When the Edelbrock E-Force supercharger first came out a few years ago, late model Corvette owners rejoiced at the fact that they now had a 100% bolt-on ready solution for boost that they could install in a weekend, and drive their car to work on Monday. Well, at least C6 owners rejoiced, since they were the only ones that could actually use the E-Force. But a few months ago, we reported that thanks to the engineering geniuses at Lingenfelter Performance Engineering, that was all about to change. Lingenfelter took on the task of designing an install kit that will include every necessary component to allow C5 owners to easily bolt the superb Edelbrock E-Force Supercharger unit to their LS1. Now the install kit is ready to start shipping, and we have been given the ok to give you our exclusive first look at how Lingenfelter makes it all possible.
OEM Components, OEM Quality
- Edelbrock LS2-style E-Force Supercharger
- Redesigned valley tray
- Relocation kit for oil pressure sensor
- New intercooler reservoir
- LS3/LS7 style water pump and radiator hoses
- MAP/IAT harness
- Throttle body extension harness
The E-Force Supercharger features the same Eaton TVS 2.3L four-lobe rotors as the supercharger unit on the LS9 Corvette ZR1. The lobes have a full 160 degrees of twist and allow the supercharger to achieve the highest possible volumetric and thermal efficiency with every revolution. On the E-Force the supercharger is inverted to allow for 12-inch long intake runners, which means more grin inducing low-end torque for you. Another unique feature of the E-Force is its integrated by-pass valve, which keeps you out of boost under normal driving conditions and your gas consumption down. But when you mash the gas, and the manifold goes from vacuum to positive pressure, the by-pass valve shuts and boost gets made just when you want it. Another huge advantage to the E-Force is the fact that you don’t have to plumb oil lines to the supercharger thanks to its self-contained oiling system that is good for 100,000 miles without needing service.
To get all the details on how C5’s will now be able to bolt on an E-Force supercharger, we spoke with Jason Haines, Project Director at Lingenfelter. As it turns out, getting the C6 E-Force to fit the C5 wasn’t exactly an easy task. Haines tells us, “Despite the similarity between the C5 and C6 Corvette, differences exist in many areas that impact the installation of a supercharger. The biggest differences are in the hoodline, cowl, how the accessory drive is set up, the sensors that have to be connected, and the general block design of the LS3 versus the early LS1 in the C5.”
Adapt, Improvise, Overcome
Haines explains further, “There are a lot of changes that we had to make to Edelbrock’s C6 E-Force kit, the LS1, and even the C5 itself to get it to fit. First we had to relocate the engine oil pressure sensor and modify the valley tray on top of the LS1. We also had to use a new intercooler fluid reservoir and convert the LS1 to a newer style LS3/LS7 style water pump and radiator hoses. Since the electronics are also different we had to use a new MAP/IAT adapter harness, MAF adapter harness, a throttle body extension harness, and even a new intercooler pump wiring harness. We also use a combination of a new hood and chassis spacers to get everything to physically fit in the C5.”
This particular C5 got the honor of being LPE's test mule for their E-Force install kit. As you can see, just like most other supercharger kits for the C5, you'll need a new hood to clear Edelbrock E-Force on your LS1. LPE has reworked their own C5 hood to work with the kit, and is working with other manufacturers to see if their hoods will work as well.
Now, we know what you’re thinking: “Great, I have to get a new hood painted…” But, when you really think about it, the vast majority of aftermarket superchargers for the C5 also require a new hood, so this is really par for the course. When we asked Haines about the aftermarket hood required he told us, “There was no way around it; the C5 Corvette requires a new hood to fit the C6 E-Force in the car. We revised the tooling on our existing C5 Corvette supercharger hood so that it would clear the E-Force kit. We’re also working with other C5 Corvette hood manufacturers to find out if their hoods will clear the E-Force system.” Well, I guess if you don’t want to buy a new hood when supercharging your Corvette, then you’ll just have to spring for a C6. But if you’ve got a perfectly good C5 you’d like to boost, then read on.
Fitting the E-Force on the LS1 called for a modified valley tray, and fittings to allow the oil pressure sensor to be relocated.
The LS1's water pump has to be ditched in favor of a C6 LS3/LS7 style pump and radiator hoses to work with the E-Force. LPE also had to design new intercooler fluid lines and a new idler bracket and tensioner.
In spite of the numerous external modifications required to fit the E-Force on the C5, the stellar Eaton-built guts of the E-Force remain the same. Per Haines, “The internals are unchanged with our C5 E-Force kit. We don’t make any modifications to the supercharger assembly itself. But, whatever shop the customer chooses to install the kit will have to make a small clearance modification to the back of the supercharger assembly to provide more clearance with the cowl. We also use the same air-to-water intercooler external radiator, even though we do have to modify it to fit the C5, and we even use the same water circulation pump. We do have to use a new intercooler fluid reservoir because the C6 E-Force reservoir just won’t fit in the C5’s engine compartment.”
The oil pressure sensor on the stock LS1 gets right in the way of the supercharger, but never fear, because LPE has the answer. Here is the oil pressure relocation fitting that LPE designed to work with the E-Force.
LPE had to use a whole new intercooler fluid reservoir on the C5, since the unit that comes with the C6 E-Force wouldn't fit under the hood.
We simply base our C5 adapter kit on the Edelbrock E-Force kit designed for the LS2 equipped 2005 to 2007 C6 Corvettes.
You keen eyed LSX junkies out there might have already been wondering how they got a supercharger designed for the rectangle ports of the LS3 to fit on the LS1’s cathedral port heads. We were too. You’ll be surprised to hear that they didn’t actually make any modifications to the LS3 E-Force… because Lingenfelter doesn’t use the LS3 E-Force. Instead, the guys at Lingenfelter
made the more logical choice to base their C5 E-Force install kit on Edelbrock’s stripped-down “tuner” supercharger kit for the LS2 (Part # 1595), which shares the cathedral port design with the LS1.
Per Haines, “To get around the head port differences between the LS1 and the LS3, we simply base our C5 adapter kit on the Edelbrock E-Force kit designed for the LS2 equipped 2005 to 2007 C6 Corvettes since the LS2 heads are cathedral intake ports just like the LS1 and LS6. They just don’t have the hollow valve stems that were in the 2002 to 2004 Z06 Corvettes with the LS6. We use the #1595 tuner kit since the calibration and injectors that come with the complete LS2 E-Force kit aren’t used with our C5 E-Force kit.” Now why didn’t we think of that?
Once you actually get the E-Force in place on the heads, this is what you can expect to see. There are still several lines, belts, sensors, and hoses that need hooked up at this stage.
Some Assembly Required
Lingenfelter plans to just sell their C5 install kit in component form so that customers can get the necessary parts a-la-carte, and only have to pay for what they really need. Haines tells us, “For now, the C5 installation kit is being offered as a fairly basic kit with just the primary components needed to install the C6 E-Force. The supercharger system itself, and the pulleys, fuel injectors, engine water pump, radiator hoses, throttle body, and fuel system are all available from Lingenfelter, but are being sold separately so that other Edelbrock distributors and installation facilities can source those components themselves if they want to.”
Here is a close-up of the 90mm electronic throttle body that LPE offers as part of the install kit. This is necessary since the E-Force is originally designed to work with the C6's electronic throttle body.
He adds, “Since the C5 Corvettes have been on the road for a while now, it’s pretty likely that the cars getting the supercharger system will already be modified, or might even be getting other modifications done at the same time as the supercharger system. That’s one of the big reasons it’s so important to offer the kit in component form, since some customers may not need the complete kit or may already have certain parts. If you don’t already have one, you will definitely need a high flow fuel pump, or at least boost the voltage to the stock pump to keep up with the fuel demands.” It may not be the 100% complete kit that C6 owners get from Edelbrock, but hey, you are a resourceful bunch of gearheads, we’re sure you’ll figure everything out just fine.
Along those lines, the Lingenfelter C5 E-Force install kit won’t come with a pre-packaged tuning solution like Edelbrock provides for the C6. But, if you’re doing this level of modification to your C5, chances are you already have a tuner in mind for your car, or better yet, you might already know how to tune yourself. Haines says, “Initially our C5 installation kit for the E-Force won’t include any kind of calibration, and it will be up to the customer and their shop to tune the engine after the install. At some point in the future, we do plan to provide a calibration delivery method as part of a more complete kit.”
Down to the Numbers
So now that we know what the Lingenfelter install kit is all about, let’s get down to the bottom line; how much power it makes. Haines tells us that with a 3.875 inch pulley, the E-Force kit on their otherwise stock LS1/6-speed C5 test mule made 9 PSI of boost. That much boost helped the C5 spin Lingenfelter’s Mustang Dyno to the tune of 454 horsepower and 437 pound feet of torque at the rear wheels. Not too bad considering that the E-Force is the only modification that’s been done to the car. Common sense tells us that just a basic set of long-tube headers and an exhaust system would likely net a pretty sizable bump in those numbers.
We were also curious if the Lingenfelter C5 E-Force kits will carry the same 50-State Emissions Legal certification and optional warranty that Edelbrock offers on the E-Force. Haines tells us, “Our C5 E-Force kit won’t initially be 50-state legal, but creating a 50-state legal version with the required calibrations is part of our product development plan for these kits. As for the warranty, the E-Force kits are available with an optional powertrain warranty that can be as long as 5 years and 100,000 miles, but that is only available for cars that are still under their OEM warranty. But because of their age, none of the C5 Corvettes will be eligible for the Edelbrock warranty.” Well, it was at least worth asking about, right?
Get a Check-Up First…
Finally, Lingenfelter strongly recommends that anyone planning to boost their C5 take the time to do a general health check on their engine and supporting systems. Let’s face it; most C5’s aren’t exactly spring chickens anymore and likely have some pretty good miles on them. Haines offered these suggestions; “One of the things we strongly recommend is that they also install higher pressure valve springs to help mitigate the potential for valve float at high RPM under boost. And finally, due to the age of C5 Corvettes, we recommend doing a general heath check on the engine and the vehicle before installing the supercharger system. When we install any package like this on a C5 Corvette we always perform a baseline chassis dyno test and an engine leak down check.”
LPE and Edelbrock have always had a great working relationship. Haines says, "Lingenfelter Performance Engineering and Edelbrock have worked together on several projects in the past, including the development of Edelbrock’s first cylinder heads for GM LS engine’s and CNC ported versions of those same heads. We look at the C5 E-Force installation kit that we are developing as just a continuation of the great relationship that we already have with Edelbrock."
To Boost or Not to Boost…
So there you have it. Every Corvette deserves the right to a big helping of boost, and now C5 owners can now celebrate the availability of a brand new, bolt on supercharging solution. Best of all, you only have to buy what you really need to get your C5 supercharged with Lingenfelter‘s new E-Force installation kit. While there’s a little bit of DIY involved, it’s good to have another proven option available when it comes to force-feeding your 5th gen Corvette.