Boosted 1999 questions (map sensor/flexfuel)
Thread Starter
Instructor
Joined: Oct 2022
Posts: 128
Likes: 22
From: Florida
Boosted 1999 questions (map sensor/flexfuel)
Hey guys I put a deposit down on a built/boosted 1999 c5. It is on e85 right now and I had plans to install a flex fuel sensor and also tune for 93. After doing some research here it looks like there might be alot involved to make that happen (ecu swap etc).is there an easy way to do a flex sensor or will I need to convert to a 93 tune? There isn't much e85 around me.
I also read that the 99 ecu will only read a 2 bar map sensor. Is that true as well? The engine is built and can easily handle 1000hp. So with that being said I would need a larger map sensor. Will the 1999 be an issue with that or did I read wrong? Thank you very much for any help
I also read that the 99 ecu will only read a 2 bar map sensor. Is that true as well? The engine is built and can easily handle 1000hp. So with that being said I would need a larger map sensor. Will the 1999 be an issue with that or did I read wrong? Thank you very much for any help
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
not an ez or cheap process. depending on how you go, new aftermarket ecm or the later vette 2004 ecm and load the flex fuel tables
There are some older threads that talk about wiring the flex sensor and it does work, but it's not real common and might be hard to get help
the factory ecm without failsafe and widebands make flex fuel a bit risk to me
and aftermarket ecm, install and tune, is very expensive
cheap route, have 2 tunes, pump gas, and e85 and use the fuel pump to empty tank or drain it.
flexfuel is great as you don't have to worry about the variable fuel quality and alchy content, but not cheap
boost a muv!
There are some older threads that talk about wiring the flex sensor and it does work, but it's not real common and might be hard to get help
the factory ecm without failsafe and widebands make flex fuel a bit risk to me
and aftermarket ecm, install and tune, is very expensive
cheap route, have 2 tunes, pump gas, and e85 and use the fuel pump to empty tank or drain it.
flexfuel is great as you don't have to worry about the variable fuel quality and alchy content, but not cheap
boost a muv!
Last edited by Rkreigh; Apr 2, 2023 at 05:18 AM.
Thread Starter
Instructor
Joined: Oct 2022
Posts: 128
Likes: 22
From: Florida
not an ez or cheap process. depending on how you go, new aftermarket ecm or the later vette 2004 ecm and load the flex fuel tables
There are some older threads that talk about wiring the flex sensor and it does work, but it's not real common and might be hard to get help
the factory ecm without failsafe and widebands make flex fuel a bit risk to me
and aftermarket ecm, install and tune, is very expensive
cheap route, have 2 tunes, pump gas, and e85 and use the fuel pump to empty tank or drain it.
flexfuel is great as you don't have to worry about the variable fuel quality and alchy content, but not cheap
boost a muv!
There are some older threads that talk about wiring the flex sensor and it does work, but it's not real common and might be hard to get help
the factory ecm without failsafe and widebands make flex fuel a bit risk to me
and aftermarket ecm, install and tune, is very expensive
cheap route, have 2 tunes, pump gas, and e85 and use the fuel pump to empty tank or drain it.
flexfuel is great as you don't have to worry about the variable fuel quality and alchy content, but not cheap
boost a muv!
Do you happen to know if the 1999 ecu will work with a map sensor higher than a 2 bar? It probably wont be an issue for me now, just planning for the future. Thanks again!!
Former Vendor
Joined: Aug 2011
Posts: 1,307
Likes: 115
From: Tampa Fl
St. Jude Donor '12
Corvette Tuner in Tampa
That's going to be an extremely difficult platform to reach your goals on.
Are you currently running E85 without a flex fuel sensor?
Phil
EMAIL: Tuning@TampaTuning.com
Website >>> https://shop.tampatuning.com/
CHECK OUT MY SHORTS : https://www.youtube.com/@tampatuning/shorts
Street Performance Tune Package starting from $380.00
Instagram: TampaTuning
Are you currently running E85 without a flex fuel sensor?
Phil
EMAIL: Tuning@TampaTuning.com
Website >>> https://shop.tampatuning.com/
CHECK OUT MY SHORTS : https://www.youtube.com/@tampatuning/shorts
Street Performance Tune Package starting from $380.00
Instagram: TampaTuning
Thread Starter
Instructor
Joined: Oct 2022
Posts: 128
Likes: 22
From: Florida
That's going to be an extremely difficult platform to reach your goals on.
Are you currently running E85 without a flex fuel sensor?
Phil
EMAIL: Tuning@TampaTuning.com
Website >>> https://shop.tampatuning.com/
CHECK OUT MY SHORTS : https://www.youtube.com/@tampatuning/shorts
Street Performance Tune Package starting from $380.00
Instagram: TampaTuning
Are you currently running E85 without a flex fuel sensor?
Phil
EMAIL: Tuning@TampaTuning.com
Website >>> https://shop.tampatuning.com/
CHECK OUT MY SHORTS : https://www.youtube.com/@tampatuning/shorts
Street Performance Tune Package starting from $380.00
Instagram: TampaTuning
I'm very glad you responded because you are who I would like to tune the car. I'm in Crystal River about 1.5 hours north of you. The car has a built iron block 370, vortech t trim, on e85 right now without a flex sensor. I would like to tune it on 93 with meth injection.
What is the limiting factor for the car? I honestly would be happy with 600-650ish whp. It has a built trans, clutch and stage 4 rpm diff as well. It's over 700whp now on e85. There is just no e85 near me at all. That's the reason for wanting to switch to 93/meth injection
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
I'm running a TTiX TT car with meth injection and would like to go a slightly different route (meth dependant)
holley just came out with a dual fuel rail, dual injector high rpm intake for the LS engines
I'd like to take the primary and run pump gas, and the secondary injectors use a Mega or Micro Squirt and dual wide bands
it would be a more sophisticated meth injection and have better fuel control with the wide bands
I'd also like to run dual tunes, one for pump gas, and one for meth with more boost on kill
holley just came out with a dual fuel rail, dual injector high rpm intake for the LS engines
I'd like to take the primary and run pump gas, and the secondary injectors use a Mega or Micro Squirt and dual wide bands
it would be a more sophisticated meth injection and have better fuel control with the wide bands
I'd also like to run dual tunes, one for pump gas, and one for meth with more boost on kill
Thread Starter
Instructor
Joined: Oct 2022
Posts: 128
Likes: 22
From: Florida
I'm running a TTiX TT car with meth injection and would like to go a slightly different route (meth dependant)
holley just came out with a dual fuel rail, dual injector high rpm intake for the LS engines
I'd like to take the primary and run pump gas, and the secondary injectors use a Mega or Micro Squirt and dual wide bands
it would be a more sophisticated meth injection and have better fuel control with the wide bands
I'd also like to run dual tunes, one for pump gas, and one for meth with more boost on kill
holley just came out with a dual fuel rail, dual injector high rpm intake for the LS engines
I'd like to take the primary and run pump gas, and the secondary injectors use a Mega or Micro Squirt and dual wide bands
it would be a more sophisticated meth injection and have better fuel control with the wide bands
I'd also like to run dual tunes, one for pump gas, and one for meth with more boost on kill
That sounds like a killer setup. I'm new to the corvette platform most of my back ground is with bikes. Is there a way for us to run 2 separate tunes and be able to switch back and fourth? If so how would that be accomplished? We do it all the time with the bikes. Either through the factory ecu, power commander, or stand alone. Alot of guys will have a pump gas tune and a race gas tune.
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Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
another more simple approach, install the right injectors and fuel system to support e85 and you can switch back and forth between pump gas and e85 by just loading the right tune
make sure you get most of the e85 out before you fill up on pump gas and reload the tune. I'm going to do that on my blower car. Run lower rpms and timing on pump gas (say 6200) and set on "kill" load up e85 and tune and rev out to 7200 for more boost
just make sure you tune for zero detonation. losing a few ponies isn't worth losing a few pistons. Ask me how I know.
make sure you get most of the e85 out before you fill up on pump gas and reload the tune. I'm going to do that on my blower car. Run lower rpms and timing on pump gas (say 6200) and set on "kill" load up e85 and tune and rev out to 7200 for more boost
just make sure you tune for zero detonation. losing a few ponies isn't worth losing a few pistons. Ask me how I know.
