Who Thinks This Is A Bad Idea?
12-05-2013, 06:08 PM
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Who Thinks This Is A Bad Idea? Some of u might remember a thread i started way back about procharging my iron 408 and swapping to E85.Ive since done a lot of research and i have also come to the conclusion that E85 isn't as common down here as i though. So heres my plan. Basically i want to not tear this entire engine apart to do this.
So i plan on redoing my fuel system and then strapping a F1A to my forged iron 408 with the hopes of 12lbs of boost. Now the way this engine sits now its got a 11.2:1 static compression ratio and the cam is a 236/242 113LSA+3. I have heard that this cam makes my dynamic compression lower than a stock LS3. If thats true than I'm sure this is fine because i know lots of people run stock bottom end LS3 with low boost and it stays together pretty well.
This is basically the run down on my current bottom end:
Clevite 77 Chamfered Main Bearings
Clevite 77 Narrow Rod Bearings
4340 Forged Eagle Crank
4340 Forged Eagle H- Beam rods with arp 2000 rod bolts
Forged Diamond Pistons Flat tops -2cc
Moly Rings
Thats pretty much my current bottom end i just can't remember if i had the Arp main rods put on it or not. I also have arp head studs and LSA heads. How strong do u guys think this bottom end is? Oh and it was built by one of our sponsors so I'm sure its assembled and machined correctly. This brings me to another question. Should i have the head chambers opened up to slightly lower compression? I know that high compression low boost builds can make a ton of power but they lose the ability to really crank up the boost before they start detonating, so whats better for a street strip the car, high compression low boost with meth injection or lower compression more boost and again meth injection?
I would like to keep the compression higher if possible but I'm just looking for opinions and options. Oh and i don't really want to change my pistons out at the moment so any attempts to lower my compression ratio would be in opening up the chambers and gasket thickness. I ask this because i have yet to see many threads about high comp low boost and how well it works.
I almost forgot to say but this will be run on 91 and meth, but i am not opposed to throwing a gallon or two of 100 octane in it to keep the octane up there although i would rather just be able to feed it just meth and 91. So lets hear techs opinion on this.
So i plan on redoing my fuel system and then strapping a F1A to my forged iron 408 with the hopes of 12lbs of boost. Now the way this engine sits now its got a 11.2:1 static compression ratio and the cam is a 236/242 113LSA+3. I have heard that this cam makes my dynamic compression lower than a stock LS3. If thats true than I'm sure this is fine because i know lots of people run stock bottom end LS3 with low boost and it stays together pretty well.
This is basically the run down on my current bottom end:
Clevite 77 Chamfered Main Bearings
Clevite 77 Narrow Rod Bearings
4340 Forged Eagle Crank
4340 Forged Eagle H- Beam rods with arp 2000 rod bolts
Forged Diamond Pistons Flat tops -2cc
Moly Rings
Thats pretty much my current bottom end i just can't remember if i had the Arp main rods put on it or not. I also have arp head studs and LSA heads. How strong do u guys think this bottom end is? Oh and it was built by one of our sponsors so I'm sure its assembled and machined correctly. This brings me to another question. Should i have the head chambers opened up to slightly lower compression? I know that high compression low boost builds can make a ton of power but they lose the ability to really crank up the boost before they start detonating, so whats better for a street strip the car, high compression low boost with meth injection or lower compression more boost and again meth injection?
I would like to keep the compression higher if possible but I'm just looking for opinions and options. Oh and i don't really want to change my pistons out at the moment so any attempts to lower my compression ratio would be in opening up the chambers and gasket thickness. I ask this because i have yet to see many threads about high comp low boost and how well it works.
I almost forgot to say but this will be run on 91 and meth, but i am not opposed to throwing a gallon or two of 100 octane in it to keep the octane up there although i would rather just be able to feed it just meth and 91. So lets hear techs opinion on this.
12-05-2013, 06:28 PM
#2
there is an article seen about compression and power and it made more power every step from 8.0 to 12 to 1 compression if you keep it out of detonation. the thing I see is you will have a very small tune window and the meth will be keeping it alive and I have never liked that as it is just one more thing that can go wrong and kill it . on my brothers sbc / d1sc we tune for no meth and use the meth for insurance in case we get to greedy with the tune. it can be done but you need a failsafe if the meth don't work it pulls like 20* timing to save it. jmho.
12-05-2013, 06:59 PM
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there is an article seen about compression and power and it made more power every step from 8.0 to 12 to 1 compression if you keep it out of detonation. the thing I see is you will have a very small tune window and the meth will be keeping it alive and I have never liked that as it is just one more thing that can go wrong and kill it . on my brothers sbc / d1sc we tune for no meth and use the meth for insurance in case we get to greedy with the tune. it can be done but you need a failsafe if the meth don't work it pulls like 20* timing to save it. jmho.