I bought a 383 from a friend to install in my camaro last winter. I got it installed and it runs well but horsepower is addicting and I want more. The motor came with World s/r torquer heads that were supposedly ported and polished. The s/r's are currently equipped with 1.5 roller rockers. The only cam specs I know is that it's a custom grind Ultradyne 288/296 (I know nothing about cams). I also have a Edelbrock performer rpm intake and Holley 750cfm vacuum secondaries on the motor. My question is: Would I benefit from just upgrading the heads to AFR's and leaving everything else the same on the motor? If so, What AFR heads should I be looking at and how much gain could there be? If you need more info just let me know.

Thanks in advance for any advice.

 

so...nobody has any input?

 

It's a tough call without a boat load of specs.
Things like static compression ratio and full cam info are imperitive if someone were even to take an educated guess as to what you might do to find more power.
First thing is to find out whatever details you can about the engine. Piston type, specs on the heads (other than s/r torquers), real cam timing and how it's installed.
One thing you should do is a compression test. If you find that cranking pressure is down across the board, (say 160 or less {which is not to say 160 is bad}) that will indicate one thing. It'll be easy for someone to jump in and say change this and change that however what you have may be just what you need with maybe a modification or two.
Consider your objectives too. Do you want a 8000 rpm missle or a fun daily driver or something in between?

 

I think those heads are way to small for that 383. Is that a hydraulic roller cam or a solid roller or something else?

Duration is good and Ultradyne has made some good cams. The duration looks like some popular solid roller grinds that want to rev up a bit. A good set of 195-210cc heads will open up that combo but we need to know abit more on the cam and abit more on the heads. I dont think they can be ported out that much to feed a healthy 383 since they are small to begin with.

Also what compression?

 

here is the info I got when I bought the motor. The guy said he has the cam card somewhere but could not find it. I'm not opposed to swapping a cam.
Thanks for the advice.

 

so it's a hydraulic roller cam and 9:1 flat top pistons. I want the car to be a sleeper Berlinetta. The power that this motor puts out now is plenty to get me in trouble. However, I would like to be able to be a bit faster than the new Camaros and Mustangs. I only drive the car about once a week in nice weather.

 

Just a few things I see.
9:1 pistons is a bit of a misnomer. That doesn't necessarily relate to the actual engine compression ratio.
The cam card is vitally important.
As Orr suggested the World S/R heads (as in Stock Replacement) aren't particulalry large. Somewhere I have flow specs on them however I'd say it's safe to say they'll limit your upper rpm potential.
Which brings up another point. The stock length 400 rods limit rpm potential as well.
Quoting David Vizard on the subject " ...(power robbing) increased piston to wall friction...wear out bores at a phenomenal rate if the engine is turned to any significant rpm".
From the sounds of it, you may want to enjoy what you have.
If you're serious about improvements then: a) you may want to pull the heads and determine what the actual compression ratio is. Checking the pistons and determining piston deck height is the only way to find out for sure. b) Get your hands on the cam card or find the actual cam specs somewhere.
From there you may be able to make improvements in the cam/compression ratio relationship keeping in mind the limiting factor of your shortblock with the cast crank and 400 rods.
Topping the engine with a premium set of AFR heads, to me anyway, would be a waste of time and money until the details have been worked out. Regardless whether you swap the cam or not.

 

IF its a true flat top piston, most likely its between 5 to 7 cc reliefs which will give over 10.5-11 to 1 with normal piston to head clearance and 64cc heads

I dont know what the s/r's are, but they are iron and that much compression with iron usually doesnt work out well on pump gas. Cam seems to have some duration so it may be able to work on pump gas but its got to be borderline.

But as said above, we need more details on the exact combination to determine if heads will help you. A higher compression 383 with 288 advertised duration will want to rev up abit unless its a very lazy lobe. I am assuming around 230 deg duration at .050 meaning you will want to be around 6000-6200 rpm in which a set of AFR 195's will be great. But depends on what the real compression is and if you want to chance reving stock 400 crank/rods that high. If its a lazy cam it may be 215-220 deg on intake and 5500 rpm peak out of the car which is fine for stock style bottom ends.

 

Thanks for your input. Its nice to be able to come on here, ask a question, and get a knowledgeable answer. Like you guys said, it would be easy for someone to come on here and just tell me to go out and buy a $2000 set of heads.

From your answers I think I will just leave well enough alone with the motor. The car runs great and puts a smile on my face all the time. I took it to the strip once and ran 14 seconds flat and that was my first time down the 1/4. I think with some better tires I could be a bit faster (maybe low to mid 13s). I just have that mentality that if a little is good then more is better (read horsepower). But it sounds like unless I spend a huge amount of money on a new forged crank, pistons, rods, cam, and heads, I will be stuck with what I have. Oh well, I only paid $1000 for the motor. It's much better than the LG4 that was in the car.

 

I agree without knowing all the specs its hard to say. But 14 flat outa a 383 just dont seem right to me... i was at a 14.6 with my L03 on street tires... I mean dont get me wrong 1000.00 for a 383 is a good deal.. but my 2 cents...those heads are choking it out your engine is breathing through a straw and it needs a firehose.... if you do decide to do a set of head look into the 195-210 cc intake range, will really bring that 383 to life

 

Sale here on Pro-Filer heads for 950 complete. 195cc is what i'd start with

 

Where is the sale? Do the Pro-Filer heads have good flow out of the box? I don't want to have to do a bunch of work to a new set of heads. What about Trick Flow heads?

I won't be doing any of this till about the middle of winter. I'm too busy right now with other work.

Thanks again!

 

I have a question. Why limit your choices to AFR? Have you seen the profiler special I'm running. Give up nothing and save $300 . A Profiler 210 with 2.08 valves would work beautifully. Best. Bang for the buck in the market and 100% American made.

 

I don't care what the name on the head is as long as it makes more power than what I currently have.

 

Then give Profiler a look. WWW.profilerperformance.com. I have a special for a no profit $950 a set. You'll give up nothing and save some money for other upgrades. Im at my sons soccer game. My cell number is listed give me a call

 

according to the flow numbers on these heads they are worth money.. id go with the 210's for the 383.... but then again i went with 200cc for a 355 but they do great!!!