. Other manufacturers sell the 2300 spring. I'd say stick with the 98213 from CP and you'll be OK.



Istock66
unregistered
posted November 15, 2004 04:42 PM           
for me the final straw was a set on double hump heads turned 6500 max. aprox 1200 laps, on pavement, or ten nights...

I put those heads on another motor this year and when I adjusted the valves one was busted.

I replaced it with one of the huge box of used ones I had, and raced that motor packing the track and broke another spring in 4 laps. when the springs were checked they didnt even have 100 lbs on the head anymore??

the couple others I broke were on diff heads, diff sets, from 98-2001. My machinest found one broke when I had detonated a motor in 98, that was my first warning.

the spring I bought was the 40 dollar non polished etc. polishing wouldnt help in my mind because they have all broke from a impurity you can clearly see after it breaks.

I ran a elgin 1091 cam .563 lift max, 1.5 full roller rockers stud girdles etc.

I wanted to run them again as I am now building claimers and back then I was just a tight wad. But Im not going to, I cant afford to break down.

for stock diameter I bought comp 941 springs but, my machinest I have now used a diff spring that he said would last at least 25 nights, and he turns 7-7400 with them. I dont know for sure what it is but he said I didnt need to sweat about them. I bought a on the head rater and checked my 941s when new and periodically in 01/02 because I was so worried about dropping a valve.

fast_crew
Member
posted November 17, 2004 07:33 PM
We used the howards# 98213 Drop in spring for one season. Found a broken dampner on tear down. Also noticed hieghts inconsistant (?speeling) and ends not paralel to each other. This was with .555 max lift and 7000rpms. A friend also tried them, almost same combo with the same results. Our springs where purchased 2 yrs ago friends last year. The friends springs where diff. hieghts and also not paralel when checked brand new. Deffently not worth the $$80.00 from comp prod.

Hope this helps engineman