Ok im buying a gt28rs
#121
10-26-2007, 01:32 PM
RE: Ok im buying a gt28rs
ORIGINAL: sean1.8t
am i reading that right???? [sm=insomnia.gif]
ORIGINAL: cincyTT
good point Sean.
good point Sean.
#122
10-26-2007, 02:01 PM
RE: Ok im buying a gt28rs
ORIGINAL: Bogie
Cincy/Sean/Chaos- need some advice,
I know that the HP and TQ curves always cross at 5,252 rpms. TQ > HP below 5,252 rpms, and HP > TQ above 5,252 rpms. But isn't it really a combination of the tq and hp that break or bend the rods at high rpms? it really depends on how the tq comes into play. If you ever look at a journal bearing vs a ball bearing dyno, you can see why a t3t4 will make more power on stock rods due to the lower tq it produces and the more gentle increase in power compared to a more rapid increase in power and higher tq #'s from a gt turbo. Its mainly the amount and how the tq occures that breaks rods. Thats why you can make more hp with a gt2871r .86 and t3t4 50trim than a gt2871r .64 before the rods will give.The .86 and 50trim have a little more lag and smoother tq curve than the faster spooling .64. Thats why saying certain hp/tq #'s will snap rods isnt the same turbo to turbo. its basically a rule of thumb to get new rods when you pass 300whp and are looking for more.
All i know or think i know about aftermarket turbos is what has been postedhere in the last couple of weeks.
I'm stillnot sure on the differences between the gt3071r or gt3076r?or the gt28rs vs the gt2871r that chaos will most likely buy.
Each family of turbo (gt25, gt28, gt30 etc) will all have the same turbine wheels and housings. The last 2 #'s are for the inducer and exducer. Since they are usually the next step up, you wont find a big differnce in spool between turbos in the same family ( gt28rs vs gt2871r) vs a gt3071r and a gt2871r with a slightly larger differnce. Go to turbobygarrett.com and read turbo tech 101-103 for more info
Ialso think i understand that there are differentsizes within thecases ex..63 or .64 or .86. where the lower #s like .63 spool faster and create more low end torque than the 0.86. but the 0.86 has more flow and less lowend tq. thisreminds me ofhow an exhaustpipe withtoo big a diameter will cause an engine to lose torque (but allow for more flow and hp).
Those are the turbing a/r's. The t25 housings come in .64 .86 and the t3 housings come in .48 .63 & .82 (both have bigger but not worth mentioning since 99.999999999999999% of the people here wont ever use one and other less used varients) Even with the simular #'s they are not the same. The .48 is slightly smaller than the .64. The .63 is between the .64 and .86 but closer to the .64. The .86 is next followed by the .82 being the largest. Now these numbers play a huge part in what turbo you buy. They will increase spool or add lag and increase topend. But on a larger turbo where you think you can run a smaller housing to increase spool, you may actually choke the turbo due to lack of flow. Also t3's will flow more and should be used with turbos in the gt30 family but still worth the extra few $$ on a gt2871r and more so if you ever think about upgrading.
anywaywhat is the best setup to get for:
1.a dd commuter(mostly highway) - must be reliable, but i want this car to go fast and have good pickup. depends on what total power you want and when you want it, not to mention cost. A faster spooling turbo with good midrange or a larger turbo with a decent mid and great topend. The gt28rs, gt2871r, t3 60trim and t3t4 50trim .48 are all very popular DD setups.
2. how much hp/tq or what are limits you wouldSAFELY push a stock 1.8t with 155k well maintained (ie- synthetic oil changes regularly)and
whatsetup will get meto the point just beforemy new 2.25" Borlacat-backexhaustwill bea bottleneck? -at the time i didn't wantto splurge for the 3" APR cat back...
I would do a compression test before doing anything to that engine. If all checks out, your good to go. If not, a new set of rings and rehoned would help get back the stock compression. The exhaust is going to need to be 2.5-3".
3. Not sure i want to get into changing the clutch right away, but recent posts suggest it's a must. it is what it is. Lower boost can always be used to prolong the life of the clutch if needed. Instead of running 20-22psi, run 15psi
4. I see no point in buying the chipor software until i have the injectors and turbo to put it to use. uless it is simple to upgrade software to the chip and i can do it at home. if you get a revo stock chip, they will only charge you a little more for an upgrade, same with other tuners. But make sure they have stock and a BT file for you before commiting to anything
and is there a site that has all these turbos specs and costs side by side for comparisions and compatabilities with ecu chips or software?
Thanks. atpturbo.com, pagparts.com, and turbobygarrett.com
Another thing- what is the highest recommended boost level for driving with 91 or 93 octane? depends on the turbo, most is 20-24psi
Cincy/Sean/Chaos- need some advice,
I know that the HP and TQ curves always cross at 5,252 rpms. TQ > HP below 5,252 rpms, and HP > TQ above 5,252 rpms. But isn't it really a combination of the tq and hp that break or bend the rods at high rpms? it really depends on how the tq comes into play. If you ever look at a journal bearing vs a ball bearing dyno, you can see why a t3t4 will make more power on stock rods due to the lower tq it produces and the more gentle increase in power compared to a more rapid increase in power and higher tq #'s from a gt turbo. Its mainly the amount and how the tq occures that breaks rods. Thats why you can make more hp with a gt2871r .86 and t3t4 50trim than a gt2871r .64 before the rods will give.The .86 and 50trim have a little more lag and smoother tq curve than the faster spooling .64. Thats why saying certain hp/tq #'s will snap rods isnt the same turbo to turbo. its basically a rule of thumb to get new rods when you pass 300whp and are looking for more.
All i know or think i know about aftermarket turbos is what has been postedhere in the last couple of weeks.
I'm stillnot sure on the differences between the gt3071r or gt3076r?or the gt28rs vs the gt2871r that chaos will most likely buy.
Each family of turbo (gt25, gt28, gt30 etc) will all have the same turbine wheels and housings. The last 2 #'s are for the inducer and exducer. Since they are usually the next step up, you wont find a big differnce in spool between turbos in the same family ( gt28rs vs gt2871r) vs a gt3071r and a gt2871r with a slightly larger differnce. Go to turbobygarrett.com and read turbo tech 101-103 for more info
Ialso think i understand that there are differentsizes within thecases ex..63 or .64 or .86. where the lower #s like .63 spool faster and create more low end torque than the 0.86. but the 0.86 has more flow and less lowend tq. thisreminds me ofhow an exhaustpipe withtoo big a diameter will cause an engine to lose torque (but allow for more flow and hp).
Those are the turbing a/r's. The t25 housings come in .64 .86 and the t3 housings come in .48 .63 & .82 (both have bigger but not worth mentioning since 99.999999999999999% of the people here wont ever use one and other less used varients) Even with the simular #'s they are not the same. The .48 is slightly smaller than the .64. The .63 is between the .64 and .86 but closer to the .64. The .86 is next followed by the .82 being the largest. Now these numbers play a huge part in what turbo you buy. They will increase spool or add lag and increase topend. But on a larger turbo where you think you can run a smaller housing to increase spool, you may actually choke the turbo due to lack of flow. Also t3's will flow more and should be used with turbos in the gt30 family but still worth the extra few $$ on a gt2871r and more so if you ever think about upgrading.
anywaywhat is the best setup to get for:
1.a dd commuter(mostly highway) - must be reliable, but i want this car to go fast and have good pickup. depends on what total power you want and when you want it, not to mention cost. A faster spooling turbo with good midrange or a larger turbo with a decent mid and great topend. The gt28rs, gt2871r, t3 60trim and t3t4 50trim .48 are all very popular DD setups.
2. how much hp/tq or what are limits you wouldSAFELY push a stock 1.8t with 155k well maintained (ie- synthetic oil changes regularly)and
whatsetup will get meto the point just beforemy new 2.25" Borlacat-backexhaustwill bea bottleneck? -at the time i didn't wantto splurge for the 3" APR cat back...
I would do a compression test before doing anything to that engine. If all checks out, your good to go. If not, a new set of rings and rehoned would help get back the stock compression. The exhaust is going to need to be 2.5-3".
3. Not sure i want to get into changing the clutch right away, but recent posts suggest it's a must. it is what it is. Lower boost can always be used to prolong the life of the clutch if needed. Instead of running 20-22psi, run 15psi
4. I see no point in buying the chipor software until i have the injectors and turbo to put it to use. uless it is simple to upgrade software to the chip and i can do it at home. if you get a revo stock chip, they will only charge you a little more for an upgrade, same with other tuners. But make sure they have stock and a BT file for you before commiting to anything
and is there a site that has all these turbos specs and costs side by side for comparisions and compatabilities with ecu chips or software?
Thanks. atpturbo.com, pagparts.com, and turbobygarrett.com
Another thing- what is the highest recommended boost level for driving with 91 or 93 octane? depends on the turbo, most is 20-24psi
#123
10-27-2007, 08:27 PM
RE: Ok im buying a gt28rs
ORIGINAL: cincyTT
why is that so hard to believe? You and i both know that point and i think < 10% others here do also.
why is that so hard to believe? You and i both know that point and i think < 10% others here do also.
but i have no idea you are trying to say with that last part [sm=wtf.gif]
#124
10-27-2007, 08:30 PM
RE: Ok im buying a gt28rs
ORIGINAL: Kyle09
Hows it sounds...you got some vids?
Hows it sounds...you got some vids?
and no sound clips unfortunately. i don't have the program for my camera to transfer vids to the computer
#125
10-27-2007, 08:44 PM
RE: Ok im buying a gt28rs
ORIGINAL: sean1.8t
oh i don't know. because it seems that whatever i say. no matter if it's right or not, you seem to make it a personal mission to prove me wrong. not that i don't mind it. whatever gets you your 1000 posts per day i guess...
but i have no idea you are trying to say with that last part [sm=wtf.gif]
ORIGINAL: cincyTT
why is that so hard to believe? You and i both know that point and i think < 10% others here do also.
why is that so hard to believe? You and i both know that point and i think < 10% others here do also.
but i have no idea you are trying to say with that last part [sm=wtf.gif]
And the last part was about people not getting if you upgrade one part, you need to upgrade other parts.
#126
10-27-2007, 10:01 PM
RE: Ok im buying a gt28rs
not post whoring? 8000+ posts in less than 11 months, and on this forum alone.. come on 
but ah yes, most people do not understand that part.. like kyle, have you given any thought to suspension or brakes?
but ah yes, most people do not understand that part.. like kyle, have you given any thought to suspension or brakes?
#127
10-27-2007, 10:19 PM
RE: Ok im buying a gt28rs
ORIGINAL: sean1.8t
not post whoring? 8000+ posts in less than 11 months, and on this forum alone.. come on
not post whoring? 8000+ posts in less than 11 months, and on this forum alone.. come on
#130
10-28-2007, 10:38 AM
RE: Ok im buying a gt28rs
Thats ok. Knowledgable posts arent typically generated from playing Halo 3 all day everyday! [8D]