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what kind of timing are you guys running for 15-20 psi of boost on sbf's running e85? Trying to just get a feel for where i should be at. Thanks.

Setup is an 76mm with an a2a cooler, efi, aluminum headed 347 with approximately 9:1 compression burning e85.
 

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I've got a 9:1 SBF 347 on E85. I have a CSU E85 prepped carb. I'm currently using a plug in addition to my 7al2 box, the msd timing/boost #8762. With the initial timing set at 35 on the dist., the box starts pulling timing out at 5lbs of boost. I 'm trying to get a consistant 25lbs of boost so the timing should be at 20deg when the boost reaches a minimum of 20 lbs. The box pulls up to 15 degrees of timing in increments of 1-3 degrees per second. I just started using this system so I have no real e.t slips. I did use the system on the dyno but I had the initial timing kinda low (30) so my pulls were only at 15 degrees of timing @ 28lbs of boost. It was suggested that I could turn the initial timing to about 40 degrees so the box pulls down to 25 at the 28lb boost level.. This is through a rather large a/a innercooler. On the dyno the car made over 900 rwhp... FWIW....

As previously stated, 20-22 would be a nice place to start. I also like my afr in the 10.8 - 11.0 range...
 

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26 deg with E85. 18lbs of boost with a Precision 78GTS. 347cu, 8.5 to 1, small solid roller, A2A. I gained over 150hp by going from 20 deg to 26 deg on the dyno.
 

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I've got a 9:1 SBF 347 on E85. I have a CSU E85 prepped carb. I'm currently using a plug in addition to my 7al2 box, the msd timing/boost #8762. With the initial timing set at 35 on the dist., the box starts pulling timing out at 5lbs of boost. I 'm trying to get a consistant 25lbs of boost so the timing should be at 20deg when the boost reaches a minimum of 20 lbs. The box pulls up to 15 degrees of timing in increments of 1-3 degrees per second. I just started using this system so I have no real e.t slips. I did use the system on the dyno but I had the initial timing kinda low (30) so my pulls were only at 15 degrees of timing @ 28lbs of boost. It was suggested that I could turn the initial timing to about 40 degrees so the box pulls down to 25 at the 28lb boost level.. This is through a rather large a/a innercooler. On the dyno the car made over 900 rwhp... FWIW....

As previously stated, 20-22 would be a nice place to start. I also like my afr in the 10.8 - 11.0 range...
Do you have dual needle and seat bowls on the carb?
 

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26 deg with E85. 18lbs of boost with a Precision 78GTS. 347cu, 8.5 to 1, small solid roller, A2A. I gained over 150hp by going from 20 deg to 26 deg on the dyno.

Awesome. Gives me some hope when I get my tune dialed in from a low 15* to a solid 25ish.... :cool:
 

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26 deg with E85. 18lbs of boost with a Precision 78GTS. 347cu, 8.5 to 1, small solid roller, A2A. I gained over 150hp by going from 20 deg to 26 deg on the dyno.
A buddy of mine has an extremely similar setup to this. At 20lbs and 24 deg just went 5.76 with more 60ft left and a 3"downpipe.
 
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