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cam questions with vortech heads

8K views 6 replies 4 participants last post by  eric32 
#1 ·
hi im mike iim new to the site i have a few questions im building an sten with a 350 so far i have together a 350 from a 1989 camaro 4 bolt main edelbrock performer intake holly 750 and a mild cam i want to run a big cam to get the sound and power like comp cams new thumper cams i want the big mutha thumper or possible the mutha thumper but i dont know what to do about the stock vortech heads what mods will i have to do to run a big cam and i have a 3:73 posi and a 700 r4 i want a sunday cruiser and i want to be able to take her down the track
 
#2 ·
Don't worry there are alot of guy's here with the info you need.
When they start seeing this you will have several replies. I am not real familiar with the vortec stuff but we are never to old to learn and i am still learning :mwink: . But someone will be here soon. :thumbup: But i am sure you will have to do some work on the heads to run a big cam like you want.
Especially if you want to run the track from time to time.
I know you are going to want it to perform at it's best and not just have a mean sound right.
Cole
 
#3 ·
Well if your wanting to run a comp big mutha thumpr cam you will need at the very least a 3000 stall convertor with the turbo 700r4 and you will not have a every day type cruiser like your wanting and the 3.73 will work ok in town driving but once you go down the highway with the overdrive your engine will not run worth a crap as it will lug somewhat and not be in a decent rpm range for that cam to run well.

Why do I know this well I had the roller version of this cam but with a 350 turbo and 3.73 gears and it worked good with that but I don't have overdrive and with the big drop in rpms on the highway your cam will be nowhere close to where it will want to make it's power band range.

That cam will be a disaster to tune with any type of carb and your timing will have to be so dead on that if just by a bit off you will have issues. That cam will give you performance but it is a blend of both made for sound and basic performance and nothing more. If your not going to race it then go for it but you will maybe just want to go with the thumpr cam. Its got a nice little lope to it and will be the easiest of the three for street use. The two bigger ones you will not like for wanting to cruise on the street.

I got rid of mine cause I got sick of the 35 degrees @50 of overlap and the headaches of trying to get my carb tuned right. I swapped it out for a much smaller lunati voodoo hydraulic roller cam and I shaved off half the overlap and gained some much needed vacuum for breaks and now my carb tunes like a breeze and I gained some better horsepower and torque as well since the voodoo cams will give you more power and a better overall response compared to the comp thumpr cams.

Go with something from the lunati voodoo series or the comp xtreme energy series cams or look into the older magum cams. They are much better for what you want. You will only have about 6 inches of vacuum at idle with the big mutha thumpr cam.

On the vortech heads they are only good for around 460 lift the most with 1.5 ratio rockers being on the safe side. I read but hopefully someone can help out here if you get a set of z28 springs from gm and if you remove the inner damper you can install them on the vortech heads and can take more lift but how much I don't know. The other way is you have to get them machined to go wtih bigger springs.
Eric
 
#4 ·
thanks bud thats what i have now is a lunati mild cam and it runs like a machine i love it so much tork and thottle response and sorry im just starting to be a gear head i just graduated and been working and just wanted to do like to get a little bit more of an edge on my truck i was maybe thinking mutha thumper cam i just want the sound of a big cam i got to have it i looked up the specs on it im pretty much in the range i got a 2500 stall and headers performer intake holley 750 and i wanted to build them vortech heads up a lil to take a more aggresive cam,lifters,double timeing chain,vac canister,beehive springs,proform roller rockers, and some stronger pushrods
 
#7 ·
Well if you want to run the mutha thumpr cam then your stall is pretty good for that cam but don't use the bigger big mutha thumpr cam it is too much for any driving and you will loose bottom end big time with it. As far as heads I guess I missed that an 89 motor would not have vortech heads.

Regardless of what heads you do have if they are factory production gm heads then work will have to be done at the machine shop to machine the heads to go with bigger springs.

I do believe you can get some 1.250 springs wich will fit stock heads without any machining but you must get the right valve seals along with the right matching retainers and keepers. Check out jegs or summit and get a catalog and look through it for springs.

Your stock stuff will not work with them. Trust me I have been everything from stock heads to two different aftermarket heads and stuff has to match.

Good luck on your build
Eric
 
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