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  Topic Review (Newest First)
09-20-2019 05:35 PM
68WASAGOODYEAR I did install the progressive link on mine. It's more or less required with a manual transmission, otherwise the drivability suffers. You also have to change a setting in the handheld to enable this and also remap the acceleration enrichment vs. TPS in the Sniper software to get the full effect of this. I'm reinstalling the sniper now...

I'm still using a throttle rod, just updated with heim joints on either end.
09-20-2019 09:54 AM
lovebohn I have the other TB, but did install that linkage adapter on mine since it was super touchy at idle and with all the power it make start interesting. The new adapter did really help but it has the linkage rod hit the firewall now at the very end of the throttle travel. I"m taking a 1/4" max of WOT which isn't a big deal.

I might try a wire throttle compared to the linkage, anyone update theirs to a cable before?
09-20-2019 09:46 AM
FearlessAZ I finally got around to having my sniper unit installed on my 70. Been good so far. Only problem I have is that stiff toe in off idle. Not so bad at cruising speed. I did read through quite a few posts on the Holley forum that discuss this same problem as well as talking to a coworker who has this setup on his late 60s Mustang and early 80s cutlass.

Some of the posts talked about the linkage on the sniper being smaller than a typical carb. Holley has a bracket extender that is supposed to make that throttle more linear instead super stiff off idle. The coworker also mentioned that he put a different return spring so it isn't as stiff.

EDIT: Here is the link to the throttle lever extension
https://www.holley.com/products/fuel...BoCYvUQAvD_BwE


I only have about 50 miles on this new setup but haven't noticed anything out of the ordinary yet.
09-17-2019 07:48 PM
68WASAGOODYEAR I have posted it on the Sniper forum (same user name) and gotten some feedback, but nothing I hadn't already checked. I did hear back from Holley and they said they had been able to "recover" the ECU and that the unit had passed all their tests. They're shipping it back to me. So I'm back to square one in terms of troubleshooting the issue and preventing a recurrence.
09-17-2019 04:09 PM
lovebohn Have you posted the problem on the Holley forum? I had a few bugs on the first setup, but a quick forum post and working with the person I bought it from solved the problem now. Sure I could and will tweak it some more when I can do a dyno tune, but I have zero regrets on spending the time and money on the EFI setup. I might even go the dual quad Sniper install this winter on a SBC update.
09-13-2019 08:02 PM
68WASAGOODYEAR The rear axle is set up and good to go, which was the last big step. I have had nothing but problems with the EFI and have sent it back to Holley again for repair. At this point, I do not recommend it. It is definitely not a reliability upgrade over a carburetor. I've only driven the car outside my neighborhood a half dozen times, and it's left me stranded twice already, once requiring a tow home. I want to believe, but my confidence in the system is seriously rattled and I'm not sure I'll ever be able to drive the car without fearing its getting ready to shut down due to some electronic gizmo in the EFI randomly deciding it wants to ruin my day.

I'm giving it one more chance and then I'll be scrapping the damn thing and going with a carburetor. If it was self - tuning like they say, there wouldn't be a Holley forum full of guys who can't figure out how to get their cars running right.

Attached are some pics - it's done at this point with the exception of the fuel delivery. Lessons learned:

1) EFI sucks. Nothing but a headache.
2) I had nothing but problems with the PTFE thread sealer as well. It leaked everywhere I used it. Coolant and oil. Replaced it with Teflon tape and haven't had any problems.
3) Retorque all fasteners after the first few times you drive the car.
09-13-2019 10:54 AM
lovebohn How has everything turned out? Did you get your rough idle fixed? I have a similar setup with a 502 and terminator EFI.
08-22-2019 02:01 PM
68WASAGOODYEAR
Quote:
Originally Posted by justjohn View Post
I think the only difference between our power plants is fans. I have a Griffin radiator with their dual electric fans. With AC on, mine creeps up to 200 sitting in traffic.
I'm going to add an electric 3000 cfm Flex-a-Lite auxiliary pusher fan on the front of the radiator and use the ECU to activate it above 200 degrees. This should do the trick. I don't want to convert over entirely to efans as the mechanical fan does just fine at speed.
08-22-2019 12:04 PM
justjohn I think the only difference between our power plants is fans. I have a Griffin radiator with their dual electric fans. With AC on, mine creeps up to 200 sitting in traffic.
08-21-2019 04:04 PM
68WASAGOODYEAR Drove the car today and unfortunately ended up sitting in traffic, which I try to avoid at all costs.
The temp guage started to creep up and got to 225 before I was able to get moving. Once moving at a steady speed, it came down to 180 or so.

Do I need efans? Everything is brand new - water pump, the biggest, baddest cooling pack made by U.S. Radiator, mechanical fan, fresh coolant, etc. I'm not sure what else I could have done to avoid an overheating issue....

Thanks for any replies.
08-17-2019 07:48 PM
68WASAGOODYEAR Any idea why my starter would make a grinding sound when starting the car? Only does this intermittently. Same sound as when you try to start it when it's already running. Whenever it does this, I key off and start over and it is fine...Thanks for any replies.

She's in the shop now getting new tires, exhaust, and a re-gear. Pics to follow and lessons learned. What a long, strange trip is been...
08-12-2019 03:38 PM
68WASAGOODYEAR
Quote:
Originally Posted by justjohn View Post
Quote:
Originally Posted by 68WASAGOODYEAR View Post
Drove it today around my neighborhood. Still have a few kinks to work out. Here they are:

1) Idle quality is terrible. Sounds like a Harley and the entire car shakes. Going to have to call Holley tech support on Monday.

2) Throttle is very stiff and unforgiving. I put increasing pressure on the peddle to no effect and then suddenly - BAM. Tire chirps. Will mention this to Holley.

3) Something sounds like it is repeatedly smacking the underside of the car on the driver side with a hammer. It's especially bad in a left turn. No idea. Will have to take the wheel off and have a look.

4) Oil pressure is staying around 60 psi. Very little movement of the needle. Again, no idea. The fuel pressure guage also says 0 psi, which can't be right for obvious reasons. Electrical Gremlins. Fun.

Nothing disastrous. No leaks either, which I'm very happy about. Any thoughts on the above are appreciated. Pics to come.
This is a self-tuning system? Holley is probably going to tell you to drive it some more on the first call.
The rough idle is due in part to my O2 sensor placement: too close to the engine and needs to be further downstream. Will fix this at the exhaust shop. The stiff pedal is discussed here

https://forums.holley.com/showthread...I-WAAAY-Better

and there is a fix. I have ordered the linkage and will report back if it works. Apparently it's more or less required for manual transmissions.

The thumping sounds are an interference between the driveshaft and body. Crawling under there tonight...
08-12-2019 08:55 AM
justjohn
Quote:
Originally Posted by 68WASAGOODYEAR View Post
Drove it today around my neighborhood. Still have a few kinks to work out. Here they are:

1) Idle quality is terrible. Sounds like a Harley and the entire car shakes. Going to have to call Holley tech support on Monday.

2) Throttle is very stiff and unforgiving. I put increasing pressure on the peddle to no effect and then suddenly - BAM. Tire chirps. Will mention this to Holley.

3) Something sounds like it is repeatedly smacking the underside of the car on the driver side with a hammer. It's especially bad in a left turn. No idea. Will have to take the wheel off and have a look.

4) Oil pressure is staying around 60 psi. Very little movement of the needle. Again, no idea. The fuel pressure guage also says 0 psi, which can't be right for obvious reasons. Electrical Gremlins. Fun.

Nothing disastrous. No leaks either, which I'm very happy about. Any thoughts on the above are appreciated. Pics to come.
This is a self-tuning system? Holley is probably going to tell you to drive it some more on the first call.
08-10-2019 04:46 PM
68WASAGOODYEAR Drove it today around my neighborhood. Still have a few kinks to work out. Here they are:

1) Idle quality is terrible. Sounds like a Harley and the entire car shakes. Going to have to call Holley tech support on Monday.

2) Throttle is very stiff and unforgiving. I put increasing pressure on the peddle to no effect and then suddenly - BAM. Tire chirps. Will mention this to Holley.

3) Something sounds like it is repeatedly smacking the underside of the car on the driver side with a hammer. It's especially bad in a left turn. No idea. Will have to take the wheel off and have a look.

4) Oil pressure is staying around 60 psi. Very little movement of the needle. Again, no idea. The fuel pressure guage also says 0 psi, which can't be right for obvious reasons. Electrical Gremlins. Fun.

Nothing disastrous. No leaks either, which I'm very happy about. Any thoughts on the above are appreciated. Pics to come.
08-06-2019 01:30 PM
justjohn
Quote:
Originally Posted by 68WASAGOODYEAR View Post
Wired it up as shown in the video and had no problems. She's running now. Hopefully will have video soon.
Looking forward to seeing your impressions. This is a winter project for me.
08-06-2019 10:18 AM
68WASAGOODYEAR Wired it up as shown in the video and had no problems. She's running now. Hopefully will have video soon.
07-31-2019 02:02 PM
68WASAGOODYEAR Good grief. Watch 30 seconds of this video starting at 7:55. The Holley guy doing the install sees the SAME EXACT voltage drop I'm seeing during cranking and doesn't bat an eye. The car fires right up. 12V needed during cranking my ***. All this running around and overthinking the issue. Oh well. Hopefully this helps someone avoid all the nonsense.

https://youtu.be/1mIhs4xahBY
07-30-2019 11:52 AM
Big Dave Like I said earlier the original starter (direct drive permanent magnet starter) with the added windings found in a high torque starter will drop a 12 Volts battery down to 8 Volts. You are ahead of the game with a mini-gear drive starter that doesn't draw as much current.

Big Dave
07-30-2019 10:23 AM
68WASAGOODYEAR
Quote:
Originally Posted by justjohn View Post
Quote:
Originally Posted by Big Dave View Post
You can get 12 Volts while cranking you just need a bigger battery:

https://www.foreverpureplace.com/24-...24-85-25-b.htm

But in all seriousness there is a special 16 Volt battery that racers use to run EFI on a race car. Battery has dual circuitry so that it never gets below 12 volts. Does require a charger that plugs into 110V AC household circuit to keep it charged.

https://lifelinebatteries.com/produc...s/ll-161240tb/

Big Dave
Seems simple enough...

I still can't believe Holley requires a minimum 12v during cranking. One of our engineers provides tech service to them, I see if he can get a definitive answer.
I spoke with holley tech support on the phone yesterday evening about the voltage drop and the voltage requirements of the EFI. They said there will obviously be some voltage drop during cranking, but that the amount I'm seeing (approx. 12.5V down to around 10.5V during cranking) seems excessive and that I should be fine with 11.0V+ for the EFI during cranking.

They suggested checking all my grounds, so I'll start there I guess. I have been hyper-vigilant about grounds and I'm pretty confident in them; all new grounds and even the old ones I've run across were taken down to bare metal, a ring terminal with splice melt attached to the ground wire, bolted to the bare metal, and covered in liquid electrical tape to seal /insulate the ground. All new ground straps were added during the engine swap as well. These were missing before.

I don't think it's the starter either; it's a new Summit high-torque mini starter which shouldn't cause that big of a drop.

Thanks for all the replies. This is the last thing before I can fire it up so it is super - frustrating.
07-30-2019 08:09 AM
justjohn
Quote:
Originally Posted by Big Dave View Post
You can get 12 Volts while cranking you just need a bigger battery:

https://www.foreverpureplace.com/24-...24-85-25-b.htm

But in all seriousness there is a special 16 Volt battery that racers use to run EFI on a race car. Battery has dual circuitry so that it never gets below 12 volts. Does require a charger that plugs into 110V AC household circuit to keep it charged.

https://lifelinebatteries.com/produc...s/ll-161240tb/

Big Dave
Seems simple enough...

I still can't believe Holley requires a minimum 12v during cranking. One of our engineers provides tech service to them, I see if he can get a definitive answer.
07-29-2019 11:55 AM
Big Dave
Quote:
Originally Posted by justjohn View Post
I think getting a dedicated circuit should be no issue but you'll never get a solid 12v during crank. The system just isn't designed that way.
You can get 12 Volts while cranking you just need a bigger battery:

https://www.foreverpureplace.com/24-...24-85-25-b.htm

But in all seriousness there is a special 16 Volt battery that racers use to run EFI on a race car. Battery has dual circuitry so that it never gets below 12 volts. Does require a charger that plugs into 110V AC household circuit to keep it charged.

https://lifelinebatteries.com/produc...s/ll-161240tb/

Big Dave
07-29-2019 10:53 AM
justjohn
Quote:
Originally Posted by 68WASAGOODYEAR View Post
I do, but I need two seperate, clean 12V sources at the run position and during cranking for the EFI and holley dual sync distributor, so the factory diagram isn't much help. I have one on the back of the ignition switch, but the problem is the voltage drop. I think I need a relay or two to get around this issue. Will talk to an electrical engineer tomorrow at work to confirm.
Probably you do need relays...
What I can tell you about vehicle system voltage during cranking...(We make fuel injectors here in Greenville). For OE injectors, we manufacture to a SMOV of 6.5 volts. Static Minimum Opening Voltage is the lowest voltage at which a fuel injector will open and function. We design this way because it is not uncommon for system voltage on cranking to drop to as little as 8 volts. We see this though about the mid 2000's. With later ECUs, some cars don't even bother to send a signal to the starter below 8 volts. I think getting a dedicated circuit should be no issue but you'll never get a solid 12v during crank. The system just isn't designed that way.
07-28-2019 10:03 PM
Big Dave One wire means you get no charging from the alternator until it "lights off" at about 2200 RPM. You are relying on the magnetism of the iron core (not permanently magnetized but it retains some residual magnetic flux from running). If you want instant on you need to connect the field windings (there are pig tails that connect your blue and white wire to a CS alternator).

Otherwise you are back to cranking off the battery and hoping you have enough charge to keep your voltage up.

Big Dave
07-28-2019 08:09 PM
68WASAGOODYEAR
Quote:
Originally Posted by Big Dave View Post
Your car ran off of the battery and used the alternator to charge the battery back up after use. This leads to large swings in the voltage. Because of this Chevy introduced the CS style alternator (what the aftermarket calls a one wire) to run the cars computers.

Transistors are very, very susceptible to variations in voltage. It doesn't take much to go from static and misfires to dead parts with your current battery and SI alternator. You could fill the trunk of your car with the battery out of an electric fork lift truck and that would maintain stable voltage while the alter maintained charge. But you would be dragging the frame due to the added lead weight.

Or swap out your SI alternator for a big (105 Amp or bigger) to run your computer and the rest of the car. The CS outputs it's rate Amperage and maintains it at 12 volts from 2,400 RPM and up. Your SI isn't hitting rated power output until 4,600 RPM where the voltage is close to 14.6 volts.

It is just another reason I have never embraced EFI in a classic car.

Big Dave
Dave, I switched to a CS alternator early on when I first bought the car. Would the alternator have anything to do with this when cranking? I tried running a 2 GA wire between the alternator and battery just for the hell of it and it didn't make a difference in terms of the voltage drop.
07-28-2019 07:46 PM
Big Dave Your car ran off of the battery and used the alternator to charge the battery back up after use. This leads to large swings in the voltage. Because of this Chevy introduced the CS style alternator (what the aftermarket calls a one wire) to run the cars computers.

Transistors are very, very susceptible to variations in voltage. It doesn't take much to go from static and misfires to dead parts with your current battery and SI alternator. You could fill the trunk of your car with the battery out of an electric fork lift truck and that would maintain stable voltage while the alter maintained charge. But you would be dragging the frame due to the added lead weight.

Or swap out your SI alternator for a big (105 Amp or bigger) to run your computer and the rest of the car. The CS outputs it's rate Amperage and maintains it at 12 volts from 2,400 RPM and up. Your SI isn't hitting rated power output until 4,600 RPM where the voltage is close to 14.6 volts.

It is just another reason I have never embraced EFI in a classic car.

Big Dave
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