compression ratio for new motor.
#1
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compression ratio for new motor.
i was at 9.0:1, and i was running 20psi, I was told that 9.0 was a lil on the high side, the truck is going to play on the street more than the track but i do want to hit the 1000rwhp mark and run in the mid 10s with the big tank. what do yall think about 8.5:1 and do you think i will notce the loss out of boost on the street,(even tho im in boost all the time) and it hard to spoole the 88mm so will it be that much worse than the 9.0:1 motor?
thanks Josh
thanks Josh
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i was at 9.0:1, and i was running 20psi, I was told that 9.0 was a lil on the high side, the truck is going to play on the street more than the track but i do want to hit the 1000rwhp mark and run in the mid 10s with the big tank. what do yall think about 8.5:1 and do you think i will notce the loss out of boost on the street,(even tho im in boost all the time) and it hard to spoole the 88mm so will it be that much worse than the 9.0:1 motor?
thanks Josh
thanks Josh
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Alot of guys are running that and then some on the comp end.. Just need to keep a eye on timing, use alot of meth... Even with it being 408 inches, with a 8.5 comp ratio it is going to be a dog untill you get into boost.. imo I would stay about where you are at
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Maybe this will help:
I run 8.5 on my lil truck, but it's light, power is great all around and plan on running 20psi.
The 408 we just did was low 9:1 compression, maybe the owner will chime in.
One of the 408's for a customer I built had 10.6 cr, daily driving was great! Held 12psi and made 821hp, but i would push it any higher, well maybe a couple psi.
I think 9:1 will get you there, so will anything less, cr wise.
I run 8.5 on my lil truck, but it's light, power is great all around and plan on running 20psi.
The 408 we just did was low 9:1 compression, maybe the owner will chime in.
One of the 408's for a customer I built had 10.6 cr, daily driving was great! Held 12psi and made 821hp, but i would push it any higher, well maybe a couple psi.
I think 9:1 will get you there, so will anything less, cr wise.
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sooo a lil over 8.5 will be good? ill just have to see how low he can get it, i think 8.5 or.6 is all. but will see. im just ready to get it back in the truck. my new 4l80 has about 80miles on it and 4 track passes...lol, hell have not even tuned the TCI box yet.
farmtruc:: what kind of boost contr. do yall use? i have a greddy p.s.2 and dont know how to run it. i think that took the head and block out last week. just thing. when it goes into 3rd and locks up the cov. it puts a lot of load and boost justs like 5psi or more. i know i need to play with the gane or what ever the japs call it..
farmtruc:: what kind of boost contr. do yall use? i have a greddy p.s.2 and dont know how to run it. i think that took the head and block out last week. just thing. when it goes into 3rd and locks up the cov. it puts a lot of load and boost justs like 5psi or more. i know i need to play with the gane or what ever the japs call it..
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im not sure what to use.. i mean i put in the thread what i was using at the track. i ran over 5 gals of c16, VP racing, and meth...not sure what you mean about "use good fuel this time" what do you use. i guess i could run C23 or maybe Nitro....??