cashsaudio Posted July 3, 2006 Report Share Posted July 3, 2006 Well i got it to run better but can't seem to get the turbo to boost pass 10psi its always average around 5-10psi. I have a Gt45 turbo with a 1.05 A/R exhaust side. I double check any leaks and didn't find anything my header flows really good. I have 160lb/hr injectors x4. MSII 3.0v with a 4 bar map sensor. I'm controling timing and fuel on it. Why the hell can't I get the turbo boosted pass 10psi. It acts like i have a leaky exhaust leak between head and turbo but i looked really close and try to hear any but didn't even notices anything. Do i need more fuel or less fuel? Timing? I'll post my info in abit, have to grab off of labtop. I change the req_fuel from 2.6 to 5.5 and made a huge difference. I got alot of low end power at the moment got stock head, valves, cam. Thinking putting my 292 cam in tonite see of that helps. Or is it just the turbo too damn big? help me out here guys. It idles awesome and revs just great. Jeff btw, my final timing is about 22 degree at about 300kpa 22 at 250kpa and 28 at 125kpa Link to comment Share on other sites More sharing options...
Boosted_One Posted July 3, 2006 Report Share Posted July 3, 2006 GT42 and 160lb injectors?? Good god how is it ideling?? That is a lot of turbo and fuel Jeff! The hotside A/R is huge too. When do you see boost like 4000-4500 rpms? Link to comment Share on other sites More sharing options...
ZPI28 Posted July 3, 2006 Report Share Posted July 3, 2006 Thats sounds like a Crap load of fuel there.. and thats a huge huffer you got on there. Same question // how does it idle? Link to comment Share on other sites More sharing options...
cashsaudio Posted July 3, 2006 Author Report Share Posted July 3, 2006 GT42 and 160lb injectors?? Good god how is it ideling?? That is a lot of turbo and fuel Jeff! The hotside A/R is huge too. When do you see boost like 4000-4500 rpms? Mike It idles awesome way better than before. Revs perfect I got alot of low end power but can never get the turbo to get pass 10psi. I start seeing boost about 3800 i think have to check my datalog. But even if its boosting at very high rpm it should at least boost fully right? Link to comment Share on other sites More sharing options...
button Posted July 3, 2006 Report Share Posted July 3, 2006 That big exhaust housing could play a roll in it. All the hot air is slowing down so much in that big a** housing. With a stand alone you should be able to make any injectors idle. what is your Afrs @ 10psi? without knowing that, its hard to say lean it out, but i would probably go that way. I kinda think you have too large of injectors anyways. by the time you need them you'll blow your head off the motor. what exhaust manifold are you running? too large of exhaust runners and too large of an exhaust housing would definately limit your boost. Also, is the wastegate held shut? if not, try tinkering with that as well. -Jay Link to comment Share on other sites More sharing options...
cashsaudio Posted July 3, 2006 Author Report Share Posted July 3, 2006 well what I'll do is put a plate on the wastegate see if it is leaking but i doubt it but its worth a try. You can tell if the wastegate opens by hearing it but never heard it. The T70 turbo exhaust side was .84 and would make that much of a difference? I have the Fuel pressure reg. set at about 28psi so i can lean it out better and worked. But i change my req fuel from 2.6 to 5.5 and ran even alot better. Maybe timing? I'm getting fustrated. This has to work. My header is about an average 18" long. just at idle the turbo spins alot faster than my T70 did so i thought this would be a great turbo. forgot to add i dunno what my afr is at 10psi. my O2 sensor doesn't even work (narrowband) got a new one and doesn't do anything even my gauge doesn't read anything that is located in my pod. I even try to put direct ground to the sensor to see if i get a reading nope. Link to comment Share on other sites More sharing options...
Boosted_One Posted July 3, 2006 Report Share Posted July 3, 2006 Honestly I think a .84 is as big as I would ever go. There is a huge difference from .84 to 1.05... heck there is a huge difference from a .70 to .84 A/R. Why your only making 10psi and not anymore...hmmm.. unless your WG spring is restricting you and the boost controlling is regualting it, or there is a leak in the WG area then I wonder if that turbo is just flat out too big. Your build up is something more that you would do on a Supra motor...and I wonder if that turbo is too big... I do think it is too big on the hotside. I just wonder if you need to rev it out higher to see more boost? What if that turbo needs 7000-8000 rpms to see full boost? In reality that T70 you had was pretty damn big as it was. Link to comment Share on other sites More sharing options...
lionbull Posted July 3, 2006 Report Share Posted July 3, 2006 Honestly I think a .84 is as big as I would ever go. There is a huge difference from .84 to 1.05... heck there is a huge difference from a .70 to .84 A/R. Why your only making 10psi and not anymore...hmmm.. unless your WG spring is restricting you and the boost controlling is regualting it, or there is a leak in the WG area then I wonder if that turbo is just flat out too big. Your build up is something more that you would do on a Supra motor...and I wonder if that turbo is too big... I do think it is too big on the hotside. I just wonder if you need to rev it out higher to see more boost? What if that turbo needs 7000-8000 rpms to see full boost? In reality that T70 you had was pretty damn big as it was. I agree that ar is more for rx-7. Who sold you that turbo anyway? Link to comment Share on other sites More sharing options...
cashsaudio Posted July 3, 2006 Author Report Share Posted July 3, 2006 well I figured that if i get a cam and valves and porting done and a better flow header that should spool up that GT45 as same as the T70 but only did the header. I got the motor up to about 7000k and still only see same boost the whole way. the wastegate wasn't leaking i checked by taking it off make sure there wasn't any leak (because I never even hooked it up to open). So i guess I'll get the T70 again and start from there. And get some 96lb/hr injectors. For someone that wants to run 2 160lb/hr injectors for TB injection would be perfect if they run MS I may give that a try. Link to comment Share on other sites More sharing options...
Boosted_One Posted July 3, 2006 Report Share Posted July 3, 2006 well I figured that if i get a cam and valves and porting done and a better flow header that should spool up that GT45 as same as the T70 but only did the header. I got the motor up to about 7000k and still only see same boost the whole way. the wastegate wasn't leaking i checked by taking it off make sure there wasn't any leak (because I never even hooked it up to open). So i guess I'll get the T70 again and start from there. And get some 96lb/hr injectors. For someone that wants to run 2 160lb/hr injectors for TB injection would be perfect if they run MS I may give that a try. If you need that much fuel the 8 injector setups are the ticket. Even 96lbers are huge... I bet 85lbers will be more than enough. Actually more porting, bigger valves, etc that [in theory] could cause the turbo to spool slower. The merit of porting, larger valves, etc is to gain upper end flow. When your dealing with a turbo that size every bit matters to get it online. You'd be surprised what kind of power curve there is in the .63 - 84 hot side A/R. Just look at all the big guns here. Link to comment Share on other sites More sharing options...
smog Posted July 3, 2006 Report Share Posted July 3, 2006 get a wideband first of all. and make usre its working cortrectly on the ms. Retarding your timing quite a ibt will help spool the turbo quicker, although isnt optimum for power. You may want to play around with that to see if you can get any more boost out of the car. As for the 1.06ar, you should be able to spool it, although thats way more than anything but maybe a 800hp drag car would want. I think you would need to spray to get that thing going good also. Seemed weird that you can build 10lbs but it wont climb, if you start building boost, you should keep building it. Get your a/f in check, i'd start at 11.0 to start and maybe richen it up a bit towards the top end, like 10.5, very conservativem then start to lean it out untill you feel its no longer safe. If you bought a cheap external, that could be your problem too. I'd also looking into getting a custom high lift cam made, something with .500 or more lift, and a very good port job. You aer obviously not looking for any low end, so the .500 should reallly improve up top. Link to comment Share on other sites More sharing options...
cashsaudio Posted July 4, 2006 Author Report Share Posted July 4, 2006 okay I put my 294 cam in and had to advance the cam one tooth but might have to do one more then should be good. But I have notices ALOT more pressure through the exhaust then the last cam. And not running really all that rich like it did before. Will be taking it out for a spin tomorrow to see what it does. Link to comment Share on other sites More sharing options...
cashsaudio Posted July 4, 2006 Author Report Share Posted July 4, 2006 Okay what you guys think I should get the same o 75lb that i had before or 84's or 96? I want to get at least 500HP and still awaiting on my damn. cylinder head. Link to comment Share on other sites More sharing options...
artinist Posted July 6, 2006 Report Share Posted July 6, 2006 that exh. housing is wayyyyy too big and you have injectors to launch a sputnic Link to comment Share on other sites More sharing options...
Boosted_One Posted July 6, 2006 Report Share Posted July 6, 2006 Knock your A/R down to .63 - .84'ish Get some smaller injectors.Degree your cam.Give that turbo all its supporting mods and then try it out. Man dude you could have talked to me I would have helped ya... told ya before you bought all that stuff. If you didn't want me to say what ya had just say that... That turbo is going to need a smaller hotside to get that coldside online. What size is your turbine trim?? If that is huge you are going to have to run a small a/r to offset that a bit. Link to comment Share on other sites More sharing options...
Highly Boosted Posted July 7, 2006 Report Share Posted July 7, 2006 dude that sucks jeff. But look on the bright side my car will be running soon lol what I mean is that I will come over and give you a hand if you need it. Sorry about that some times i can be mean. Link to comment Share on other sites More sharing options...
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