E85 requirements for c7z
Thread Starter
Pro
Joined: Mar 2012
Posts: 652
Likes: 21
E85 requirements for c7z
While I see a lot of opinions on this matter I’m trying to get a very accurate direction for my build
so I have a c7z stock fuel system with dsx low side
Going for 800-850 tops hp
car has meth now but looking to soften this as the meth is not working well
so I have a c7z stock fuel system with dsx low side
Going for 800-850 tops hp
car has meth now but looking to soften this as the meth is not working well
Drifting
Joined: Aug 2019
Posts: 1,859
Likes: 1,264
From: Houston
Uh what are your other mods? 800-850 hp or whp?
You won't get full E85 and "800hp" without a cam unless you're spraying a stupid amount of meth. Just from my experience around my LT4 friends full E-85 requires a full fuel system upgrade (HPFP, Injectors, low side, cam), port injection, or meth. Otherwise you'll be using a blend.
You won't get full E85 and "800hp" without a cam unless you're spraying a stupid amount of meth. Just from my experience around my LT4 friends full E-85 requires a full fuel system upgrade (HPFP, Injectors, low side, cam), port injection, or meth. Otherwise you'll be using a blend.
Safety Car
Joined: Mar 2004
Posts: 4,048
Likes: 1,478
From: South Florida
You won't be able to run full E85 unless you supplement with Meth. Optionally you could add larger injectors since you have a cam(assuming you have a larger fuel lobe) and you might be able to run a high ethanol content and ditch the meth.
Supporting Vendor
Joined: Feb 2009
Posts: 4,421
Likes: 1,430
From: Mesa Az
If you're willing to blend to E50 you can make 800 with no meth with the following.
Heads/cam
Ported blower (kong x or synergy race)
our 5''
103 or 95 tb
longtubes
low side
the high side pump must be properly shimmed to get max travel as well.
If you want to do full E85 it will need meth or the LPE HPFP and xtreme di 30% injectors.
This also assumes you have the typical cooling mods to keep iat's in check. At that level our engine tank and heat exchanger is more then enough, unless you're a big racer then do our trunk tank.
Heads/cam
Ported blower (kong x or synergy race)
our 5''
103 or 95 tb
longtubes
low side
the high side pump must be properly shimmed to get max travel as well.
If you want to do full E85 it will need meth or the LPE HPFP and xtreme di 30% injectors.
This also assumes you have the typical cooling mods to keep iat's in check. At that level our engine tank and heat exchanger is more then enough, unless you're a big racer then do our trunk tank.
__________________
Cordes Performance Racing aka "CPR"
Owner of AZ's premier LSX/LTX motorsports shop
http://cordesperformanceracing.com/
www.facebook.com/cordesperformanceracing.com
joe@cordesperformanceracing.com
480-359-5914
Cordes Performance Racing aka "CPR"
Owner of AZ's premier LSX/LTX motorsports shop
http://cordesperformanceracing.com/
www.facebook.com/cordesperformanceracing.com
joe@cordesperformanceracing.com
480-359-5914
Safety Car
Joined: Nov 2011
Posts: 3,715
Likes: 343
From: Norman OK
This will also depend some (slightly) on the year of your C7Z as the 2019's have the ZR1's low side pump in the tank which helps fuel pressure. As Joe and Internet Ninja said, making big power on the LT4 isnt cheap, the upgraded HPFP and the Xtreme Di +30% injectors are very pricey. This at least a $5k upgrade alone right there.
Burning Brakes
Joined: Aug 2001
Posts: 837
Likes: 388
From: Olathe KS
Yes, the fuel system upgrades to get beyond 800 rwhp are pricey which is why a lot of folks turn to meth but meth has it's own issues since you'd be using it for fuel supply. Upgrading the HPFP and injectors will cost you almost as much as adding secondary port injection (SPI) from Crawford racing which would then allow you to run full E85 and really add power to your heart's content since you can control the secondary port injection fuel supply separately. Joe@CPR knows a ton about this stuff so I'd take his advice if I were you.
Supporting Vendor
Joined: Feb 2009
Posts: 4,421
Likes: 1,430
From: Mesa Az
Adding port is a great way to to it, but there is a tradeoff. If something fails on the holley you would never know since it runs it's own sensors and pulls nothing off the OEM computer. Is the chance high, no. But there is always a chance. So I ask every customer what is a realistic goal, if the upgraded high side parts will do it then stick with that. Because if it fails it's easier to diag and you have less chance of an engine failure from a DI injector crapping out or the HPFP not flowing as much, since these cars if they run out of their injection window yank timing hard and you feel it lay over. For this reason the M130 motec stuff is a great option since it pulls so much from the OEM PCM if a sensor fails it affects both ECU's. This is not to say the holley isn't great because it works fantastic and we do a lot of them, just things to consider as there is always tradeoff's in life.
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