Is anybody using speed based boosting on their FI builds. PROs/CONs?
I have an haltech and I am seriously considering either speed based boost or gear based boost to resolve traction issues at lower speeds. What's your thoughts?

 

When I get my car all complete I will be limiting my boost by vehicle speed.

Under 60mph, wastegate pressure only
Above 60mph....use boost controller to set desired bost.

 

that's how hal set my car up. up in chi were having a little bit cooler weather and i don't have too much traction probs. top of second and top of third can get just a tad bit squirly but it's nice because the car really just pulls, i don't have to feather the throttle. part of me is really mixed, because sometimes i just want it to hit really hard...but then i will just have tractions problems so the other part of me is glad he progressively ramps it in. i may be running another briguymax tonight, his best run was a 10.90...and can offer a fair comparison afterwards.

 

i would hate that...i want all power all the time and drive the **** out of it...get a good suspension and tires and lastly driver mod ...much more fun

 

it's not like the boost doesn't come on quick...from a roll if ur sitting in 2nd or 3rd gear the boost hits hard, i still have traction issues in 2nd for sure and if the tires aren't warmed up or if it's a little cooler out the top of 3 is a little squirly too...with how mine is setup i have to worry less about feathering the pedal for traction. but i can definitely understand where you're coming from.

edit: i'm running stock suspension with a nitto nt05 295 tire...they're pretty grippy. i just had the rear suspension aligned, they were able to set camber to -1.8 which is as good as it will get without doing any modifications.

 

I am running stance gt coilovers, -1.5 camber, and 295 nitto nt05 tires. With my current powerlab setup I hit full boost 16-17 psi at around 3100-3200 rpms and all h@ll breaks loose in first and second gear. I can only get traction if I 1/4-1/2 throttle in either gear. I can get traction in lower rpms in 3rd then loose traction at the top end. I can feather the throttle to avoid this problem but would like to do something about 1st and 2nd. I get dropped on short runs because of lack of traction.

How does the boost build with the speed based tune? For example is it: 1-2-3-4-5 etc psi or is it more like:7-10-13-16 psi. How much control does the tuner have in controlling the boost build??

 

i know its a little off topic but has anyone tried street slicks? i know driving in the rain or snow would be a horrid idea but at 500+ rwhp or mayby even 450 i really wouldnt want to drive in those anyway, but thats just my opinion so dont bite my head off. some of the sn95 and 4.6 mustang guys making 500-600 rwhp are able to hook up and have no traction problems with street slicks as thin as 245's. i know theres differences but still one would think running a 275 or 285 street slick would be able to make up for those differences.

 

if all you care about is going fast in a straight line then they may not be bad. i enjoy taking on/off ramps quickly as well as some other short roads in a spirited fashion...so the extra grip i may gain isn't worth it for me.

 

they make multiple kinds just get the ones for road racing, they arnt all drag racing tires =P

 

why not just tune the traction control to knock off a few degrees of timing when you start to slip. boost by speed is ok, but TC would be much better.

 

how easy would that be to do on a dyno?

 

+1 for slicks. A couple supra guys around here run around on street slicks and have no issues. Not talking bias ply drag slicks... lower profile road racing slicks.

 

i have mickey 305/35-18 drag radials.

even with that my 16psi on pump is nasty so i have closed loop boost setup by speed to help.

I've seen some people have it setup with wheel slip instead of speed. I would do this but under normal driving my wheel slip shows -6% so i'm confused on how much to adjust it since my baseline isn't zero. I'm sure i can set it up but it will take more time since -6% is basically my "0" wheel slip.

also, i couldn't even get the car from driveway into the garage on my DR's. In the rain it's wicked too. It will randomly break loose around corners which is ugly. If it's actual standing water on the road watch out. They hydroplane like you are driving on balloons.

 

i would assume your -6% is probably due to different tire diameter size. Taller rear tires wont be rotating as quickly as your fronts. if thats the cause, there must be a way to account for that in your TC since pretty much all sports cars are like that.

 

i would run DRs on the street because of corners but the road racing ones for sure i have a set of 285/35/18's picked out when i decide what wheels to go with, not sure what all 18's the akebono or w/e bbk fits under but that will be later down the road anyway after the drivetrain is done.(bbk not wheels and tires.) medium compound street slicks but ill prob only get 15k miles tops outa em guessing closer to half that


edit: my bad tires are actually 295/40/18 been looking at too many lately
http://www.tirerack.com/tires/tires....R8A6&tab=Sizes
i just need to do a little research see what wheel size is gona fit best in an attempt to only roll the fenders

 

ya, that's exactly why it's doing it so i think i'll just have to use -6% as my baseline of 0.