That is serious right there!

Since we are discussing ports. How do the C5-R heads fit. Aren't they still a cathedral port, and do they bridge the gap between square/cathedral port? Also why the GM move to square port if cathedral is a better street head? Was the 6.2 LS series deemed to produce enough torque through displacment that the square port could be effective?

 

^ GM has a lot of other things to consider; cost, NVH, emmisions, fuel economy, etc... I'm sure they did made the transition with hundreds of aspects in mind.

 

Also, a smaller port that flows similar air to a larger port requires alot more refinement and attention to detail (CNC porting costs would likely be incurred....too difficult to nail in an "as cast" port).

That's not the direction a major manufacturer wants to go in a high volume piece unless they are targeting a higher priced vehicle.

Back in 04' GM was pimping how much better the C6 oil pan was over the batwing C5 design. PLEASE....anyone with half a clue would realize if you launched the car hard with the new C6 designed pan half of the oil reserve in your sump would be wrapping around the crank and all over the last four cylinders of the engine (it's an open pan essentially with vertical baffling). For those wanting better clarification and pics of this scroll back to the earlier part of this thread where I posted some pics of the tray I fabricated to cure that situation.

The bottom line is GM didn't really swap to the LS2 pan because its truly better for the Corvette enthusiast about to drop some serious coin on a new C6.....they swapped to that pan because it probably probably knocked the cost of that component in half conservatively. Not every move the OEM's make is about whats truly best for the consumer.

The most ridiculous move they made was installing the square port heads in truck applications.....a 270 cc head is not the answer for towing a trailer up a grade I assure you. Our 205's (or something similar) and a long runner FAST intake would make that truck feel a thousand pounds lighter!



I love that icon....thought it was semi applicable here!!





-Tony

 

That's awesome man! Bet it came with a heavy price tag.

 

can your vette rear end handle that much power ?maybe get a 9sec legal chassis thats already built for that much power .

 

Tony are you guys going to make a plastic single plane manifold for the LSX ???

 

Im in the middle of taking care of that as well....

With the results of this effort actually better than I anticipated (and knowing even what I anticipated was on the ragged edge of any type of reliability), I have decided to move forward with the installation of a C6Z06 driveline (the same rear/trans set-up thats in the mighty ZR1). The rear housing and ring and pinion is MUCH beefier than a C5 or standard C6 set-up but requires the installation of the rear cradle from a C6 and some exhaust modifications to clear.

Here is a pic of the set-up I just purchased which should arrive in CA any day....



BTW, for anyone reading this looking for an upgrade in their C5, Im selling a built 373 rear, a built 3.90 rear, and a tranazilla T56 (the baddest T56 in regards to torque capacity....I think its rated at 1200 HP and 900 ft/lbs).

The Transzilla in my C5 now would have been more than adequate but the rear of the C6Z doesnt easily bolt up to it so Im selling all my C5 upgraded driveline parts (PM for details if you have an interest).

This motor/driveline install represents a large endeavor both financially and in regards to time and labor required, but at the end of the day, there will be few cars on the road (normally aspirated especially) that could produce similar performance figures. You would have to spend seven figures in an exotic to get close and even that list is a small one (I think the Bugatti Veyron and one or two others are capable of high 130 traps or better).

Looking forward to next months re-dyno....especially looking forward to my first drive (but that's many months away unfortunately!)



Cheers,
Tony

 

So if we are to assume that the cathedral heads are superior in street trim, but more expensive. The air requirements of the 6.2+ engines needed more than the catherdral ports were able to provide at a reasonable cost. Therefore, they went to the bigger square ports to get the flow required at the desired price point.

Also, is the C5-R superior to all other heads, given a similar amount ot work.

 

Perhaps a better way to be more "political" and saying the same thing is a cylinder head design with a smaller port that flows similar, or better in some cases, than a much larger port (and in the case of the cathedral LS) coupled with an efficient long runner intake, will provide spectacular results in a street/strip application with the obvious perks of the high speed/high inertia design adding to the "street" side of that equation very handsomely (better response, low speed torque, less reversion issues, etc. etc.).

If we are discussing LS engines then we are certainly making a case for the cathedral port design....if we were discussing big block Chevy's we would be making a case for the modern clean sheet design oval port heads (versus the larger rect port stuff). You get my point....the same argument/situation can be applied to various families of the V8 engine....its not just relevant/applicable to the cathedral LS engines.

The C5R head you mention....very efficient design with its flat valve angle, raised intake runners, modest cross sectional area, but kind of a completely different animal....more aimed at an application that has a much higher air demand and no restrictions in engine height. Sure....ultimately it has the potential to make a bunch more power but it is likely to be coupled with a single plane (short runner) intake and a solid roller to turn more RPM to better utilize its airflow potential. Is it really better in most of the vehicles that people reading these threads are targeting? Probably not as they are engines meant to package under standard or close to standard height hoods, and most of which will be equipped with a hydraulic roller and cam timing benefiting a 3000-6800 RPM range (some even less).

Its always about the right combination and the right combination to fit the right application.

The C5R is a really killer race head.....I just don't think alot of it applies to the LS1Tech crowd (perhaps a tiny percentage). Does it have more power potential than the heads on the engine featured here (a Mamofied set of AFR 245's).....most definitely, but would this entire engine need to be reconfigured around them.....most definitely as well. My goal was a very powerful engine that would package like a stock engine and look no different under the hood than what could be a highly detailed 346 with a black painted FAST intake. Plus, I wanted an engine that would deliver the bulk of its grunt by 7000 RPM or so to keep a cam with reasonable street manners in the picture.

Building/designing high performance engines are loaded with compromises and decisions coupled with more compromises and decisions....
Steering your way thru the maze to end up with an engine that can produce the power you want, be able to bolt in the car the way you want (not cutting a hole in the hood for instance), with the manners/drivability you want, and lets not forget the budget you want....at the end of the day making ALL of that happen is the real trick and it usually requires compromising some of the goals or the funds necessary to get there (the less the goals are compromised the more the funds usually are!!).

Amen....LOL



-Tony

 

Some very good answers Tony. By the way Tony can one get an AFR
210 competition head with the AFR 195 competition exhaust port? I don't want to change headers.

 

Thanks for the info. Makes thinking about how they compare a lot easier.

 

We wouldn't normally do it....LOL

Can I walk something thru the shop like that....maybe.....would have to get my Production Mgr on board as well.

I know you have always been vocal about your success with our product and I would like to help you. If your serious about this new head at some point pick up the phone or shoot me a PM and we can discuss it.

SSCamaro....glad to have helped you sort it out in your head a little more. The C5R is undoubtedly a very high end, very capable piece, it just doesnt package well and make sense as much if we are discussing a hyd. roller 7K or less street/strip machine.

The right tool for the job is a phrase that probably makes sense and applies here. IMO if we are discussing the configuration I highlighted above (pump gas hyd. roller 7Kish street/strip car), the right tool appears to be a really well set-up cathedral configuration.....and if the current manifold project I am developing and plan on testing my next trip to the dyno pans out half as well as I suspect it can, that seals the deal even further.

Good stuff....I'm almost as excited going back to the dyno as I was before I first tested this combination....and I was pretty pumped up then I assure you!



Cheers,
Tony

 

Thanks Tony. I will wait until after my next dyno pull in about a month to see what I am going to do. I will PM you from here on in. I have a one off custom set of headers fitted to the 195 heads.

 

Info on this please.....

 

Awesome build!! It's amazing how the hp/tq curves are almost identical between the 2 engines. Taking very different engine combinations and making it "behave" very similar with a LOT more power output... amazing!!

 

I don't........ haha such a beautiful engine!

 

awesome build

 

Excellent Build Mamo...and good result

 

Nice build Tony. Looking forward to the final results. Maybe another video is in order. I'll see if Harrison is available....

 

I sent you a PM regarding something else about a week ago, with contact info. Might be interested in a rear if still available. Wouldn't be right to post in here without saying, awesome build Tony . Hope to hear from you.