Question about b20vtec turbo and 3b

erics99si · Post by **erics99si** » Fri Dec 20, 2002 2:46 pm

I have hondata3b on my b20vtec turbo boosting at 10psi. Everything has been tuned at 10psi to run perfectly. My question is (strangely enough), 10psi is fun as hell and I love the power, however it is kinda over powering for just street use (tired of burning up tires basically) and I was wondering how or what I could do to turn the boost down a few pounds without totally screwing up the previous tuning and not ending up flooding the hell outta my motor.

If I'm tuned perfectly at 10psi with the hondata 3B would it be bad to turn the boost down to like 8 or even 6psi? or would turning the boost down completely through off my tuning and end up flooding my motor (ie. Cars set at 6psi but the hondata thinks its still needs fuel for 10psi type of thing).

I'm new to hondata and I don't really know anything about it, other than I had to take the car to a tuner to get the car tuned.. can anyone help me out. My previous experiance was nitrous and just a upgraded FPR and pump. The higher shot I went the more I turned the fuel up, and everything was manually controlled (get out turn the FPR bolt, etc..) but I'm kinda weiry about turning boost down with the hondata and then running too rich. Do I have to go in and have it tuned again if I want the boost set at 6psi? Thanks in advance.

QUICKSILVER RACING · Post by **QUICKSILVER RACING** » Sat Dec 21, 2002 12:59 am

To turn the boost down, you have to set the wastegate spring at a lower boost. If you don't have a boost controller, I am assuming that you are using a 10psi Wastegate spring. You need to replace it with a 6 psi spring. With boost controllers, you can only go higher boost and not lower.

With regard to tuning, I suggest that you have it retuned at a lower psi. I checked the boost table and the site maps are 7psi and 11 psi. It extrapolates the values in between. To boost safely, the tuner has to tune the 3.8 psi site. It is not a question of flooding at 6 psi but it is also possible that you might go lean at 6psi.

I know haow it feels to have an overpowered car. I used to have a B20VTEC with JRSC and boostin' at 7 psi. I was spinning all the way through third gear on 15x8 slicks.

HOPE this helps.

erics99si · Post by **erics99si** » Sat Dec 21, 2002 11:34 am

Ya it helps a little, I do have a boost controller so I can turn the boost down with that. I used the wastegate spring to high boost but after 9psi I had to start turning up the boost controller to add more boost. So what your saying is I could go down to 8psi and I'll be fine as far as not leaning out, just maybe running a little rich (which can be good)? Basically I need to know, how much can I turn the boost down and still be safely tuned without going back in and getting re-tuned....7, 8, 9psi???

Don't get me wrong, I love the power, I just would like to put the power to the ground when wanted without spinning in town.... then I'll turn it back up on the track. My original plan was 10-12psi in town, 20+ on the track, however 1o in town is too much for my whoosy tires

.

QUICKSILVER RACING · Post by **QUICKSILVER RACING** » Sat Dec 21, 2002 8:42 pm

You have to know your wastegate spring pressure. You can't turn down the boost is the waste gate spring is set at a high opening pressure.

Yes, You can turn it down to 8 psi.

7 psi might move the map site to a different column.

But definitely you should still check the mixture.

I was running 6 psi when I was spinning tires. Thats why I am now finally setting up a turbo B16a for my daily driver. The B20VTEC is going NA. Still building the chassis. Backhalved. Trying to go 11's on a track that suck big time. The only one available here in the PI.

erics99si · Post by **erics99si** » Sun Dec 22, 2002 12:26 pm

Thanks Again for the input, sounds to me like I'll turn it down to 8 pounds. my wastegate puts out 9psi max fully opened so I'll turn the boost controller all the way down and then adjust the wastegate spring until I'm hitting 8 pounds.