oxrabidus

Im doing a vortec head swap on my 85 camaro, and i ordered a summit 1103 cam, the lift specs are .442/.465 in/ex (respectively)...
i checked my retainer to seal clearance and it came in a .520in, now with the .05 margin that leaves me with .47 possible lift, i also measure the spring diameter, and it came in at 1.23in. (I always thought they were 1.25, my question is i know that vortec heads came with weak springs, which would be a cheap/affordable replacement for these heads? i have also heard that open pressures of more than 250lbs can pull out the studs, so i am at a loss of which springs to get, i have looked for springs to match my numbers, but cant find anything good...
thanks for the help

InfernalVortex

iTrader: (4)

I use Comp Cams 981 springs which are matched according to comp for their xe262 cam which is .462/.469 lift and 218/224 @.050. Same general neighborhood. I have screw-in studs though. I'd suggest you consider getting screw in studs and machine down the valve guides so if you ever want to go to a retro-roller setup, you wont have to pull the heads off.

Notice the xe262's .050 duration is 218/224, but the total advertised duration is 262/270. Now different cam manufacturers measure this stuff differently slightyl so take it with a grain of salt. But that summit cam is 214/224 @.050 and 272/282 total duration. Notice how much bigger the total duration is on the summit cam despite it being smaller at .050? The xe262 has higher lifts (barely) too! That means that summit cam is going make less torque down low and have a narrower power band, and probably make less peak power. It'll sound good, probably, but it's not going to be as fast as a more modern grind like the Comp XE series or the Lunati Voodoos.


I know you already bought the cam, and it will work, but if you can swing it I'd suggest you consider going with something better.

oxrabidus

i understand that, i bought the summit cam because it was affordable, and i heard nothing but good things (it is basically a copy of the performer cam), the ramp rates are smoother than the MUCH more aggressive XE or voodoo grinds (ID love an XFI grind on a 110lsa for a carb!), but this is only for temporary purposes, money is tight right now (very tight) and i need a running car, and to out up a beter fight at the track...
plus im positive the 1103 cam will make much better power than the stock l69 cam... and the power band should be pretty wide considering it has a 112lsa, opposed to the XE's 110 (if im not mistaken) and the XE is advance 4 degrees (106intake center), the 1103 is just advanced 3 degrees (107intake center)
once everything is settled economically, ill build me another engine.

I can reuse the stock retainers with those springs right?
and the damper clears the valve guide??

skinny z

As far as springs go, I use Comp Bee Hive springs.
A little pricey however they drop in with no modification or machining. They increase maximum total lift to around .550" as well.
http://www.carcraft.com/techarticles...ade/index.html

oxrabidus

i have been thinking about those, what about ls6 springs? they are the same od/id i believe, and the same at the top too? i would just need the locks to match the thicker valve stems.
but ls6 springs cost around 60 bucks

vetteoz

iTrader: (13)

ZZ4 /LT4 springs

http://paceperformance.com/index.asp...D&ProdID=24732

skinny z

Found this after a quick search.
https://www.thirdgen.org/forums/tech...tec-heads.html