Marcus18 Posted February 22, 2004 Report Share Posted February 22, 2004 can I turn the boost up to say 13psi? or will I run outta fuel? if so will turning up the fuel pressure help? this would be done after I get a transmission in it. marcus Quote Link to comment Share on other sites More sharing options...
god910 Posted February 22, 2004 Report Share Posted February 22, 2004 I'm running about 15 (accidentally) It doesn't act "perfect" but not bad. I am running a custom chip though, so, can't tell you bout chore chip. Quote Link to comment Share on other sites More sharing options...
dkorinko Posted February 22, 2004 Report Share Posted February 22, 2004 Im doing great at 15! Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted February 22, 2004 Author Report Share Posted February 22, 2004 are you using stock injectors? marcus Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted February 22, 2004 Author Report Share Posted February 22, 2004 ...if I trick the map into thinking I'm at 11.5 psi while I'm at 13 it will lean out right? I have to find a way around fuel cut. I would like atleast 1 psi more. will the tg160 handle this jeff? marcus Quote Link to comment Share on other sites More sharing options...
dkorinko Posted February 22, 2004 Report Share Posted February 22, 2004 are you using stock injectors? marcus sadly enough.....yes Quote Link to comment Share on other sites More sharing options...
dbtk2 Posted February 22, 2004 Report Share Posted February 22, 2004 The topgun's fuel cut is set way too low IMO. You won't have much luck doing much of anything to raise boost with it, even if the fuel system could handle it. On our 2 door TGP in 20 degree weather with all stock boost controller and everything it wil hit the fuel cut, its kinda annoying, and doesn't make much sense. I understand having the fuel cut to prevent people from running too much boost and damaging the engine, but if it hits fuel cut without any way of raising boost, the fuel cut is a little too low. I have no idea how much boost that is, because it just has the stock gauge. But, in the summer in like 70 degree weather I tried using my modified boost controller with a very small hole drilled in it to leak a little vacuum (adds about .75psi on my stock chipped STE), and it worked fine if you just went from a stop and went through the gears like that. But if you went WOT on the highway and got the revs out of the powerband, it would bog down in 3rd gear like it wasn't getting any timing (it would be getting PLENTY of boost), and if you were going like 30 and went to pass someone it would be revving too low in 2nd gear and would try to get too much boost and would hit the fuel cut. The car didn't really feel any quicker with the raised boost either, I just don't think the fuel system can handle it, or Jeff programs the chip to pull a lot of timing. Maybe with larger injectors or something. I would talk to Jeff (or maybe someone else the programs chips) about a custom tune (if he is willing to make one) if you want to run more boost, that is really the only right way to do it IMO. Shawn Quote Link to comment Share on other sites More sharing options...
Jeff M Posted February 22, 2004 Report Share Posted February 22, 2004 can I turn the boost up to say 13psi? or will I run outta fuel?if so will turning up the fuel pressure help? this would be done after I get a transmission in it. marcus For your engine’s and transmission’s safety I would not suggest 13 psi, or more! To clear up a confusion, Dkorinko has some leftover custom chips from the previous owner who was running 100 octane at the track and had a head and cam upgrade (stock turbo), those were some custom chips I did when I had the time to do something small like that, small meaning few people had interest as compared to a street chip for 92 octane/TopGun etc AND something that would not wear out the tranny in a hurry, though the original owner had something like 350 ¼ runs, but like anything, a 13-14 year old tranny is not going to take kindly to such huge amounts of power all the time, and is another reason why the street version TopGun chips are run at more reasonable and safer power levels. If people were reading the posts I have done and others about backpressure and the effects, and negative effects to the engine and to power gains, 13 psi and up would not be something people would be looking for at all for their stock turbo. But more so back to the engine with stock fueling and stock turbo, up to 12 psi is all that is safe for 92 octane and making max power, period! And 12 psi is all that the boost tables in the TopGun will run, push it past that and you will find the fuel cut there to save your ass, and timing taking down to avoid detonation to once again, save your ass! Can someone add some octane and be safe past 12 psi, somewhat but its that backpressure problem the stock and even upgraded turbos (so far) have that will cause problems you do not want! Those running into the fuel cut are having some amount of bleeding OR effects from having a bleed/manual control device in line causing their boost to get too high, or running too much boost for the lower rpms that will put a huge strain on the transmission and are finding some low timing values there once again, to save your ass/tranny. But more on the boost levels to tranny life point, the tranny would like the power to come on gradually, and if boost is ramped within these parameters as they are setup in the TopGun chip then traction is also controlled, which is a win-win scenario for both tranny life and traction that I worked a lot on. I am hearing from some people that their TopGun chip does not smoke the tires all the way or most of the way through 1st gear, first off the obvious to me is the abuse the tranny is taking (and the eventual bitchen we will hear back when it fails: “piece of shit TGP, someone needs a huge savings to keep these cars runningâ€Â) but more so if it matters to someone to be quick/fast is, spinning tires is NOT being fast :!: I had a local TGP owners who got beat by a stock Grand Am 3100, he called and bitched about his car, so I ask him to come over and we would check him out, and with me in the passenger’s seat I said show me your launch (and I was running a scan tool to check things AND a G-Tech Pro to check his 0-60 times!), he just floored it and spun though most of 1st gear, I asked if this was the way he raced and he said YES. SO we swapped places and I showed him a little traction control trick to do at takeoff/out of the hole, and after this 0-60 run I knocked off 6 tenths of a second!!! Only losers smoke their tires is what I told him, no more complaints about his car/my chip at being slow . So bottom line, 12 psi is max with 92 octane and safe running, quantity of fuel does not matter. Next is the backpressure problem with the stock turbo or even a few T28s I have tested, too much and not worth running (at least until we can get a turbine housing to exhale!)! Last is keeping it all together, safety above all else unless you have a lot of spare cars and spare cash and spare time . Jeff M Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted February 23, 2004 Author Report Share Posted February 23, 2004 hmmm. well transmission life isn't a big deal right now as I'm puting a brand new 13K mile 4t60-e in it. I haven't gone into it yet but I'm going to try and put the electrical guts and tv cable from the 4t60 and swap it into the 4t60-e downgrading it to work with my computer. if I can't swap the guts I'll manually shift it with two switches. the 4t60-e is from my 3800 s/c engine so it should be able to handle the power. I run 93 octane around here. what are your thoughts on making a adjustable from inside MBC? I was think of making one with two settings 7psi for driving and tranny life and 11.5psi for racing(since past 12 is bad). I do like the slow boost ramp as I like to punch it off the line. I've lost a race due to spinning in the past. is there any chance of you making a chip with the timing and fuel curve for say 20 psi? just a base chip so we could run an AFC and boost controller to adjust everything to are personal specs(such as p&p heads, bigger turbo, bigger injectors ect.) also.....spare cars....come see my yard. thanks for your input and time. marcus Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted February 23, 2004 Author Report Share Posted February 23, 2004 well atleast 14.7 since 20 would work with a 2 bar. marcus Quote Link to comment Share on other sites More sharing options...
skalor Posted February 23, 2004 Report Share Posted February 23, 2004 or running too much boost for the lower rpms that will put a huge strain on the transmission and are finding some low timing values there once again, to save your ass/tranny. But more on the boost levels to tranny life point, the tranny would like the power to come on gradually, and if boost is ramped within these parameters as they are setup in the TopGun chip then traction is also controlled, which is a win-win scenario for both tranny life and traction that I worked a lot on. So, you're saying that the boost control tables are only there mostly for tranny life?? So, the the boost control tables can be made more aggressive and engine life will not suffer. I've heard others state that too much boost too fast can result in detonation, is this true?? Josh Quote Link to comment Share on other sites More sharing options...
dbtk2 Posted February 23, 2004 Report Share Posted February 23, 2004 Jeff, Lets say I wanted to buy just a normal topgun 160 chip, but with the fuel cut raised about a 1/2 psi, and the timing tables to handle it? Could you do that for me, or would it be too much work? I just don't want to be running into any fuel cut problems like I have with our other TGP. It has the topgun 160, 160 t-stat, k&n filters, removed cat, and different mufflers, and in 20 degree or colder weather it hits the fuel cut. We always run at least 93 octane in it, usually 94 octane, and it pulls HARD until it hits the fuel cut. It has a new stock boost controller, new vacuum lines, and a rebuilt turbo installed all within the last 6 months. So when you say this: Those running into the fuel cut are having some amount of bleeding OR effects from having a bleed/manual control device in line causing their boost to get too high I am not sure it is the truth. I am thinking that when it gets down to 20 degrees, that with the K&N filter, better flowing exhaust, and new turbo that will spool easily, that it is just making that much boost, I am pretty sure it doesn't have any bleeding. Maybe I am wrong, but I think raising the fuel cut .5psi would be nice just to avoid any problems people might be having with this. Thats my opinion on it anyways. Shawn Quote Link to comment Share on other sites More sharing options...
Jeff M Posted February 23, 2004 Report Share Posted February 23, 2004 hmmm. well transmission life isn't a big deal right now as I'm puting a brand new 13K mile 4t60-e in it. I haven't gone into it yet but I'm going to try and put the electrical guts and tv cable from the 4t60 and swap it into the 4t60-e downgrading it to work with my computer. if I can't swap the guts I'll manually shift it with two switches. the 4t60-e is from my 3800 s/c engine so it should be able to handle the power. I run 93 octane around here. what are your thoughts on making a adjustable from inside MBC?I was think of making one with two settings 7psi for driving and tranny life and 11.5psi for racing(since past 12 is bad). I do like the slow boost ramp as I like to punch it off the line. I've lost a race due to spinning in the past. is there any chance of you making a chip with the timing and fuel curve for say 20 psi? just a base chip so we could run an AFC and boost controller to adjust everything to are personal specs(such as p&p heads, bigger turbo, bigger injectors ect.) also.....spare cars....come see my yard. thanks for your input and time. marcus Double ummmm. I wish you were asking about that tranny!! The 4T60E is a good tranny, upgraded to a 4T60E-HD is better though, some hardened parts in there that something like this turbo engine would benefit from, but the stock TGP Tranny has the hardened parts it needs to survive, and if you remember the great (not for the owner) photos of a non-TGP tranny with the large hole in the side of the case, might be making sure you are covered for your turbo baby 8) . No matter what you run, traction will still be the thing you lose running more aggressive boost at low rpms least you be running something like Nitto Drag Radials all the time (I am so I am guilty). So the concept of a dual stage is a good idea, what I found was just a little less use of the gas pedal and traction can be controlled pretty easy, need a tip, try this but not in a race, too much pressure on the driver to keep the pressure/boost off the engine When ready to take off, floor it, keep it there and get used to finding where it likes to lose traction, then stop and punch it again but this time lift off the gas pedal right about when the tires start to break, then push the pedal back down (depending on your tire’s traction) faster if you can get away with it, slower if not, do a little practicing to find the timing and balance, and once you do it a few times, you will find a link to your tires that will become second nature and require less thought, and more time for fun! As for a 20 psi chip (I am going to love the replies) its doable even with the 2 bar map sensor, I myself ran 17 to 18 psi and 100 octane for 3 months (sorry the rest of you guys heard me say this a few times in the past), but the temps were less than 50 degrees out and I ran with a scan tool setup knock sensor alert to save my ass. But 20 psi, hell 15 psi out of this stock turbo is making way too much heat, and near 20 psi is near or at what is called a surge condition where the turbo is spinning somewhat out of control (NOT good), even with a huge intercooler 15 to 20 psi is a lot to ask of the stock turbo. Back to what should get me some flack, 15 to whatever psi you want is doable with the stock 2 bar map sensor, not that I condone this concept, but the fueling and timing tables still have a value left in them when the boost values go past the sensors range, the computer just uses the last value it saw, same for timing and running rpms higher than 4,800 (the limit in the timing table), it just uses the last known value! So what do you do, set you last values in the fuel and timing table for what is tested safe at the max boost you want (17 or 18 or psi), also once you move the fuel cut up it is not looked at/not 15 psi! As for boost levels and all that, thanks for asking, good question, here is info from my reference books compiled from GM, Bosch and some others. Since on our planet we are always under pressure relative to no pressure/perfect vacuum, one has to first establish our planet surface pressure, starting at sea level (though down in death valley its higher). Sea Level is 14.696 psia or 1 Atmosphere or 101.3kPa or 29.9 hg or 760 mmhg. That 14.696 psia (that “a†I added is called absolute), and is the starting point of O (zero) psig (“g†for gauge). Why our boost/vacuum gauges have “vacuum†and “boost†is to make it easier to understand the actions going on since when our engine runs in the claimed vacuum it is indeed a lesser pressure (vacuum relative) than atmospheric (14.7 psia) So a NA engine (in the manifold all things flowing proper) will see atmospheric pressure at WOT. Beyond that running a forced induction setup we go past 14.7 psia, but lets switch to a “gauge†reading and call it 0 psig so it makes more sense for everyone/most, so that as we add boost, things will start to look more like what you will see with any normal boost/vacuum gauge you will get. Once in boost and using our boost “gauge†we will max out the 15 psi gauge (assuming a 15 psi max reading for now) at what point the ECM shows as 104 kPa…….someone thinking about this….why 104 kPa when Sea Level is 101.3? Its because the TGP chip table scaling is not written as a 2 bar map scale, does not matter since its only a reference, you can all the scaling Frankenboost for all that matters, its just a reference point to work from when comparing readings to tuning. Here is also a reference from our perfect to use PSIG boost gauges to that odd to use Bar shit the Asian Companies are throwing our way: psig bar 1 = .07 2 = .14 3 = .20 4 = .27 5 = .34 6 = .41 7 = .48 8 = .54 9 = .61 10 = .68 11 = .75 12 = .81 13 = .88 14 = .95 (14.7 = 1.00) 15 = 1.02 Jeff M Quote Link to comment Share on other sites More sharing options...
Jeff M Posted February 23, 2004 Report Share Posted February 23, 2004 or running too much boost for the lower rpms that will put a huge strain on the transmission and are finding some low timing values there once again, to save your ass/tranny. But more on the boost levels to tranny life point, the tranny would like the power to come on gradually, and if boost is ramped within these parameters as they are setup in the TopGun chip then traction is also controlled, which is a win-win scenario for both tranny life and traction that I worked a lot on. So, you're saying that the boost control tables are only there mostly for tranny life?? So, the the boost control tables can be made more aggressive and engine life will not suffer. I've heard others state that too much boost too fast can result in detonation, is this true?? Josh The "settings" in my boost tables are used to control traction and help the tranny last, and get the max boost in the rpm ranges that are safe. Those tables in the chip will do whatever you like, help traction, help tranny life, or not, just ramping the boost up as needed to achieve this. The engine will not care how fast you ramp up the boost and the levels at lower rpms (read surge info in my other post!), long as things are tuned proper for it. Not sure about that statement of too fast of boost detonating, might be something other engines have :? I know a few SyTy guys and T-Type/GNs that get knock right after shift that is still giving them challenges, maybe not anymore as its been a while since I hung with them. Read your post for the 3rd time, maybe I need to say its not how quick the boost comes up that is a engine problem, its just the level you get to when at max. Jeff M Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted February 23, 2004 Author Report Share Posted February 23, 2004 well the trans is out of a 94 bonneville SSEI so I think it is the HD version. the power rating for that engine is 225hp and 275tq so I'm not too worried about it breaking. I wouldn't use the stock turbo above 13psi as it's not worth it. I will be making a better flowing custom setup with a bigger turbo. I just like the idea of being able to control the boost whenever I want. the whole go then let off before tires let loose would be good but the way that turbo spools and the power hits. it's like having a your bestfriends hot GF jump on you once she starts you don't want her to stop even if it's wrong. marcus Quote Link to comment Share on other sites More sharing options...
Jeff M Posted February 23, 2004 Report Share Posted February 23, 2004 Jeff, Lets say I wanted to buy just a normal topgun 160 chip, but with the fuel cut raised about a 1/2 psi, and the timing tables to handle it? Could you do that for me, or would it be too much work? I just don't want to be running into any fuel cut problems like I have with our other TGP. It has the topgun 160, 160 t-stat, k&n filters, removed cat, and different mufflers, and in 20 degree or colder weather it hits the fuel cut. We always run at least 93 octane in it, usually 94 octane, and it pulls HARD until it hits the fuel cut. It has a new stock boost controller, new vacuum lines, and a rebuilt turbo installed all within the last 6 months. So when you say this: Those running into the fuel cut are having some amount of bleeding OR effects from having a bleed/manual control device in line causing their boost to get too high I am not sure it is the truth. I am thinking that when it gets down to 20 degrees, that with the K&N filter, better flowing exhaust, and new turbo that will spool easily, that it is just making that much boost, I am pretty sure it doesn't have any bleeding. Maybe I am wrong, but I think raising the fuel cut .5psi would be nice just to avoid any problems people might be having with this. Thats my opinion on it anyways. Shawn Thanks for clearing me up on this, from the detailed data you provided (mainly turbo rebuilt), I bet that when your turbo was rebuilt that someone got the clocking off a bit. What happens, and a few have had this, is the turbine housing relative to the compressor housing (where the wastegate actuator is mounted!!) is off preloading the spring in the wastegate actuator, causing a higher boost than the ECM can control. I tell people to look at the wastegate actuator rod to see if it is exactly 90 degrees to wastegate actuator itself, this makes sure the ECM can fully control the upper limits of boost, or not which is NOT good if there was a detonation condition that the ECM was working at to also drop your boost (along with knock retard but boost too after about 3 to 4 degrees of sustained knock retard). If you are handy with tools I would take a look at the clocking, if it needs to be changed then pull off the hose on the outlet of the turbo, stick something in the end (hardwood to not gouge the metal inside) and force the compressor housing to turn so the wastegate to rod is at 90 degrees, the housing is only held on with a big C-Clip so the housing will turn without hurting anything! Jeff M Quote Link to comment Share on other sites More sharing options...
Jeff M Posted February 23, 2004 Report Share Posted February 23, 2004 well the trans is out of a 94 bonneville SSEI so I think it is the HD version.the power rating for that engine is 225hp and 275tq so I'm not too worried about it breaking. I wouldn't use the stock turbo above 13psi as it's not worth it. I will be making a better flowing custom setup with a bigger turbo. I just like the idea of being able to control the boost whenever I want. the whole go then let off before tires let loose would be good but the way that turbo spools and the power hits. it's like having a your bestfriends hot GF jump on you once she starts you don't want her to stop even if it's wrong. marcus Just good to make sure its the HD, though one key item to check is the gear and gear carrier set, this is hardened in the TGP and the key element at keeping it from hanging and walking out the side of the tranny case as with the last guy to post pics of his this way. It DOES SOUND as though your tranny is a bit more than the 4T60 that blew its case so you may be ok. As for not being able to just lift the foot off the gas (not all the way off, just back a little like 1/2 to 2/3, need to play with it to find out), think of it this way (seems you are ) when you are getting jiggy with a dream girl, and after a few hours you don't want to spent your rubber quite yet/before her, you slow the boat down some Its about the only time you would like to cross the finish line at the same time Jeff M Quote Link to comment Share on other sites More sharing options...
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