9:1 Compression On Street Gas, How much boost? with built internals, AEM EMS?
12-18-2003, 01:55 AM
#11
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Originally posted by Mee
lowering the compression varies. if u lower it with pistons and rods(JE forged) and a copper head gasket, than that motor should be able to run at least 19 psi on 93 octane, if u were to lower the compression other wise, for example a cheap way is to stack head gaskets, the stock bottom end will only handle between 12-15 psi, it all depends on how u tune it, and drive it. with turbo car comes the endless dyno hours of tuning, be prepared for that. as far as the drivetrain goes, get urself a 6 puck clutch, a better pressure plate and fly wheel, and if u have the funds replace the diff as well, quaife has pretty good stuff.
lowering the compression varies. if u lower it with pistons and rods(JE forged) and a copper head gasket, than that motor should be able to run at least 19 psi on 93 octane, if u were to lower the compression other wise, for example a cheap way is to stack head gaskets, the stock bottom end will only handle between 12-15 psi, it all depends on how u tune it, and drive it. with turbo car comes the endless dyno hours of tuning, be prepared for that. as far as the drivetrain goes, get urself a 6 puck clutch, a better pressure plate and fly wheel, and if u have the funds replace the diff as well, quaife has pretty good stuff.
The s2000 motor is very similar to a H series prelude motor. If you are serious about running boost. The motor must be sleeved. Just by using some pistons would not get you a high boost motor.
12-18-2003, 07:40 AM
#14
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Just a few items...
1) Copper head gasket although available is not recommended... it's like cutting your springs to lower your car in my opinion
2) One important factor in addition to the compression ratio is the fuel system: will you be using a rising rate fmu? larger fuel pump? stock injectors? the fuel system is a large part of the equation when deciding how much boost to run
3) Lowering your compression is indeed directly proportional to the amount of boost that you can run because the real important number is the "static compression ratio" which is the actual compression ratio in the cyls based on the bore and stroke combined with the amount of boost introduced
4) Jenner and others may have been or be running 10+ psi on stock internals but that's a proven recipe for disaster... believe me I know this to be true for a fact
5) With 10:1 pistons and sleeves as evoS2000 said your engine will be able to handle massive boost (likely in to the 25psi range saftely) but you need to refer to my point #2 because regardless of which engine setup you run, detonation will kill it
6) I've run 15psi easily with 93/94 octane gas having 9:1 pistons without having problems
7) Again, evoS2000 is right about your drivetrain... I've gone through 2 sets of half-shafts, a diff and a propeller shaft
8) Good luck with the project and keep us all informed of how you make out!
BS2KT
1) Copper head gasket although available is not recommended... it's like cutting your springs to lower your car in my opinion
2) One important factor in addition to the compression ratio is the fuel system: will you be using a rising rate fmu? larger fuel pump? stock injectors? the fuel system is a large part of the equation when deciding how much boost to run
3) Lowering your compression is indeed directly proportional to the amount of boost that you can run because the real important number is the "static compression ratio" which is the actual compression ratio in the cyls based on the bore and stroke combined with the amount of boost introduced
4) Jenner and others may have been or be running 10+ psi on stock internals but that's a proven recipe for disaster... believe me I know this to be true for a fact
5) With 10:1 pistons and sleeves as evoS2000 said your engine will be able to handle massive boost (likely in to the 25psi range saftely) but you need to refer to my point #2 because regardless of which engine setup you run, detonation will kill it
6) I've run 15psi easily with 93/94 octane gas having 9:1 pistons without having problems
7) Again, evoS2000 is right about your drivetrain... I've gone through 2 sets of half-shafts, a diff and a propeller shaft
8) Good luck with the project and keep us all informed of how you make out!
BS2KT
12-18-2003, 07:54 AM
#17
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nice Je has good stuff, i have je 8.5:1 comp pistons and pauter rods in my car as well, sorry it is not a honda , vw corrado 1.8 supercharged, the car felt like new after the piston and rod upgrade, had the crank knife edged as well. oh yeah copper head gasket with arp head studs. JE is a good investment in my opinion
12-18-2003, 10:41 PM
#18
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I asked the same question about why not lower the compression to 8:1. The answer I got back was that they would prefer the engine to make as much power under a normally aspirating condition and add to it by forced induction. The 8:1 is common for V8's but it is too much of a compromise on a 4 cylinder with a limited amount of torque under lower boost conditions.
12-19-2003, 01:50 AM
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could you guys explain what is meant by "crank knife edge"?
Can you guys tell me where I can get some more info on the JE pistons and pauter rods? Is the piston oval in shape or do I need to sleeve the head? How much for the setup?
Blacks2000Turbo, what injector would you recommend for a 9.5:1 compression with 11-13psi vortech?
Thanks in advance guys.
I am tip toeing toward lower compression forged pistons, strengthened rods and stock honda crank for my repair. I will then increase the vortech to 11 or 13 psi and tune it with an emanage. Does this sound good guys or is it bad?
Can you guys tell me where I can get some more info on the JE pistons and pauter rods? Is the piston oval in shape or do I need to sleeve the head? How much for the setup?
Blacks2000Turbo, what injector would you recommend for a 9.5:1 compression with 11-13psi vortech?
Thanks in advance guys.
I am tip toeing toward lower compression forged pistons, strengthened rods and stock honda crank for my repair. I will then increase the vortech to 11 or 13 psi and tune it with an emanage. Does this sound good guys or is it bad?
12-19-2003, 04:14 AM
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With regard to building your engine... don't take this the wrong way but you seem to have enough knowledge to be dangerous as they say. You know the buzz words and have a basic knowledge of what's going on but you're prime picking for someone to take advantage of you. Find an engine builder that you can trust to take care of the sleeves, rods, pistons, etc... Then find a tuner to work with you on the fuel system and / or ECU. For the kind of boost you're looking to run I would guess you would be good to go with something in the 550cc range but there are a lot of variables. I wouldn't recommend using Mike Simon for your motor work. Anyone who wants to know why can PM me and I'll fill you in on the details. He is not a stand up guy and definitely is not a reputable business man. That aside, good luck with your project.
-BS2KT
-BS2KT