Tricks to tuning 80# injectors

[Mizark347]

I have been trying to get my car to run and hold an idle for 2 weeks now with 80 lb injectors and E85. My AFR bounces all over the place form 13-17:1. I tried adjusting the MAF Xer function, injector slopes and minimum PW with no luck. Are there any tricks to use when tuning these using SCT PRP?

 

[MalcolmV8]

My trick was to replace them with ID 1000s. Those 80s suck. You can get the 80s to work better though by using the minimum pulse width values from the 60 lb injector value files. I think that was the main thing SCT had me tweak. Search the SCT PRP forum, lots of discussion on this issue.

Going from memory I believe it was below 2 ms pulse widths the 80s became unpredictable and would never squirt the same amount of fuel hence the A/F jumping all over the place. However even after I had done the "hacks" from SCT which fixed it a lot I still had varying A/F. If I put the car in open loop and turned off adaptive learning so I could see exactly what the injectors were doing and cruised at 70 mph my A/F was never the same. Sometimes around 14 and other times around 15.7 almost 16 and other times anywhere in between. Put the car back in closed loop and turn adaptive learning back on and you'll see short and long term fuel trims fighting to keep AF at stoich all the time.

The other thing I hated was consistency of how the car felt in conditions I knew the car very well in such as pulling off from a traffic light. Drove me nuts how it'd never have the same AF and as a result would not feel the same in normal driving all the time. Maybe I'm just to picky but didn't like it.

I finally switched to ID 1000s and my car drives like a dream. All the AF problems were gone and no tweaking to the injector slopes etc. was needed. The ID 1000 value file is spot on.

I also realized after switching to ID 1000s just how skewed my MAF transfer curve was because it was compensating for issues with the 80s. After putting in the IDs I had to re-do my MAF transfer and I went from almost pegging my MAF meter to no where close on ID 1000s. They are pricey but you get what you pay for.

 

[TRBO VNM]

which version value file are you using?

 

[Mizark347]

I appreciate the response. I am having similar experiences and thoughts about the 80s. I tried uploading the value for min PW of the 60's and still no luck. I could probably get away with 60's. Do the 60's have similar issues as the 80's? Or should skip em and go for the ID1000's?

 

[Mizark347]

which version value file are you using?

I'm using the very latest values from Ford and SCT.

 

[MalcolmV8]

I have never personally tried the 60s but from what I read on the SCT tuning forum they work better than the 80s. I was personally done dealing with problems and got the IDs since I knew they'd work well.

I have a boosted civic I built as well. It has a tiny 1.6 liter motor with ID 1000s and it idles like stock. AF is rock solid. That's when I said to hell with the 80s and put ID 1000s in the Cobra too and couldn't be happier with them.

 

[TRBO VNM]

I'm using the very latest values from Ford and SCT.

hmm, ok. Good luck then. A car I just finished the tuner used the latest as well, made one correction based on idler rev logs and car drives perfect. Customer took it on a 500 mile road trip and was very please with drivability. I know SCT had a version 1 and 2 of the value files, but if you are using the latest, I am sure that is what this tuner used as well since it was just a few weeks ago.

 

[Mizark347]

hmm, ok. Good luck then. A car I just finished the tuner used the latest as well, made one correction based on idler rev logs and car drives perfect. Customer took it on a 500 mile road trip and was very please with drivability. I know SCT had a version 1 and 2 of the value files, but if you are using the latest, I am sure that is what this tuner used as well since it was just a few weeks ago.

That's what I heard too about the revised injector values but i did a lot of research to make sure I was using the correct values. Wish the ID1000's weren't so expensive.

 

[DSG2003Mach1]

interesting..in the reading I had done the 80lb injectors were supposed to be ok on E85, that it was just on gasoline that they ended up below the minimum pulsewidth at idle..subscribing

 

[Mizark347]

Is it possible that I have too cold of plugs for E85. I'm running AR93's which are 3 steps colder than stock?

 

[01Jes]

I also had some issues with the SD 80's. cobra had hard starts and AFR was abit unstable at idle, just rough in all. A member/svtmod by the username 04sleeper has those 80's down good. Might wanna pm/pick his brain a little. Shot in the dark but maybe he could shed some light on your issue. I purchased 60's and went with a differ tuner, never looked back . Good luck.

 

[Mizark347]

Thanks guys. I think I found a problem. I put the stock injectors back in and noticed that my load is around .30 whereas my load with the 80s was at .80. Can I just multiply my displacement and manifold volume by .6 to bring my load down at idle?

 

[MalcolmV8]

Wow why such huge changes in load due to different injectors. Did you have to tweak MAF curve between injectors?

 

[Mizark347]

Yes I did. I'm going to try and put them in one last time. I think something may have gotten confused when doing all the scaling of multiple values.

 

[MalcolmV8]

Did you have to tweak MAF curve between injectors?

Yes I did.

That right there shows a problem. The MAF curve as you know is a model of the air consumption of the motor. That is not supposed to change when you change injectors.

Having to change the air flow model characteristics of your motor to compensate for injectors would explain why your load was showing so high.

Like you said hopefully you had something else wrong too. It's definitely possible to get the car drivable on the 80s, I've done it. Just don't expect consistent A/F or as perfect and crisp throttle response as you'd get on the ID 1000s or stock injectors.

 

[Mizark347]

Well the MAF changes are due to the added VMP HPX slot meter. So I didn't expect the SCT values for this meter to be perfect anyway. I'm going to tune with the stock injectors for idle and then add the 80's to the mix and tune from there.

 

[ZOSO]

Any luck? I just fired up my new set-up and the 80's on E85 idle smooth. Im running sniper/deltaforce tuning and just a preliminary tune with the 80's and they are working good.

 

[safado]

I run 80s on E85.. no problems here

Sniper still in business... too bad they never developed the product more

 

[ZOSO]

I run 80s on E85.. no problems here

Sniper still in business... too bad they never developed the product more

I believe they are. I cant post to their help forum anymore as my email provider has been blocked. I do agree and wish they would have kept up with it and developed it more. Im just hoping I dont have the same issues with the 80's as I did with the 60's. I had a bad lean stumble with the 60's that never went away no matter what I did. I even had Chris build me a tune and it did the same thing. And Im not the only one that had that issue. If I cant get it to work I'll spend even more money and get SCT.

 

[Mizark347]

Havn't had much time to work on it yet but plan on getting it running with the 80's soon.