Cylinder head?

[MOP]

I have gathered some much info on heads that I am really lost now :confused: . I was going for 2.02 180 runners in a Pro T iron heads.
I am trying to make my power to 5k with good low and mid range power, my machinest is saying go with Pro T or Dart with small valves, 165-170 runners, 72cc chambers which will give me 9.2 compression. He feels that combo will make the power where I want it. Any thoughts greatly appreaciated.

Phil

[rayjay]

I though you were using Chevy's Vortec heads?

rayjay

[MOP]

I though you were using Chevy's Vortec heads?

rayjay

I gave VT's thought and several said run them but my "Best Garu" got me pointed at Pro T's, the only hang up now is the runner size thing. I am hoping some of the other guys in the know chime in.:crossfing, I want to order the darn things and get it over with.

Phil

[Rootsy]

phil,

it isn't rocket science... it;'s just a 383 in a boat... we're making burgers...

hey BUIZILLA... speaketh the gosphel to the man already...

JR - flowed out...

[rayjay]

It's not Rocket Science, but since you have to get heads anyway you might as well get the ones that work the best for your application. From my experience 383's (and 400's) like things one step up from a 350. This goes for heads, cams, and carbs. They seem to like heads that are at least 200cc, with the Vortecs or other high velocity heads being the one difference. Vortecs work very good on a 383 that will not spin very high, as in a boat. Don't be afraid to run a Vortec even though its CFM at high lifts may not seem as good as some other big intake cc heads. Its low and mid lift flow is absolutely incredible.

<http://www.hotrod.com/techarticles/66278/index.html>

rayjay

[MOP]

Thanks guys I needed one more kick in the butt, I am sticking with Jamie and going with the Pro T's 180cc. I can't see buying VT's When I can get the Pros nealy as cheap all setup.

Phil

[turbo2256]

Out of the box the newer Vortec heads out flow just about anything with out going too big on the port volume. Just with a bit of work they flow as much as 250 CFM. Just did a study on it for guy building a vet. I showed him air flow figures on the 180 and 200 Dart heads and Vortec beat both the 188 by close to 200 CFM total and around 70 on the 200's . Differance in CCs 170 for Vortec .... 188 for Dart 180 and 200 for the Dart 200.
The smallest port with the most flow gets you the most HP and TORK at the lowest RPM period.

[turbo2256]

Here are some figures I use for compairison building engines.
A 383 with out of the box Vortec's flow around 235 which can produce 483 HP at 5800 RPM. A mild port on the Vortec's produce aroud 250 CFM which would move the RPM band up to 6172 and possibly 514 HP. This is with a 170 cc port.

[turbo2256]

The Vortec heads I am refering to are the 885's. Also as port volume increases air speed goes down and more RPMs are needed with the same size engine to achive advertized flow figures.

[MOP]

Having been a pain in the butt either calling or mailing so quite a few you super helpful guys, it did help my decision. I may have gone with the VT's the guy had but they were new stripped and he wanted $500 for them, would have spent a bit getting them ready. I am getting the Pro T's real cheap from my machinist, just need to get the runner size settled. Also all the manifolds I have are old style which I will run for now, an "Air" Gap is a must in the future, is a certain someone listening!

I am getting close and do give a lot of thanks to some really helpful guys, I will have my shot a pay backs along the way!

Phil

[turbo2256]

Yeah, I would agree. In our application, stay away from the Vortecs. They dont run worth a crap, just ask anyone who's seen my X run :rolleyes: :wrench: :rolleyes:

MadPoodle if your running 885's there may be other problems. These figures I gave are if you dont stepp on air flow in other ways. INTakes are a problem most dual planes step on air flow the torkers get close and the Victors a bit better. Cam should be around 114 lobe centers, 220 to 230 duration @.05 lift and .5 lift. Exhaust is another concideration it must not step on the air flow either.

[rayjay]

... They dont run worth a crap, just ask anyone who's seen my X run :rolleyes: :wrench: :rolleyes:

Poodle, never saw your X run, but from my experience if your engine isn't running "worth a crap" it probably isn't the fault of the Vortecs. I'm not saying there couldn't be something wrong in the Vortecs, but most likely there is something in your engine / system that doesn't work with the Vortecs. First off, do you have a Vortec intake? If not, there is your problem. I know guys just grind the intake bolt holes to fit, but the intake runners are just too different to work. There is no such (workable) thing as a Vortec / non-Vortec intake manifold! Did someone try to re-work the heads to work with a non-Vortec manifold? In fact, did someone try to re-work the Vortecs at all? Let us know your intake, cam, and exhaust combo, plus what ever else has been done to the motor, and I am sure someone can probably help you.

rayjay

[turbo2256]

I have run the Air Gap and Performer RPM back to back on a 7.4 with nothing more than pocket ported oval port Edelebrocks. I could feel no differance in either except in my wallet. The Torker II I finally used produced real seat of the pants performance it eliminated bow rise and got up to the RPM limiter (5200) with no need to let it air out to pick up speed. Wish I had kept the boat long enough to prop it up.

[MOP]

Right now I have two Performers, a Holley and Qjet. I will run the Holley for now but may play with a Qjet in the future, I have always liked them.

Phil

[Rootsy]

i think poodle was ummm being comical on the vortec comment... ;)

i would have run vortecs when i did my cylinder head change but i wanted to have a wide selection of intake manifolds and perimeter bolt valve covers to choose from... and room for future expansion... plus at that time they were not offering vortecs for anything greater than .480 lift and i didn't feel like going machingning


turbo... been meaning to write you back.. i'll get to it today...

[ToonaFish]

Yeah, I would agree. In our application, stay away from the Vortecs. They dont run worth a crap, just ask anyone who's seen my X run :rolleyes: :wrench: :rolleyes:

Um, Poodle's X18 runs like, like, well, a Deere. Or a raped ape, whatever that is. Or a bat outta the deepest south.

Bunches,

Celene 'victims of facetious Poodles abound'

[MOP]

A Deere. Or a raped ape, whatever that is. Or a bat outta the deepest south.

Toona you have the best :yes: nack for clearing the smoke :biggrin:

[DUCATIF1]

Pace still sells a complete kit for $795 which includes 480 lift set up heads, head bolts, gaskets, rockers, and Edelbrock Performer manifold. Hard to beat. Add Comp Cam and you have easy 375hp 400ft lb tq motor with 350. I don't think one magazine hasn't done build up on that exact motor both 350 and 383 set ups. I dynoed 400 with same set up with well over 400hp and 450 TQ. If I can find sheet I will give you exact numbers. Good Luck

[Riley]

What would the cam specs need to be on that comp cam, in order for a 350 Mag to put out 350+ h.p. with the Vortecs and an Edelbrock Performer intake? That sounds like it would be an awesome, cost effective bolt on package to pump up the 350 Mag/carb motors out there. This is also an engine that an Alpha might survive behind, it the operator uses a little care and common sense.

[Rootsy]

Chris,

what yeara is your 350 mag? makes a difference on roller vs flat tappet.. if it is already roller go that route... you get more with less...

350 pshp is gonna take soething along the lines of the XM270HR... 350 pshp translates into about 380 crank... or scorpion territory... the 6.2 MX uses the Crane 2032 roller and vortec heads... i do not know what the scorpion uses for valvetrain... but they do use vortec cylinder heads...

[DUCATIF1]

I do not have Comp Am Extreme numbers in front of me if you need exact parts I used and are serious email me. For general info it is Comp Cams 268 Xtreme for 350 or 274 Xtreme (needs spring and possible machine work as lift is close to limit from what I remember) for 383 or 400 just call to assure it will clear stroke. For exact bolt in Pace also sells Mcfarland cam which was designed around those heads and put out close numbers. I have said it too many times, unless you have a dyno or are willing to spend money dialing in a engine combo why not just copy build ups in reputable mags to save youself a lot of aggrevation and money. Mkae sure to read parts list carefully to make sure they aren't sneaking in high dollar parts. In higher HP operations it is a whole other ball game. Instead guys by parts not combos. Never buy a part on somebodies word unless they used it in the application you are and can back it up with numbers. Parts are just parts and sorted out combos are what you need. It is easy to get carried away thinking if I spend more it will reward me with more HP. Good luck!!

[Riley]

Hey Jamie! Thanks for the quick reply. The snow is melting up here, and the bay is starting to open up, so obviously my thoughts are turning to boating again.

My 350 Mag is a 1990 model, which I believe is a non-roller. The motor has never been apart, and i think she might be a bit tired. I'm looking at running a SCAT nodular crank, GM p.m. rods, and some form of hypereutectic piston, Vortec heads, Performer Intake, and stock Quadrajet carb. I'm still not sure on the cam specs, that's why I came back to the Donzi board for some info. Out of all the boards I've visited, this site still has the best tech info!

[MOP]

Bit the bullet odered Pro T's 72's 200 runners, using the 045 gasket will give me 9.2. Porgessing at a snails pace but :smash: things together :)

Phil

[Rootsy]

straight plug i hope....

[MOP]

Yup straight plugs for sure Jamie you put me wise to that one back awhile. Waiting find out which springs Lunati wants us to use with the cam. Slowly chipping away!

Phil