LA360 Octane

-
Mcfarlrm

Mcfarlrm

Well-Known Member
Joined
Jan 28, 2023
Messages
185
Reaction score
46
Location
Florida
Found a local gas station that has 110 race fuel. Can I run this through an LA360?
 
I do not know what my compression is but figured this would let me know if its higher or lower than 12:1
 
If it's over 12:1 it would have let you know a long time ago.
Race fuel in a car that doesn't require it, for the most part, is a waste of money.
 
Stock 360 ? 87 octane. Boosting octane doesn't boost horsepower, only keeps it from pre-detonation if the chamber pressure is too high.
Just wasting money if it doesn't ping with lower octane fuel.
I would just make sure the station is pumping Tier 1 rated fuel.
This is fuel that is recommended by the car manufacturers. Most cut rate stations have sub standard rated fuels.
 
Just figure it out the old-fashioned way, with a compression test
Start with a fully charged battery
remove all eight plugs
the throttles should be WOT
crank until you get two successive readings of same or similar numbers
Record ALL the peak-numbers, keeping track of which hole made what pressure.
Your battery has to keep up, or it will take more and more cranking with each test.
Do not put anything into the cylinders on the first go-round.
Ideally the engine should be warm, or recently run, but summer ambient is not a deal-breaker.
Numbers around 155 to 160 are ideal. Over 160 may be an issue. Below 140 is gonna be lazy on take-off with a stock stall-speed, and lazy thru the gears with sub 3.00 gears. Tall tires will make it worse.
 
Last edited:
You may need it if you have one of these on it...
complete.setup.jpg
 
Anytime you are doing any engine diagnostics you must begin with a good, fully charged battery
(minimum 12.5 volts).
Lock the throttle blades open by just putting a large/long screwdriver down into the secondary side of the carb.
Label and remove spark plug wires, Blow off any dirt around spark plugs.
Remove and set plugs aside in proper order.
Remove coil wire completely. This eliminate possible shocks to you.
Insert proper sized compression tester plug adapter and gauge.
Hand tighten.
If you don't have an assistant, use a remote starter switch to rotate engine.
Rotate 4-6 rotations. Do the same amount for each cylinder. Record the number for each cylinder.
If more than a 10-15% difference between cylinder readings, further diagnosis required.
Normal is between 125 - 175 p.s.i. depending on engines c:r.
 
IDK if it's worth so much trouble. If it's tuned properly I'd start with a quarter tank of 87 and see if it pings under load. If it does I'd go up to 91 and try that.
 
MoparLeo said:
Anytime you are doing any engine diagnostics you must begin with a good, fully charged battery
(minimum 12.5 volts).
Lock the throttle blades open by just putting a large/long screwdriver down into the secondary side of the carb.
Label and remove spark plug wires, Blow off any dirt around spark plugs.
Remove and set plugs aside in proper order.
Remove coil wire completely. This eliminate possible shocks to you.
Insert proper sized compression tester plug adapter and gauge.
Hand tighten.
If you don't have an assistant, use a remote starter switch to rotate engine.
Rotate 4-6 rotations. Do the same amount for each cylinder. Record the number for each cylinder.
If more than a 10-15% difference between cylinder readings, further diagnosis required.
Normal is between 125 - 175 p.s.i. depending on engines c:r.
Click to expand...
I always eliminate the power to the coil. I always thought it might get over saturated.
 
Mcfarlrm said:
I do not know what my compression is but figured this would let me know if its higher or lower than 12:1
Click to expand...
Do a cranking compression test, if it is a 180 or higher you will want to run 91 octane or higher usually about 100 octane works nice for 180-200psi cranking cylinder pressure... that doesn't mean 93 wouldn't work good in the lower range of that
 
You must log in or register to reply here.
-

Back
Top