[C-boStyle™]

I agree with using a 350. A 350 will almost always have more tq than a 327 and will make lower rpm driving more enjoyable on the street. another plus to using a vortec 350 is that it has a factory roller cam.

[Hippie]

Originally Posted by C-boStyle™

I agree with using a 350. A 350 will almost always have more tq than a 327 and will make lower rpm driving more enjoyable on the street. another plus to using a vortec 350 is that it has a factory roller cam.

I gave my 2 Pc. rear main 350 cores away last Fall. I won't use anything but factory roller cam blocks when building a SBC from now. GM made some great factory roller cams for budget street engines. A guy can throw together a pretty good running engine with swap meet parts and crate motor takeout cams and valvetrain parts off eBay. Just like the old days.

[Rickracer]

Originally Posted by automotive breath

I'm thinking more along the lines of porting the Vortec heads, a Comp XS274S
cam. Same flat top pistons with a smaller combustion chamber for a little
more compression. Weiand single plane with a 750 double pumper. Up grade
the connecting rods and swap the 4:11's for a 4.56 and spin it to 7200. Now
we are talking fun to drive.

Not to be disrespectful, but there is some REALLY bad advice here, #1, unless you are a real WIZARD with a die grinder, porting Vortecs can be a REALLY bad idea, it doesn't take much to ruin them, and it takes a LOT of skill and experience to make even a small improvement in them, #2, that is way too high a lift without some serious machine work, stock Vortecs will only accept up to about .460"~.480" lift without machine work or some special springs and retainers. #3, they don't work all that well over 6000 rpm, but the low lift flow is so good they don't need to. #4, unless the flat tops are relatively lightweight and forged, 7200 rpm could mean instant destruction.
I'd recommend a good valve job along with cutting the tops of the valve guides for some PC seals with the proper valve springs to match a mild .480"~.510 lift cam, compression should be 9.7 to 10.5:1 depending on deck height and head gasket thickness, which will run fine on pump gas with the high swirl, fast burn combustion chambers. 375 to 400+ REAL hp is relatively easy with a combo like that, and if that's not real fun, I'm glad I don't live in your neighborhood,

[ap72]

Originally Posted by my87Z

What? AP i do appriciate your knowlege and critisisim but do explain further please. what info was i wrong with?

RHS uses a 4.125" bore to measure their flow. It inflates their flow numbers, most people are unaware of that.

RHS has good heads, but Vortecs aren't that far down in comparison, and the cracking problems are non-existant on engines that are tuned right and not overheated.

$1000 into a good Vortec long block can build you one hell of an engine for a daily driver.

[my87Z]

Originally Posted by ap72

RHS uses a 4.125" bore to measure their flow. It inflates their flow numbers, most people are unaware of that.

RHS has good heads, but Vortecs aren't that far down in comparison, and the cracking problems are non-existant on engines that are tuned right and not overheated.

$1000 into a good Vortec long block can build you one hell of an engine for a daily driver.

i was aware of that AP, and the number i posted (254cfm @.500) came of of the stan wiess website not RHS. RHS has them listed at 268cfm @.500 lift. (but they also used a 4.200 bore, and i still find that hard to believe) but you're right most all head manufacturers do this to inflate there flow number in order to sell heads, i rarely look anywhere but the stan weiss site though and as a rule of thumb i still take 5% off the flow numbers for a more realistic number and even after doing that the RHS 170's are still flowing about 241@ .500 and the stock vortec is around 227 @ .500, the RHS have the same benefits that the stock vortecs do lowing in the lift as well but even better. i do understand that going the stock route is cheaper and will still produce some nice numbers but many like to put larger lift cams and have the stock vortecs cleaned up. even after they have been machined they typically still dont produce what the RHS 170's do and now you have pretty much the same amount of money in them. this is mainly where i stand, i know that some can do there own machine work and that helps them drastically but i and many others still have to pay for ours

[ap72]

Originally Posted by my87Z

i was aware of that AP, and the number i posted (254cfm @.500) came of of the stan wiess website not RHS. RHS has them listed at 268cfm @.500 lift. (but they also used a 4.200 bore, and i still find that hard to believe) but you're right most all head manufacturers do this to inflate there flow number in order to sell heads, i rarely look anywhere but the stan weiss site though and as a rule of thumb i still take 5% off the flow numbers for a more realistic number and even after doing that the RHS 170's are still flowing about 241@ .500 and the stock vortec is around 227 @ .500, the RHS have the same benefits that the stock vortecs do lowing in the lift as well but even better. i do understand that going the stock route is cheaper and will still produce some nice numbers but many like to put larger lift cams and have the stock vortecs cleaned up. even after they have been machined they typically still dont produce what the RHS 170's do and now you have pretty much the same amount of money in them. this is mainly where i stand, i know that some can do there own machine work and that helps them drastically but i and many others still have to pay for ours

That's pretty much the most objective view of it i think a person can have.

If you can do your own porting and run rinned studs though you can save some serious coin by using the Vortec heads that come on a complete long block. I get 4-bolt main 880 Vortec long blocks for about $300-$400. With another $1000 spent on flat top pistons ($100), cam ($250), intake ($200), Springs ($100), and rings, bearings, and gaskets ($150) you have a little change left to get an ignition and rebuild a carb ($200). Hell, even if you have the heads redone you're not in for a total over $1500. If you watched your P's and Q's you could do this build for less than a grand if you surf ebay and craigslist.

A set of RHS 170 heads will eat up more than half of that budget. They're nice heads, but not that much nicer than stockers, especially on a daily driver type car.

I like RHS heads, they sell a good product, but for 400ftlb in a daily driver I think they're overkill. If we were looking at crossing the 500hp mark then they would be a great investment IMO.

[ap72]

BTW sorry for calling you on the RHS heads, most people just follow the advertisements and take them as gospel truth, I should have assumed you knew better.

[my87Z]

Originally Posted by ap72

BTW sorry for calling you on the RHS heads, most people just follow the advertisements and take them as gospel truth, I should have assumed you knew better.

it's cool man, and you're completely right. if you can do the machine work your self than man you got it made. if you dont then you're gonna spend some more coin. like me i bought a set of DART 200cc platinum heads had then angle milled .040 to give them about 58.5cc CB's had all the casting cleaned and some port and polishing and it ran me about 690.00 on top of 1100.00 for the heads but they also flow tested them for me for free and i got inbetween 9-14cfm increase at all lift levels (4.125) with flow of 292cfm @ .550 lift, in which i'm using a cam with .560 adjusted lift from the 1.6 rockers, so for me it was well worth it but i'm using a 4.040 bore so i imagine the real number for me is closer to 280cfm. that's still better than the AFR heads and i get to keep the iron

[automotive breath]

I don’t want to be disrespectful either, we just disagree; that’s OK

Originally Posted by Rickracer

#1, unless you are a real WIZARD with a die grinder, porting Vortecs can be a REALLY bad idea, it doesn't take much to ruin them, and it takes a LOT of skill and experience to make even a small improvement in them.

I disagree, these heads flow ~ 220 on the intake side stock, just a small amount of
work and a good valve job will put them in the 240 – 250 SCFM range. Even
more improvements can be found on the exhaust side. I’ll post information on
how to do this if you are interested.

Originally Posted by Rickracer

#2, that is way too high a lift without some serious machine work, stock Vortecs will only accept up to about .460"~.480" lift without machine work or some special springs and retainers.

Correct, but easily resolved. We run these heads with up to 0.600” lift with
the machine work, LT1 retainers and the correct springs.

Originally Posted by Rickracer

#3, they don't work all that well over 6000 rpm, but the low lift flow is so good they don't need to.

I disagree, they work very well above 6000 RPM if prepared correctly. If he
wants to make good power with a 331 he will need to spin it.

Originally Posted by Rickracer

#4, unless the flat tops are relatively lightweight and forged, 7200 rpm could mean instant destruction.

I agree light weight pistons are recommended for high RPM, I disagree that a
heavy piston like a TRW will instantly destruct at 7200 RPM. I have had my
331 TRW flat tops for over 30 years with zero failures.


PS: I was very conservative with the combination I posted, personally I
would install a larger cam and put 488’s in the rear-end and let the little
331 sing, that’s what I do with mine. Or install a 350 like the others have
recomended.

[ap72]

Originally Posted by rnix999

Goals:
weekend driver, no racing intentions, I'm more interested in driving winding roads but would like some off the line performance.
325-350 hp
350 minimum torque (I do understand that this is a 327 and not a 383)

$ 2500 to $ 3000 budget (hopefully including machine work)

I plan on lowering the compression of the engine to be pump gas friendly (91 max octane in California).

while high revving engines are fun, pay attention to the original goals.

For 3K he could make a 500ftlb 383, but I think that is a little excessive for this application. Instead spend only half the money, exceed the power goals, and spend the rest on a set of headers, a rebuilt carb, and a set of rear tires.

[Rickracer]

Originally Posted by automotive breath

.... Even
more improvements can be found on the exhaust side. I’ll post information on how to do this if you are interested....

My information coms from my machinist, who's done all my work for over 25 years, does a TON of local racer's porting work, even has some national record holders, and owns his own Superflow 600, but I'm always interested in more knowledge and/or different perspectives,

Originally Posted by automotive breath

I disagree, they work very well above 6000 RPM if prepared correctly. If he
wants to make good power with a 331 he will need to spin it.

I used to spin my .060 over 327 over 7500 a lot, when it finally died, it was turning over 8300...

Originally Posted by automotive breath

... I disagree that a
heavy piston like a TRW will instantly destruct at 7200 RPM....

The instant destruction was referring to the possibility of cast pistons. With forged pistons, I think just about any 327 would be quite safe to 6500~7000. I had some fairly heavy Speed Pro forged popups in my 336, and they lasted a LONG time,
BTW, it was in a Vega, had 492 angle plug heads, 4.56s then 4.88s, TH400, 3000 stall, and a .530+ lift solid cam with 1.6 roller rockers, and got street driven a LOT, so I know where you're coming from,

[454C10]

4.11 and 4 spd are the key features here. along with 11:1 cr pistons.

get some 180cc afr eliminator heads. these heads come in 65 and 75 cc. if you have 11:1 with a 64 cc head then 75cc will make 9:6:1 with the same setup.

with aluminum heads you can use 11:1 cr with 91 octane if the cam is big enough.

get a cam with 285 degrees on the intake and 295 on the exhaust with 110 to 112 lsa. You need more duration on the exhaust since you are not wanting to change to headers.

use a 0.040" felpro head gasket. this will lower the stock cr down a few points. 10.7:1cr with 0.040" head gasket and 11:1 with a 0.020" head gasket.

if you don't want to use a cam that big (285/295) then use the 75cc heads (9.6:1 cr) with a cam in the 270 degree range on the intake and 280 on the exhaust. still more on the exhaust since you don't have headers.

if you are going to change the pistons then it is better to use as flat top with a smaller chamber to get the compression you want. (better flame travel).

I would change to flat tops and stroke it with a 350 crank and use 64cc heads with headers and a compcan 292H. use a RPM intake with a holley 750. this engine will make 450hp at 7000 rpms and 400ftlbs. a cheap stock cast crank will work just fine. without headers 390hp, 375ftlbs. Yes, headers make a huge difference when big cams are involved. And make a lot more torque in the mid range even with a mild cam (+40 or 50 ftlbs).

[Hippie]

Now THIS is how we are supposed to argue, CONTRUCTIVE DISAGREEMENT. This is turning into a great thread!

[ap72]

Originally Posted by 454C10

4.11 and 4 spd are the key features here. along with 11:1 cr pistons.

get some 180cc afr eliminator heads. these heads come in 65 and 75 cc. if you have 11:1 with a 64 cc head then 75cc will make 9:6:1 with the same setup.

with aluminum heads you can use 11:1 cr with 91 octane if the cam is big enough.

get a cam with 285 degrees on the intake and 295 on the exhaust with 110 to 112 lsa. You need more duration on the exhaust since you are not wanting to change to headers.

use a 0.040" felpro head gasket. this will lower the stock cr down a few points. 10.7:1cr with 0.040" head gasket and 11:1 with a 0.020" head gasket.

if you don't want to use a cam that big (285/295) then use the 75cc heads (9.6:1 cr) with a cam in the 270 degree range on the intake and 280 on the exhaust. still more on the exhaust since you don't have headers.

if you are going to change the pistons then it is better to use as flat top with a smaller chamber to get the compression you want. (better flame travel).

I would change to flat tops and stroke it with a 350 crank and use 64cc heads with headers and a compcan 292H. use a RPM intake with a holley 750. this engine will make 450hp at 7000 rpms and 400ftlbs. a cheap stock cast crank will work just fine. without headers 390hp, 375ftlbs. Yes, headers make a huge difference when big cams are involved. And make a lot more torque in the mid range even with a mild cam (+40 or 50 ftlbs).

terrible quench, poor heads for the money, and too big of a cam duration split for a NA daily driver. 292H cam is more strip oriented than street. I agree with most of the rest.

TQ appears to be more of a concern than a high winding race engine...

[my87Z]

Originally Posted by ap72

terrible quench, poor heads for the money, and too big of a cam duration split for a NA daily driver. 292H cam is more strip oriented than street. I agree with most of the rest.

TQ appears to be more of a concern than a high winding race engine...

that is exactly what i was thinking

Hippi i'm starting to like you