LS Swap in 78 Vette

What are those off of?
Truck injectors are shorter, but not sure what those are.
 
story I got from the seller on corvette forum was they were off a LS3 with stock GM fuel rail. Guess there is a difference in fuel rails? I don't know for sure what I have except they are EV6 connectors.
 
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I think we're at the point where I cant count all the unique combinations on your build.
 
Garys 68 said:
I think we're at the point where I cant count all the unique combinations on your build.[/QUOT
I agree, but I am getting closer. Going to get the serpentine belt on today and hopefully the exhaust and O2 sensor in place. I have 4" filter for the TB, but going to figure out a way to get more air.
Click to expand...
 
Almost there

All radiator hoses are installed, going to get the exhaust fitted up this afternoon. The injector adapters are due today and should be turning the key tonight.
 
Start up not so good. Turns over good oil pressure, fuel, no fire. Got a couple of wiring issues to sort out.
 
Hang in there Don. I think we need to double check the cam and crank harness wiring. There are differences in the Holley and GM pinouts We can drink a few beers at the Damn Car show and think on it. :mobeer:
 
No problem, time for pontification and bud light.
Update on parts added, Ended up with radiator hoses from a 2005 Silverado for bottom and part of the top. Found another unknown and cut and spliced. Got a steam fitting and hose fitting from http://www.JagsThatRun.com.
Ended up using the dorman 300-201 with a bushing for power steering pump.
Got the fuel injector extenders and new orings from http://fuelinjectorconnection.com/. They had the solution right away.
 
Trouble Shooting from Holley

If the Data Monitor doesn't display consistent RPM (after syncing), start troubleshooting the crank sensor.
If all EFI wiring is correct, I'd record a Datalog and if necessary, a System Log also:

Below is a "copy & paste" of things to check. Use what applies to you:
Does the Data Monitor display legitimate cranking RPM?
Does the Data Monitor display legitimate sensor values?
Does a Datalog indicate any RPM Errors?
Are the fuel injectors spraying fuel?
Have you performed a TPS AutoSet?
Is the fuel pressure set to proper psi?
Does the fuel pump prime for 5 seconds at key-on?
Is the ECU controlling timing?
Does the timing light indicate there's spark/ignition?
What does your ignition system consist of?
Is the correct ignition type is entered in Ignition Parameters?
Are the spark plugs fuel fouled/wet?
Are you running in sequential mode?
If so, which cam sync sensor type is it?
Is the ignition timing synchronized with the ECU?
Is the keyed 12V red/white wire powered when cranking?
Is the battery fully charged?
Is it correctly wired as shown in the wiring manual?
http://www.holley.com/data/TechServi...10555rev11.pdf (Holley EFI Wiring Manual)

Does it have to read fuel pressure to function?
No, the fuel pressure transducer is optional.
 
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Fuel Pressure

Can I adapt a fuel pressure sensor to the end of the fuel rail is using the schrader valve.
 
Yes but you have to use a shrader valve adapter so the little pin is depressed, otherwise no reading.
 
Going to pick up a new crank sensor and cam sensor tomorrow. They were on the original motor so back at the troubleshooting tomorrow afternoon.
 
It's Alive.

Nothing wrong with crank or cam sensor. Had the wiring to each reversed. Started up tonight. Ran for a few minutes and worked on an exhaust leak. Will move forward tomorrow.
 
The two sensors use the same plug but the hot wire and signal wire are in different pins. Google the sensors and got the pin out sheet. I think Bullshark and I checked them about 15 times to make sure I had them wired correctly.
Maybe a lap around the hanger tonight.
 
Got the crank and cam sensors straightened out. GM uses the same weatherproof plug but the pin wiring is swapped. It would start and barely run and lots of stumbles. Have a big exhaust leak as I messed up on the exhaust manifold gaskets. Need to get gaskets specifically for the C5 exhaust manifolds I am using.
 
If you're talking about the head/manifold, I reused my LQ9 gaskets.
If you're referring to the collector/downpipe, yeah you need the C5 donut gaskets.
 
Gaskets

Turns out my exhaust manifolds cam off a C5 but from years 2001-2004. Got the correct gasket from Chevrolet and no exhaust leaks.
Got the car to run for several minutes last night. Still got a miss but the Holley was in learning mode and running smoother at the end of night. Still need to get the fans turn on sorted out and the radiator cap fixed. Thanks Bullshark and Tim
 

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