Direct bolt-on turbo (ko4 replacement)
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lolNow I do personally agree that something bigger than a 2871 or efr6758 is a little much for a fwd car, but to each their own really. If someone wants to make a 600whp straight line car or dyno queen, then all the more power to them (no pun intended.. lol).
on e47 you should get good numbers.
im sticking with the k04 for simplicity and because of class regulations. im not a fan of the zfr housing after installing a few of these. i havent had luck with the bolts they supplied(this was in one housing and couldnt get them tight to my liking without stripping them so i tossed them and replaced them with better stuff on the next 3 ive done) and i feel they could be higher grade and the i had a set of lines that werent even close that i had to bend a whole lot to get to work(again not a huge deal). the housing itself is really nice minus the fact its not threaded for studs. i personally run my car at high rpms a lot and i would like to retain my heatshield setup on the manifold and it makes its almost(it can be done) impossible to tighten a nut down there depending on how you cut the manifold shield. other then that i was happy with the product in terms of the housing fitment and such.
personally for a front driver a 6258 is perfection imho but due to class restrictions and what not i feel the k04 will benefit me more and give me more points to play with in other aspects. we are going to try one out of the new track car and see how it does in terms of getting reclassed. some might look at a 6258/6758 and be like oh hey that things capable of 450/500 max flow bla bla bla and the reclass might be a lot higher then a k04+.
just my 2 cents there. ive always tried to build a well balanced car regardless of the power it puts down. i personally even though my cobalt now wont ever touch the black car in terms of what it did for power it will out do it in every other car in terms of being a clean and well prepped street/track car. if someone wants to make 600whp and go straight or get dyno numbers go for it. thats just not for me. had my straightline fun years ago. i realized you dont need power to have an impressive car and focus on driver skill and proper setup has become a huge deal to me.
im sticking with the k04 for simplicity and because of class regulations. im not a fan of the zfr housing after installing a few of these. i havent had luck with the bolts they supplied(this was in one housing and couldnt get them tight to my liking without stripping them so i tossed them and replaced them with better stuff on the next 3 ive done) and i feel they could be higher grade and the i had a set of lines that werent even close that i had to bend a whole lot to get to work(again not a huge deal). the housing itself is really nice minus the fact its not threaded for studs. i personally run my car at high rpms a lot and i would like to retain my heatshield setup on the manifold and it makes its almost(it can be done) impossible to tighten a nut down there depending on how you cut the manifold shield. other then that i was happy with the product in terms of the housing fitment and such.
personally for a front driver a 6258 is perfection imho but due to class restrictions and what not i feel the k04 will benefit me more and give me more points to play with in other aspects. we are going to try one out of the new track car and see how it does in terms of getting reclassed. some might look at a 6258/6758 and be like oh hey that things capable of 450/500 max flow bla bla bla and the reclass might be a lot higher then a k04+.
just my 2 cents there. ive always tried to build a well balanced car regardless of the power it puts down. i personally even though my cobalt now wont ever touch the black car in terms of what it did for power it will out do it in every other car in terms of being a clean and well prepped street/track car. if someone wants to make 600whp and go straight or get dyno numbers go for it. thats just not for me. had my straightline fun years ago. i realized you dont need power to have an impressive car and focus on driver skill and proper setup has become a huge deal to me.
well said Matt, i decided to go with the wr-1 also because i wanted a more balanced car. Traction is a problem already in full boost situations on 24psi, and just bumping another 15% in power with the wr-1 will be enough, and a bit more manageable than a 425hp tire fryer. I have nothing against those wanting max power, but i would like more piece of mind on the tranny and clutch with the wr-1. I am looking forward to the one you guys have in the mail for me. If i was going to live at the dragstrip i would be one of those going max power, provided i had a spare trans sitting in the garage. To each his own.
I was able to keep my exhaust manifold heat shield on but it took a little of forcing to get the turbo to bolt up. It was tough at first but once we got it started on the Mani, it slid back and then tightened it up.
I went with the Zfr cause I wanted a safe, reliable, dd that is capable of low 12s-high 11s. The best part is the gas mileage and that its basically an unbelievable, underestimated sleeper. No one ever expects the power it has.
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I went with the Zfr cause I wanted a safe, reliable, dd that is capable of low 12s-high 11s. The best part is the gas mileage and that its basically an unbelievable, underestimated sleeper. No one ever expects the power it has.
Sent from my Samsung Galaxy S4 using CobaltSS
Yep I had a 6758 before and iI was happy with it but like turbos operating awards the top of their efficiency range. I push my cars. After making 416whp on shitty winter 93 i knew what the could do. I still wanted slightly better response and I wanted 400 whp on the money a 6258 would of gave me what iI wanted but it came down to getting my car rec classed and the ear being able to hold more power would of probably rec classed me higher then what I want.
Not sayigreater. e zfr isbad. the Idea is grearThere was just miniscule little crap that tuns me off it. I recommend people ceramic coat the housing being that its a mild steel cast as well to protect it against corrosion
Not sayigreater. e zfr isbad. the Idea is grearThere was just miniscule little crap that tuns me off it. I recommend people ceramic coat the housing being that its a mild steel cast as well to protect it against corrosion
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on e47 you should get good numbers.
im sticking with the k04 for simplicity and because of class regulations. im not a fan of the zfr housing after installing a few of these. i havent had luck with the bolts they supplied(this was in one housing and couldnt get them tight to my liking without stripping them so i tossed them and replaced them with better stuff on the next 3 ive done) and i feel they could be higher grade and the i had a set of lines that werent even close that i had to bend a whole lot to get to work(again not a huge deal). the housing itself is really nice minus the fact its not threaded for studs. i personally run my car at high rpms a lot and i would like to retain my heatshield setup on the manifold and it makes its almost(it can be done) impossible to tighten a nut down there depending on how you cut the manifold shield. other then that i was happy with the product in terms of the housing fitment and such.
personally for a front driver a 6258 is perfection imho but due to class restrictions and what not i feel the k04 will benefit me more and give me more points to play with in other aspects. we are going to try one out of the new track car and see how it does in terms of getting reclassed. some might look at a 6258/6758 and be like oh hey that things capable of 450/500 max flow bla bla bla and the reclass might be a lot higher then a k04+.
just my 2 cents there. ive always tried to build a well balanced car regardless of the power it puts down. i personally even though my cobalt now wont ever touch the black car in terms of what it did for power it will out do it in every other car in terms of being a clean and well prepped street/track car. if someone wants to make 600whp and go straight or get dyno numbers go for it. thats just not for me. had my straightline fun years ago. i realized you dont need power to have an impressive car and focus on driver skill and proper setup has become a huge deal to me.
im sticking with the k04 for simplicity and because of class regulations. im not a fan of the zfr housing after installing a few of these. i havent had luck with the bolts they supplied(this was in one housing and couldnt get them tight to my liking without stripping them so i tossed them and replaced them with better stuff on the next 3 ive done) and i feel they could be higher grade and the i had a set of lines that werent even close that i had to bend a whole lot to get to work(again not a huge deal). the housing itself is really nice minus the fact its not threaded for studs. i personally run my car at high rpms a lot and i would like to retain my heatshield setup on the manifold and it makes its almost(it can be done) impossible to tighten a nut down there depending on how you cut the manifold shield. other then that i was happy with the product in terms of the housing fitment and such.
personally for a front driver a 6258 is perfection imho but due to class restrictions and what not i feel the k04 will benefit me more and give me more points to play with in other aspects. we are going to try one out of the new track car and see how it does in terms of getting reclassed. some might look at a 6258/6758 and be like oh hey that things capable of 450/500 max flow bla bla bla and the reclass might be a lot higher then a k04+.
just my 2 cents there. ive always tried to build a well balanced car regardless of the power it puts down. i personally even though my cobalt now wont ever touch the black car in terms of what it did for power it will out do it in every other car in terms of being a clean and well prepped street/track car. if someone wants to make 600whp and go straight or get dyno numbers go for it. thats just not for me. had my straightline fun years ago. i realized you dont need power to have an impressive car and focus on driver skill and proper setup has become a huge deal to me.
While I do agree there is a limit especially for a fwd car, I don't think that a k04+ or even 6258 is the limit. Neither the 6258 or 6758 are big turbos in the least. As a matter of fact, they're still quite small. You also really have to push the 6258 pretty hard to make close to 400whp. It's just far more efficiently done with something like a 2871 or 6758 imo. Also, who's to say you need to push either turbo to it's limit? If you want a milder setup, just tune it accordingly.
As far as outgrowing the desire for more power. I'm 32 now and still have no desire to tame it down. I guess I just never grew up..
As far as power goes...i'll be tuning for 400whp on 93 and 5-525whp on e85. I will be balancing the car out once the power is there. And i get more money lol. Unfortunately im about to move into a house that i scrape going in the driveway at stock ride height.
Idk man. I personally had no issues with reusing all of my heat shields (mani, turbo and o2 housing shields) but I can't speak for everyone of course.
While I do agree there is a limit especially for a fwd car, I don't think that a k04+ or even 6258 is the limit. Neither the 6258 or 6758 are big turbos in the least. As a matter of fact, they're still quite small. You also really have to push the 6258 pretty hard to make close to 400whp. It's just far more efficiently done with something like a 2871 or 6758 imo. Also, who's to say you need to push either turbo to it's limit? If you want a milder setup, just tune it accordingly.
As far as outgrowing the desire for more power. I'm 32 now and still have no desire to tame it down. I guess I just never grew up..
While I do agree there is a limit especially for a fwd car, I don't think that a k04+ or even 6258 is the limit. Neither the 6258 or 6758 are big turbos in the least. As a matter of fact, they're still quite small. You also really have to push the 6258 pretty hard to make close to 400whp. It's just far more efficiently done with something like a 2871 or 6758 imo. Also, who's to say you need to push either turbo to it's limit? If you want a milder setup, just tune it accordingly.
As far as outgrowing the desire for more power. I'm 32 now and still have no desire to tame it down. I guess I just never grew up..
i dont consider the 6258/6758 big at all.. . they are physically big but thats about it. i have no problem pushing the turbo. like i said i do a lot of road racing. more of less what im getting at is that when you come out of a turn or you have a shikane or something of the sort you want to get your power and get it quickly. i dont want to have to respool the turbo or have a huge torque hit at 4k wiht something large in a fwd car. if it was awd or rwd big powers a lot easier to run.
im 24.... ive had cars all over the map from no power to lots of power. i drag raced most of my life and i worked for a top fuel team. making all this power in a cobalt just isnt for me anymore. i daily drive the car and track it. the black cobalt made 442whp 450 ftlbs at 25psi on 93 @ 6200. it was way more then what i wanted but we wanted to get our percision kit done. the efr made 416whp 427 ft lbs at 25 psi @6500 high 300s or right at 400 is perfect for this car. like is said im mainly debating the k04+ because of class regulation.
not trying to knock peoples goals. to each is their own what they wanna do.
^^^i hear ya. I agree with what youre saying. If thats what i did with my car i would probably do the exact same thing. I dd mine too. I have 122k on my hhr
i still love the acceleration rush. Just my cup of tea. But as you said to each their own
i still love the acceleration rush. Just my cup of tea. But as you said to each their own
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OMIOTEK,
Why don't you use the WR-2 and show us what kind of power/powerband It has?
I'm surprised you didnt suggest it to anyone since you are saying 400whp is perfect for our cars, and that's the wheelhouse of that turbo with quick spooling correct?
Why don't you use the WR-2 and show us what kind of power/powerband It has?
I'm surprised you didnt suggest it to anyone since you are saying 400whp is perfect for our cars, and that's the wheelhouse of that turbo with quick spooling correct?
it flows 45-47lbs a min but will choke out around 6500 because of the littler compressor housing. so it will only make power to 6300-6500. now if you got the type b option it will flow that to 7000.
theres just no point in me getting the turbo just because to show the world what it can do. im just an employee here and money still has to come out of my pocket for it. its not the turbo I want so I cant justify spending the cash on it knowingly I want something different. the wr1 is less then what I want but will give me enough and as I explained with class regulation it will put me where I want...
