C-4 Wakeup
Thread Starter
6th Gear
Joined: Jul 2018
Posts: 6
Likes: 1
C-4 Wakeup
Hi. Saw this forum and just joined. I have a 1986 coupe that I found with only 52,000 miles on it. Got it for just $5,500 from a woman whose husband just died. She just wanted to get rid of it. This is my second C-4. I did a few simple things to it to wake up the performance:
1. Replace distributor cap and rotor (original).
2. Replaced coil with MSD Blaster coil.
3. Replaced ignition module with MSD unit.
4. New 8.5mm silicone plug wires.
5. New platinum plugs gapped at .070.
MSD says you can gap the plugs up to .070 with the new coil. The factory coil is rated at 40,000 volts. The MSD coil is 50,000 volts. That's a 25% increase!
WOW those changes really added a lot of power to the L-98! It's all the power I need. This forum is pretty cool. I will be posting more.
1. Replace distributor cap and rotor (original).
2. Replaced coil with MSD Blaster coil.
3. Replaced ignition module with MSD unit.
4. New 8.5mm silicone plug wires.
5. New platinum plugs gapped at .070.
MSD says you can gap the plugs up to .070 with the new coil. The factory coil is rated at 40,000 volts. The MSD coil is 50,000 volts. That's a 25% increase!
WOW those changes really added a lot of power to the L-98! It's all the power I need. This forum is pretty cool. I will be posting more.
Race Director
Joined: Feb 2002
Posts: 11,616
Likes: 1,055
From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
2025 C4 of the Year Winner - Unmodified
2024 C4 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
Welcome sounds like a great start, enjoy
Le Mans Master
Joined: Jul 2004
Posts: 6,228
Likes: 698
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
Hi. Saw this forum and just joined. I have a 1986 coupe that I found with only 52,000 miles on it. Got it for just $5,500 from a woman whose husband just died. She just wanted to get rid of it. This is my second C-4. I did a few simple things to it to wake up the performance:
1. Replace distributor cap and rotor (original).
2. Replaced coil with MSD Blaster coil.
3. Replaced ignition module with MSD unit.
4. New 8.5mm silicone plug wires.
5. New platinum plugs gapped at .070.
MSD says you can gap the plugs up to .070 with the new coil. The factory coil is rated at 40,000 volts. The MSD coil is 50,000 volts. That's a 25% increase!
WOW those changes really added a lot of power to the L-98! It's all the power I need. This forum is pretty cool. I will be posting more.
1. Replace distributor cap and rotor (original).
2. Replaced coil with MSD Blaster coil.
3. Replaced ignition module with MSD unit.
4. New 8.5mm silicone plug wires.
5. New platinum plugs gapped at .070.
MSD says you can gap the plugs up to .070 with the new coil. The factory coil is rated at 40,000 volts. The MSD coil is 50,000 volts. That's a 25% increase!
WOW those changes really added a lot of power to the L-98! It's all the power I need. This forum is pretty cool. I will be posting more.
Team Owner
Joined: Jul 2004
Posts: 28,465
Likes: 3,288
From: Hartford WI
I don't know where doubling the spark gap really made that much noticeable difference on a street motor other than the Placebo effect. I think the money would be better spent on dumping all the fluids in the car. It flows, it goes. IF he wants to go further, find someone who can tune the car first before buying the parts and finding out that the bolt on parts actually would benefit from tuning that you can see maximum gain for the money spent.
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Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
There is zero to gain with plug gap. It is all snake oil. The MSD stuff is all made to low bidder in China since sold several years ago. The more resistance you add in the secondary side the more likely to arc all over the place in the cap and find the weakest spot in the wires.