Will a HPI 58-63 w/ 6.2 injectors be too much for a crate 124 HC?
It's not too big. But an HPI 58mm would also be fine. The 62mm probably won't buy anything on that motor as far as power. If you plan to do more later, get the 62mm. Otherwise I'd get the 58mm.
Quote from: Ohio HD on May 10, 2020, 04:39:33 PM
It's not too big. But an HPI 58mm would also be fine. The 62mm probably won't buy anything on that motor as far as power. If you plan to do more later, get the 62mm. Otherwise I'd get the 58mm.
This^^^^^^
I'm using a 62 / 64 on a 11.3:1 120 with 148 hp/145 tq. No slow manners issues, great starting and goes like stink. If you're not building a high effort power house follow the previous advice. If you do have a stronger build or have plans for later the 58 / 62 up to the 62 / 64 will be fine.
There are members here using an S&S 66 Throttle Hog on 124 street bikes. It's in the tuning. Plan on getting a top tuner and device and you'll be OK.
Call Jimmy at HPI and talk to him. They've done lots of testing and tuning with their throttle bodies.
Ok, thanks guys. The only reason I asked was this is the second one I've installed, the first using all s&s 66mm TH, injectors, etc and that base map was emailed to me without any sort of disclaimer. When I provided the specs on the one it had a disclaimer of "requires extensive tuning". So I don't know if the disclaimer is a new thing or what. Both engines are using powervision and this one is only getting heat cycled before heading to the tuner.
Quote from: HighLiner on May 10, 2020, 07:53:12 PM
Ok, thanks guys. The only reason I asked was this is the second one I've installed, the first using all s&s 66mm TH, injectors, etc and that base map was emailed to me without any sort of disclaimer. When I provided the specs on the one it had a disclaimer of "requires extensive tuning". So I don't know if the disclaimer is a new thing or what. Both engines are using powervision and this one is only getting heat cycled before heading to the tuner.
I noted this with your map not as a disclaimer, simply a note that a combination of this nature will require additional tuning. You could use either TB with this setup
I am always amazed at how many people don't budget for a real tune on a performance ( or any) build. I can see where not stating that can cause you a lot of customer issues over their expectations.
Ive had a T124 with head work in 150's with a 58mm. Went to a 62-64 and gained nothing. On a stock crate 124 a 58mm is the ticket. Also, don't count on base maps. I've never seen a base map that wasn't greatly improved with a tune
I'm only trying to heat cycle the bike.
Im running a HPI 55/58 on a 11.3:1 124 making 151/148 and no issues. If I was buying new I would have gone with the HPI58 but since I already had the 55/58 I ran that instead. Both the builder and the tuner said that any gains with a 58 over what I had would be minimal if any and that it could affect the throttle response. Im very happy with the outcome
^^^Almost my words exactly....I'm pretty sure it's the same builder he mentioned your build!
"Im running a HPI 55/58 on a 11.45:1 124" making 152/154 and no issues. If I was buying new I would have gone with the HPI58 but since I already had the 55/58/1.80 intake runners I ran that instead. Both the builder and the tuner said that any gains with a 58 over what I had would be minimal if any and that it could affect the throttle response. I'm VERY happy with the outcome"