Random84

Any of you have experience swapping out your 102mm throttle body for a larger unit, such as the 112 from NW/Kong?

I have a 400" with AllPro heads, appropriately sized cam with a Kong2650 and Flex fuel. The last dyno I did wasn't a clean pull (some knock retard) but it was 840 RWHP on 93. I figure I'm close to 900 on E85. This is a CTSV Wagon (ergo my posting here), and I have the NW102 now but have been hunting down some reduced engine power issues that I suspect are throttle body related.

If I have to replace the TB, I'm asking if anyone with a decent build has positive or negative experiences with the 112 from Kong/Nick Williams?

old motorhead

Have you checked to make sure you need a bigger throttle body? If you have no vacuum at WOT at max RPM between the throttle body and the blower, going bigger will only drain your back account. If you have a little vacuum and plan to spin the blower faster, then yeah, fit that bigger one.

Dayum! Sounds like a fun ride. Do you have the snout big enough to accept the 112?

Random84

Thats a good point- but I don't believe I have a pre-TB MAP sensor... just post-rotors. But I could be wrong so I will have to investigate.

Its a Kong 2650 so yes, it is ready to go for a 112.

I'd still love to hear from people who made the swap for what that's worth. They're out there... but i see few posts on it. Perhaps that's the answer!

0JUICED1

We've had some issues with them so far but others may have had better luck.

schpenxel

He's not saying anything about a pre TB MAP sensor. The point is to measure the resistance between the TB and the rotors, which is, in fact, the normal MAP reading. If you're already at atmospheric pressure at WOT, then there is no resistance and a bigger TB won't do anything. You're already getting all the air you're going to get in that scenario. Whether that's the reality for your setup, I have no idea.

Random84

My MAP sensor reads 233kPa when I give it full beans - that's my "normal" reading. I'm showing my ignorance here, but although I'm pretty sure this blower comes with 3 MAP sensors in factory form, ("Baro" and "MAP" plus another?) - I am not seeing the third active sensor in HP Tuners; which I suspect is the one you're referring to. I am guessing "Baro" is the pre-throttle body sensor, the "MAP" sensor is post rotor for boost - any guesses on what the third would be called?

CI GS

What oldmotorhead and schpenxel are saying is that you need to measure vacuum right in front of the throttle body at WOT.
There is no sensor for that. You will need to measure vacuum, with a vacuum gauge, in the intake tract in front of the throttle body.
If you see that it’s pulling vacuum there, then the throttle body is a restriction.
If the throttle body is a restriction, then you will pick up horsepower from upgrading to a bigger throttle body. How much will depend on the restriction.
The easiest way to do this is on a dyno, with a handheld gauge. I didn’t have that luxury, so I had to redneck engineer (duct tape) a vacuum gauge under my hood and aim a Go Pro at it to record what the gauge was showing at WOT during a test pass. I saw 3-4in. Hg, so I upgraded from my stock 90mm to a 102mm on my 2300 TVS Heartbeat setup and picked up ~1.5psi, iirc.
I have no doubt that you will benefit from a 112 on a 2650. Best guy to ask is Kong himself. He should know.

Random84

Thanks! yes, I had intended to Greg and ask, since there are conspicuously no "one user picked up X.XXX HP with our new 112mm TB!" on the website.

As it turns out, I am at the limit of my fuel system on E73 so it's become a moot point for this year.