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-   -   550 Primaries enough for e85? (https://www.rx7club.com/race-car-tech-103/550-primaries-enough-e85-1102787/)

FührerTüner 07-11-16 08:01 PM

550 Primaries enough for e85?
 
Shooting for 400whp on e85 with a gt35.

550 primaries 1680 secondaries.

Will the 550s get me to the staging bar?

j9fd3s 07-11-16 08:34 PM


Originally Posted by Fuhnortoner (Post 12084485)
Shooting for 400whp on e85 with a gt35.

550 primaries 1680 secondaries.

Will the 550s get me to the staging bar?

you will need roughly 30% more fuel with e85, so you will probably need to move the staging bar.

on the plus side the E85 seems to care much less about mixture, so you'll probably be able to get it to run "leaner"

FührerTüner 07-12-16 05:02 PM

30% more fuel.

So whats the Duty Cycle of the 550s with normal fuel at 2psi?

Basically i need to figure out what my duty cycle is right here:


https://cimg8.ibsrv.net/gimg/www.rx7...00acb9829e.png

ACR_RX-7 07-12-16 07:24 PM


Originally Posted by Fuhnortoner (Post 12084827)
30% more fuel.

So whats the Duty Cycle of the 550s with normal fuel at 2psi?

Basically i need to figure out what my duty cycle is right here:


https://cimg8.ibsrv.net/gimg/www.rx7...00acb9829e.png

That depends on porting and many other factors.

I'm not sure that the stock 550s can handle the ethanol without failing over time. I know they are expensive, but ID1000s would be your best bet for safety and tuning. They are far more precise than the 550s are, since they are much newer.

I get that the point of the thread is to stay with the 550s, so I went and found a nifty calculator that states that at that PW at that RPM, you are at 57-61% duty cycle.

In the first calculator, I input 7.6 at 9000 rpm. Later on in the charts, I saw around 61% at 7000 rpm in the third calculator.

Stealth 316 - Injector Duty Cycle Calculation


If you then shoot to 30% more duty cycle, that would put your injectors uncomfortably maxed out at 87-91% DC.

j9fd3s 07-12-16 10:54 PM


Originally Posted by Fuhnortoner (Post 12084827)
30% more fuel.

So whats the Duty Cycle of the 550s with normal fuel at 2psi?

Basically i need to figure out what my duty cycle is right here:


https://cimg8.ibsrv.net/gimg/www.rx7...00acb9829e.png

you can log it also. for some reason i think that stealth 316 site gives half the duty cycle, but i'd need to look into it again.

FührerTüner 07-13-16 07:23 AM

Looks like I'm buying new injectors. Thanks for the input.

dkwasherexd 09-25-16 02:50 PM

move the stage bar to 0 psi , we are running e85 with stock 550 primary and 2000 secondary on our time attack rx7

Rikk 09-25-16 03:47 PM


Originally Posted by dkwasherexd (Post 12109988)
move the stage bar to 0 psi , we are running e85 with stock 550 primary and 2000 secondary on our time attack rx7

Daniel do you know how much power you were making on this set up?

FührerTüner 09-25-16 10:11 PM


Originally Posted by dkwasherexd (Post 12109988)
move the stage bar to 0 psi , we are running e85 with stock 550 primary and 2000 secondary on our time attack rx7



Yeah decided to go meth injection instead. E85 doesn't fit my needs for this car.


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