#10773, "loosing power when i shift" May-24-04 07:19 AM by chrysler kid
i need help to diagnose this or you to tell me its normal. whenever im playing around with my friends on the highway i can stay even with them from a punch but when i have to shift my car looses all power and they just blow past me. from a 40 punch i keep it in 3rd and i stay even with my friend in his wrx then i shift to 4th and its like my car wont make power. it feels the same to me but im obviously loosing too much power. im thinking that it could be the t25 having issues or the worse is that my car has some crankwalk and when i shift im loosing power etc
any ideas?
i ran a 14.5 at 95 mph when i went to the track recently so mayybe my car just doesnt like the highway??
#10777, "RE: loosing power when i shift" In response to Reply # 2
Originally posted by BigBald yep it is normal...t25 has no top end...Get a ball bearing turbo and you should have no problem....you loose almost no power with those things.....
Ball bearing actually has more to do with how fast a turbo spools, not with how much top end it has.
The size of the turbo (compressor wheel, housing and turbine housing) has to do with how long it makes power.
#10778, "RE: loosing power when i shift" In response to Reply # 4
Originally posted by HybriDSM
Originally posted by BigBald yep it is normal...t25 has no top end...Get a ball bearing turbo and you should have no problem....you loose almost no power with those things.....
Ball bearing actually has more to do with how fast a turbo spools, not with how much top end it has. The size of the turbo (compressor wheel, housing and turbine housing) has to do with how long it makes power.
#10782, "RE: loosing power when i shift" In response to Reply # 4
Originally posted by HybriDSM
Originally posted by BigBald yep it is normal...t25 has no top end...Get a ball bearing turbo and you should have no problem....you loose almost no power with those things.....
Ball bearing actually has more to do with how fast a turbo spools, not with how much top end it has. The size of the turbo (compressor wheel, housing and turbine housing) has to do with how long it makes power.
not true....in fact a very common mis-conception. Ball Bearing has nothing to do with how fast the turbo spools and everything to do with holding boost while shifting. It appears he is loosing power between shifts, ball bearing will minimize that power loss. BB turbos have documented spool times the same as normal turbos. IF this info is incorrect please point me in the direction where yours came from.
The issue cam up because some was complaining about the spool time of the FP3052 being identical to that of the 16g. They thought that have a BB turbo would make it spool as fast as the t25. IT was then brought up by one of the wisemen that BAll Bearing has nothing to do with spool time and everything to do with holding power between shifts which is a huge issue for manuals. Now noone ever refuted this claim and actually a few others agreed. So I am interested in how this is not true suddenly.
_____________________________________________ Jerrome B. 1995 GSX - Race 1997 GST - Drive 1995 GST - Who the hell knows
#10783, "RE: loosing power when i shift" In response to Reply # 9
Originally posted by BigBald
Originally posted by HybriDSM
Originally posted by BigBald yep it is normal...t25 has no top end...Get a ball bearing turbo and you should have no problem....you loose almost no power with those things.....
Ball bearing actually has more to do with how fast a turbo spools, not with how much top end it has. The size of the turbo (compressor wheel, housing and turbine housing) has to do with how long it makes power.
not true....in fact a very common mis-conception. Ball Bearing has nothing to do with how fast the turbo spools and everything to do with holding boost while shifting. It appears he is loosing power between shifts, ball bearing will minimize that power loss. BB turbos have documented spool times the same as normal turbos. IF this info is incorrect please point me in the direction where yours came from. The issue cam up because some was complaining about the spool time of the FP3052 being identical to that of the 16g. They thought that have a BB turbo would make it spool as fast as the t25. IT was then brought up by one of the wisemen that BAll Bearing has nothing to do with spool time and everything to do with holding power between shifts which is a huge issue for manuals. Now noone ever refuted this claim and actually a few others agreed. So I am interested in how this is not true suddenly.
I think you are arguing my side of the point. Losing power between shifts and spool time are intrinsically linked. A ball bearing turbo spools considerably faster than a conventional bearing turbo. This free spooling ability also allows the turbo to spin freely between shifts, thus making power and boost loss between shifts a greatly diminished problem. The original comment was this; that ball breaing does not have anything to do with top end or the ultimate flow characteristics of a turbo and how much power it makes.
All things being equal, two identical turbos, one ball bearing the other conventional bearing, the one with ball bearing will hit full boost first and will also lose less boost between shifts. Those two concepts are the same. Less friction means less power loss.
The reason I say this is I have practical experince with it. I ran a ball bearing 60-1 for a while last summer and even with a malfunctioning fuel pump and a disastrously tuned car, I was hitting 20+ PSI by 3100 RPM. On the conventional bearing 14b, those numbers were about equal. Also, after talking through my turbo with the fine gentlemen at AGP before I bought mine, they explained in detail how ball bearing turbos decrease spool time by 25% or more.
The original point of my comment quoted above stands, that ball bearing has nothing to do with power, in terms of how much a turbo flows, but is able to "create" more power by speeding up boost and letting be maintained more efficiently between shifts.
#10784, "RE: loosing power when i shift" In response to Reply # 10
Matt's 60-1 Ball Bearing turbo hit full boost almost 1000rpm earlier than my Green. His turbo is substantially larger than my turbo, yet it spools about 25% faster. I guess ball bearings have nothing to do with that...
I always take personal experience over something I read on the internet. I personally installed a ball bearing turbo and drove the car afterward. It absolutely 100% spools faster than a conventional bearing turbo.
The reason a ball bearing turbo keeps spooling between shifts is the reduction in friction at the bearing. The speed at which the turbo spools depends on a number of things. One being size, one being materials, and one being the amount of friction at the bearing, among other things. Think about it. It is all physics.
#10785, "RE: loosing power when i shift" In response to Reply # 11
I can see the between shifts but i can't see the quicker spool because of this. What about those who also have the BB turbo and complain about spool time. I see what both of you are saying, but the post i read were also from alleged experience.
Since you two dealt with them, do you recommend them? I heard that 1. there is no rebuild for these things and 2. they are high maintenance meaning an small filter needs to be attached to a feed line and changed every oil change and 3. they only last about 12k....is any of the following true?
_____________________________________________ Jerrome B. 1995 GSX - Race 1997 GST - Drive 1995 GST - Who the hell knows
#10786, "RE: loosing power when i shift" In response to Reply # 12
The turbo MUST be supplied by a constant CLEAN source of oil to keep the ball bearing cartridge lubricated. Most turbos come with an in line filter kit that you use. They will last forever as long as you turbo time them appropriately (I.E. 3-5 mintues). The death of these turbos is from idiots not turbo timing them or not keep them with a clean supply of oil which clogs the ball bearing cartridge and causes it to seize and fail.
As for how it spools faster, it is identical in theory to how it keeps up speed in between shifts. There is virtually no friction in the cartirdge where the shaft spins. No friction means it takes very very little for the turbo to spool. I recommend a BB turbo highly as long as you are willing to turbo time the bag out of it and change the inline filter often. Like anything, you get out of it what you put in. Neglect it and it will fuck you.
#10787, "RE: loosing power when i shift" In response to Reply # 13
Actually i can now see what you are talking about. IT is a toss up between FP3052 and FP Green which are virtually the same turbo but one is ball bearing. Why did you and Jeff switch up from BB?
_____________________________________________ Jerrome B. 1995 GSX - Race 1997 GST - Drive 1995 GST - Who the hell knows
#10788, "RE: loosing power when i shift" In response to Reply # 14
Originally posted by BigBald Actually i can now see what you are talking about. IT is a toss up between FP3052 and FP Green which are virtually the same turbo but one is ball bearing. Why did you and Jeff switch up from BB?
Jeff has a Green (conventional bearing). I have still have a ball bearing 60-1 (my earlier terminology suggested I got rid of it, but the car has been down since the summer so I speak about it in the past tense.)
#10789, "RE: loosing power when i shift" In response to Reply # 15
if your doing a 4th gear pull you should kill a WRX on the highway. all-wheel drive takes more power to keep it going at highway speeds. in my experience the t-25 will lose it's power around mid-5K rpm's in 4th. upgrade the turbo, an evo16G will provide more than enough power for street driving. i daily drive at 19p.s.i. and get full boost at 3100 rpm with the evo16G. only drawback is boost creep, which means porting the HELL out of your turbo amongst other things. the t-25 is a joke because it is too damn small. upgrade the turbo and you will have more fun. good luck -Scott
1995 GST 6-bolt JDM swap Evo 16G port/polish 28x7.5x3.5 FMIC (had to cut bumper to make it fit) 686 Injectors Walbro 255-HP ACT 2600 Clutch Full 3" Turbo-Back Exhaust RamCharge MAF Translator w/ upgrade chip RRE Front/Rear Strut Bar Eibach Pro-Kit NGK Plugs/Wires Crushed 1g BOV vented to atmosphere Apexi SAFC Powerslot Rotors Autometer Phantom A/F, Boost, EGT Redline Synthetic M.T.F. 2g Manifold ported w/ ported 02 housing K&N Custom Cold Air Intake Apexi Turbo Timer Joe P MBC @ 19p.s.i.
