I am about to get a cam, heads, headers and intake on my c-7 grandsport. Shop also wants to install a flex fuel kit.
After doing some reading, forced induction makes more power with flex fuel kit, not as much on naturally aspirated. And I can only get the E85 at crappy fuel stations.
So I am asking the group does anyone have it on their naturally aspirated vette and really like it??

 

I did the flex fuel sensor on my NA & love it. CAI, ported TB, ported MSD Intake, Kooks 1-7/8 LT's w/ X-pipe & tune added 85+ hp. on e-85. I'm at 486hp at the wheels spinnin' on the dyno. Added a Fuel-It ethanol sensor to monitor the E content & I'm running 70% E pretty consistently. Best $230. for hp gain I ever spent. I did some other stuff, but pretty sure it didn't affect HP gains. (Wires, plugs, coils, etc.)

 

First mods to mine were headers ,intake and flex fuel. Loved it. Got me to 470 rwhp. Went with a blower so then fuel system naturally couldn’t keep up so had to lose the E. Upgraded fuel system this year and got the E back. Really missed it especially the minimal fumes.

 

i recently added it to my car, gained 17 whp and 22 torque, best thing about it is you can run any combo of fuel. i did the dsx sensor and the fuel it analyzer.

put me a 499.43 hp and 485 torque

 

E85 is well worth it, typical N/A gains are 20-30 HP at the wheels.

Why do you think the E85 is crappy, just because the gas station isnt a top tier station?

 

Yes, I work for Shell and have made gas for the last 23 years. The racetrack stations don’t add any additives to the gas.
but sounds like I can still run 93 with the flex fuel kit so a tank here and there will satisfy my taste.

 

the valero by my house is regularly E71 according to my analyzer, about every third tank or so i fill up with 93. some people hate the smell of the exhaust on e, i personally love it

 

As everyone has mentioned, E is a great way to gain power and reduce the likelihood of knock. Easy upgrade for an NA car. Gains are dramatically better on a boosted car, but upgrading the fuel system becomes mandatory at that point though.

 

Upgrading the fuel system will depend on the car, the fuel system and the goals. I have a 19 C7Z, I can run E60 with zero mods to my OEM fuel system.

 

A flexfuel sensor is by far the best bang for the buck bolt-on for the LT1 or LT4 and should net you 30-40 rwhp for under $1500 including the tune and install. The sensor itself is like $300 and installation isn't terribly difficult for a decent shop. I'm not sure I'd even bother with head/cam if I were you but that depends on your goals. Without the cam you should be around 485 rwhp on E85 with the headers, intake, CAI and a decent tune. There's several LT1 guys in the high 10s with that combo.

If you decide to go the blower route later you will probably want a different cam grind compared to NA so may want to keep that in mind. You'll also need to upgrade the fuel system if you want to continue running full E85 (or add meth) depending on how much boost you want to run which will cost you $5k or more on top of the blower cost. Your LT1 doesn't have the fuel system of the LT4 and, depending on boost, you likely won't be able to run full E85 with the LT4 fuel system anyway. 99% of the LT4s with headers, pulley, and CAI tap out at E40 without a cam and/or low-side or meth and that's right around 700 rwhp which is about the most power you can get from an LT4 without fuel mods.

 

All good stuff!

 

This really depends on the year of the C7Z. On my 17 Camaro SS 1LE I put the full LT4 full system in that car (had the LT4 LPFP from the factory, I added the LT4 HPFP, injectors, and all of the LT4 fuel lines myself) and ran the car was able to run E50 on the stock cam. My 19 C7Z has the ZR1 low side and then the normal LT4 high side, so far we are seeing up to E60 with no issues at all. With that I stopped add all of the normal bolt on's other than headers.

 

You are running on the ragged edge at E60 imho based on your previous posts, TJay. I could see E45-50 without headers on your setup, E60 is a stretch for me unless you are at altitude. The year of C7 Z06 doesn't really matter, we all max out around 700 rwhp without meth or other fuel mods, and here's why:

The 20% higher flow from the ZR1 lower we have in our 2019s (I have a 2019 also) obviously flows more fuel but GM didn't augment the HPFP in the same fashion because they use SPI on the ZR1 so the fuel issue just moves to the HPFP on our cars, which still isn't going to support more than 700 rwhp. You can shore up the HPFP with a cam, SPI kit, bigger pump/injectors, or meth. But then the issue will ping-pong back to the low-side, you'll have to augment that, and the ping-pong game continues between high-side and low-side until you are happy with the car, run out of money/patience, or you permanently fix the issue with something like SPI. With my 19Z the low side is still fine at E40, and probably would be fine at E50, but the HPFP started to drop under 2900 psi at E40 so my tuner recommended I keep it under E35. My run at E40 was right at 700 rwhp. E32 was 685 rwhp and the car is a hand full on the street from a traction perspective so I don't miss that 15 rwhp knowing the car is very safe at that number. If I ran the car on the drag strip a lot, the tenth I'd gain at E40 might be worth it, just not so on the street imho.

If I were you, without headers, I'd stay at E50 or below just because there isn't much HP difference between E50 and E60. You get 90% of the full pump E85 gains at E50 so, unless you really don't want to mix at the pump, E50 is a great target on the LT4 cars power-wise. It costs a lot of money to shore up the fuel system to run full E85 for very little gain compared to E50. E50 was my target too but the combo of other bolt-ons I have added too much hp to get there. If I dropped the headers or pulley I could probably run E50 safely though, like you.

On a car like the OPs which started life as an LT1, for now, I'd do the bolt-ons mentioned minus cam/heads and add the flexfuel sensor with a tune to run full E85. See where you end up and how you like the car. If you want to supercharge it down the road, I'd do the cam/heads at that point. That's a much bigger expenditure so may not be worth it to you.

 

I guess we will have to agree to disagree, all of my data logs are showing anything I should be worried about are perfectly fine.

 

I'm curious, with all the people running E-85 in their LT1 and LT4 direct injection engines, what injector pulse widths are you running? The highest I've seen is about 6 MS.

 

I got lt1 procharged with meth and lt4 fuel system and Dsx lowside at 10 psi. E75 I’m at round 5.2.

 

It was my first mod on my C7 and for the cost it picked up 33 rwhp. However, the best pick up was in the 1/4 mile. Bone stock it went 12.06@116, with the addition of E85 (E70) we went 11.58@120. No other mods at all, ran drag radials with it bone stock and the same drag radial with E85. Spent under $800 including the initial tune. My injector pulse width was averaging 5.0 to 5.2, low side was usually around 50 psi going thru the traps. We tried running higher E amounts all the way up to actual E85 (C85) and there were really no gains found on the dyno or at the track. So we stayed with just regular E65 to E70 at the pump. Maybe it would be a benefit with more mods but after we added long tubes, ported msd and 95mm tb we were able to get the car to run 10.91@128 in not so good conditions with DA in the 2800 range and temps in the Mid 80s.