As most of you know, I recently converted to multi-port fuel injection, then to a custom 60-2 crank trigger kit. You can read about that in this Link. I liked the idea of getting rid of my CD ignition box, coil and distributor, so I upgraded to DIS (Distributorless Ignition System). Holley's DIS kit outputs more spark energy than high-power single racing coils (for forced-induction, nitrous oxide or high compression engines). I fabricated a custom stainless steel plate to mount the DIS coil pack but it's hardly noticeable in the picture.
After a successful test run with DIS, I decided, what remained of my Mallory Hall-Effect billet EFI distributor, needed to serve more purpose than just an oil pump drive. So I converted the Hall-Effect sensor to a "cam sync" sensor (for sequential EFI operation), by removing seven of the shutter blades and fabricated a stainless steel plate to cap-off what was left of my distributor. While I was at it, I made a nice adjustable spark plug wire hold-down to support the center span of wires (due to the missing distributor cap, rotor & adapter).
My engine definitely seems to run a little smoother under sequential EFI control BUT nothing very significant. Believe or not, the most significant engine improvement I've ever made since carburetion, was Holley's TBI system. It just flat out works well. All my following upgrades (MPFI, crank trigger, DIS, sequential EFI, etc.), were minor improvements. Anyway, today I drove my Bronco on a nice long joy ride and it runs awesome! The power and driveability of my 508 BBF is just incredible. EFI simply makes this truck a pleasure to drive.
Here are two pictures of the DIS coil pack and my cam sync/oil pump drive:
UPDATE:
Danny Cabral said:
I also spent some time tuning the injector end angle timing. Long story short, I settled on -45° end angle because it used slightly less fuel at idle. I like the idea of injecting fuel a little earlier during the intake stroke. ECUs have different end angle software parameters, so here's an excerpt of how Holley does it:
Holley EFI manual said:
Fuel Injector Information - Injector End Angle
Description: This is the crankshaft angle in degrees when the injectors will finish their injection event. A value of 0° will end the injection event at BDC (Bottom Dead Center) before the compression stroke. A negative value moves the event before BDC and a positive value moves the event after BDC. There could be some improvements in cylinder to cylinder fuel distribution by tuning this parameter. If modifying, it is best to move this value in a negative direction to start.
I'm no longer using a -45° injector end angle value. The end angle has a diminishing effect as the injector duty cycle reaches 90%, however, it's nice to tune this for best idle and lower RPM ranges. I spent the last week trying to determining why the right bank of my engine, always ran about half a point leaner AFR (air/fuel ratio) than the left bank, at idle and low RPMs. I needed to determine if this was an inherent characteristic of most engines or if it was EFI tuning related (meaning it's my fault).
I tried swapping the two WBO2 sensors but the AFR read the same. I confirmed there weren't any exhaust leaks. I tried swapping the spark plugs from bank-to-bank (that's when I discovered the uniform looking spark plugs) but the AFR still read the same. All the injectors are new and the fuel pressure is rock steady. The entire ignition system (DIS) is new and my timing light doesn't indicate any misfires. Even my infrared temp gun indicated all cylinders were within 10% of each other. The BBF cylinder head architecture has identical intake & exhaust ports (on all cylinders) and all my dual-plane intake runners are relatively long, so I knew there wasn't any significant air mass differences.
After exhausting all engine related aspects, I focused my attention on the Dominator EFI tuning parameters. I verified all the Individual Cylinder fuel & timing factors were zero and that my cam sync was set correctly on #1 cylinder. I then realized the only other possibility was the injector end angle. So I first tried changing it back to 0° and to my surprise, for the first time ever, the left bank AFR was leaner than the right; completely reversed! I finally found the culprit! After experimenting with many different values, I finally nailed it down to -10° injector end angle. This equalized the left & right bank AFR.
TIP: I found that watching the left & right AFR, by staring at the data monitor was difficult to track (once I got close to the optimum value). Instead, I narrowed it down to three possibilities, then datalogged each change (named each datalog "AFR Test -xx°"), so I could "see" the definitive AFR variance. I hope this provides an unambiguous method to help someone tune their injector end angle. Unfortunately, this requires dual wideband O2 sensors or alternating one wideband O2 sensor in each exhaust bank for each software change and overlay the datalogs (labor intensive but would work).
Thanks DJOHAGIN! It's funny you mention that because today I looked at the Learn Table and to my surprise, it's indicating a -8% fuel change in the idle area. The only upgrade that could cause the engine to consume less fuel is the sequential fuel strategy. As far as MPG, I haven't done any testing yet because it's no longer my daily driven vehicle...but I'll be driving it more now.
Thanks. Nice work on your intake manifold. I'm on vacation this week, maybe afterwards. I'm using Holley's new EFI System - Dominator ECU. Which EFI system are you using and are you using computer-controlled ignition timing?
Thanks. Nice work on your intake manifold. I'm on vacation this week, maybe afterwards. I'm using Holley's new EFI System - Dominator ECU. Which EFI system are you using and are you using computer-controlled ignition timing?
Im just using a a9l ford setup from the early 90's EEC IV will more than likely not spray the motor until Im able to upgrade to a Big stuff 3 setup or something like you have.... Untill then I will spend some time on dyno tuning chips lol not the best way but will get me by untill funds allow for more tech.
Thanks for your detailed posts guys. I'm heading down that road ATM and reading up as much as possible. Problem is not many people run big$$ set ups for the street!
Sequential simply means it will fire the injector in the same ignition firing order sequence and with most aftermarket systems using a maverick spark set-up it is at the beginning of valve overlap, 360 crankshaft degrees from that cylinder required spark. WHERE the camshaft rotational value is located for injector discharge is very important to low speed mileage. NO power change happens.
The injector should not be fired for that cylinder until AFTER the exhaust valve closes similar to the strategies withing OEM electronic fuel injection.
With the hardware one can simply wire the injector "backed-up" to fire that injector on the NEXT cylinder ignition firing which will make it 90 crankshaft degrees later, after the exhaust valve has closed.
NICE work! I made the swap from my prosystems 1000 billet carb to the FAST EZ EFI 2.0 and can't express the world of difference its made. My only issue is cold start where Ive got my IAC counts (15 - 20) perfect for warm idle of 850rpms but at dead cold start I peg the IAC counts at 160 and max the IAC out which only allows a 1100rpm cold start which results in a slightly rough engine warmup vibration. This was explained with engines over 500cuin and mines a 521. Only thing I can do is bump the idle rpm to 900-950 (eat more gas at idle) which will allow slightly higher cold start RPMs. Ive tried messing with the cold start enrichment and timing to see if I could get alittle more rpms but to no avail.
Other than that very SMALL minisule hiccup the EFI is truly a blessing.
NICE work! I made the swap from my prosystems 1000 billet carb to the FAST EZ EFI 2.0 and can't express the world of difference its made. My only issue is cold start where Ive got my IAC counts (15 - 20) perfect for warm idle of 850rpms but at dead cold start I peg the IAC counts at 160 and max the IAC out which only allows a 1100rpm cold start which results in a slightly rough engine warmup vibration. This was explained with engines over 500cuin and mines a 521. Only thing I can do is bump the idle rpm to 900-950 (eat more gas at idle) which will allow slightly higher cold start RPMs. Ive tried messing with the cold start enrichment and timing to see if I could get alittle more rpms but to no avail.
Other than that very SMALL minisule hiccup the EFI is truly a blessing.
Hey Blackbird, I see from your post that your in NJ (my former home state). how are you getting your ride through state inspection? if it is strip only, then I suppose the cold start is not such big deal.
PS. I was looking at the MSD "Atomic" TBI system since I also run the MSD 6AL and MSD distributor, and the MSD system does timing control and is compatible (has spark retard) with nitrous systems. Does anyone have any experience with the MSD EFI stuff?
Maybe I should ask this in a new posting.
Hey Blackbird, I see from your post that your in NJ (my former home state). how are you getting your ride through state inspection? if it is strip only, then I suppose the cold start is not such big deal.
PS. I was looking at the MSD "Atomic" TBI system since I also run the MSD 6AL and MSD distributor, and the MSD system does timing control and is compatible (has spark retard) with nitrous systems. Does anyone have any experience with the MSD EFI stuff?
Maybe I should ask this in a new posting.
I can't actually tell u but I will say there is no way in HEIL it would pass lol. But I'm looking to switch it over to QQ plates since it's a classic and since they made all those changes to QQ cars and no longer a limited driving etc.
My understanding is that MSD does not offer full timing control so don't be fooled by there words. Only two systems that offer full timing control is HOLLEY, and FAST. If your not.going to put out more than 550hp then go with the HOLLEY system, there's a write up on here and he loves it. You have more than 550hp then u need to go with the FAST or a 8 injector system.
The Holley Terminator EFI (Link) can support up to 600 HP. Furthermore, the base fuel pressure of 43 psi, can be safely increased to 60 psi for higher HP capability (Link).
The Holley Terminator EFI (Link) can support up to 600 HP. Furthermore, the base fuel pressure of 43 psi, can be safely increased to 60 psi for higher HP capability (Link).
Agreed but your still maxing out the capability of that'll type of EFI shortly after that. In other words if your planning to make decent power look at a different system.
Also I called HOLLEY and FAST and MSD and there advertised hp ratings are not accurate in that on certain sites will inflate the HP ratings. They are all 4 injector type TBs, fast, msd, HOLLEY only designed for 550hp on average. To run higher Fuel pressures u need said higher psi fuel pumps etc.
Not saying your wrong in your thinking and it will work. When u max out an Injector above 80% duty cycle your going to wear it out fast and overheat it. By increasing pressure you allow it to squirt more fuel at a lower duty cycle but that's going around the problem which is the flow rate required at the standard fuel pressure. Extra pressure puts extra stress on the pump, regulator, lines, injectors and not to mention fuel volume decreases as pressure increases.
I'd rather run the correct sized injectors at standard pressure so it's easier on parts, or slightly larger with a lower duty cycle as long as it doesn't affect low rpm fuel flow (can't slow the pulse width enough to lean it out more at idle and low rpm).
Not saying your wrong in your thinking and it will work. When u max out an Injector above 80% duty cycle your going to wear it out fast and overheat it. By increasing pressure you allow it to squirt more fuel at a lower duty cycle but that's going around the problem which is the flow rate required at the standard fuel pressure. Extra pressure puts extra stress on the pump, regulator, lines, injectors and not to mention fuel volume decreases as pressure increases.
I'd rather run the correct sized injectors at standard pressure so it's easier on parts, or slightly larger with a lower duty cycle as long as it doesn't affect low rpm fuel flow (can't slow the pulse width enough to lean it out more at idle and low rpm).
You really should do more reading & less typing, & anyone reading this thread should skip right over that most.
Danny, what is your oppinion on the new over the counter Holley EFI? seems every time they roll a new kit out it gets better,
I am considering a bigger CI engine again & the new Holley setup is intriguing,
Have you had the chance to play with an "out of the box" kit yet? helped anyone setup/tune theirs?
If so I'll hit you up with a few specific questions I have.
You'll be able to find answers to most of your questions here: http://forums.holley.com/forumdisplay.php?13-Holley-EFI
With a big boosted engine like yours, I highly suggest Holley's Coil-Near-Plug (coil per cylinder) ignition system (Link).
I wasn't sure what system you were running, last I had seen you were running individual coil packs & I was un aware that was available from Holley,
Pretty sure you were running that setup before it was readiley available, correct? That was the reason for the "out of the box". I meant no offense.
At first, I was running the new Holley EFI system with TBI (Throttle Body Injection). I later converted to MPFI (Multi-Port Fuel Injection) LINK, and then DIS (Distributorless Ignition System).
Pretty sure you were running that setup before it was readily available, correct?
Yeah, I've never actually used the Terminator TBI system (950 CFM). I used their other 900 CFM four barrel TBI unit. I'm now MPFI with Holley's 1000 CFM throttle body. Although, as you can imagine, I've helped many people (on the Holley EFI Forum) with their Terminator EFI system; it works great!
All,
I have a 521 that was built a couple years ago and I currently have it torn apart to discover what the engine builder had actually done vs. what I asked for. Im currently looking for cam timing recommendations for this combo. It will be going in a 1970 Torino with a C-6 and 3.91 gears...
New prototype at the pri show.
Look's similar to blake's modified victor intake a few years ago!!
https://www.facebook.com/photo.php?fbid=10157432403986953&set=pcb.2232513893517392&type=3&ifg=1&__tn__=HH-R&eid=ARAUyDnqHiG8OhiRChcpf2y2R9MA3kYRRB85NEk-U8J9YkxjcVIhQEatKRzBoyKnxuCLG5krxmvGRlTD...
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