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replacing TB

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Old 04-11-2018 | 06:08 AM
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Hoping to get a little help here. I have a 97 Corvette with 243 Heads an LS6 intake, with FAST 30# injectors and a SLP Blackwing CAI, I have an LS6 TB that I would like to put on. It is from a 2004 Corvette. I know that the 97's have a limitation of 11,250 Hz, and the 04 TB is from a Vette with the 12,000 Hz. I have HP tuners is there any way to calibrate this TB to use on my car. Any help would be appreciated.
Thanks in advance Harold
Old 04-11-2018 | 06:59 AM
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The throttle body doesn't have to be calibrated in Hz, that's the MAF.
Old 04-11-2018 | 07:07 AM
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So I can just install the lager TB without a problem, I also have the larger MAF from the same 04 Vette. I am also going from a 3 wire MAF with a seperate IAT to a 5 wire MAF, I have bought the conversion cable from Pace performance.
Thanks
Harold

Last edited by 97Fun; 04-11-2018 at 07:12 AM. Reason: adding information
Old 04-11-2018 | 07:14 AM
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I'm not entirely certain that there was any noticeable difference in TB size between the 3 bolt ones. I thought they were all either 75 or 78mm, certainly not enough of a difference to change anything.
Old 04-11-2018 | 07:30 AM
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Default Repalcing TB

Yes it is a 78mm but it is a descreened TB from a Z06. I'm a little uncertain how to handle the difference in the MAF with my old one being a 11,250 Hz and the new one a 12,000 Hz. The limitations of my ECM are 11,250 Hz Any help on how to handle this without replacing the ECM would be greatly appreciated.

Thanks again
Harold

Last edited by 97Fun; 04-11-2018 at 07:32 AM. Reason: adding information
Old 04-11-2018 | 08:31 AM
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Throttle bodies were never screened. That's still MAF you're talking.

Also, your ECM limit are just that, limits. Unless you plan on making 600 horsepower, you wont be near the limit of your MAF.
Old 04-11-2018 | 09:01 AM
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Default ReplacingTB

Sorry, you are correct I was talking about when I replace the MAF it seems as though there are issues with changing it out to a 2001 and up MAF. I copied this from the LS1 how to,

If you have a 97-98 year car, that leaves you with the 11,250-12,000 range that will be unconvertible since no entries can exist for that range. What this means is with the new maf table, once you hit the 11,250hz your maf will flatline. Now, you may say that your car ran fine before with that limit so it also will with the new maf, but that is not the case. Read on...

The 97-2000 maf says that 11,250hz is 428.52 gms/sec of airflow. Well, the new 2001+ maf will say that 11,250hz is 359.16, which means that on a 97 or 98 year model car, your maximum measured airflow will drop by over 68gms/sec (from 428 to 359). This is why for '97 and '98 year models you should buy the recalibrated maf, or do not do this mod at all! 1999 and 2000 model cars will have the extended maf table up to 12,000hz and their ceiling will remain within the same threshold as it was stock, which is what we want.
Hopefully this will let you see what I am concerned with on upgrading my MAF, or can I just rescale my MAF in HP tuners.

Thanks
Harold


Old 04-11-2018 | 02:12 PM
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I've always just rescaled the MAF in HPtuners when changing the MAF. There is a table in most of the PCMs for frequency vs airflow. I think that change was referring to direct swaps, as in swapping to a higher flow MAF as a bolt-on upgrade.

I guess it would depend on the min/max ranges for that specific table on your PCM.
Old 04-16-2018 | 07:15 AM
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Can I just rescale it to the 428.29 at 11,2500. Can it be that easy?
Thanks Harold




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