davep_96

Ok so this summer i finished my 355 build with vortec heads. The car has some pretty decent *****, 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.

blk/slvr02ss

iTrader: (21)

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

Top Secret

Perhaps stepping up to a XE274 would work well?

moge11

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.

ZONES89RS

iTrader: (25)

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.

davep_96

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?

ZONES89RS

iTrader: (25)

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.

davep_96

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?

ZONES89RS

iTrader: (25)

Depends on what it is worth to you, if you want the bad *** 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.

davep_96

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?

moge11

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

davep_96

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?

ZONES89RS

iTrader: (25)

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.

moge11

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.

davep_96

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?

ZONES89RS

iTrader: (25)

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.

davep_96

**** 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?

ZONES89RS

iTrader: (25)

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?

moge11

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

ZONES89RS

iTrader: (25)

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