11:1 Compression Anyone?

[Lilwhitepony]

I'm gonna be running just about 11:1 compression and I was wondering if anyone out there is running it now and what kind of octane they run. Its gonna be in a 347 stroker.... Thanks!

 

[Lyncher]

I believe you can use 94 octane and pleanty of people are running 11:1 so whats your set up

 

[Hissing Cobra]

I'm close (10:8:1) and I run fine on 93 octane. Anything less and it will ping when under a load.

 

[Lilwhitepony]

What kind of set ups do you guys have?

 

[Hissing Cobra]

What kind of set ups do you guys have?

1988 5.0 block, bored .30 over to make it a 306 and decked to create 10:8:1 compression
Internally balanced and externally balanced (fluidamper harmonic balancer)
Keith Black hyperutectic domed pistons
Elgin Pro Stock solid flat tappet camshaft 248/258 @ .50, .536/.560 lift
AFR 185's (58 cc's)
Comp Cams Roller Rockers
Edelbrock Dual Quad Intake Manifold
Two Edelbrock 500 cfm carburetors
Mac 1-3/4" longtube headers, 2-1/2" off road H-pipe, 2-1/2" catback system
MSD Billet Distributor, 6AL Ignition, Blaster II coil.

This combo produced 307 rear wheel horsepower and 278 rear wheel torque. It runs 12.70's-12.80's @ 107-110 mph.

 

[408stroker5.0]

I'm running close as well with my 408(Details in Sig)...10.8:1. I run 92 Octane Fuel and throw in some good quality octane boost as well just for a little added comfort. I'm currently running Lucas Octane Boost which seems to do just fine. I drive it on the street without any problems. Just try not to lug the engine (Work it/Put a load on it at low RPM's) otherwise Detonation can occur which will harm the engine.

Shon

 

[MatthewP]

I run an 11:1 351W on 91 octane pump gas with 30 degrees total timing and have no detonation. My home track is at 3500 ft elevation, but I also regularly race it at 2200 ft tracks with no setup changes and no detonation. I never use an octane booster in the car.

If you are at a much lower elevation, which is likely, you should be able to buy a higher octane fuel at the pumps than the 91 I can get in Calgary, and I would anticipate that your car will run fine on whatever the highest octane regular (non ethanol blended) pump gas is in your area.

As a sidebar, the Acura RSX Type S runs over 11:1 compression on pump gas without detonating.

Good luck.

-Matthew

 

[Grn92LX]

11:1, 93 pump gas, 34* total timing from 4000+..Combo in sig

 

[Lilwhitepony]

What kind of numbers do you guys run with 347 set ups?

 

[JIffy94]

Another side bar my R6 has 12.4:1 and runs on 91, even under load 6th gear and low(for the bike) rpms say 3000 i can hear no det.

 

[SQUEEZE&STROKE]

10.8:1 331. All I use is 91 pump gas...only available gas over 90 octane. No detonation, no problems, 36* total timing on the motor, 30* total timing on the Unit...Do use a 50/50 blend of 91 and 110 with the unit though...and colder plugs in both!

 

[KDK1988GT]

I'm running 11:1... on Supreme (Canadain highest Octane)

36* total adv..

Combo is...

Exhaust
- MAC 1`3/4 Long Tube Headers
- MAC Off Road H-Pipe
- Flowmaster Mufflers
- 2.5` Tail Pipes

Engine
- D.S.S 331 Stroker Kit with D.S.S Pro Lite Series Pistons
- D.S.S Main Support
- .30 Over Stock Block
- Holley SysteMAX II Intakes
- 70mm P-Plus EGR Spacer
- 70mm P-Plus Throttle Body
- 75mm Pro-Flow MAF
- MAC Cold Air Kit
- AFR 185 Heads 61cc with 2.02 Intake & 1.6 Exhaust Valves
- 1.6 Comp Rockers
- Competition Cam Xtreme Energy 224/232@ .050 Duration .555/.565 Lift
- Comp Valve Springs
- Comp Lifters
- Canton Deep Sump Oil Pan & Pick Up
- Mass Air Conversion Kit (Ford Racing)
- Kirban Aluminum Underdrive Pulleys
- Power Bond Balancer SFI 28oz

Fuel System
- 190 lph Fuel Pump
- Holley Adjustable Fuel Pressure Regulator
- 30 lbs Ford Racing Injectors

Cooling System
- Electric Fan (Mark VIII)
- 180 Degree Thermostat
- Griffen Aluminum Radiator
- Mr.Gasket Over Flow Tank
- Flexalite Adjustable Fan Thermostat

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Best times this year... NA was 11.8 @ 116.... 60 foot times of 1.6's