Highest CR for low boost?
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Highest CR for low boost?
Well, I am going to begin the engine build after christmas(getting laid off so I have plenty of time to build).. Before I finalize the CR by choosing pistons I wanted to make sure I have considered all my options for power. I had been planning to build just for nitrous, but it would be nice to start saving for a turbo for this upcoming spring..
Right now with the parts I have and assuming I go with -12cc pistons i'll have a CR of 10.25.. I know of a couple turbo systems out there for escalades(which have a CR of 10:1 stock on the lq9), so I imagine 10.25 wouldent be too high, but am new to turbos. If I went with the -32cc pistons i'd end up a bit too low for what I want, right at around 8.6:1..
I was thinking of piecing together(or having one made at TRT since they are local) a small rear mount turbo but this all depends on pricing, if I can run low boost and still see decent increase, and if I keep the 10.25:1 CR.
Let me know what yall think!
-Lurius
PS: This is a daily driver, and a truck, so keep that in mind!
Right now with the parts I have and assuming I go with -12cc pistons i'll have a CR of 10.25.. I know of a couple turbo systems out there for escalades(which have a CR of 10:1 stock on the lq9), so I imagine 10.25 wouldent be too high, but am new to turbos. If I went with the -32cc pistons i'd end up a bit too low for what I want, right at around 8.6:1..
I was thinking of piecing together(or having one made at TRT since they are local) a small rear mount turbo but this all depends on pricing, if I can run low boost and still see decent increase, and if I keep the 10.25:1 CR.
Let me know what yall think!
-Lurius
PS: This is a daily driver, and a truck, so keep that in mind!
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A stock LS1 is 10:1 and plenty of people run 7-10 lbs all day long with a good tune and intercooler setup. So you should be fine. If your going through the trouble and cost of building a motor however, I'd pick one power adder or the other and build the motor for that. Just my .02
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IMO anything over 9.5 is too high. My car will only be running 10psi and my compression is around 8.3:1 and the car will be fine. Youll see a decent increase no matter what even bringing the compression down that low. You should try to get it under 9.5
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I think i'll try and keep the 10.25:1 CR and consider the turbo later on, I need to see how much power the truck will have once the new motor/tranny are in first. I like the nitrous because it can be used anytime, but all time power like a turbo/SC is very appealing as well. Any more ideas, opinions, suggestions are welcome!
-Lurius
-Lurius
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Originally Posted by Snyper
every point you go up in compression is a 5% increase in power. so its the opposite when you take it away.
Thanks,
Michael
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Well, seems liek a turbo isnt in the cards for me right now. I did find some nice -4cc pistons though, so I coulc bump it up to 11.15:1 CR, but it seems a little high for me still. I need to find some like -8cc pistons.
-Lurius
-Lurius
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Originally Posted by Slowhawk
Looks like it is going into a heavy truck.
NA/Nitrous -10.5-1
Turbo - 8.5 or 9-1 comp.
Make up your mind on what your final plan is and go from there.
NA/Nitrous -10.5-1
Turbo - 8.5 or 9-1 comp.
Make up your mind on what your final plan is and go from there.
x2...