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Seems like there are WAY more options on a 102 Throttle Body than I thought there would be. I need one for a Fast LSXR 102, what are the top players that people aren't having a problem with?
Seems like there are WAY more options on a 102 Throttle Body than I thought there would be. I need one for a Fast LSXR 102, what are the top players that people aren't having a problem with?
The large 102mm and up TBs don't play well with C5 Corvette electronics. Very difficult to get them tuned satisfactorily. Not my opinion. This info came straight from Nick Williams himself. I was wanting to put one on the built LS7 in my 2000 C5. He didn't want to sell me one. Since part of his business is selling them, I figure he must know there are problems, or he would've sold me one. IDK if this is true with all Gen 3 electronics, or not. FWIW
I ran a 90mm gold blade throttle body on my 102 intake for over 2 years on track. No issues whatsoever.
Since the gold blade has a finer resolution, it opens farther than 100%, according to the PCM. So my tuner had to set the throttle opening to like 90% to keep it from going into reduced engine power mode. It still opens fully, as the blade isnt closed more the cross section of the shaft its mounted on, but the PCM is happier. I wonder if that is similar to the issues people see with the 102+ sizes. I am putting a Summit 102mm on my LS3 build so we'll see when dyno day comes if my tuner has issues.
Seems like there are WAY more options on a 102 Throttle Body than I thought there would be. I need one for a Fast LSXR 102, what are the top players that people aren't having a problem with?
for DBW, NIck Williams or Katech. Katech basically copied NW and builds them same with GM electronics. EVERYTHING else is China crap and has a totally different motor style used because it's cheaper. I've owned a lot of them, so I've seen the variations. You can put a stock 90mm on the FAST intake, but why? If you are going big, go all the way. That being said, unless you are making over 600fwhp the bigger TB won't make any difference, so that is a factor too. If you decide to go stock route, I have a GM silver blade and a gold blade 90mm for sale.
I run a NW 102 I believe I bought from DualQuadDave. This is on a stroker LS2 with a ported Fast 102 intake. GenIII/genIV e40 ecm and I have zero problems. Also running a light RPS BC2 carbon clutch with zero issue. Your tuner is your friend, hopefully. Don't skimp on the tune.
For anyone thats curious, the 102mm I had for my C5 didnt work at first. I tried both a Summit brand and a Trick Flow that had different internals. Same story. The C5 is incredibly picky on TPS voltage, but these werent even communicating with the pedal and going into REP.
I ended up having to switch the +5v reference and ground pins on the adapter harness for the TB to work.
On the dyno, the 102mm was worth +8hp over the stock LS3 90mm.
The large 102mm and up TBs don't play well with C5 Corvette electronics. Very difficult to get them tuned satisfactorily. Not my opinion. This info came straight from Nick Williams himself. I was wanting to put one on the built LS7 in my 2000 C5. He didn't want to sell me one. Since part of his business is selling them, I figure he must know there are problems, or he would've sold me one. IDK if this is true with all Gen 3 electronics, or not. FWIW
I think it's a mistake to blame the C5 electronics for this - the C5 electronics work just fine with three kinds of GM's throttle bodies. The real problem here is that NW can't get the 0-5v signal from their blade angle sensors to match the signal from the GM throttle bodies.
With the C6 and later, you can adjust the way that the PCM interprets the signals from the position sensors, so you can tune around the throttle body quirks with those PCMs. But if the throttle bodies were compatible, that wouldn't even be necessary.
And there's a mechanical aspect to it as well. The GM throttle bodies start flowing air when the blade moves just a tiny bit. I have a Katech 103mm (which I'm told is a rebranded NW) and it doesn't even start to flow any air at all until the blade has moved a LOT further. So at cold starts, the NW throttle body is just barely flowing enough air for my car to idle while it's telling the TAC that throttle blade is 18% open... And 18% is all the TAC will allow at idle. So cold starts are crap, especially in the winter.
I just got a widget from Torque Rush that will let me re-map the throttle blade angle sensor signal and I'm gonna play with that over the summer, I'm pretty sure it will fix my cold-start issues - and also the fact that the "reduced engine power" mode (where the TAC limits the blade angle to 25%) barely allows enough air for the car to move forward on level ground. I had to get towed off of a track last year because I couldn't make it back to the pits in REP mode.
I think it's a mistake to blame the C5 electronics for this - the C5 electronics work just fine with three kinds of GM's throttle bodies. The real problem here is that NW can't get the 0-5v signal from their blade angle sensors to match the signal from the GM throttle bodies.
With the C6 and later, you can adjust the way that the PCM interprets the signals from the position sensors, so you can tune around the throttle body quirks with those PCMs. But if the throttle bodies were compatible, that wouldn't even be necessary.
And there's a mechanical aspect to it as well. The GM throttle bodies start flowing air when the blade moves just a tiny bit. I have a Katech 103mm (which I'm told is a rebranded NW) and it doesn't even start to flow any air at all until the blade has moved a LOT further. So at cold starts, the NW throttle body is just barely flowing enough air for my car to idle while it's telling the TAC that throttle blade is 18% open... And 18% is all the TAC will allow at idle. So cold starts are crap, especially in the winter.
I just got a widget from Torque Rush that will let me re-map the throttle blade angle sensor signal and I'm gonna play with that over the summer, I'm pretty sure it will fix my cold-start issues - and also the fact that the "reduced engine power" mode (where the TAC limits the blade angle to 25%) barely allows enough air for the car to move forward on level ground. I had to get towed off of a track last year because I couldn't make it back to the pits in REP mode.
Although it shouldn't be needed, it seems that drilling a small hole in your TB blade could alleviate some of the cold start issue. You would just have to make sure it isn't a big enough hole to cause hot idle issues. Of course then you would have to remap a few tables to match.
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Electronic 102mm TB? 
