12 replies to this topic

[AFDoc]

Hey guys, wondering if you think this mod is worth it or not. I have a Roto-Fab "CAI" and Solo Mach-X exhaust. Will the Fastman mod to my TB do much for me? One of the things I've seen people brag about it is the immediate response they get after the mod versus the lag. I don't now have any lag at all. When I mash the gas, she goes...now! Thanks in advance.

[70Barracuda]

I don't have the Fastman throttle body but I do have the BBK 85 mm throttle body which should be about the same. Although I've heard different people say they felt an improvement in the throttle response when they upgraded, I can't say that I noticed any big difference.

I do believe though from seeing different dyno tests on throttle body installations, and my own personal experience at the drag strip that it is good for a few horsepower. I did some before and after installation testing at the drag strip and pretty much concluded that it was good for a tenth or more in the quarter mile. That kind of improvement is pretty much not something you are going to really feel, however I like to pick up as many tenths as I can so it was worth it to me. It is also an incredibly easy mod to install.

[rdrdr90]

4 rwhp gain for me. I made NO changes between dyno runs other than the TB on the same dyno, and temp and humidity were almost identical. Different days, but that was the only difference. I bought a new TB from him and had him port it, so I still have my original.

[DTECH]

4 rwhp gain for me. I made NO changes between dyno runs other than the TB on the same dyno, and temp and humidity were almost identical. Different days, but that was the only difference. I bought a new TB from him and had him port it, so I still have my original.

An engine that was cooler than before will gain you hp ...to have an actual comparison it needs to be back to back after equal cool down and warm up periods....

[rdrdr90]

Sat for an hour both times before the dyno runs drove the same distance to get there.

Point being, negligible gain.

[Jay6spdRT]

I was gonna say.... 4 rwhp easily within the accuracy range of the dyno itself.

No easy gains with these cars, for sure.

[70Barracuda]

Hemifever had a pretty good write up and dyno test on the BBK 85mm throttle body awhile back, he ended up getting 11hp. Here's a link to his test. http://www.challengerforumz.com/showthread.php?t=58524

Mopar Muscle magazine also did a dyno test of the throttle body back in 2010, here is a link to their dyno chart and write up http://www.moparmusc...t/photo_09.html

They claim 15 horsepower which seems a bit much but that's what their chart shows.

[AFDoc]

Thanks, all. Any downsides? I've seen some posts on some other ChiThole forum talking about revving and limp mode issues around the Fastman TB.

[rdrdr90]

Thanks, all. Any downsides? I've seen some posts on some other ChiThole forum talking about revving and limp mode issues around the Fastman TB.

I hand ported one and I got the codes (could have been a bad TB that I bought used), I've had no issues with the Fastman one. That is why I bought a new one from him, and had him port it, to keep my stock one in case I got the ETC codes again.

[curbfeeler]

I ordered one from him also -- I think he's a little backlogged with orders right now.

I'll post my thoughts after I get it put on. Some say they've gotten improved throttle response, maybe it's all a placebo effect...

[KeavDog]

Interesting... what did the TB run you? do you have to change out the coupler from the rotofab to the TB?
If its worth a tenth I'm in.

BTW is it worth it for a SC car vs NA?

[rdrdr90]

Ran around 200 all in if I remember correctly. I would think a SC car would benefit much more than a NA car, or it makes sense that it would.

Easy and relatively cheap mod.

[curbfeeler]

I installed mine this afternoon. Quick and simple, just the four bolts holding it on (I also kept my original).

On mine, there is a very thin whitish-colored gasket that runs the circumference of the intake port where the TB meets it, which slipped partly off when I took the old one off. I re-seated it carefully and put the new TB in and replaced the throttle control sensor. After everything was back in place, I started the car. It idled at around 1100 or so for several minutes before dropping down to its usual 750-760 RPM.

I then took it for a ten or so minute drive.

It's difficult for me to be objective, but the throttle response is at least as good as it was with the original. It was responsive through all gears and varying RPM ranges. It's certainly no worse.

Worth it? <shrug> In my case, all of my upgrades are very much piecemeal at this point, so I look at it as somewhat of an investment that might nicely complement future upgrades. We'll see.

Maybe I'll notice some difference next time I make it out to the track, which should be Wednesday I'm hoping.