Josh B.

Edmundu, a forum member, was very helpful with helping me get setup on the flex fuel.

Here is a DIY I put together for my local Corvette Club:

For anyone considering flex fuel for a C6 or C7 Vette, it's a very straight forward process. E85 is 85% ethanol, 15% gasoline. It has a motor octane of 105. In addition to it's high octane rating, E85 will lower inlet charge temps on both Naturally aspirated and forced induction engines. Typical gains on stock N/A cars that switch from pump gas to E85 are in the neighborhood of 15-20rwhp; 25-30rwhp on HCI cars. Forced induction cars will benefit even more, regularly gaining around 50-100rwhp. The cooling effect of injecting ethyl-alcohol into your engine will reduce coolant temps around 10 degrees.

Pros:
More power
Less carbon build up. Your engine will look like it was cleaned with brake cleaner.
No more detonation
E85 is a renewable resource. Because America.
E85 costs less than 87 octane and is federally subsidized.
Exhaust will smell like moonshine
Also, more power
The Cool factor of enabling a secret capability within the factory computer that GM decided not to activate on the Corvette but did so on many other GM passenger cars and trucks with the exact same ECM.

Cons:
Availability. Biggest drawback, closest location is Montgomery, AL
Cost of bigger injectors/pump
Less range, 25% less fuel range
Worse mileage, but it costs less than 87, much less than 93, so it's a wash in the end
It's bad for your injectors if you park your car and never start it.

A drawback to E85 is that it has less chemical energy per volume than gasoline and requires 30% more volume in order to properly burn at the correct stoich. 30% is alot of fuel, so plan on larger injectors and a larger pump/lines in order to support the addition volume. Gas mileage usually takes a hit as well, typically about 25% reduction or so.

There are two options for converting a C6 to flex fuel; buy a $400 kit, or piece together your GM parts yourself for a total of $124.72.

If you have $400 and want the very best quality hardware, invest in a flex fuel kit from Dedicated Motorsports. Here is a link:
https://www.dedicatedmotorsports.com...ct_p/c6ffk.htm

If you are willing to piece meal the parts together for one third of the cost, here is what you need:

Parts List:
(Only includes what is needed for Flex Fuel, you will likely need injectors and a pump or BAP.)

-Sensor - part#13577429 $35.77
http://www.ebay.com/itm/142041070558…

-ECM wire w/pin - #13575575 $8.43
http://www.ebay.com/itm/122092411893…

-Sensor Pigtail - # 13352241 $13.00
https://www.amazon.com/Genuine-GM-Ha...=sr_1_3…

-15'(Black,White,Pink/Blk) of Automotive TXL (22-26ga) Wire. You'll need 3 to connect sensor,power and ground.

-Abrasion Resistant Wiring Tape

-(Qty 2) Quick Connect Fuel Rail Line Adapter Fitting LS LS1 LS3 -6AN to 3/8 Hose GM, AN808-02B $21.90
https://www.amazon.com/…/B01…/ref=oh...o02_s00…

-(Qty 2) Straight -6AN Twist Lok Hose End Slip Fit Push Lock Black 6 AN Flare 8010-06B $17.90
https://www.amazon.com/…/B01…/ref=oh...o01_s00…

GTO EFI SS Line - #651120 $27.72
https://www.amazon.com/…/B00…/ref=oh...o03_s00…

Total $124.72

How to info:

Pin Location: E38 pcm - X1- Black Harness Connector....Pin #40.

You'll need to remove the right front wheel, splash shield, and loosen the front fender bolts behind/under the splash shield. This will give you just enough clearance to get your hands in there, to unbolt the PCM, and then rotate it down to where you have some room to remove the connector. There are little tabs on the connector that will separate the 2 halves, and allow access to the #40 pin. You'll need to push out the knockout plug. This can be done with a small pick, starting from the inside of connector going outwards. Then just orient the pin to match the others and click it into place. This is the toughest part of the job. Put everything back together.

Now, you'll run the wire over to your flex sensor, use something to protect the wire, be it tubing or tape. The sensor will need a switched power source. Black wire to ground. You'll be cutting off one end of the sensor pigtail, and splicing you wiring in. Done.

Now connecting up your fuel lines. If you have the above, you use one efi connector to existing firewall line. Then use the short 4" AN line to connect to the other EFI connector. Then connect this assembly to one end of the flex sensor. On the other, use the GTO ss line to complete the loop to the oem fuel rail.(If you are using billet rails, then you would use whatever combo of AN lines/fittings works for you.)

Here is another great source of flex fuel swap info, it's a G8 forum, but the ECM and hardware is almost identical to the C6:
http://www.g8board.com/…/154714-writ...-fuel-s…
Remember, flex fuel means you can pour in any mixture of E85 or pump gas and your computer will automatically compensate your tune and your car will absolutely run correctly. So you don't need to run E85 ALL THE TIME in order to reap the rewards of these small parts, the potential for more power will always be there for whenever you get your hands on some corn gas. In addition to the parts above, you will need a professional tune that enables flex fuel, in addition to possibly larger fuel injectors and a larger fuel pump. Stock C6 corvettes have some room to grow on fuel supply and could ostensibly support the fuel volume reqired for E85. Thanks to Andy Popple for helping me find E85 in the area. Andy is a resident guru on E85, his car burns it by the barrel!

C5 Hardtop

Nice pictures. Dig the bokeh on the machined parts

Post up a vid when your done. I'd love to hear it.

Josh B.

Thanks man! You know, sometimes I wonder to myself if I'm the only one who cares/notices about proper focusing, so I'm glad to know I'm not crazy. I'll definitely post up a good video.

Rob's car just got a solid roller and it sounds like the best cammed LS7 (or LS anything) I ever heard.

Here's his idle clip:
https://www.youtube.com/watch?v=EVOuaCnoT-o

double06

This is going to be an awesome test/build and I think it will shed some light on a few things people are interested in doing to their cars.

Bad_AX

Wow, looks like you're going for a SERIOUS max effort NA build. This is almost an Engine Masters class build with the valve train specs. Are you doing anything with the bottom end other than the ARP rod bolts?

Josh B.

Thanks man, those engine masters builds are mind blowing! Because it's a SR valve train, the cam specs become a bit less wild once the lash is subtracted. My goal is to just try and improve upon the combination. Tony Mamo spec'ed the valvetrain, the cam, the MSD IM port work, and obviously the cylinder heads. I respect Tony and asked if it was ok to share info/pictures. He was very supportive of sharing all the specifics.

The bottom end has ARP main studs along with an Improved Racing Crank Scraper and Windage Tray, studs are required to fit those parts.

RobGOV-DCZ

Josh can you comment on your Meziere EWP.... Coolant temps before/after, any issues blowing fuses etc, horsepower gains before/after?

Thanks!

Josh B.

I have been daily driving my car for over a year and the Meziere has been 100% reliable. I forget it's even there. And when I tell even close car friends I have an EWP, they are surprised. It's extremely quiet, and utterly reliable, so it's easy to forget it's there.

I wish I did proper before/after pulls. I made 620rwhp/523rwtq STD on Vengeance Racing's dyno. A couple months later I installed the EWP, changed dynos, and it pulled 584rwhp but the same 523rwtq SAE
Both dyno's are DJ 224x models.

There was a bit of a learning curve with the thermostat. I could not for the life of me properly bleed the system without drilling a hole in the thermostat. Coolant temps would spike, then drop like a rock. I drilled two 1/8" holes in the 180* thermostat and thoses issues absolutely went away! Another problem arose, with two holes in the thermostat it took much longer to reach full operating temp in the morning. I haven't fixed it yet, but I'm putting in a new (same part #) 180 thermostat and just drilling one 1/8" hole, so that it bleeds air, but doesn't flow too much coolant when the stat is closed in the cold.

Overall coolant temps are lower everywhere, and absolutely stable. The stock WP would fluctuate a few degrees. The Meziere doesn't fluctuate. I get an operating temp around 194 and it just stays there.

High speed driving: I've done 60 mile "cruises" through the Alabama back roads with my vette buddies, plenty of WOT pulls, and the ECT never went higher than 200. I credit much of this to the Dewitts radiator. I wish I knew what a 30 min HPDE event would do, but I haven't tried one yet. But if my WOT driving for long periods is any indication, the Meziere should be very capable of meeting the coolant flow requirements.

I have never blown a fuse. I used a nice SPAL relay I had leftover from a previous build. The only hiccup I ever have (happened) twice, is when I disconnect the EWP to tune the car (since key on runs the EWP and drains my Braille battery). The problem is when I forget to reconnect the EWP afterwards. I'll get 2 miles down the road and my instrument cluster tells me I'm retarded. Pull over, plug the harness back together, coolant temp drops back instantly.

It's an EXTREMELY well-engineered unit, and very suitable to daily driving. Hopefully it was worth 7-10rwhp, but I'll never know.....

double06

You ought to look at that SAM 820 HP build, you will note they did dome stuff (smoothed edges etc.) on the vent windows on the lower part of the block.

FRiCK916

Sub freakin scribed

Awesome sir. C'mon 675rw.. lol

Bad_AX

Hard to believe they make that kind of power with .641 max lift. Duration is REALLY wide, and it's not for street driving at all.

Josh B.

Rock on man! 675rwhp would be pretty awesome. I got to 163mph at wannaGOFAST last year. I'm hoping to one day break 170mph NA, privateer. It would be great if the LG Super Ram Air adds a mph or two up top.

AzDave47

Josh, On the DeWitts radiator with IOC and ITC on my K501 HCI build on a 1.2 mile track with ~125 MPH max and lots of slow speed driving (but 4-7K RPM) 100-106* air temp I saw 245* water temp and 290* oil temp (Amsoil 10W-30 Z-Rod oil) in 20 minute sessions. I was disappointed at that and am likely to have a supplemental thermostat controlled air/oil radiator which hopefully will reduce both oil and water temps.

This past Sunday at the Silver State Challenge running a steady 150 MPH, 4800 RPM in 5th with 60-70* outside temps for about 90 miles I had 220* water temp and ~260-265* oil temps, also higher than I would have expected.

FNBADAZ06

surprised about that

Josh B.

That's interesting Dave. That's hot outside by some standards, but I would think ECT wouldn't climb to 245. I installed an Improved Racing Thermostat last year. In short, it didn't work as I expected it to. It had a 100C thermostat. The oil never got hot enough for the thermostat to function, even with the heat exchanger circuit 90% blocked by the thermostat.

I removed the Improved Racing thermostat and Oil lines and installed a ZR1 oil cooler. Oil temps are in the 200 range, much better than 160.

So, I dump my oil heat into the coolant also, just via the ZR1 oil cooler. Thank you for the Dewitts data, I hope that you are able to reduce those ECTs.

MTPZ06

Josh, Congrats on kicking this build off! Impressive list of parts, and no doubt countless hours of research. Looking forward to seeing the results...after its all said and done; I hope the underwhelmer comes to be known as the overachiever.

MTPZ06

Dave, you may want to try and swap in the ZR1 heat exchanger assembly to see if that's of benefit to you before going to a supplemental t-stat controlled oil cooler. I would imagine the DeWitt's you're running is better than the OE ZR1 radiator. I upgraded my '09 to an OE GM ZR1 radiator (GM used a Griffin core) and oil cooler/heat exchanger...but if I were a hard track duty user such as yourself, I would have foregone the OE GM ZR1 rad and swapped in the DeWitt's ZR1 radiator.

2k Cobra

Must be nice!!

Best of luck with the build..

Josh B.

HA! I hope so too brother! The Underwhelmer needs a die cut sticker on the hatch with that moniker

AzDave47

PM me. I do not understand what you mean by the ZR1 heat exchanger assembly and don't want to clutter up Josh's build thread. I do want to get my oil and water track temps down. I thought the DeWitts would do that in addition to getting the oil up to temp (which it does fine).