(Another) GPI Max Package teaser - this one with traction!

[1JEWLDSSRS]

Originally Posted by acammer

Never. Ryan's far more committed to going fast that I ever will be. His car represents the true EDGE of max effort stock bottom end, everything about that car is on purpose to do one thing, go faster at the drag strip. On the other hand, he's made himself a full on racecar, it's not something you'd drive across the country. I DROVE my car 1,200 miles from upstate NY to Jacksonville Arkansas, we installed the Max Package 2.0, and then I DROVE it 1,200 miles home 5 days later. If that's not a validation and a testament of the product's reliability and driveability, I don't know what is!

So, I don't have plans to do the weight reduction, auto trans stuff, drag brakes, wheels, etc that it takes to be truly fast. This car, as it sits at 4,100lbs today, probably is still gonna be tough to wrangle a 10 second pass out of, even with all this power. If we dropped this powerplant into a committed drag car with a TH400 and a sub 3500lbs race weight, it would go mid-low 10s on the first lick down the track and have a shot at work it's way down into that 9.99 territory.

Wow! That's totally awesome that you were able to drive all the way over and back after the build! Really does say how nice and reliable the package is. Very well done. And yea, I was only kidding about Ryan's car, I knew it was a full on track car. Just wanted to see what you thought. You da man!! And GPI rocks!! Thanks for ALL you guys do for the Camaro performance guys.

[Bob570]

Originally Posted by acammer

You're correct- we're turning some pretty good RPM with this setup. Peak power is coming at 7000rpm, and then the curve beyond the peak is very favorable, we're only down 30whp by 7700. So, the shift point target is 7700rpm, which gives us decent shift recovery into the next gear.

I've got a valve-train setup that should be very solid and well controlled out to 8000rpm+ as a little buffer for over-revs and all the stupid stuff that happens when the TCM doesn't get the shifts right. In this case, the TCM in this car is the computer between my ears as this is stick shift, it can be very unreliable.

The valvetrain is Johnson ST2116LSR link bar short travel lifters, Comp XD-A adjustable length push-rods, Comp BSR Max Lift shaft rockers, and PSI 1513 valve springs. It might be approaching overkill, I have a soft limiter come on at 7700rpm, and the hard limiter is 7800rpm. But on the other hand, if you miss a gear and give this a determined throttle stab you're NOT stopping at the limiter, the acceleration and inertia is going to take you easily to 8000-8200 depending on how quick you get out of it.

Without giving away all the upcoming release details, let me tell you a bit about the "Max Package 2.0". Years ago we used to offer an LS7 heads/intake and cam setup for LS3/L99 cars. It worked very well, and would make a little more power than a good LS3 heads/cam car. But it had some compromises about it that we weren't totally satisfied with. So, we redesigned it.

The new version, we're calling it Max 2.0, uses a Brodix BR7 casting (aftermarket LS7 head) which we do our own finish work on to set the port size/profile, and valve sizes to what we think is about perfect for the bore size of an LS3. It's a 12* valve angle, which helps us run both more camshaft and less combustion chamber (more compression) than you can with a stock bottom end and LS3 heads. 1.8 LS7 style rockers, LS7 ports, all the goodness of that head design but for the bore of an LS3.

It pairs with a few different LS7 intake manifolds, we have the LSXR on my car, but a hi-ram is always an option, and an MSD Atomic can be made to fit with a little clearance on the manifold. 103mm TB is the way to go with any of those manifolds.

Using the LSXR intake and simply bolting it on should make about 10% more power than a SS4 NFC/ported LS3 heads/stock intake car. Flycutting to add some more compression and then running a hi-ram can take power levels up substantial more. It's more costly that a cam and set of ported stock heads and intake, as any time you get right out on the edge of truly max effort stuff and diminishing returns, you're paying more for those last bits of performance. For the guys looking for max effort NA stuff in a true bolt on package without touching the bottom end, it's a killer option.

Sounds like a badass setup.

I wonder if you could mimic the results of the Hi-ram by shortening the runners in an MSD by an inch or 2, a lot of the C6Z guys have been doing this, although those guy have a much bigger displacement, so maybe it'll push the powerband too far up for an LS3? Just thinking out loud.

I can't wait to find out more, I was interested in your Max Package 1.0, knowing you guys, 2.0 will certainly be even better!

[acammer]

Originally Posted by Bob570

Sounds like a badass setup.

I wonder if you could mimic the results of the Hi-ram by shortening the runners in an MSD by an inch or 2, a lot of the C6Z guys have been doing this, although those guy have a much bigger displacement, so maybe it'll push the powerband too far up for an LS3? Just thinking out loud.

I can't wait to find out more, I was interested in your Max Package 1.0, knowing you guys, 2.0 will certainly be even better!

We run the FAST LS7 LSXR for the "under the hood" option on the Max 2.0. The LS7 version of the LSXR gives us about the same performance the MSD Atomic Air Force does, and it fits better, so it's the winner in our eyes. The LS7 version of the LSXR does not have the variable length runners that the LS3 version has. However, you can modify the LS3 runners to work. So, to your point, it is possible to do a mid or short runner under the hood with a plastic manifold. I don't think the results will be quite as good as a high-ram, but you'll get a similar effect.

Also to your point, it's going to shift the power-band up substantially, and depending on the combination, that may not be desirable. With the standard length runners mine peaks at 7,000rpm, and holds on really good out to 7,800rpm. It's a stick car, so we need to basically rev it as far as we feel comfortable to help with shift recovery. We've got a good valvetrain for that, but to do much more than we do now, we'd really need to go solid roller. A shorter runner like a hi-ram is probably going to see the peak in the 7500-7700rpm range, which would mean 8500rpm shifts in a stick car. Even an automatic would want to turn it to 8000rpm or so. Doable, but depends on what you really want out of it. I wanted to stay hydraulic roller, and have a safety factor over the shift point just in case dumb stuff happens - it inevitably does. So, long runners were the obvious choice for me - and it still turns a bunch of RPM.

You're right on, the bigger cubic inch motors will tame the RPM back down a decent amount, and that makes the short runner stuff more viable for hydraulic roller combinations in that 400+ci range.

[morepowerjoe]

Really cool Andrew! I don't know if you can answer this or not but what stall would you need with this set up?

[Ashen L99]

How about an mg9 out of a zl1 with the awesome 5th?

https://www.facebook.com/marketplace...9669304401824/

Would the max 2.0 eat nitrous?

[acammer]

Originally Posted by morepowerjoe

Really cool Andrew! I don't know if you can answer this or not but what stall would you need with this set up?

A 4,000rpm stall would be appropriate for this when using the LSXR manifold. We nearly the power and torque that the existing SS3 and ported rod mod manifold setup made from 3,000rpm to 4,800rpm, and then the Max Package starts to separate itself. By 6,000rpm, its way ahead of the old SS3/rod mod setup, and makes a really long, flat curve out to 7500+rpm, it's a much fatter overall power band.

I have a great dyno overlay that I'll be sharing soon. When we tested this, the SS3 and ported rod mod combination put down a super stout number - so much so that we were almost a little concerned about how well the max package would compare against it. But, it did not disappoint!

[acammer]

Originally Posted by Ashen L99

How about an mg9 out of a zl1 with the awesome 5th?

https://www.facebook.com/marketplace...9669304401824/

Would the max 2.0 eat nitrous?

The MG9 would be AMAZING for the 5th gear, but the overdrive sucks. And, I'm going to a 4.63 rear end, which will make it suck even more. If I did a bunch of roll racing where I needed to make the 4-5 shift, it would probably be a big consideration, but I really am trying to very casually take this car in the direction of "drag and drive" so I want to keep all the cruising niceness that I can. The MM6 has the closer 1-4 ratios, and the fattest TR6060 overdrive out there, so I think that's the move for me. Probably will go to a lighter flywheel as well, to try to help with the high-rpm shifting, the motor just doesn't wanna shed the RPM all that fast.

Max 2.0 will LOVE nitrous. It's a 6 bolt casting with a hugely thick deck surface, so it's well positioned to be used on big boost or spray applications with aftermarket blocks that use that extra set of bolts to help keep the heads sealed up. The LSXR manifold also has bosses you can drill out to add a port injected nitrous setup for perfect distribution. I'd be lying if I told you I haven't already been thinking about how a 200 shot would feel...

[Chris49066SS]

That thing sounds great!!