dizwiz24

Im hoping to get the attention of AFR, Trickflow, Dart, etc. Im angry.

I want to know why there is stuff like this available for LSx motors, but not ours.

http://www.lingenfelter.com/mm5/merc...egory_Code=C40

This head flows 395 cfm @ .650 lift.

AFR's best, competition ported LT4 eliminator 227cc head flows 324 cfm @ .650

There is no way that we too cant have technology like this. Yes I realize LSx heads are magic with 'cathedral' intake ports and narrow angle valves.

However, we should be able to get those too. If I could start an aftermarket head business I would offer those same cathedral port and narrow angle valve features by also manufacturing a special intake manifold to be used with those heads. This way it would fit LTx and SBC motors. If you have to buy a high rise hood to fit it all, so be it.

The key to making this work is to also sell a special, new-from-the-ground-up, intake manifold to fit them onto LTx based motors.

The market for this heads-intake package would be huge. With all the bazillion SBC project cars already built out there.

I wouldnt rule out some conspiracy between AFR, trickflow, and GM to try to 'force us' to 'step up' out of our SBC and LTx based motors and buy new LSx cars, engines to support their business

tblt44

cv67

Conspiracy, you serious?

Were lucky to have aftermarket support all the money is in the LSx stuff. Try valve angle for one, youll only get so much out of a 23 degree head for starters and these companies are constantly raising the bar.

Beach Bum

Actually, what you want I think it exists.... I think it was World Products, but not sure that developed a gen1 block that could be used with the LSx generation cylinder heads/intakes. I read about it somewhere.... think there is an article floating around somewhere about it.

I think it was mighty expensive though....

Of course you also have the 18 degree stuff that will easily perform with the LSx stuff..... not always cheap, but is getting a bit more manageable on the used market.

Beach Bum

Here is the article.... I don't know if it worked out though, I haven't heard anymore about it.


http://www.hotrod.com/techarticles/e...ine/index.html

ZD1

the head flow went toward the the SB2.2. If you are serious, you want CFM...and have the cash to go 12 or 14 degree heads Brodix for one is a good head. But at that flow you'll need intake (not that hard) and exhaust (custom headers).

You didn't say what you wanted to do with your 385 CFM? be bad? Go get some open exhuast. Low end torque...stroke it and gear it.

In reality, the Gen I has not CFM issues/limitation, but rather has heat flow and stiffness issues. The later generation is going to do that.

The LS heads also have a tall narrow port which allows ram air even with the big port. The "legacy" SBC heads are port limited to the valve train and port hieght.

The true secret of power is maximize the CFM and the power factor. The power factor is most likely between 1.0 and 2.0, unless you do something funky. TPI motors (restrictive) make 230-250 HP on 218ish of flow. LT1 makes 300-325 on 218ish of flow. The right cam/intake can raise the ratio higher. Give up some low end torque...you can push 1.8. Your race motors (tweaked for upper rpm only) will be 2.0 or higher.

in short, 385cfm is available in the race only heads. Look for $2-3K for them and another $2-3K in porting (if you can find someone that can hit the mark).

Or just stop complaining and buy a GM LSX block

dizwiz24

Right here, the point you are trying to make is the point im trying to make.

Q: Why is everyone limited to a 23 degree valve angle?
A: So an LT1/4 intake manifold fits on it.

Q: Why do we need an LT1/4 intake manfold to fit on it...
A: Because everyone is apparently too lazy to make a special intake that could support a 'taller' LTx head with narrower valve angles - like the LSx head.

If you have to put a high-rise hood on it to fit it underneath than so be it !

tpi 421 vette

There is no rumor, the AFR 245 does flow 350cfm, but that's at .800 lift peak. It flows 330@.600 336@.650 and 341@700 and 350@.800. It won't be available until probably the first of the year. And it is a first gen/L98 head, not a LTX head. I have heard of guys converting L98 heads to work with LTX motors, but that would obviously take some work. And most of the heads that have huge flow numbers including LSX heads also have a big port volume. So they aren't for everybody. You need alot of cubes and rpm or a little less cubes and even more rpm.

C409

You'd have to re-invent the small block ... Dang ! That's been done already by GM ............................... they call it LSx ..............

USAsOnlyWay

People run short angle heads all the time. You are right, totally doable. It isn't laziness though as you say, it is a market where 3k-6k cars are common and people are used to picking up new intakes for a couple hundred bucks. Go look at what the LSx crowd is spending, makes me damn happy to still have a SBC haha. And talking economics, the LTx is the smallest of SBC markets.

BUT this is not to say you can't do it if you'll spend what it takes. Custom intake, exhaust, pistons etc.

So why does the LS get it? Because while yes, the SB2.2 and the like are becoming more affordable but the mass production of GM just leap frogs that price gap. They set out a short angle head as stock and what a hell of a building point.

It really comes down to economics and practicality. If you want 1000rwhp, use all off the shelf GEN 1 SBC parts and a turbo...done. So why bother with the other stuff.

I will say this, I'm probably going LS when I get the right chance...in a C4? I'm not so sure on that, I think 500-600 is probably the breaking point where you spend cubic money trying to keep the halfshafts and D44 together, which at that point, another platform makes more sense.

(Also, aren't the cathedral heads not as good as the tall rectangles now? I thought they went back to that with the l92s etc? I can't remember for sure.)

cv67

Very few out there would be willing to fork out huge bux for custom headers intake etc etc. to have the non 23 degree stuff on a street car. personally if I had the $ there would be an SB2 under my hood on the street just to do it

USAsOnlyWay

With the way LS motors are, thats almost the only reason now.

Doesn't change the fact that it would be badass, just not what one would do on a budget or without the right friends in right places at least.

cv67

Right about that bang for the buck LSx wins. Look at the new Lsx(???) heads from pace performance, killer numbers for the same price as a set of junk Chinese sbc Gen1 heads.

383vett

Here you go, 18 degree small block heads putting out 800 hp.

http://www.steveschmidtracing.com/dr...ree/dyno-chart

mcm95403

The basic SBC head was designed before most of us were born and really hasn't/can't change much if it's still going to maintain much interchangeability. The LSx engiens were just designed (on computers!) in the last 15 years and have all the benfits of millions of hours of R&D time, better machining, better base design, etc., etc., etc.

Just look at all these little 2-3 liter imports that make as much power and torque as a good V-8 twice that size did 25 or 30 years ago - while getting triple the mileage or more and emitting almost nothing out the tailpipe.

I bet the Flathead Ford guys were asking the same thing around 1960 or so......

93 ragtop

I wonder if back in the late 50's, Blueflame owners were complaining about why they couldnt make the power of the SBC?

C409

There's just one thing about progress ... it never stops !

mseven

there is ...and has been you just need to look in the right places. For example the 11* little chiefs flow over 450...(block requires a special lifter bore layout and cam).

here's a quote for you:

"The Little Chief head will SMOKE the SB2.2 head on an all out engine with a large bore ( 4.185 ) and two carburetors. The head can make an EASY 1000+hp on a 396cid engine. The little Chiefs valve train is not bad in comparison to the SB2.2. You have to have a special lifter bore layout for the Little Chief heads by the way. You cant just bolt them to a conventional lifter layout. I have done a LOT ( 70+ sets) of SB2.2 heads for a lot of different applications and they too, work very well. I would prefer the SB2.2 head for engines in the 358cid range that must utilize a single four barrel carburetor. I have converted a couple of land speed guys over to the SB2.2 heads from the 18s and 15s. The result was about 35 mph!

For an "all out" comp engine, The little chief heads would be my only choice for both single and dual carb applications. An " all out" 396cid engine with two carbs would make right at 1080hp."
Darin Morgan
R&D / cylinder head department Manager
Reher Morrison Racing Engines (from 2005)

If you're ready to step up to the big league, you can speak to Carl @CFE, without any doubt, I'm sure he can help you out...But be prepared, any of those type of offerings will be at least twice the money of any AFR head (not to mention the rest of the valve train parts, block etc. etc. ..which equals cublc $$$$$$).

The AFR head is an affordable choice and used by most normal guys, and will make good power. Even with that some think they are alot of money, but in that world they are a bargain. If money is not an issue there are options.

dizwiz24

A lot of responses have people indicating they want to go LSx.

Why would you do that if you could get the same level of performance out of your LTx or SBC by having the proper head/intake.

even if LTx parts cost 2x as much, it would still be cheaper and not worth the hassle of an LSx swap.

C4s are dirt cheap on the market. Even with LTx prices 2x more, you still could buy your c4 car cheaper than what you'd spend on an LSx platform car.

Id rather have a unique LTx car than the dime-a-dozen everywhere LSx powered GM vehicles.

My work truck has an LSx motor in it (5.3) and I dont think its anything special.

Bottomline point:

The LSx outperforms the LTx only because people let it and the aftermarket chooses not to support it as well.

USAsOnlyWay

True true, I'm not an LTx guy but there sill is some good support for the older vehicles. Hell we now have two vendors finally bringing us up to par with merge collectors and stepped headers as a production, non-special order, item. AFR is really bringing new stuff to the table to support the big CID builds we are using to be on par with LS motors.

What more do you want? Intakes, heads?

Why LSx: to try it, OEM dry sump, stock LS2 with L92 heads and headers and you'll make what my 383 does with better fuel economy and a broader power curve. These are mine, like I said, if I was going for all out power, I'd do a 355 with honkin big hairdryer.