Hello gang. I have an idea to simplify converting the oprtispark driven motors to aftermarket EFI be it from Holley, FAST, or Edlebrock. We simply Modify the stock intake manifold to receive a distributor. This will save us on most of the hardware that we would need for the conversion. This will also largely keep the stock look under the hood. And most importantly it will be cheaper.
OK so first up here look at this: Swapping a LT1 intake into a 1st Gen Small Block Chevy (udel.edu)
I found this on the internet. But also before this I found what this person is describing. Where someone chopped the rear out of a sbc intake manifold and used it as a template over the LT part for a precise alignment of the hole. This template can be created easily.
Once the hole is drilled there should be a 1/4" raised flat put around the hole for the distributor to use. This step will require aluminum welding. And all the opens in the back of the intake for EGR should be sealed.
A small cap distributor will be used maybe like the MSD 8570 or 85701. These distributors are shorter in height than the standard 85551 distributor we all love to use for our hot rods. Same distributor but a better fit for C4. At least on paper. However, most of the EFI companies offer a specific ignition solution that is smart to go with for ease of installation.
So, if we wanted to go with Holley after modifying and re installing the intake manifold without the oil pump drive adapter removed we would buy this kit from Holley:
Holley EFI 550-936 Holley EFI Terminator X Universal MPFI Kit
And then you would get this Hyperspark kit that comes with everything you need except the ignition wires:
Holley Sniper EFI 565-300K HyperSpark Kit w/ 565-300 - Chevy
The ignition wires I think should always be cut to fit MSD wires however at this point we could just purchase a vehicle specific set of wires for any TPI C4 Corvette. So like a set of wires from Autozone for a 1988 Corvette would fit just fine.
The ECM in the optispark driven Corvettes is also interpreting the Vehicle Speed Sensor(VSS) and translating it for the instrument panel. A nice addition to C4 Corvette once the Holley controller goes in is the Pro Dash. The Pro Dash uses GPS for vehicle speed. GPS does not care about gear ratios or tire sizes and make the rest of your life easy. The Pro Dash comes in a few sizes but there is a specific mount for C4 for the smaller screen size. That Pro Dash is here:
Holley EFI 553-112 Holley EFI 6.86" Pro Dash
And the C4 Corvette mount for that Pro Dash is here:
90-96 C4 Corvette Dashboard (reversionraceworks.com)
Similar setups can be achieved with Edlebrock and also FAST but I do not know if they have a Pro Dash equivelant and if so I also do not know if they have custom mounts for C4. I think Holley is the way to go here for best results, guys.
I found this on the internet. But also before this I found what this person is describing. Where someone chopped the rear out of a sbc intake manifold and used it as a template over the LT part for a precise alignment of the hole. This template can be created easily.
Once the hole is drilled there should be a 1/4" raised flat put around the hole for the distributor to use. This step will require aluminum welding. And all the opens in the back of the intake for EGR should be sealed.
A small cap distributor will be used maybe like the MSD 8570 or 85701. These distributors are shorter in height than the standard 85551 distributor we all love to use for our hot rods. Same distributor but a better fit for C4. At least on paper. However, most of the EFI companies offer a specific ignition solution that is smart to go with for ease of installation.
So, if we wanted to go with Holley after modifying and re installing the intake manifold without the oil pump drive adapter removed we would buy this kit from Holley:
Holley EFI 550-936 Holley EFI Terminator X Universal MPFI Kit
And then you would get this Hyperspark kit that comes with everything you need except the ignition wires:
Holley Sniper EFI 565-300K HyperSpark Kit w/ 565-300 - Chevy
The ignition wires I think should always be cut to fit MSD wires however at this point we could just purchase a vehicle specific set of wires for any TPI C4 Corvette. So like a set of wires from Autozone for a 1988 Corvette would fit just fine.
The ECM in the optispark driven Corvettes is also interpreting the Vehicle Speed Sensor(VSS) and translating it for the instrument panel. A nice addition to C4 Corvette once the Holley controller goes in is the Pro Dash. The Pro Dash uses GPS for vehicle speed. GPS does not care about gear ratios or tire sizes and make the rest of your life easy. The Pro Dash comes in a few sizes but there is a specific mount for C4 for the smaller screen size. That Pro Dash is here:
Holley EFI 553-112 Holley EFI 6.86" Pro Dash
And the C4 Corvette mount for that Pro Dash is here:
90-96 C4 Corvette Dashboard (reversionraceworks.com)
Similar setups can be achieved with Edlebrock and also FAST but I do not know if they have a Pro Dash equivelant and if so I also do not know if they have custom mounts for C4. I think Holley is the way to go here for best results, guys.
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