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Discussion Starter · #1 ·
I have a 355 with 11 to 1 comp. Canfield heads with an Isky 630 ground on a 110 LSA. I put a 671 and have it 10 % overdriven run it on 112 and dont seem to have any detonation problems . Wide band is green at idle and goes slightly yellow "rich" at WOT. My question is this , would the wide band hint of detonation by going red or could there still be a problem with a good reading?
 

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you're using a car air fuel meter, you need to be able to read the air fuel ratio as numbers (example : 12.5 a/f)
 

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are you positive its a wide band? you really need a wideband with numbers so you can tune it better especially since you are running high comp and FI. as for the wide band telling you if your detonating it really wouldnt.

but a cheap and easy way i found to check detonation is get a mechanics stethoscope with a long tube you will probably have to add some rubber tube to it and have someone hold it or attach the probe to your block between your deck and freeze plugs it seems to be the best place and listen to it while under load if it does detonate even slightly you will hear a jingling like a chain clanking around or glass breaking kind of a sound.
 

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I have a 355 with 11 to 1 comp. Canfield heads with an Isky 630 ground on a 110 LSA. I put a 671 and have it 10 % overdriven run it on 112 and dont seem to have any detonation problems . Wide band is green at idle and goes slightly yellow "rich" at WOT. My question is this , would the wide band hint of detonation by going red or could there still be a problem with a good reading?
if you have too much timing or boost it willl still detonate. mine does at 11.3:1 fat & detonates on 91 oct. . you are running 112 oct.,11:1& 10% over? not sure of how much boost you'r running though?
 

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if you have too much timing or boost it willl still detonate. mine does at 11.3:1 super fat & detonates on 91 oct.
11.3 isn't fat for a turbo or boost motor, its justttt right;) if you're detonating on 91 at 11.3, you need to back off the timing:)bulb or get a better intercooler.
 

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11.3 isn't fat for a turbo or boost motor, its justttt right;) if you're detonating on 91 at 11.3, you need to back off the timing:)bulb or get a better intercooler.
yeah your right, thats on my truck with a whipple & 17lbs of boost ,i lowered the boost & it still pings. timing was at 9* wot. i was thinking about my boat being fat at 9.5 afr . now thats super fat! it would have a odd sound when it couldn't burn it all
 

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Discussion Starter · #7 ·
Sorry I guess I should have said it was in a car , yes its a wide band A/F numbers and everything. I just coundnt remember exact numbers when I wrote the post . But with that being said what happens to the A/F numbers when detonation occurs?
 

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Sorry I guess I should have said it was in a car , yes its a wide band A/F numbers and everything. I just coundnt remember exact numbers when I wrote the post . But with that being said what happens to the A/F numbers when detonation occurs?
your air fuel ratio will be leannnnn, wether its from a lean fuel issue, or running to much timing. if you think detonation is occuring, plugs will always tell the truth, and i'd call the maker of your wideband set-up and ask if 112 is gonna jack with the readings, cause on alot of systems it will:)bulb

11 to 1 is alot of compression to be runnin 10 over on a 6-71. what's that, about 10-12lbs on that motor? man, i'd be running a intercooler for sure or at least 116octane or better.
 

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your air fuel ratio will be leannnnn, wether its from a lean fuel issue, or running to much timing. if you think detonation is occuring, plugs will always tell the truth, and i'd call the maker of your wideband set-up and ask if 112 is gonna jack with the readings, cause on alot of systems it will:)bulb

11 to 1 is alot of compression to be runnin 10 over on a 6-71. what's that, about 10-12lbs on that motor? man, i'd be running a intercooler for sure or at least 116octane or better.
what about E-85?
 

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That's what I've been telling him and it is available locally.
 

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Discussion Starter · #12 ·
The E-85 is something that I have thought of but I am just not familiar enough with it to go that rout . I know Slow boy has a thread about his conversion but not enough specifics for me. Maybe we need to start a E-85 conversion thread with some accurate data and numbers . But just dont expect me to start it ,I would be talking out my ass.
 

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The E-85 is something that I have thought of but I am just not familiar enough with it to go that rout . I know Slow boy has a thread about his conversion but not enough specifics for me. Maybe we need to start a E-85 conversion thread with some accurate data and numbers . But just dont expect me to start it ,I would be talking out my ass.
what's so complicated about it? you just basically prepare the fuel system as you would for methanol, make sure the fuel lines are at least 8an, run a regulator that'll handle methanol, make sure your fuel pump is up to the task, and that it's gonna make at least 140gph at a steady 5-6psi at wot at least. e85 conversion kits are a dime a dozen these days, check ebay, lotta match meter'n plates and gasket sets on there.

seriously, if you've got e85 locally and a steady supply, you're insane for not goin that route. you'll cut your fuel cost by at least a 1/3 , pick up more hp/tq too boot:)grn
 

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That's what I've been telling him and it is available locally.
he's new here, so maybe i should ask you if he is slow in the head or something?lmao, i'd give a pinkie toe for a steady supply of the stuff:D
 
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