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EZ EFI 2.0 Throttle Body System Vehicle #2 - An '81 GMC

Discussion in 'FAST Support Forum' started by A A, Jun 5, 2016.

  1. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    I've related much concerning one of my vehicles here using the EZ EFI 2.0 Throttle Body system, so I guess my experiences with a second system in another vehicle may also be helpful. Here's a link to the first system - http://www.cpgnation.com/forum/thre...with-dual-plane-intake-vs-single-plane.25871/

    Vehicle number two is a power everything 1981 GMC Sierra Classic, with a 355 Chevy small block I built and installed to the truck in 1993. The engine, as built then, made a reliable 350 horsepower on the dyno (actually about 25 more). I put a total of 36,000 miles on the engine after the install, and never changed anything but the plugs and wires, oil, antifreeze, and other normal service items. The engine has forged pistons, stage two rods, and other goodies inside.

    After 23 years, I figured it was time for a refresh with some upgrades even if the engine still did run great. A number of things had quit working like the truck's R12 air conditioning. I installed a new compressor, hoses, evaporator valve, a new evaporator filter, and a new pressure switch - all for use with R4 refrigerant and oil. That just wetted my appetite with the AC working again. So I installed new tires and rims. I started enjoying driving the old truck again with its antique tag and it's loud turbo muffler exhaust.

    Lol, the hot rodder in me surfaced again. So, I purchased Trick Flow 195 "Fast As Cast" heads, A Super Victor intake, a COMP XFI HR cam, and all the roller goodies needed to up the power. I also peeled the old rusty headers to install a new set of stainless steel "shorty" headers, and installed a new X-pipe stainless PYPES Race Pro 2 1/2" dual exhaust with straight through perforated pipe mufflers in place of the 23 year old rusty dual steel exhaust and turbo mufflers. In the process, I installed a new Hooker cross member (actually for LS engine swaps) in order to tuck the exhaust higher. The Hooker cross member worked very nicely. The installed new exhaust left me shell shocked - the old exhaust had always been very loud, and this one isn't much louder than the exhaust on my new stock Chevy Silverado - even when I rev the GMC.

    I knew the old 2500 stall converter in the turbo 350 I had built with a B&M upgrade kit didn't seem to be working correctly when under pressure, for some years - even though the transmission still shifted nice and crisp.

    With the new parts and the EZ EFI 2.0 Throttle Body installed, everything had been working great - until I decided to drive the truck recently to fill a 55 gallon drum with diesel fuel. The engine was running great, but I soon began noticing the transmission shifts weren't crisp and were getting weaker. Fluid was 1 pint low but clean, and I added some as I looked at the modulator, lines, and TV cable. I nursed the truck seven miles back toward home at all of 30 miles per hour on level ground. Attempting more speed just revved the engine. With the one hill near my home, I put the truck in reverse and drove the last two miles home in reverse - knowing the forward gears would never pull the hill. Happily, reverse was still working good and I got home without a the need of a tow. Once there, I found the forward drive couldn't move the truck with so much as my foot holding pressure on level ground. I could actually physically roll the truck backwards in drive with one foot on the ground.

    Yes, this should be expected since the engine now makes some 450 horsepower or better, but I hadn't stuck my big foot into it at all. Either a seal began leaking or the old converter lost a piece of something into the front clutch pack - should have changed that thing long back, but didn't. Anyway, I'll have a new TCI stall converter and Street Fighter Transmission to install come Tuesday. I just don't feel like rebuilding the old transmission, and I would still need additional parts to beef the transmission up to the new horsepower level. The new TCI should be good for 575 ponies - well above my 355's new horsepower level. Once in, I'll give the new transmission an easy break-in - until I do decide to stick my foot to the pedal and light the tires up. What I did find, while the old transmission still worked, was the EZ EFI 2.0 Throttle Body system worked flawlessly in my purposely easy driving.

    With the drivetrain fixed, I'll be making timing changes and etcetera to the EZ EFI 2.0 fuel injection, and leaving my notes here in this thread. With the new transmission, I'll be using the normal lead foot driving style I had been avoiding in this truck.
     
    Last edited: Jun 10, 2016
  2. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Got the new TCI Street Fighter transmission Tuesday, but it looks like other projects are going to delay that install for a while. GRRR! At least I'll soon have a new large stone patio with a roof over it - which means I'll be barbequing more out of the hot sun. Problem is, I also have a new solar panel system to install on the patio roof - once the roof is installed. Oh well, at least I still have my TA and several other old toys to play with on the street.
     
    Last edited: Jun 10, 2016
  3. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    With the cooler weather, I finally got started on the pickup again. I installed the new turbo 350 Street Fighter short shaft transmission in place of the old true long shaft turbo 350 - which meant I had to have a new longer driveshaft. I picked up the new 4" tube driveshaft Thursday and installed it Friday.

    I also installed brand new oil cooler lines with a new 2500 stall speed converter - and swapped in another 355 small block of 400 horsepower with iron heads. I had decided I wanted the nicer 450 horse aluminum head engine in a car. So, I'm in the process of converting this carbureted engine over to the FAST EZ EFI 2.0 system. I've installed some lower priced parts to this one and have some crazy things to overcome that were never an issue before. I used a satin Hurricane Plus 23 degree head intake and some inexpensive Summit fabricated valve covers - and wouldn't you know, the intake won't work with the valve covers. I'll have to remove material between the intake and the valve covers. That's a shame because I was ready to finish everything up and have the truck running today. At least the intake installed nicely. It will be interesting to see how the 2.0 EZ EFI fuel injection takes to this engine - it ran great on the other one from the install.
     
  4. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    On inspection, the old transmission had one burned clutch pack with no serious damage other than the rear bushing at the front to rear shaft. The old converter looked like it had been well overheated. With a new bushing and a little machine work, and a new clutch pack, the old transmission itself would have been fine again. But, I sent it off with a load of scrap - just to prevent myself from repairing it.

    Closer inspection of the Hurricane Plus intake proved it was fine - like most, it is made for aftermarket heads with higher oil cover lip rails, and can be ported for much larger intake runners. This cheap intake also had a surprisingly good gasket and port match to the GM heads using a Fel Pro 1205. These modified GM iron heads have the standard low oil cover lip rail. Two machining operations, in two places to each valve cover gasket rail, solved the issue. The throttle body and its cable adapter look great on this new intake. There is a slight difference in the distributor pad height on this intake and the Victor Super, but a quick adjustment of the slip collar on my MSD billet distributor took care of that. The phasing rotor was already adjusted, so the distributor was a quick install. I'm still thinking of where I want to mount the red MSD Blaster coil this time. Last time, I mounted it on the front side of the power brake booster - which looked a little strange. There is a good spot on the intake in front of the distributor and behind the throttle body, but I'll need to fabricate a nice bracket.

    I'm changing my wiring so the ECU will now sit under the hood at the front of the left fender, and no longer in the cab. The old MSD 6T is staying near the distributor on the firewall. New MSD secondary wiring will run against the motor and under the headers - keeping them mostly out of sight. I have my TBI wiring to the front of the engine routed out to the ECU by the air conditioning pump. The top of this engine is getting a much cleaner look despite the factory front accessory brackets and parts.
     
  5. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Re-installed all the air conditioning yesterday and installed a new fuel pump block off plate. Just taking my time finishing up the rest of the install.
     
  6. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Reconnected more of the FAST wiring and tied it neatly down - it looks better this time around, and the fuses have better access. I painted and re-installed two factory lift brackets on the intake. Found I may need to replace the steel feed line from my drivers side tank - it's badly rusting, probably because it runs across on a brace under the open section between the cab and bed. Re-installed the battery. Need to replace a few hose clamps and make up and install the new MSD sparkplug wires.
     
  7. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Almost finished the new MSD plug wires today - running them against the block under the headers. The new look is much cleaner. The canister style "Power Tower" MSD Blaster "3" coil wouldn't fit the intake where I was considering locating it - too tall. But, I found a spot on the firewall that works good after moving some GM OEM wires.

    Edit: I must be coming down with something - the coil does fit down in the intake, and easily.
     
    Last edited: Nov 5, 2016
  8. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    The coil required an offset intake bracket to sit low in the intake. Installed an old "Engine Builders Delight" with the old MSD 6T - used to hold RPMs down with a cold engine. The EBD was just sitting around, so I might as well use it. This engine has a high pressure, high volume, oil pump.

    I was coming down with something - arthritic vertigo. I'll have to wait to finish up - rats. Just hope it clears up by election day.
     
  9. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    I was able to vote, but the vertigo was still around and days later became so bad I almost had someone transport me to the emergency room - thinking it might be something more serious. I have Celebrex for my arthritis, but dislike taking any pills. I finally decided to take one. Thirty minutes or so later, all the vertigo disappeared and hasn't returned.

    Anyway, the coil bracket I installed was a standard MSD intake bracket for Chevy intakes. Finished up the plug wiring and made two bonehead mistakes. On first start, the engine cranked but sounded like two wires were crossed - so I used an Ohmmeter to check them. Of course, I checked every wire but 5 and 7 first - before finding I had crossed them. Still, that was an easy fix. Reset the system with the Wizard and the engine started idling great. But, when I tried to accelerate with the throttle, A/F went pig rich to 10.1 and stayed there as long as the throttle was partially open. Then, I spotted I hadn't connected a vacuum line to the changed off-the-TBI-MAP-sensor. I connected the vacuum line and reset using the Wizard again, and the engine then ran great! For now, I'm leaving the ECU vacuum off, with the default Wizard timing at 20 initial, 31@3400.

    I've also removed the added filter capacitor I had previously installed to the ECU pink =12v ignition wire with the previous motor. Apparently, as I thought, it wasn't needed like it was in my Trans Am. The handheld is performing correctly and showing no errors or codes.

    The learning appears to be staying dead on the Wizard default A/F of 13.5 idle, 14.0 cruise. The 12.5 WOT is giving it perfect acceleration. Starts are easy and fast - with a cold or hot engine. With the same AC Delco R43TS plugs it was running in the cast iron heads, I haven't spotted any detonation or ping. I also kept the default 750 idle. Found some of my old paper work, and the camshaft in this engine is 228 duration @ .050 (I built this engine in 1990, and it only has about 20,000 easy highway miles on it).

    With a 750 Holley, this engine had always idled decent when warm, and ran well. With the 750 Holley it idled at 800, but had to heat up several minutes before the idle was good. With the fuel injection, the engine feels crisper and smoother on acceleration. The idle is also smoother with no warm-up needed. The exhaust tone with this engine was always a deep rumble through dual mufflers, but now has an added big block ring when idling with the new TCI Streetfighter transmission in gear. Don't recall that big block ring in gear at idle with the previous higher horsepower engine. Just going by the sound and feel, this engine now seems stronger than it was when I built it in 1990. I really can't feel any difference is this older engine and the higher horsepower newer engine I replaced - but then, I hadn't really tested the newer engine, and haven't run this one hard yet with the FAST EZ EFI 2.0 fuel injection either. The MAP is also lower than it was with the newer engine and its larger camshaft.

    Before I upgraded the previous motor, increasing its horsepower, and adding FAST EZ EFI 2.0 fuel injection, it had also run a 750 Holley. With the Holley, it always averaged 17 mpg on the highway. There may be a possibility this will improve.

    I spotted a rear wheel brake cylinder leak that has just started, so I'll replace the rear wheel cylinders before driving this truck much. Not a big deal, and the fluid is still clean - may just flush it and install silicone fluid.
     
  10. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Whoa! The TCI turbo 350 Streetfighter with the 2500 stall converter showed its stuff today. I was rolling along about 5-10 miles per hour and suddenly hit about three quarter throttle. The truck jumped hard and the tires lit up for a good fifteen feet before I got out of it. The 2500 stall feels more like a 3000 for some reason. The truck is running an average of just below 180 F. After a few trips up and down the road, I pulled the AC Delco R43TS plugs and saw they were fully coated with dry fluffy black soot. A/F is still at the ECU Wizard setting of 13.5 idle, 14.1 cruise, and 12.5 WOT. O2 % correction is staying at zero with the engine warm. Timing is still at the Wizard set 20 initial, 31@3400. The exhaust doesn't smell rich, but the pipes are showing a little black soot inside the pipes. MAP is running 37-40 warm engine, and in the low 50's cold. This cam has 114 lobe centers (an old Crane model with .488 lift). I used Rhoads lifters on the intakes to soften the duration at idle for less whump in the exhaust - that would expose the aftermarket cam. That strangely doesn't seem to be working quite as well as it did with the Holley 750. I believe the compression of this engine is 9.0:1, but it could be higher as I do recall shaving the heads - along with
    extensive other performance changes to them.

    I stopped at a local auto parts and bought the NGK UR4 factory heat range plugs for a factory 350 Chevy (compares to R45TS). I'll be doing a proper heat range check using these before making any other changes. If the UR4 plugs are too hot, I'll jump to UR6 plugs - skipping the UR5s.
     
    Last edited: Jan 14, 2017
  11. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    No doubt about it, the NGK UR4 plugs were too hot. Will be installing UR6 plugs before any further tuning. It appears this 355 ci. iron head Chevy engine will take roughly the same heat range plug as the aluminum head 355 small block Chevy I replaced.
     
    Last edited: Nov 20, 2016
  12. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    I installed NGK UR6 plugs today. With timing still at the Wizard default with the default A/F changed to 13.8 idle, 14.3 cruise, WOT at default, the UR6 plugs ran only slightly cool. The new plugs stayed clean with no signs of pre-ignition or any fluffy dark carbon. This will allow me to add some timing for mileage improvement. The engine sounds and pulls great, but the rear tires break loose far too easily now - and my 2500 rated stall speed converter still feels like a 3000 stall (not worth changing though).

    Cold start is perfect, warm start is perfect, and I'm a happy camper - other than I may add two resonators to the 2 1/2" dual exhaust.
     
  13. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Strange. After a call to FAST today, I went out and started the truck and the transmission reacted like it had a normal 2500 stall speed converter when I placed it in gear and began to drive it. I guess it took a while for some of the components to re-seat/loosen. The transmission had been built a year earlier according to its dyno tag. The engine ran the same - sweet.

    Time to get 500 miles for the first transmission filter and oil change.
     
  14. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    After a little driving time this evening, I reset A/F to 13.7 idle, 14.2 cruise. This settled some cackle that had appeared in the exhaust at decel.
     
  15. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Noticed a few drips from the old old cast iron water pump Wednesday, and ordered a new aluminum high flow pump. I should have expected this and replaced it before installing the engine - considering how long ago I built it. The new pump will arrive Monday by UPS. Last Monday, I ordered a new handheld cable and MSD module to FAST crank trigger adapter from FAST. I was told the order would ship Tuesday and I should have it before Thanksgiving. That didn't happen, so maybe that FAST order will come Monday also. The new handheld cable should allow a custom dash mounting for the handheld.
     
  16. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    The crank trigger to MSD adapter and handheld adapter cable finally came Wednesday - the original order last week hadn't processed in the FAST system, but Chris got my needed FAST order on its way this Monday. I remembered why I didn't want to purchase the handheld cable (expensive), but I like the handheld mounted to the dash. The cable has plenty of length, with room to spare for mounting the handheld just about anywhere on the dash or windshield of my '81 GMC. I also installed NGK non-resistor heat range 8 race plugs (R5674-8) to this iron head engine - used with my MSD spiral core 8.5 mm plug wires. I still have 000 IRM counts and no 2.0 ECU problems.

    The colder race plugs allowed me to raise the timing to a 34 mechanical total with 4 more vacuum advance degrees for a total of 38 degrees. The U6 street resistor plugs would not allow me to raise the timing as hoped. The engine is running extremely sweet with the new timing and AF at 13.7 idle, 14.0 cruise. WOT is at 12.7. Cold and hot crank is excellent with no enrichment changes. A long Interstate drive will determine if the cruise AF needs any further tweaks.
     
    Last edited: Dec 2, 2016
  17. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Changed mechanical total to 32 with the 4 vacuum degrees for a 36 total, set WOT AF to 12.5. 13.8 idle AF, 14.1 cruise, -2 crank enrichment, +2 acceleration, -2 cold start.
     
    Last edited: Dec 12, 2016
  18. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    New changes to this iron head small block engine:

    28 total mechanical degrees, 4 vacuum degrees for a total of 32 degrees. WOT staying at 12.5 with 13.8 idle A/F. Cruise now 14.3.
    -2 crank enrichment, +2 acceleration, -2 cold start remain the same. Running Chevron regular, the plug coloration is good with low deposits - NGK heat range 8 looks correct at the threads, and the side electrode shows correct timing. No indications of any pre-ignition or detonation. Engine averaging 176-186 Fahrenheit. Fuel mileage improving with lowered tailpipe emissions.
     
    Last edited: Dec 24, 2016
  19. A A

    A A Well-Known Member

    Joined:
    Jun 22, 2014
    Drove the "81 GMC again today, and it was performing great. I was just driving slow as I left a red light, and accelerated to 40 gently. The PYPES stainless 2 1/2" duals with quieter PYPES race mufflers sounding nice without being loud. Then, some kid in an old green short bed Ford pickup, with no mufflers, came flying up alongside me revving his engine - showing out. I politely showed him what 400 fuel injected horsepower with a 2500 stall speed can do, as my long bed truck easily walked away from him when he floored his. I was a car length or so ahead before I hit the 60 MPH speed limit and let off the gas pedal. The kid had something of a sad look on his face - knowing he was outclassed. I spared him the knowledge he was just smoked by an old guy with a small block, and not a big block truck. :) My old GMC also doesn't look like any hot rod pickup, and the small race cam really doesn't sound off much at the 750 RPM idle (it's about as quiet as my stock new Silverado), so I'm still wondering what prompted the kid in the Ford.

    It felt good driving the old truck, and it drove well all the way back home. Once there, I noticed something I didn't like - my fuel pressure was showing 17 on the handheld. Quickly using the Advanced menu, I saw that wasn't changing. I'll have to check the filters and my regulator before my next drive. But, I figure the 35 year old gas tanks probably have had time to loosen some crud in them - since filling both full and adding fuel treatment to them last week. New filters will be installed first.

    One other thing, if people really have to try racing me, I would prefer they try keeping up with my small block 406 '85 TA. It just gets where you point it a whole lot faster, and it's setup for street racing. I mostly use my '81 GMC, with its antique tag, to just haul lumber and supplies from the local hardware to my home.
     
  20. Pfingstl

    Pfingstl Member

    Joined:
    May 30, 2016
    Location:
    Denmark
    Always fun. Appearance can be deceiving.........

    I love how new passengers react when I give the Corvette full throttle. To bad the tires available for the original 8 x 15 rims are so limited. Traction is a big problem and unsafe on wet roads.
     

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