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Well, I decided to save my tune and reset the whole thing. I've had the thing on for 1.5 years now and have never been happy with the power it's put out.
I used to have peanut ports and a holley 750 DP and it would smoke the tires easily and butt dyno was somewhat happy (but still needing more). Fast forward a year and I have some higher compression heads and other goodies, and the butt dyno is disappointed. Don't get me wrong, the FI is great. It starts easily hot and cold and my plugs and oil have never looked cleaner. So I've only been fighting with trying to find that power. That led to making a ton of changes to the accell fuel, cam setting and timing. I've made so many changes I can't remember what worked and what didn't. And on top of that, I've put different heads on it. So I'm assumed the system has learned and then been throw for a loop when I upgrade and is royally confused since I've never reset anything before.

After I saved the tune, I double checked my base timing 16* and made sure my IAC steps where around 6 when warm. Then I cleared it.

-I put my fuel pump back to 40 since I have the FCC
- Loop up and down at 32/28 since i have a standard
- my decel cut at 5 to help with the popping on decel.
-AFR's around 14.2 and fast AFR's around 12.2.
-Timing: base 16, 22 @1000 and all in 36 @ 3k and 6k
These are setting i know work. I figure I'll just drive it and let it learn

This leads to my uncertainties where I need your help before I start cruising and learning:

-Cam setting I have at 3 cuz at idle Im at -6, but cruising im at 15. I feel like i don't have an aggressive cam and cant call it radical, therefore not needing a setting of 4 per Fitech (based on vaccum #'s). It's performed worse on 4 in the past. It's a lumpy thumper cam that is made to sound good at idle, not perform (comparatively speaking)?

-Vacuum ports on the Fitech, I plugged them all. I read you get an uneven distribution of fuel cuz the vacuum isn't evenly ported? So I T'd off my intake port for the vacuum booster and PCV. Is that OK?

Any other tips or tricks welcome
 

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Afternoon,

Have you hooked up manifold vacuum to both the throttle body regulator and the FCC Regulator?

I hooked both the large throttle body vacuum ports together (I have a split dual plane manifold) and ran my PCV to that new single connection. I use the Wagner dual flow PCV with a small oil/ separator.
- is there a chance you are pulling an incorrect amount of crankcase fumes through your PCV?
- could the manifold port you are using for that PCV, be providing different mixture to only some of your intake ports?
- from what I have read, you do not want your power brakes and the pcv using the same vacuum line.

Hope that helps !
Ken
 

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Could you go over how you do the save and possible restore process? I too have wondered how long it takes it to unlearn bad habits.

Do you know what your distributor was doing for timing before you made the swap? Before I made the swap I took readings of how the old one was working. When I did switch to timing control it didn't seem to change anything which I took as a good sign. After a tank of gas that way I started messing with it to see if I could get more.

Where on the intake is the vacuum port you are now using for everything? With a constant 'leak' like PCV you want it in a place that will fairly evenly distribute it. OE stuff was usually in the center of the carb with slots cut to both sides. Lots of times the ports on the intakes are in a single runner so you could really be leaning out one cylinder.

I too questioned how FiTech did it but so far I don't think its a problem. If I decided it was an issue I was going to get a spacer that either had centered ports in it or make them myself.
 

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Discussion Starter #5
Afternoon,

Have you hooked up manifold vacuum to both the throttle body regulator and the FCC Regulator?

I hooked both the large throttle body vacuum ports together (I have a split dual plane manifold) and ran my PCV to that new single connection. I use the Wagner dual flow PCV with a small oil/ separator.
- is there a chance you are pulling an incorrect amount of crankcase fumes through your PCV?
- could the manifold port you are using for that PCV, be providing different mixture to only some of your intake ports?
- from what I have read, you do not want your power brakes and the pcv using the same vacuum line.

Hope that helps !
Ken
Interesting points Ken. So do you think I should plug the one vacuum port on my rpm performer and run the pcv to the throttle body port and the booster to the other port on the fitech?

the secondaries seems to be opening all the way. Not perfectly perpendicular but for the most part

Eldo, let me see if i can find the link to resetting the fitech. it was like two steps, just have to find it again
 

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Butt dyno took a few reads to grok. Laughed at myself.
If it ran well on the 750, why go EFI? I'd look for a cheap 800/850 and rebuild... $150 total vs what $1500?
 

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Butt dyno took a few reads to grok. Laughed at myself.
If it ran well on the 750, why go EFI? I'd look for a cheap 800/850 and rebuild... $150 total vs what $1500?
Why, cause when it's 20* out I can reach in the window and turn the key and start it and it will idle on it's own without me sitting there for 5/10min till it warms up enough to do it on it's own.

It pretty much runs at the correct AFR at all points in the RPM, controls my Elect fan, and now with the 80E it gets surprisingly good mileage.
Now did my car run good with the Q850, yes but I was bored and wanted to try FI on this engine with 7/8" of vacuum.
Just for example, yesterday I lowered the car down on the lift. 1st time in 3 weeks and the battery was dead.
I put the charger on it for 1/2 hr, again, reached in the window,let it prime and my 10.5:1 406 with a 262/269 @ .050" SR cam with a HUGE single plane intake and 1" spacer FIRED RIGHT UP and idled.
To me, that's worth it.

Oh yeah, it would still spin the tires at 50 and below, just like the 850. :thumbsup:
 

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Interesting points Ken. So do you think I should plug the one vacuum port on my rpm performer and run the pcv to the throttle body port and the booster to the other port on the fitech?

the secondaries seems to be opening all the way. Not perfectly perpendicular but for the most part

Eldo, let me see if i can find the link to resetting the fitech. it was like two steps, just have to find it again
I run both fitech throttle body ports into a brass t, then straight to the PCV. I would use the manifold for the vacuum booster alone. Now I did this because my intake is a split dual plane and I wanted crankcase vapours to go to both sides of the intake.
 

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Speaking of starting over... I'd like to start over with a 2017 model year car. It would have been a heck of a lot cheaper than trying to make a car designed in the 60's run and handle like a new one.

As long as your power brakes are working the way you plumbed it, I'd just run it after the reset and see where you are at.

With regard to the carburetor feel. Currently the only way I am able to get similar feel to a carburetor is run the EFI considerably richer than what most of the vocal members here are doing. My motor runs smoother and responds better to throttle with rich settings. I do tend to tinker though, so my final tune fuel and ignition timing wise is always in progress. Performance wise I'm happy with FiTech EFI, not so much fuel economy wise at this time. I'm starting to think having both fuel economy and tire melting performance is unattainable, but I've only been playing with it for a year and not that often anymore. I didn't like the performance compromise I made to get higher fuel mileage with my motor, so I'm stuck at running a little rich.

I prefer EFI to a carburetor regardless. It's a never ending source of entertainment and as easy as it gets to try new settings.
 

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Discussion Starter #10
Speaking of starting over... I'd like to start over with a 2017 model year car. It would have been a heck of a lot cheaper than trying to make a car designed in the 60's run and handle like a new one.

As long as your power brakes are working the way you plumbed it, I'd just run it after the reset and see where you are at.

With regard to the carburetor feel. Currently the only way I am able to get similar feel to a carburetor is run the EFI considerably richer than what most of the vocal members here are doing. My motor runs smoother and responds better to throttle with rich settings. I do tend to tinker though, so my final tune fuel and ignition timing wise is always in progress. Performance wise I'm happy with FiTech EFI, not so much fuel economy wise at this time. I'm starting to think having both fuel economy and tire melting performance is unattainable, but I've only been playing with it for a year and not that often anymore. I didn't like the performance compromise I made to get higher fuel mileage with my motor, so I'm stuck at running a little rich.

I prefer EFI to a carburetor regardless. It's a never ending source of entertainment and as easy as it gets to try new settings.
I hear what you're saying, when i was running the carb, it was real rich. so rich I was replaced fowled plugs every week. Going to the FI fixed that. also fixed cold starts and smooth idle. I'm not looking for crazy performance, but I seriously think my 02 tahoe puts me back in my seat more than the chevelle. almost like i'm a cyl down, yet all my plugs look the same. this got me thinking about my vacuum source or tune.
 

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Discussion Starter #11
I run both fitech throttle body ports into a brass t, then straight to the PCV. I would use the manifold for the vacuum booster alone. Now I did this because my intake is a split dual plane and I wanted crankcase vapours to go to both sides of the intake.
Is an rpm performer classified as a single plane? I'll try your setup with the T. My brakes work fine T'd off with the PCV into the manifold. they worked fine when only plumbed into the manifold. I just don't know how that vacuum effects the fuel delivery in that part of the intake.
 

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look down into the throttle body with a good flashlight and have somebody else floor the throttle from inside the car. Observe the throttle blades, they should be vertical.
 

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look down into the throttle body with a good flashlight and have somebody else floor the throttle from inside the car. Observe the throttle blades, they should be vertical.
This is good ^^^ AND should confirm what the TPS says on the hand held. :thumbsup:

One other thing that may have not been mentioned is on the FITECH, all 4 throttle blades move simultaneously vs progressive on the carb.
That "could" be part of what your experiencing.
Just a thought.
Have you tried pump shot settings or is it just not "pulling" like with the carb?
All the exhaust gaskets upstream of the 02 are sealed up good?
 

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It's definitely not a restriction.
You had a 750dp and the fitech flows 830 cfm.
Thus confirming what I said above.
Driving around on a 2bbl then flooring it and "feeling" the secondary's kick in vs linear.
Plus the barrels are smaller on the DP.

Do these new heads have bigger intake runners?
Is the fi controlling the timing?
If so I'd go back to getting it to work without timing control the way you want then after that, let it control it.
 

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I hear what you're saying, when i was running the carb, it was real rich. so rich I was replaced fowled plugs every week. Going to the FI fixed that. also fixed cold starts and smooth idle. I'm not looking for crazy performance, but I seriously think my 02 tahoe puts me back in my seat more than the chevelle. almost like i'm a cyl down, yet all my plugs look the same. this got me thinking about my vacuum source or tune.
Our wimpy 172 HP 4 banger 2017 Jeep Renegade feels quicker than my 350+ HP V8 '65 for about a tenth of a second, but it's because the El Camino just boils the tires and doesn't have traction control. I like driving the Jeep almost as much as the hot rod. Better visibility, comfy ride, 2x the fuel mileage, and people don't intentionally pull out in front of me like they do when I'm in my old car. I'm not sure what some of the brightly colored rubber clog wearing crowd actually sees when they look at my '65 coming toward them. Butterflies and rainbows, or a rumbling gas guzzler they want off the road?

If the plugs all look white, I'd feed it some more fuel and get them at least mousey brown. There's no law against running your Idle and 1100 RPM AFRs in the 13's if that is what it takes to get some get up and go. You'll know pretty quick if richer is the wrong direction.
 

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look down into the throttle body with a good flashlight and have somebody else floor the throttle from inside the car. Observe the throttle blades, they should be vertical.
I see from your signature at the bottom you drive a 67 Chevelle. I'll assume mechanical throttle linkage? One problem I had with my 67 was when sitting in the car, floor the gas pedal, I wasn't getting full WOT. Confirmed by having a friend floor the pedal while I put my hand on the throttle arm of the FiTech. It still had another 10% to go.

I had to move the top throttle linkage bar to the top most hole at the top of the FiTech arm (the large 1/2 inch hole). You'll need an adapter bushing which is "Mr Gasket 6026" to narrow that large 1/2 hole down. I did need to shave off some of the backspacing on that bushing so that my linkage nut didn't rub against the FiTech unit. Now when I floor the pedal, my log files show TPS at 98.5 so I'm still leaving some on the table...
 

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I see from your signature at the bottom you drive a 67 Chevelle. I'll assume mechanical throttle linkage? One problem I had with my 67 was when sitting in the car, floor the gas pedal, I wasn't getting full WOT. Confirmed by having a friend floor the pedal while I put my hand on the throttle arm of the FiTech. It still had another 10% to go.

I had to move the top throttle linkage bar to the top most hole at the top of the FiTech arm (the large 1/2 inch hole). You'll need an adapter bushing which is "Mr Gasket 6026" to narrow that large 1/2 hole down. I did need to shave off some of the backspacing on that bushing so that my linkage nut didn't rub against the FiTech unit. Now when I floor the pedal, my log files show TPS at 98.5 so I'm still leaving some on the table...
I never thought of this. I just checked what my TPS reads at full throttle and I can only get 74%. I guess I need to look into getting some more travel out of that arm.

Thanks for all the recommendations guys! A little busy with a new born right now, but I'll follow up when I have some time.
 
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