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I'm trying to get some dimensions on a Fast 102mm LSXRT intake. My buddy has a space issue on his LS swap and can't run a car intake as the throttle body sits to low so he has a shitty sheet metal intake that not only is killing power but is also noisy. We're hoping the Fast LSXRT places the t-body high enough that it'll work. Can someone measure from the bottom of the intake to the bottom of the t-body opening? Thanks in advance for any help
Warning... The lsxrt is a pain to tune. Even one of the best tuners, Allen Nelson of Nelson Performance in SA, TX wouldn't charge me after much trying. It would take take 5-6 times to crank start and turn off at every stop sign. Response was great but all else was poor. So after like 6 months, I sold it.
It's hard to get a good reference, but this was taken with the zero-line on the ruler aligned with the bottoms of the flanges that mate to the heads. Even though it doesn't look like it in the pic, because the camera position changed in between aligning the rule and taking the pic.
When this was in my C5, the top of the water pump had to be ground down just a hair to clear the NW 102 throttle body (which was defective and got replaced but that's another long story) so I think the TB location on these is about as low as it could possibly be.
Regarding tuning, it has been a headache to get idle and return-to-idle to work reliably, but in my case there's also cam overlaps and a light-ish clutch (32 pounds) and two different non-stock throttle bodies adding to the challenge. It's pretty good now but it took a lot of trial and error. But I'm tuning it myself and I would expect an experienced tuner get get it done much faster. I had a LOT to learn about all of the quirks of idle in Gen-III PCMs.
Warning... The lsxrt is a pain to tune. Even one of the best tuners, Allen Nelson of Nelson Performance in SA, TX wouldn't charge me after much trying. It would take take 5-6 times to crank start and turn off at every stop sign. Response was great but all else was poor. So after like 6 months, I sold it.
I hope you are not talking about the same Nelson that was in SA about 20 years ago. If so, his "tuning" was what made me learn to tune for myself.