Small Block & Big Block Chevy Specific - Vortec build...wanting a bigger cam now..

Ok so this summer i finished my 355 build with vortec heads. The car has some pretty decent balls, never got it to the track though. I actually based my build off of a build a chevy magazine did and they had approx. 400 hp. Now however I want to make the car faster. I was thinking nitrous at first, but i dont have forged internals so i heard i could only safely run around a 100-150 shot. So now im thinking of running a bigger cam (i also would rather be all motor). The cam that we used is a comp cams flat tappet, the xtreme energy 262h: 218/224 .462/.469. The reason i went with such a mild cam was because i didnt have the money to buy a higher stall conv. Now i have the money and i would like to get a pretty decently big cam and am looking for suggestions. The car will still be driven on the street but i dont care much about drivability. Just wondering what cam would match up good with vortec heads. Thanks guys.

I would go w/a Comp Cam 244/244/-501/501 w/a 3000 stall and a Holley 650 Double Pumper.

Perhaps stepping up to a XE274 would work well?

Are you willing to convert to hydraulick roller?...assuming your block is pre-1987. If so the XE282 or XE288 would be awesome. If not look into the 231/237 voodoo flattappet. And actually now that Im thinking about the Voodoo roller would be a great choice too. Did you upgrade the springs and have the guides cut before you assembled the motor? If not this will need to be addressed with the new cam. You will Need the Comp 918 beehive springs and retainers. This will take care of all retainer to guide clearance issues up to .550" lift.
You should also you use a 3200-3500 converter regardless of cam decision here.
Also get a 750 double pumper too....That'll help out quite a bit. Use one from Pro-form or Quick Fuel. Best bang for the buck carbs.

The cam i have seen in builds was 230/236 @.050 hyd roller,made 425 HP and 450 TQ, but that is the limit of those heads with a 355 cubed motor, nitrous wont hurt, hit it with a 150 shot and have a blast.

Ok so I guess my question now is can you get too big of a cam for vortec heads? I'm just wondering if there is a point where going with a more aggressive cam won't give me any more power because the heads can't handle any more. I did have the guides cut however I used the stock retainers that's came with the heads.


So say the limit for vortec heads is the 450 hp. If I was to run the 150 shot would that still give me the 150 extra hp or is 450 the max on a 355 no matter how you get there? If I say was making 450 on just motor could I be around 600 up by adding the nitrous?

I'm assuming a bigger carb is necessary with a bigger cam but do I go with the 650 or the 750?

With the heads being a limited factor, ported vortecs can usually make 450 HP with a 383 and a decent cam, but 230/236 is the cam that seems to do so well across the board, i have a 236/242 with .520/.540 lift comp XE roller, it seems to be too much, but i still need to ditch the performer intake and install a set of long tubes to see what really happens, it pulls to 6000 no problem, but in 3rd and 4th it just seems to get sluggish on the big end. I will update when u get the bigger intake. A 650 will do fine but a 750 will give a bit more HP but losing a touch of low end TQ.

So say hypothetically that I am around the 400 hp mark that the magazine was. Is it worth the money and time to do a cam/torque conv swap for just that little extra power, or would it be more wise to hit it with a 150 shot? Obviously id rather have the sound of a bigger cam, and to also be able to say its all motor and no spray, but if im going for a better ET which way is best?

Depends on what it is worth to you, if you want the bad ass sound and a bit more power, then a bigger cam and going roller would be the key for you. I think you might be arounf 380 FWHP, so there is power on the table to be gained with a bigger cam either way, even if you are olmost at 400 FWHP.

So cams seem to be priced around the same regardless of lift and aggressiveness. So could i go with a pretty decently aggressive cam that might be too much for my heads in anticipation of getting better heads down the road, or would that cause me to actually lose power over a smaller cam because the heads cant handle the bigger cam? I do plan on getting racing heads later and id like to just do the one cam swap if possible but if id get more power out of a smaller cam then id do that for now.

Now say i go with the bigger cam, can i still run the 150 shot?

GET THE VOODOO 231/237 flat tappet if u r staying flattappet. if ur going roller get the equivalent.

Yeah I'll probably stay flat tappet. Thanks for the help guys. Another question. I'm seeing on here that some guys are running 11s with bolt on ls1s with a cam swap and stall. Just wondering how the hell that's possible? With no head changes or intake, and no boost or nitrous. I figure a stock ls1 is about 350 hp so with those mods maybe they're at 425 or 450? Say I get around that number like zone said can I be in the 11s? Or are they running huge cams? Didn't think stock ls1 heads were capable of that big of lift and flow numbers... I don't know maybe it has something to do with their suspension upgrades too?

Yeah I'll probably stay flat tappet. Thanks for the help guys. Another question. I'm seeing on here that some guys are running 11s with bolt on ls1s with a cam swap and stall. Just wondering how the hell that's possible? With no head changes or intake, and no boost or nitrous. I figure a stock ls1 is about 350 hp so with those mods maybe they're at 425 or 450? Say I get around that number like zone said can I be in the 11s? Or are they running huge cams? Didn't think stock ls1 heads were capable of that big of lift and flow numbers... I don't know maybe it has something to do with their suspension upgrades too?


The LS1 is a whole different animal, the heads are 18* stock to our SBC 23* heads, they flow very well compared to anything we have "stock". Not to mention with the design of the LSx platform the power curves are allot better across the board.

You can go high 11s with a vortec 350 if your weight is right, they make excellent torque to propel you off the line and the HP picks up were the TQ leaves off and the power band is great instead of dropping off.

LS1 with boltons and full exhaust can reach upwards of 365hp AT THE WHEELS thru a T56. They are 400-420hp on engine dyno. 300-as high as 325++ at the wheels in stock form. The higher horsepower cars are factory SLP modded with a catback and lid in 01-02, along with the factory the LS6 intake. The heads absolutely rock in stock form. Some Cam-only Trex cammed car and the like have dynoed something like 440rwhp.

Ok so if a 365rwhp camaro can reach 11s, why does a 505fwhp vette only do 11.7 stock? Shouldnt that vette be low 11s considering it has more horsepower?

Anyway back on topic...So if im going for a high 11s vortec 355, is that voodoo cam the way to go? And should i opt for the 650cfm for more torque or the 750 for more hp? And approx a 3200 stall correct? What other mods would i need as far as suspension/weight reduction to get to that high 11 mark?

Ok so if a 365rwhp camaro can reach 11s, why does a 505fwhp vette only do 11.7 stock? Shouldnt that vette be low 11s considering it has more horsepower?

Anyway back on topic...So if im going for a high 11s vortec 355, is that voodoo cam the way to go? And should i opt for the 650cfm for more torque or the 750 for more hp? And approx a 3200 stall correct? What other mods would i need as far as suspension/weight reduction to get to that high 11 mark?

LOL, the record for a bone stock C6 Z06 in the 1/4 mile is a 10.98 last i checked.

That voodoo cam he recommended is a great choice of you want to keep a flat tappet engine.

LOL, the record for a bone stock C6 Z06 in the 1/4 mile is a 10.98 last i checked.

That voodoo cam he recommended is a great choice of you want to keep a flat tappet engine.

Shit dude didnt know that! Howd that happen thought they only did 11.7? That just someone whos really good at shifting or something? Or do the magazines just suck at 1/4 mile passes?

Anyways yeah i was thinking of staying flat tappet. What would the advantage be of going roller anyway? Would that be a pricey upgrade?

Yes, the average driver can pull a 11.7 on radials, but a experienced testing/tuner can get the most out of the launch and pull optimal shifts. that is 11.7 with radials for te average driver, now with tires is another story.

The roller advantage is making more power, no break in time for the camshaft, not lobe failure, not worrying about special oils to keep the lobes alive. But, if you have a original 1987+ engine block you can get a cam for about 250ish depending on brad, the roller lifters for a OE roller block are about 100$ for a new set depending on where you get them, or used ones will work fine out of a LT1 or even a LS1 engine, you would need the retainers and extra equipment. For a retro roller kit, you are looking at 550$ for the cam and retro rollers, then a cam button around 20$. So it depends on what you have as a engine block, do you know what year it is?

Just want to make a correction....ZONES, LS heads are 15*!!!!, Not 18*.
LS7 heads use an even shallower angle yet, 12*!

Just want to make a correction....ZONES, LS heads are 15*!!!!, Not 18*.
LS7 heads use an even shallower angle yet, 12*!


Thanks for the correction, i am stuck on small block heads, the aftermarket SBC heads are usually 18*.:bang:

Thanks for the correction, i am stuck on small block heads, the aftermarket SBC heads are usually 18*.:bang:

I know. Just put'n that out there....mostly for others. I knew whatcha meant.

Yeah the block is out of a 1989 chevy pickup. Id go roller for sure if the price doesnt get too crazy compared to a similar cam in flat tappet form. If i stayed flat tappet could i use the lifters/springs i already have? The lifters are Comp part #812-16 and springs Comp # 981-16. I know i would need roller lifters for a roller cam, but could i keep those springs if i went with that Voodoo roller cam that was suggested?

And just to clear something up, the 15* we're talking about, is the angle of the valves?

Well, if you replace a flat tappet cam, you need new lifters anyways. Rollers are re usable, but not flat tappets. You can convert to roller for about 250-300$ or so, with used lifter parts and a cheap roller cam. I found a new roller cam for 150$ that is 230/230 @.050 and olmost .500 lift. Not a bad cam for a budget.




And just to clear something up, the 15* we're talking about, is the angle of the valves?

Yes.

the vortech heads are some torque monsters, especially with a 383. with your setup i agree with what zones is saying. no personal experience but most builds have cams usually 230 or less. i just saw a build with a roller cam i think was only like a 196/206 or so and it made huge tq as well. if funds permit a hydraulic roller cam with 220-230 duration with .500-.520 should work great for you. and then if it still isn't enough hit it with alittle n2o.

Does anyone know where to find the Voodoo 230/237 cam? The closest one i can find on Jegs is 227/233... the next one they have is 233/241...
Thanks, Dave

Give them a call.

Here's another question i just thought of: Do i have to replace the cam bearings? Or can i get away with the ones i have since they have only 2000 miles on them? I'm doing the swap with the engine in the bay and i heard that replacing cam bearings with the crank in is extremely difficult...

Only 2000 miles? Still like new if it was built right, dont worry about it.

Here is a thought since you already have the intake for the vortec head bolt pattern. Get the big port bowtie vortec's for the motor and get that cam that was stated in here earlier. The port volume is 210cc I think that way you can run nitrous and run the bigger cam and not worry about if you are out of the efficiency of your heads.

Yeah i would but cant afford to buy new heads right now. Unfortunately im on a college budget and im stretching it with the new cam, carb, torque conv, gears, etc.

I plan on starting a project that i go all out on and can take my time buying parts as i get the money. Ill still have my TA to have fun with, and ill kinda just build the new engine as i can afford more for it. Then find a car to put it in probably. This car will just be somethin to tide me over till i can build a car with some serious power.

I should just quit modding this one and start saving, but im not really satisfied with the current setup, and i want to squeez a little more out of it before i do. Plus, you all know how it goes with modding. Hard to stop once you start...

Your vortec heads are good to 500hp as cast. Go with a custom ground hydraulic roller with specs of say: 234/240 and run a 32-3600 stall and 750 double pumper.

Your vortec heads are good to 500hp as cast. Go with a custom ground hydraulic roller with specs of say: 234/240 and run a 32-3600 stall and 750 double pumper.

I have never seen this, on pump gas and 383 cubes i have seen them go almost 450 HP.

I have never seen this, on pump gas and 383 cubes i have seen them go almost 450 HP.


I could be wrong, but I could've sworn I read that in a magazine that they are good for 500 horse. No clue what magazine, just remember reading it. Maybe they were talking ported?

Still, the runner volume runs out, it is possible, but not on pump gas and without a mechanical roller.

Does anyone know where to find the Voodoo 230/237 cam? The closest one i can find on Jegs is 227/233... the next one they have is 233/241...
Thanks, Dave

go with the 233/241. The 230/237 is a roller cam. I say the 233/241. Some will tell you its too much, BUT its NOT! You can never have too much cam. Go to Speedtalk.com and ask if more duration is gonna hurt power with vortecs...ask Joe Sherman or anybody else.

Well, my 357 with the comp XE288HR is not cutting it, maybe the intake is hurting it badly, but it seems this cam is just too much for these heads, 236/242 @.050.

What kind of idle is the 233/241 cam going to have? Im wanting a lopey idle...

You would be happy with it.

This is 236/242 duration:

http://i157.photobucket.com/albums/t74/ZONES89RS/th_89flowclip.jpg (http://s157.photobucket.com/albums/t74/ZONES89RS/?action=view&current=89flowclip.flv)

What kind of idle is the 233/241 cam going to have? Im wanting a lopey idle...

It will be PERFECT for U!