Okay I will be building my 355 and it currently has 76cc heads on them. My question is what heads can I run for best hp output? And can I run 305 heads without any problems and if so what would be the benefits?

 

What is your horsepower goal?

 

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Okay so where should I go with head choice then?

 

Noone knows how much power you want to make.

 

Or more importantly how many $$$ you have to throw at it ?

 

Decent amount of power, I'm just looking for an idea of heads to keep my eye out for right now.

 

Save your pennies and do it right with aftermarket heads if you want 'decent' power. Otherwise, settle with what you have now. Vortecs are an option, but you're severely limited in many regards and you'll pump some money into them getting where you want to be at... And by that point you probably could've afforded a decent set of used aftermarket heads.

Power is not cheap, and cylinder heads are your primary source for making it.

 

I know this, but what I don't know is what heads work best on a 355?

 

There is no best. What's best for one person may not be best for someone else. You need to have a goal. There are lots of of good head manufacturers and some are expensive. Look for AFR, Brodix etc if you have money, look for RHS, World Products etc for something cheaper. What do you want to do with your car? Drive to work, race? Narrow down what you want it to do and how much you are willing to put into it.

 

For EVERY car, there is only "what is most suitable for driver _____ ". Example: I have solid motor mounts going into my car. That's what's BEST for me because I desire the gains that can be had from them. Some people freak out if they get the slightest squeaking or vibration in their car. Our goals might be the same ultimately, but how we choose to execute them are completely different.

It's all math. That's like saying the best numbers are 2+2 because it makes 4. Well, we can also get 4 by dividing 8/2, or 2x2. They all gain the same result, just differently. There is not 'best parts' in the car world because everything can be used effectively given the right situation.

 

Is this for a carburated or TBI engine?
Is your goal 400 hp or less?
If so, find a set of used Vortec heads for $300 or less, spend $120 on a spring/retainer kit and valve seals, and run any cam up to .550" lift.
Vortecs are capable of much more than 400 hp, but when you get into the cams and required spring pressures to support that, you have to put more work into them such as screw-in studs.
If it's a TPI setup, then the Vortec-specific manifold options get more expensive, so if that's the case, you may want to look for some conventional aftermarket SBC heads.

 

the cost of stock vortecs vs. the price of aftermarket ones that places like summit sell is quite a difference, and coming with screw in studs and set up for bigger springs, its stupid to redo a set of vortec heads unless u just have them laying around, theres a company called EQ that makes an aftermarket vortec with 2.02 valves, screw in studs, and thicker casting than a factory vortec, and my machinest swears by them. ive seen them first hand handle the abuse my buddy has thrown at them in his 383 with 255 or greater duration and 570ish lift.i dont know exactly where u could get them, but my buddy got his off his blueprint engines 383, and i almost got them for my build, but it was still cheaper to do up the tpi heads. my machinest uses them often for a stockish replacement for rebuilding peoples engines, a stockish type head with kickass flow numbers, and horsepower capabilities.

 

and also the springs that come on those can handle .575 lift, i know this because i got them from my buddy out of those heads when he upgraded to a larger cam, hardened retainers also, and stronger locks too, i set those up on my tpi 081 heads and also u have a set of 305 heads u want to use? unless u have dished pistons id toss that option i only stayed with my tpi heads since the block i had came with dished pistons setting me at 9.2-1 with the tpi heads with 58cc chambers, flatops would throw u to nearly 11-1 which is unstreetable in my opinion on iron heads, unless u wanna run straight race gas lol.

 

I went with a set of World Sportsman II heads for my 355 build. 64cc chambers, 2.02 intake, 1,94 exhaust. Nary an issue with them! Motor runs great. I went for a daily driver street build so it's much milder than I had originally planned. Still, I'm running 300hp at the crank (est.), 238hp at the rear wheels on a chassis dyno. I love how the car pulls and runs.

 

error on my first post i meant to say cost of redoing stock vortecs or buying aftermarkets that are already set up, is a huge difference in cost when u add up cost of redoing the vortecs, i myself wouldnt redo them when the aftermarket is so available, and chances are those heads are tired if u do find a set of vortecs, never know what your getting into with used heads, guides, valve jobs, possiblities for cracks, needing to be milled etc.

 

what cam and carb u runnin ozz?

 

I'm running the factory CC Qjet, re-tuned for the 355 because of the cam.

The cam itself is a Lunati Voodoo 60121 but they've re-numbered it.

Lunati Voodoo 20080721

Other info:

700R4, 3.73 gears.

The link in my sig goes to my cardomain page if you want to know more.

 

Advertised Duration (Int/Exh): 270/278
Duration @ .050 (Int/Exh): 221/229
Gross Valve Lift (Int/Exh): .515/.530
LSA/ICL: 112/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1800-5800
Includes: Cam Only

im really surpised your only making 300 horse at the flywheel

 

I didn't have the carb dialed in when I did that dyno back in 2010. I am moving this summer back to the States and I will probably have it re-dyno'd, either before I move from the UK or once I get back. I'm pretty sure a good tune will do wonders for the numbers.

 

I'm also still running the factory torque converter. I need to change that, maybe when taxes come in. We'll see. It runs ok, but I'd be much quicker off the line with a 2200 stall (factory is about 1700).

 

i bet its a carb and timing issue making that low of numbers on a set of heads that nice, u should make nearly 400 horse at the flywheel with that setup, im making around 370 horse and over 400 torque with my 081 305 heads, port and polished to the max of course, and competition valve job, and my cam specs are 234 intake 244 exhaust duration, .487 lift intake .508 exhaust, but also i have 10.2-1 compression ratio

 

yeh im gonna try and run stock torque converter, on my cam it recommends a 2200stall i think, im gonna try it with out, if its a dog then if so im gonna put in a stall.

 

Like i mentioned earlier, I went with a milder build because it was going to be my daily driver, so I'm only running 9.0-9.3 compression or so (Estimated). SRP pistons. I also forgot to have the block decked so the pistons are in the hole an indeterminate amount. I wanted to be able to run on regular octane.

 

yeh i run just fine on 93, i dont mind it i usually run 93 in my 5.0 mustang anyways, and thats my daily driver. and i believe undecked is like .035ish

 

pretty sweet setup on the car tho, nice bottom end.

 

Thanks! I always figured it should be good for 350 or so HP, but like we both agreed, it's all in the tune! I met a guy here in England and all he does is Pontiacs. Who knew! England! He re-tuned the carb and did some other small stuff for me. I'm going to see if he knows someone who can dyno it as well.

 

yeh my carb was tuned to the cam i put in, basically i just buy all my buddies old stuff, i have a 1411 edelbrock 750, and it runs sweet

 

ur rotating assembly is rated for 500 horse, and thats pure strip/circle track rating also. not even gonna touch it with regular daily driving

 

Well..ORIGINALLY, this was going to be a 400 small block build. I was going to copy a build that was 505hp, 540 ft-lb of torque.

Then I got orders sending me overseas. I tried but couldn't sell my car. Sold my wife's car, stored our Taho, and brought the T/A with me to England. So I had to make it a daily driver and my my dreams motor 400 small block wound up being a 355 from a 98 silverado.

 

atleast its a roller motor, wish my block was, only plus of my block is its seasoned and proven, but .60 over, this motors on its final bore. lol

 

Mine is .030 but only because I had to clean up one of the cylinders. The guy in the siverado "blew" the motor. Spun the bearings and ran it out of oil while mudding. Got water or something down in it. Engine builder said he got it all though when he built it for me. 30K miles later, still running strong!

 

my motor had effin perfect cylinders except for one, engine sat with coolant in it for 7 years in a garage, so got through the head gasket and into one of the bdc cylinders, causing slight pitting u can only notice in direct sunlight, most of it came out with a bottle hone

 

Maybe I missed some info in a post but you want to run a 234/244 cam with a stock converter wont happen.

 

yeh im gonna run it without for now, until i invest into one, my buddy ran a 2400 stall with that cam

 

amazingly the cam has a 112 lobe sep. weird for a cam that big, thats about the only thing making it nice and streetable

 

That LSA doesn't make that old generically copied copy of a generic copy of a generic cam either "nice" or "streetable".

After as many posts on as many Internet forums covering as many brands, body styles, and age ranges of cars as there have been by people disappointed in the performance of that old cam, it just amazes me that anybody would still buy it. There's even posts from people saying "everybody told me so and I refused to listen but now I see they were right", and it still doesn't do any good. It's tied with 151 repicas (the "350 HP 327" POS) in that department.

The problem isn't about "making power"; it's about how, any modern cam that makes THE SAME power will do so on about 70% or less of the fuel, will idle better, will have better bottom-end torque, and will work better with less converter & gear; or conversely, any modern cam with THE SAME level of all those other "big cam" shortcomings, will make ALOT MORE power.

Mostly it has to do with the fact that as a species, humans have learned alot about how to make better cams in the 40 yrs since that old generic series incuding that abominable thing was "designed"; and, all of the stuff surrounding the cam - transmissions, gears, speed limits, driver expectations, fuel properties, costs and availability of other parts like valve springs, CNC casting of heads, and so on - have completely changed while it has NOT, rendering it obsolete.

If you've got that cam, sell it to the next "greater fool" (yes, there ALWAYS is one of those, it seems; just don't BE one of them) and get something better.

 

I'm still amazed that people buy pre-ground shelf/generic cams when custom cams can be had for the SAME price. I feel like I preach it on this forum religiously now, heh.

 

paid 50 bucks for the cam from my buddy, reason being i was trying to see how much power i can make for under a grand, whether or not im dissapointed and most likely will without running a stall, thats something i wanna see first hand, a tranny swap isnt a big deal, and worth seeing exactly how a car reacts in person without a stall i wanna see, and i dunno how generic of a cam is, but it did come out of a "blueprint 383" 405 horse 440 tq motor, and ran sweet in my buddies 383 when he was running it, videos of him doing burnouts in a abandoned movie theatre parking lot somewhere on youtube, also the rpm range of the cam is what attracted me, i was able to retain a stock bottom end, reason being this cam makes peak power in the 5500 rpm range, alot of cams i were looking at were like 6400 rpm cams and still not even matching that duration, and that is not nice on a stock bottom end, atleast how i wanna drive it, and my tune port heads wouldnt have flowed that much rpms either, woulda had to run my bowtie heads, with a much bigger cam, and had way less streetable of a motor in return, atleast less low end, which im looking for, because this isnt one of those race builds, just something with a good amount of power that i can drive around my small town with a rebel flag on the back of it, and some rediculous exhaust. even tho this cam may be a little bit "big" for my heads, its still gonna give me good down low power and excelent midrange even if i have to run a 2000-2200 stall.

 

Hi Ozz: what pistons were you running? Flattop or dish? How many cc's if they were dished? Did you calculate the compression ratio? Thanks

 

Oh youll see alright. It will die every time you stick it in D.

were trying to help you from doing things over twice bud....cause most of us have lol.

 

haha yeah, i mean its got a low powerband, so im gonna try it, for now, when i get back from bootcamp, quick torque converter swap forsure

 

CAM:.487Int / .508 Exh & 234 Int / 244 Exh duration @ .050 - 112 degree lobe sep.HORSEPOWER:405 @ 5500TORQUE:440 @ 4200COMP RATIO:9.5 to 1 (requires 91 octane fuel)IGNITION TIMING:34 Degrees Total (at 4000 RPM)WARRANTY:
30 month / 50,000 mile
NOTES:This engine requires a 400ci weighted harmonic balancer, and late 350ci weighted flexplate/flywheel.

Blueprint Engines recommends a 2000- 2400 rpm stall converter.

this is what the info on my cam is, factory stall is like 1500-1800 right?

 

They are dished, either SRP or Speed Pro hypereutectic pistons, I'd have to dig out my paperwork to be sure, but they were rated as 9.3:1 compression pistons. What that makes my overall compression with my combination I don't know.