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It's good to finally see a timing table with some healthy numbers in it. I see so many people with SBF combinations barely touching 30* at cruise.
If you look at my timing table, you see where I ramp up timing (pink). I run a 2800-2900 rpm stall converter so I ramp timing right when the converter couples. Below my true stall, the converter is slipping so I don’t want a lot of timing to keep heat down. That’s another reason for going with the 4R70W transmission, I can lockup the converter when and we’re I want too, and you can bet I’ll add timing in the lower rpm and cruise.
 

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Someone who isn't smart enough to have their laptop mounted on their dashboard?

Someone who doesn't care about winning?

Haha, I kid. I love how much we all care about our image while we're secretly crossing our fingers each run. Drive a manual transmission and you know what' I'm talking about.
Actually I do drive a stick. and the car does own a NHRA Walley.
 

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'87 Cougah 428W - ⚡Cougar7.0⚡
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Discussion Starter · #63 ·

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Not the ecu. The harness is now unserviceable due to being salvaged for other wiring projects. All it would take is a new harness for the required year fox.
 

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'87 Cougah 428W - ⚡Cougar7.0⚡
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Discussion Starter · #65 ·
My ultimate goal is to achieve OEM 6th gear cruising @ 1050 RPM abilities :unsure:

1075930
 

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'87 Cougah 428W - ⚡Cougar7.0⚡
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Discussion Starter · #67 ·
Some things you just can’t do on a dyno 😎.
Most things really.

I think I've achieved the best it'll get with the cam/intake combo that I have in the Cougar:

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Cruising @ 1400 RPM in 5th gear at 45MPH is about the best I'll achieve. You can see the vacuum is nearly at the level of idle vacuum. While this is fine at WOT and higher RPMs, it sets a low limit for minimal throttle cruising in high gear. I never thought the car would drive this well after trying to use the OEM ECU which wants 14.7 AFR during closed loop. With the Holley I have it at 13.5 AFR during these conditions and it runs very smoothly. Indy will call me a moron and KJB will run a ProM ad for 5 posts after this one, but I can live with that. :)
 

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Mine also prefers to be a fatter 14.1 in certain load spots vs the 1800+ 14.7 cruise I have
 

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'87 Cougah 428W - ⚡Cougar7.0⚡
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Discussion Starter · #69 ·
Mine also prefers to be a fatter 14.1 in certain load spots vs the 1800+ 14.7 cruise I have
I think the default Holley tunes assume 10% ethanol gasoline and default to 14:1 for cruising cells. I stuck with that as I'm between 10:5 - 11:1 compression and the engine immediately ran better after converting to the Holley.

Optimizing injector timing was the next big improvement in operation and got me a savings of about 12% fuel usage at idle and several percent at lower RPM cruising as a bonus.

I think the IAC tweaks I talked about in my 1st post, then converting to the IAC vs. RPM 1D table we have been discussing has shown the most noticeable drivability improvement for a manual transmission. The 1st got excellent RPM matching while lazy cruise shifting - a massive improvement in a big engine with a lightweight flywheel. I forget to mention how the lightweight flywheel makes tuning a larger cam with short/fat intake runners even more annoying. If I had to do it again, I'd get a regular weight flywheel.

The 1D IAC vs RPM table allowed for better lower RPM cruise whereas having a constant 55% IAC cruising was a tad too much below 2k RPM. Also, the IAC is controlled more accurately when declutching so the engine drops and catches at idle speed quickly without any overshoot. You can see the lower 41% IAC cruising @ 1400 RPM and idle "catch" on declutch in the plot above. Note to users reading this, I use more IAC % than most due to feeding a larger 428 cubic inch engine.
 

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Most things really.

I think I've achieved the best it'll get with the cam/intake combo that I have in the Cougar:

View attachment 1076409

Cruising @ 1400 RPM in 5th gear at 45MPH is about the best I'll achieve. You can see the vacuum is nearly at the level of idle vacuum. While this is fine at WOT and higher RPMs, it sets a low limit for minimal throttle cruising in high gear. I never thought the car would drive this well after trying to use the OEM ECU which wants 14.7 AFR during closed loop. With the Holley I have it at 13.5 AFR during these conditions and it runs very smoothly. Indy will call me a moron and KJB will run a ProM ad for 5 posts after this one, but I can live with that. :)
Outstanding achievement! Hard data, not hand waving. There’s a lot of guys out there who will state that they car runs really good, but in actuality they run like chit whenever they are not at WOT. You just threw up the gauntlet , now let’s see who is up to the challenge, post em’ up!
 

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Carl if I load up the car and haul it up to you would you help me tune the terminator x ???
I don’t have any floor mats but I do have one 20th dash emblem lol
 

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'87 Cougah 428W - ⚡Cougar7.0⚡
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Discussion Starter · #72 ·
You just threw up the gauntlet , now let’s see who is up to the challenge, post em’ up!
Just posted to share some of the stuff I was doing that seemed to be helping with the drivetrain lash issues common with heavily cammed engines. Others have done similar and I just smugly swaggered up to the bar acting like I was smart or something. Not so, and there are different ways to skin the cat as the expression goes. Nitrous SSC was kind enough to share a video he had found that Holley made about doing the IAC differently using a 1D table - RPM vs. IAC (<- click the link to see for yourself.) Although I did the table differently than they recommend, it had the effect I wanted - catch and ramp RPMs down slowly when shifting. Here's mine:
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I didn't feel like messing with the throttle stop screw, so I left my idle settings the same. If I was starting from scratch I might have done as they recommended.

You can get a good estimation of HP by looking at fuel usage; using a BSFC of .5, then figure your fuel usage x 2 for estimate of HP. This is my VE table showing actual fuel useage, the circle is the area where HP and torque intersect aka 5250.
I finally added these to my logs. I used these formulas from Danny - they seem in the ballpark. I used 0.55 BSFC even though it's closer to .45 at WOT, high revs.
1076443
 

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Like yours having minimal IAC intervention in that lower area means you can have more control with the pedal and have it be less "touchy" especially those with bigger TB's. I'm only running a 75mm in mine but my Cobra I have a gigantic ass Mono Blade and just barely breaking the seal it lets in a TON of air. Adjusting the IAC like this works great when I'm in 1st gear putting through the kid's pick up zone at school and school zones. Then on the back side of lower than idle it helps save the engine from stalling. Also makes it nice to just slip the clutch in 1st gear without throttle to get rolling (see more kid at school stuff with a race car).

I also found having some IAC in the idle area smoothed out my idle a lot forcing it to have a minimum cycle IMHO narrows the yoyo possibility of the Holley searching to keep idle smooth. This way all it needs to do is focus on idle spark. This will also depend on how you have your throttle set screw too. If I unplug my IAC my car idles around 650. With the 25% in there between 800-1000 (my idle is set for 800) It jumps now between 25-27%, where as before it was all over the place.

As Cougar stated. No two cars are alike so your results will very and you'll want it setup to how you prefer to drive. If you're someone that likes to slowly rev up to 3k and make a sandwich between shifts, you'll want it nice and floaty. If you're someone that likes to do quick shifts at lower RPM, you won't need as much float. (aka dashpot)

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