I have a stock LS3 , a GM connect and cruise package (T56 manual), with the 480HP mid level hot cam.

With forced induction, does E85 offer any value here? I believe with the right tune and boost, 93 pump gas will reach the limits of this stock motor.

What would be the benefits of running E85? ignore fuel economy/fuel cost. Maybe less stress (boost, etc) on the motor for same power output or other?
I am struggling if i should upgrade the fuel system for E85. I dont plan on having the internals of the motor upgraded.

Thanks

 

You want to boost a 10.7:1 compression engine. If I were you, I would 100% run E85. You're going to be limited to around 10 PSI with that engine, and given that the bottom end is stock ( with hypereutectic pistons ), your margin for error is very small. I ran 93 on my forged 5.3 while I was breaking it in, and I tickled 12 PSI a couple of times. I'm running 10.5:1 compression, so that was on the ragged edge. As soon as I switched to E85, my engine ran cooler, picked up a ton of power, and was just safer overall. E85 by itself will add about 50-75HP to a boosted combo at the same boost level, and you'd be able to bring boost levels up significantly while running it. Not to mention power increases through additional timing. Aside from needing to upgrade your fuel system, there aren't many downsides to running it.

 

Thank you for the reply. Makes sense, will go that route and upgrade fuel system/injectors for E85. Running cooler and safer is a no brainer as you say.

I am going the supercharger route. At this power level (stock motor, street car, longevity is key ) with no intention on upgrading internals, is a smaller SC , say the LSA 1.9lL more optimal in terms of streetability, low RPM torque/HP vs a 3L whipple? Whipple has a nice inverted 3L supercharger. But it is 2-3x the cost of LSA SC.
And Wegener sells it with there front drive package.

Or i could go the more affordable route of a single belt system from CVF racing and LSA SC. About half the price overall.

Thanks again,

 

I've known a few people with 5th Gens like mine who have added an LSA blower and loved it. If you're not looking to go crazy, an LSA with a mild cam and pulley will give you all the power you want and then some. To me, the Whipple is a better option for a built shortblock with more cubes. I myself am a fan of turbos, but that doesn't make sense for what you have going on. I'd get the LSA, and if you decide you want more power, you can always upgrade. There's always a market for used superchargers.

 

I've never run E85 but a car buddy of mine has in their 6.0 turbo in a 89 Camaro drag car. They bought pump E85 gas and they tested it and at some stations it was E85 and other stations maybe E60? So buyer beware.

 

With E85, if you're at at least 60%, the tune isn't that finicky. You'll make about the same amount of power. If the tune is set up right, it will add timing as ethanol percentage increases, as well as change injector pulse widths to add or subtract fuel as needed.

 

Of note- That GM hot cam is a 20 year old design and not the latest and greatest technology. Personally I would swap to something with the newest tech/R&D while doing the LSA blower swap. The LSA blower is also quite a heat sink so make sure you have a good cooling system and when you do the heat exchanger you overbuild it plus put in a big reservoir for it. Those blowers pick up a lot of power from just a ported snout and larger TB.

 

Any recommendations for a cam?

And any thoughts on going the Whipple route. Have seen great reviews and performance on Mustangs but this Gen 6 whipple LSX version is a new product
I have been struggling to find a complete (or assembly of parts) LSA SC for less than 5k. Including reinforced brick. Not interested in Used stuff.

 

What exactly are your goals for horsepower?

If you're looking to make 600-650 horsepower, LSA blower and 93 octane with some good supporting mods will be just fine.
If you're wanting to make 850+, I'd go with at least the 3.0 whipple and E85.

 

What do you think the limits of the “Stock motor” are? How much power do you want?

You won’t be anywhere near where the motor wants timing wise with pump gas and any decent amount of boost. You’ll be severely knock limited well before that long block is tapped out. That’s the benefit of E85.

Whipple blowers also make a ton of heat and you are expending quite a bit of power to turn them. So more boost is needed to offset the losses…. Which makes more heat. Those blowers also make stupid power at low rpm that’s not useable for most, and hard on things bottom end and knock/tune wise. Which is why the LS9 came with a cam that basically neutered the motor below 5k. Which is what you want with that type of blower. You want a cam that really comes online at 6k+. It keeps the driveline alive and makes the power band more useable on the street. Esp if you run a street tire. They make no sense to me personally. You pay 5x the amount of a turbo kit and get less performance per pound and more heat to manage. They are great on tiny motors with limited power down low… like a 4.8. But slapping a big Whipple on a 480hp LS3 with a decent cam and pump gas goals seems like a waste of time and money. Much easier/cheaper way to spin tires.

 

Seems like a bad idea when you breakdown the cost per HP and all the other unique issues that come with blowers like this, excessive heat being at the top of the list. You can't just turn it up whenever you want because there's no boost controller. I was contemplating going with one of these units before I decided turbo was the way. Just looking at blowers makes me feel like I'm spending money

 

Lol. Yes. It's adding up. I want to do this work myself. I am a weekend warrior and blowers are more bolt on and suit my abilities. That journey has value to me.

But at my hp objectives, say 750 , the lsa would be the most cost effective. And could get there on 93 gas alone . But will build for e85 as well.

And prefer the quicker torque response over turbo. This is a street car and it will be very rare i run over 6k rpm

Thanks for the reply. Newbie here still learning.

 

Don’t get me wrong, those blowers are cool. They make all the right noises and basically turn your LS3 into 800ci mountain motor. It will be violent and make an unusable power band for an average street car. Won’t be anywhere near as fast or “streetable” as a turbo setup.

Your turbo worries are mostly newbie thoughts/myths. All the power adders could get you to 750 on 93 gas alone. That blower is about the furthest from cost effective there is! It’s also the least efficient, as it will take more boost to hit the same power goal! Gotta remember it takes HP to drive a blower. Also that design is less efficient than a turbo at compressing air. So you lose like 15-20%+ of your power due to heat and power draw to turn the thing. So you’ll have to run 2-3psi+ more boost to make the same power at the wheels as a turbo setup would.

The lag myth is very application specific. You are only wanting 270ish additional HP. That’s like 8-10psi with a small frame turbo on that motor. Size the turbo correctly with the correct converter and there will be zero lag.

You don’t want 600+ftlb at 3000rpm. It isn’t usable on the street and its really hard on the motor. Low rpm and big power breaks things. Your motor would be MUCH healthier if you cammed it to make power to 7k and brought in the majority of the power progressively after 5k. That’s impossible to do with the blower you are looking at.

As an example with a dedicated ladder bar drag car, I was pulling TONS of power with a 30” slick on my turbo 4.8 to get it to hook on the street. Down to single digit timing for 3 seconds on the launch and not even activating the boost controller till 60mph to get it to hook. Instant power at low RPM is useless on the street past a certain point. Esp. on any sort of street tire. Once you hit the point you can spin the tires, adding more power makes you slower.

Just a thought anyway. Either would be a fun.

 

100% you should run E85. Wire in a flex fuel sensor . It's not hard to do. I've personally seen LS3s put down over 700 rwhp on the Dyno. Keep in mind you need to Gap your rings for boost .