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Running hot after Sniper EFI install

1G9T6X9

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Just had sniper efi installed on 440 stroker. Car now heats up much quicker and runs hotter. 10 mile highway drive in 80 deg temp and car is at 200+ deg. Before install it would sit at 185 and only push 200 when idling in drive through for extended period of time. Does this sound like a thermostat or water pump issue? Any ideas on where to start are much appreciated.
 
Sounds like a running lean issue, or retarded timing. Check the tune and mixtures thoroughly, make sure you have enough timing advance; it may need more than before due to the change in fueling. I guess it could be something in the actual cooling system, but that would be a heck of a coincidence..if it ran fine, a sniper system was installed, and now it gets hot, that would be the first place I'd look.
Oh, and before you do anything, verify the temps with an IR thermometer!
 
Sounds like a running lean issue, or retarded timing. Check the tune and mixtures thoroughly, make sure you have enough timing advance; it may need more than before due to the change in fueling. I guess it could be something in the actual cooling system, but that would be a heck of a coincidence..if it ran fine, a sniper system was installed, and now it gets hot, that would be the first place I'd look.
Oh, and before you do anything, verify the temps with an IR thermometer!
Thanks for the quick response. I am running an 8546 MSD distributor and per the Holley website you need to lockout the mechanic advance and disable and lock the vacuum advance as well as add an adjustable rotor. Pulled distributor and no adjustable rotor was added by mechanic. This likely would be part of a timing issue correct?
 
I believe you only do all that if you are using the sniper to control the timing. I may be wrong on that though...but if that's the case then yes it could definitely cause timing problems.

Let's call in the expert--he's a busy guy and may be a while before he sees this but he knows the sniper setups as good as if not better than anyone.
@andyf
 
I believe you only do all that if you are using the sniper to control the timing. I may be wrong on that though...but if that's the case then yes it could definitely cause timing problems.

Let's call in the expert--he's a busy guy and may be a while before he sees this but he knows the sniper setups as good as if not better than anyone.
@andyf
Or maybe @Johnny Mac could share some knowledge/experience here? :thumbsup:
 
I believe you only do all that if you are using the sniper to control the timing. I may be wrong on that though...but if that's the case then yes it could definitely cause timing problems.

Let's call in the expert--he's a busy guy and may be a while before he sees this but he knows the sniper setups as good as if not better than anyone.
@andyf

You are not wrong on that. If the EFI is controlling timing the dist needs to be locked out and let the EFI map out timing advance. The EFI does not have to control timing, in that case the dist must retain full mech and vac function.

OP, if you do not have the skills to tune the engine, meaning adjusting A/F ratio in the EFI, and adjusting timing, take it back to the person who set it up. It is not right.

Running hot now is a combination of being too lean, and too little timing.
 
Or maybe @Johnny Mac could share some knowledge/experience here? :thumbsup:
Correct on the above comments. Seems like confusion on timing control vs non.
with timing control, you do lock the distributor and phase the rotor.
with non timing control, your timing can operate as normal with a ready to run distributor.

if the rotor wasn't phased...with timing control. thats a problem. The idea there is to get the timing zero'd out, so your reluctor and rotor terminal are in sync. otherwise you could be throwing spark with 10-15 degrees of error.
 
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Correct on the above comments. Seems like confusion on timing control vs non.
with timing control, you do lock the distributor and phase the rotor.
with non timing control, your timing can operate as normal with a ready to run distributor.

if the rotor wasn't phased...with timing control. thats a problem. The idea there is to get the timing zero'd out, so your reluctor and rotor terminal are in sync. otherwise you could be throwing spark with 10-15 degrees of error.
Thanks for all the input, learning a lot from everyone. Car is going in today to hopefully figure out issue. Timing is still being run by distributor. Would timing still need to be adjusted after sniper install with this setup?
 
Thanks for all the input, learning a lot from everyone. Car is going in today to hopefully figure out issue. Timing is still being run by distributor. Would timing still need to be adjusted after sniper install with this setup?
If your timing was set before, with a ready to run distributor, and you simply swapped out the carb, for a distributor, then yes, your timing could remain the same, and you shouldn't have any issues. Timing would simply function as it did before, with the weights/springs. The sniper would run in fuel only, if you selected the Tach signal input option, and ran the yellow wire to the negative side of the coil. Holley sometimes recommends changing this setting to "cd box" and grabbing the gray output tach wire from an MSD ready to run, but i typically dont set them up like that unless trying to help a customer trouble shoot.

Now i just re-read your post, and your 8546 MSD is NOT a ready to run distributor. So something has to drive the coil. you don't mention if you have a MSD box on the car still, like a 6AL. But...in this case, the sniper can't run in fuel only, and is probably trying to control timing, through your 2 wire MSD. It can't do that w/o a box, or the coil driver. Main Question being...you said the distributor is still controlling timing? So if its not locked out...or it hasn't been phased, then those are both big issues. With the rotor out of phase, i'm sure timing is off to some margin. If the distributor hasn't been locked, i'm surprised its running at all. If you don't have a box or the coil driver mounted somewhere... I'm not sure what the mechanic did. And again, surprised its running at all.
 
If your timing was set before, with a ready to run distributor, and you simply swapped out the carb, for a distributor, then yes, your timing could remain the same, and you shouldn't have any issues. Timing would simply function as it did before, with the weights/springs. The sniper would run in fuel only, if you selected the Tach signal input option, and ran the yellow wire to the negative side of the coil. Holley sometimes recommends changing this setting to "cd box" and grabbing the gray output tach wire from an MSD ready to run, but i typically dont set them up like that unless trying to help a customer trouble shoot.

Now i just re-read your post, and your 8546 MSD is NOT a ready to run distributor. So something has to drive the coil. you don't mention if you have a MSD box on the car still, like a 6AL. But...in this case, the sniper can't run in fuel only, and is probably trying to control timing, through your 2 wire MSD. It can't do that w/o a box, or the coil driver. Main Question being...you said the distributor is still controlling timing? So if its not locked out...or it hasn't been phased, then those are both big issues. With the rotor out of phase, i'm sure timing is off to some margin. If the distributor hasn't been locked, i'm surprised its running at all. If you don't have a box or the coil driver mounted somewhere... I'm not sure what the mechanic did. And again, surprised its running at all.
Car does still have an MSD box on it so distributor has not been locked out. Also seems like it doesn’t have quite as much power as it did with the carb, would that be normal? Car is going in this afternoon so hopefully they get it figured out. Thanks again for the input.
 
Also if your initial timing is low, it’ll run hot, bump the initial to 15-20.
 
Car does still have an MSD box on it so distributor has not been locked out. Also seems like it doesn’t have quite as much power as it did with the carb, would that be normal? Car is going in this afternoon so hopefully they get it figured out. Thanks again for the input.

MSD box can be used whether or not the distributor is locked out.
 
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