90mm TB: TPIS vs other custom
Le Mans Master
Joined: Nov 2000
Posts: 7,294
Likes: 1
From: Coral Springs Florida
Re: 90mm TB: TPIS vs other custom (Phil97SVT)
Good post Phil..I'm anxious to hear the feedback on this question..
From what I have been hearing and reading here on the forum..It appears that are very few tuners ...if any..that can tune the 90mm TB and intake. There is is just soooo much new air now coming and it's playing havoc with the PCM values set by the tuners. It's been especially harder on the M6's ..the Automatics like mine are doing a little better with the daily drive.
Obviously we are trading off for that WOT power through the upper rpm range at the track, but for a every day driver it's been a concern for many of our M6 members.
I can tell you from personal experience that my TPIS oval TB and modified LS6 intake was NOT easy to tune for Mike Norris. It still wants to race up in the 2000 rpms range on a cold start and takes a while to come down to the idle set at 975 rpms. Regardless, the new air introduced by these big mouth TB's are really something that hasn't been worked out yet IMO and I for one will continue to listen and learn from the tuners that KNOW how to properly tune a vehicle with these new TB's..Good Luck Phil
From what I have been hearing and reading here on the forum..It appears that are very few tuners ...if any..that can tune the 90mm TB and intake. There is is just soooo much new air now coming and it's playing havoc with the PCM values set by the tuners. It's been especially harder on the M6's ..the Automatics like mine are doing a little better with the daily drive.
Obviously we are trading off for that WOT power through the upper rpm range at the track, but for a every day driver it's been a concern for many of our M6 members.
I can tell you from personal experience that my TPIS oval TB and modified LS6 intake was NOT easy to tune for Mike Norris. It still wants to race up in the 2000 rpms range on a cold start and takes a while to come down to the idle set at 975 rpms. Regardless, the new air introduced by these big mouth TB's are really something that hasn't been worked out yet IMO and I for one will continue to listen and learn from the tuners that KNOW how to properly tune a vehicle with these new TB's..Good Luck Phil
Le Mans Master
Joined: Oct 2002
Posts: 6,799
Likes: 11
From: dudley MA
Re: 90mm TB: TPIS vs other custom (J-Rod)
from what ive read on other forums the tpis 90mm TB has spring problems. there not closing the door all the way causing idle problems. i went with the lg 90mm TB for that reason.
Safety Car
Joined: Mar 2002
Posts: 4,928
Likes: 1
Cruise-In V Veteran
St. Jude Donor '09
Re: 90mm TB: TPIS vs other custom (Phil97SVT)
What are the differences in the throttlebodies on the market? Anyone better than the others?
The finest 90 mm TB available is Nick William's ...hands down - which I believe LGM has one version. Nick and gojo have spent alot of time, and effort, developing and testing Nick's 90mm TB. It's a work of art....esthetically and functionally.
gojo has been able to tune his to flawless perfection
Not too shabby as he has an A4. gojo is one heck of a tuner! [Modified by Bink, 11:20 PM 6/30/2004]
Melting Slicks
Joined: Oct 2002
Posts: 2,855
Likes: 0
Re: 90mm TB: TPIS vs other custom (Phil97SVT)
I have both and they are beautiful pieces and you don't realize how big they are until you put them next to a stocker--I am putting Nick's on this weekend to compare again for drivability, whether one puts out more power I don't know it would be interesting to test both, however I think it would be too close to call, I will go with the one that will idle and Nick seems to have spent a lot of time working on his while TPIS sold theirs and have done no follow up to help make their product work--several of the tuners seem to have it down, I know Carmen (VDs) Julio (Cartek) and Jason and Dave at MTI seem to have been successful with the strokers, its coming around just a learning curve it will be commonplace soon enough I guess--getting power out of it is not a problem and boy is it there, but low rpm operation is diff---rj383 has the tune down as well and Speedog emailed back and forth on his stroker for 2 months and has his running like stock, I also understand Charley at LAPD has a setup on his stroker and it runs like stock, so it can be done, I think more people have been successful with it on the 346 motors than the strokers--
Melting Slicks
Joined: Dec 2000
Posts: 2,204
Likes: 5
From: Bethlehem PA
St. Jude Donor '03-'05-'06-'08-'10
Re: 90mm TB: TPIS vs other custom (NEPTUNEBILL)
I have the TPIS 90 mm TB and modified manifold installed and tuned by Carmen at the Vette Doctors and the combo works just fine in daily driving. Yes, there is a slight rise in RPM (1200RPM) at initial start after which it settles down to the normal idle RPM. SOTP on the street feels real good, haven't had it to the track as yet.
Joe
Joe
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Drifting
Joined: Feb 2003
Posts: 1,453
Likes: 1
From: Iowa City, IA
Re: 90mm TB: TPIS vs other custom (NEPTUNEBILL)
I hear that the FAST 90mm intake and 90mm TB are a F*** B*** to tune and after 1000-3000 miles they have to reset the motor to get it out of limp mod.
Le Mans Master
Joined: Jul 2002
Posts: 6,147
Likes: 32
From: Dallas TX
Re: 90mm TB: TPIS vs other custom (extremecorvette)
weird
my tuner has only tuned one 90mm FAST/TPIS combo and last I heard the car was not having any problems. He said it didnt take him much longer than a normal tune. I will ask for an update to see how that car is doing.
my tuner has only tuned one 90mm FAST/TPIS combo and last I heard the car was not having any problems. He said it didnt take him much longer than a normal tune. I will ask for an update to see how that car is doing.
Le Mans Master
Joined: Jul 2002
Posts: 6,147
Likes: 32
From: Dallas TX
Re: 90mm TB: TPIS vs other custom (extremecorvette)
maybe by problems they mean that once ever 2-3 hours, the idle goes up to 2000rpm for a couple seconds
It probably isnt perfect but with all the crap in my car, I dont really notice little things like that.
I know that guy that had his tuned for 2 hours has never brought it back for a retune but his car is just a weekend driver.
It probably isnt perfect but with all the crap in my car, I dont really notice little things like that.
I know that guy that had his tuned for 2 hours has never brought it back for a retune but his car is just a weekend driver.
Melting Slicks
Joined: Feb 2002
Posts: 2,613
Likes: 0
From: Winston Salem NC
Re: 90mm TB: TPIS vs other custom (extremecorvette)
Nate,
Tell "they" to raise the values in the calculated airflow table and it will stop setting P1514 and stop going into limp. The greater airflow exceeds the test values.
[Modified by gojo, 6:51 PM 7/1/2004]
Tell "they" to raise the values in the calculated airflow table and it will stop setting P1514 and stop going into limp. The greater airflow exceeds the test values.
[Modified by gojo, 6:51 PM 7/1/2004]
Racer
Joined: Sep 2000
Posts: 487
Likes: 0
From: Below the Mason/Dixon Line Alabama
Re: 90mm TB: TPIS vs other custom (NEPTUNEBILL)
Hey Bill; thanks for the mention.
As I understand things, the stock displacement engines are easier to tune than our larger ones. The increase in total airflow, as well as the cams, intakes and so forth, simply make it a bit more difficult.
As has been pointed out increasing the predicted airflow table seems to fix the reduced power output stuff (though perhaps not for all) but of course doesn't solve idle issues. RJ has gotten mine good enough so I don't fear driving in traffic but I suspect there's no way to make these radical setups entirely well behaved at minimal throttle settings. It's very much like the days of high compression engines, with wild cams and big carbs: they sure liked to run but weren't entirely happy in parking lots. With what we've done to these cars (including making it up as we go along) I'm not surprised we can't get these things entirely right.
As I understand things, the stock displacement engines are easier to tune than our larger ones. The increase in total airflow, as well as the cams, intakes and so forth, simply make it a bit more difficult.
As has been pointed out increasing the predicted airflow table seems to fix the reduced power output stuff (though perhaps not for all) but of course doesn't solve idle issues. RJ has gotten mine good enough so I don't fear driving in traffic but I suspect there's no way to make these radical setups entirely well behaved at minimal throttle settings. It's very much like the days of high compression engines, with wild cams and big carbs: they sure liked to run but weren't entirely happy in parking lots. With what we've done to these cars (including making it up as we go along) I'm not surprised we can't get these things entirely right.
Melting Slicks
Joined: Oct 2002
Posts: 2,855
Likes: 0
Re: 90mm TB: TPIS vs other custom (SPEED DOG)
Well Eric yours sounds like a pleasure--mine below 2K is really bad depending on what day it is--the idle has a mind of its own and using the AC is likely out of the question I am afraid to try it again---2K jump on cold start doesn't bother me, if I let it idle and warm up it runs pretty well for a while, then it will decide its tired or something and makes life a nightmare--the saving grace is we know it can be done and will be eventually---if I build a GTO I will use the same setup so I hope to conquer the problems now so the 427 in the goat will not have the probs I've gone through with this project--including oil consumption that I think will back off with the breathers I am installing--