high static compression, boost E85???
Thread Starter
On The Tree
Joined: Nov 2013
Posts: 193
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From: Waterford, MI
high static compression, boost E85??? posted this over in the SBC section also but traffic over there is quite a bit lower, figured maybe i could get an answer over here as well.. did a thread search and found some decent info but no confirmation on if it would work or not, seems like at 8 psi or so dynamic compression would be around 12:1
okay, have a few qusetions that have been confusing me a bit here, so basically right now i have a 332 SBC (.030 327) currently have +5cc dome pistons bringing me to appox 10.4:1 compression static. now figuring in my cam specs, which was a poor desicion at the time of my XS282 cam this brings my Dynamic compression ratio way down.
http://www.compcams.com/Company/CC/c...?csid=227&sb=2
Thinking I am a bit lower than I wanted to be when running this thing N/A
Now I am going to be starting a EFI swap with LS coils and engine managment by the holley HP or Dominator ECU.. quesiton is will I be able to run low boost on this setup.. may 7-8 psi seems like with a lower dynamic compression ratio I may be able to get away with running low boost on E85. I belive my cranking cylinder pressures were around 165-175 if i remember right anyone have any insight on this, seems like It may work out pretty good because of the faster spool out of a higher compression may just have to be conservative on timing and boost.. maybe im just being optomistic because I want more power
okay, have a few qusetions that have been confusing me a bit here, so basically right now i have a 332 SBC (.030 327) currently have +5cc dome pistons bringing me to appox 10.4:1 compression static. now figuring in my cam specs, which was a poor desicion at the time of my XS282 cam this brings my Dynamic compression ratio way down.
http://www.compcams.com/Company/CC/c...?csid=227&sb=2
Thinking I am a bit lower than I wanted to be when running this thing N/A
Now I am going to be starting a EFI swap with LS coils and engine managment by the holley HP or Dominator ECU.. quesiton is will I be able to run low boost on this setup.. may 7-8 psi seems like with a lower dynamic compression ratio I may be able to get away with running low boost on E85. I belive my cranking cylinder pressures were around 165-175 if i remember right anyone have any insight on this, seems like It may work out pretty good because of the faster spool out of a higher compression may just have to be conservative on timing and boost.. maybe im just being optomistic because I want more power
Thread Starter
On The Tree
Joined: Nov 2013
Posts: 193
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From: Waterford, MI
i kind of figured this much, probably start it out with 14-16 on boost, right now it doesnt run worth crap unless idle is at, at least 26 so i just locked the hei at 36 and it loves it, so timing map should be pretty easy to set up once i get the swap going, the goal is to get the turbo set up on the SBC then eventually swap to an LS engine, and then ill only have to change the hot side and the cold side will already be set up in the car..
just kind of looking for clarification and any input if anyone runs this much compression i guess.. thanks for the advice. well see what happens i guess.. if it goes fast for a while then goes boom time for a 5.3 LOL
just kind of looking for clarification and any input if anyone runs this much compression i guess.. thanks for the advice. well see what happens i guess.. if it goes fast for a while then goes boom time for a 5.3 LOL
i kind of figured this much, probably start it out with 14-16 on boost, right now it doesnt run worth crap unless idle is at, at least 26 so i just locked the hei at 36 and it loves it, so timing map should be pretty easy to set up once i get the swap going, the goal is to get the turbo set up on the SBC then eventually swap to an LS engine, and then ill only have to change the hot side and the cold side will already be set up in the car..
just kind of looking for clarification and any input if anyone runs this much compression i guess.. thanks for the advice. well see what happens i guess.. if it goes fast for a while then goes boom time for a 5.3 LOL
just kind of looking for clarification and any input if anyone runs this much compression i guess.. thanks for the advice. well see what happens i guess.. if it goes fast for a while then goes boom time for a 5.3 LOL
We have ran multiple stock LS2s at 10.99:1 with up to 19psi on E85. You should have no trouble at all. I would run 36* at 0psi and 20* at 15 and start checking plugs. I would not be surprised if it takes 25-26* or more.
Thread Starter
On The Tree
Joined: Nov 2013
Posts: 193
Likes: 0
From: Waterford, MI
I guess I did not realize the compression was so high on a 5.3, im sure the engine I have could handle it ill probly throw some Hbeam rods in considering im already pushing ~430 hp on stock rods.. so ill get it balanced and new rods and bolts and open the gap up a little bit and run it and see what happens.. thanks for the input, i guess 8-10 psi isnt so far out of reach then.. looks like ill be ordering denmahs vsracing GT45 kit. and let er rip lol
Last edited by I-H8-RICE; Dec 27, 2013 at 08:25 AM.
