built dohc zc with 8:1 compression, suggest turbo for setup.
#1
built dohc zc with 8:1 compression, suggest turbo for setup.
I built my dohc zc for boost so I wanted to run lower compression (so when i wanna up the boost), but i made a huge mistake when selecting the (srp)pistons!!! i thought my new compression would be 8.8:1 but thats becaused i made a mistake when i used the compression calculator, I ended up with a 8:1 compression!!!!...so now im not sure on what turbo would be a good fit for the car?
setup:
-dohc zc/ si trans.(6 puck act clutch)
-eagle rods, srp pistons
-delta regrind cams, kms valves,springs,retainers....i cant remember(brand name of) my cam gear's
-new oem gaskets/seals and belts (cant remember brand of) bearings
-chipped pr4 ecu (xenocron base map), dsm blue top injectors
-2.5 inch cat back exhaust and turbo piping
-7 inch jrc intercooler, "greddy type" bov
right now i only have an hf manifold (would like to still use this for the time being, with a turbo with the right power) and i was gonna use a saab t3 turbo but im thinking that might be too small with my compression ---- up ( i had a t25 on my zc when it was stock and that was too small)
with all the info above....what turbo would you reccomend to make up for the way low compression ( i dont wanna get new pistons, so im thinking more boost would work)
setup:
-dohc zc/ si trans.(6 puck act clutch)
-eagle rods, srp pistons
-delta regrind cams, kms valves,springs,retainers....i cant remember(brand name of) my cam gear's
-new oem gaskets/seals and belts (cant remember brand of) bearings
-chipped pr4 ecu (xenocron base map), dsm blue top injectors
-2.5 inch cat back exhaust and turbo piping
-7 inch jrc intercooler, "greddy type" bov
right now i only have an hf manifold (would like to still use this for the time being, with a turbo with the right power) and i was gonna use a saab t3 turbo but im thinking that might be too small with my compression ---- up ( i had a t25 on my zc when it was stock and that was too small)
with all the info above....what turbo would you reccomend to make up for the way low compression ( i dont wanna get new pistons, so im thinking more boost would work)
#3
Re: built dohc zc with 8:1 compression, suggest turbo for setup.
Originally Posted by J.H.Christ
holset h1c with 12 cm housing
anyone else reccomend a turbo to help with my low compression?
#5
Re: built dohc zc with 8:1 compression, suggest turbo for setup.
Originally Posted by 2stockrocketz
any chance i can run that with an hf mani?(for temp. fix.... i need to get my car out of state)
anyone else reccomend a turbo to help with my low compression?
anyone else reccomend a turbo to help with my low compression?
#6
Re: built dohc zc with 8:1 compression, suggest turbo for setup.
Genuine Garrett T3/T4. Any of the stage 1 turbine variants. T3/TO4B would be great. T3/TO4E if you'll be revving out high, or even T3/TO4S (comes with stage 3 turbine) if you're going ***** out. It really depends on what your goals are, but even the T3/TO4B can crush 400whp.
#7
Re: built dohc zc with 8:1 compression, suggest turbo for setup.
Low CR won't make a big difference in turbo selection, you just have to crank the boost controller a bit more to make the same power as a higher CR setup, BUT you are a lot more detonation resistant which is a great thing with a 75mm bore.
What DOES make a difference is cam selection vs CR. The Crower stage 2 turbo cam is GOD at 9-10:1 CR, but at 7.8:1 CR is too much cam and causes a power loss (car had other issues, so I might be wrong about that). I know that running big all motard cams that work on 2.0 B-series freaking suck on B16 and cause issues, and am transferring that concept onto D-series.
All part of my grand unified theory about why stock Z6 cam and 7.8:1 CR Vitara setups do not suck and make great power, a stock cam that is not bad per se but is slightly restrictive works better with low CR. When I have conclusive proof I'll talk more about the subject. :P
If you are dealing with Delta 272's then you should be fine. If bigger you may still be fine, Delta won't stick you with a cam that sucks for boost, but you will *definitely* have to play with your cam gears to get them to work really well.
What DOES make a difference is cam selection vs CR. The Crower stage 2 turbo cam is GOD at 9-10:1 CR, but at 7.8:1 CR is too much cam and causes a power loss (car had other issues, so I might be wrong about that). I know that running big all motard cams that work on 2.0 B-series freaking suck on B16 and cause issues, and am transferring that concept onto D-series.
All part of my grand unified theory about why stock Z6 cam and 7.8:1 CR Vitara setups do not suck and make great power, a stock cam that is not bad per se but is slightly restrictive works better with low CR. When I have conclusive proof I'll talk more about the subject. :P
If you are dealing with Delta 272's then you should be fine. If bigger you may still be fine, Delta won't stick you with a cam that sucks for boost, but you will *definitely* have to play with your cam gears to get them to work really well.
#8
Re: built dohc zc with 8:1 compression, suggest turbo for setup.
Originally Posted by Joseph Davis
Low CR won't make a big difference in turbo selection, you just have to crank the boost controller a bit more to make the same power as a higher CR setup, BUT you are a lot more detonation resistant which is a great thing with a 75mm bore.
What DOES make a difference is cam selection vs CR. The Crower stage 2 turbo cam is GOD at 9-10:1 CR, but at 7.8:1 CR is too much cam and causes a power loss (car had other issues, so I might be wrong about that). I know that running big all motard cams that work on 2.0 B-series freaking suck on B16 and cause issues, and am transferring that concept onto D-series.
All part of my grand unified theory about why stock Z6 cam and 7.8:1 CR Vitara setups do not suck and make great power, a stock cam that is not bad per se but is slightly restrictive works better with low CR. When I have conclusive proof I'll talk more about the subject. :P
If you are dealing with Delta 272's then you should be fine. If bigger you may still be fine, Delta won't stick you with a cam that sucks for boost, but you will *definitely* have to play with your cam gears to get them to work really well.
What DOES make a difference is cam selection vs CR. The Crower stage 2 turbo cam is GOD at 9-10:1 CR, but at 7.8:1 CR is too much cam and causes a power loss (car had other issues, so I might be wrong about that). I know that running big all motard cams that work on 2.0 B-series freaking suck on B16 and cause issues, and am transferring that concept onto D-series.
All part of my grand unified theory about why stock Z6 cam and 7.8:1 CR Vitara setups do not suck and make great power, a stock cam that is not bad per se but is slightly restrictive works better with low CR. When I have conclusive proof I'll talk more about the subject. :P
If you are dealing with Delta 272's then you should be fine. If bigger you may still be fine, Delta won't stick you with a cam that sucks for boost, but you will *definitely* have to play with your cam gears to get them to work really well.
#9
Re: built dohc zc with 8:1 compression, suggest turbo for setup.
(damn i used to be on hmt allmost daily, since its been so long... i feel like a noob )
well when i started the build (back in school) my goal was to be over 250 whp, but ---- came up and now i just need the have the car drivable (from san diego to las vegas) so i dont have to leave my broken down civic in the middle of the desert .
Im looking for a turbo that will power the car(engine setup) without out being pushed to its limits(maxed out) (i.e. I want the car to drive fine(not feel like a snail) and then still have power to pull....when i wanna go faster) but i dont need to hit 300whp all the time
as for my cams, I ordered the combo set up 272/260 (guy from delta reccomended this for my set up) this is a lil section about my cams (from the zcr):
260 Profile
Advertise Duration: Int=260 / Exh=260
Duration @ .050: Int=NA / Exh=NA
Lobe Separation: NA
Gross lift: 400/400
272 Profile
Advertise Duration: Int=272 / Exh=272
Duration @ .050: Int=NA / Exh=NA
Lobe Separation: NA
Gross lift: 425/425
the 'tech guy' said that the 260 was designed to be just a stock replacement without having too many aftermarket bolt-ons, where the 272 works better with modifications.
also the 260 out-accelerates the 272 till ~3500rpm where the 272 out-performs.
and I hear ya about messing with the cam gears.... that was a problem just to get the engine idling right.
we all know this is hmt (so i probaly dont have to say this, but....) but i need a turbo that wont cost more then my build.
thanks for all the much needed help guys
Originally Posted by crx2211
Genuine Garrett T3/T4. Any of the stage 1 turbine variants. T3/TO4B would be great. T3/TO4E if you'll be revving out high, or even T3/TO4S (comes with stage 3 turbine) if you're going ***** out. It really depends on what your goals are, but even the T3/TO4B can crush 400whp.
Originally Posted by Joseph Davis
Low CR won't make a big difference in turbo selection, you just have to crank the boost controller a bit more to make the same power as a higher CR setup, BUT you are a lot more detonation resistant which is a great thing with a 75mm bore.
If you are dealing with Delta 272's then you should be fine. If bigger you may still be fine, Delta won't stick you with a cam that sucks for boost, but you will *definitely* have to play with your cam gears to get them to work really well.
If you are dealing with Delta 272's then you should be fine. If bigger you may still be fine, Delta won't stick you with a cam that sucks for boost, but you will *definitely* have to play with your cam gears to get them to work really well.
as for my cams, I ordered the combo set up 272/260 (guy from delta reccomended this for my set up) this is a lil section about my cams (from the zcr):
260 Profile
Advertise Duration: Int=260 / Exh=260
Duration @ .050: Int=NA / Exh=NA
Lobe Separation: NA
Gross lift: 400/400
272 Profile
Advertise Duration: Int=272 / Exh=272
Duration @ .050: Int=NA / Exh=NA
Lobe Separation: NA
Gross lift: 425/425
the 'tech guy' said that the 260 was designed to be just a stock replacement without having too many aftermarket bolt-ons, where the 272 works better with modifications.
also the 260 out-accelerates the 272 till ~3500rpm where the 272 out-performs.
and I hear ya about messing with the cam gears.... that was a problem just to get the engine idling right.
we all know this is hmt (so i probaly dont have to say this, but....) but i need a turbo that wont cost more then my build.
thanks for all the much needed help guys