Got my mockup turbo this weekend (friend owns a shop and had a used spare laying around). The general size is correct so I can deal with placement and build the header. Ultimately I will get a new unit built that will be matched to the engine a bit better. There is a company here in Phoenix that will piece together compressor and turbine housings in whatever combination I want for not much more than what it costs to rebuild a used unit. As seen in the 3rd picture I'm going to have to relocate the oil filter and run an external oil cooler. I have seen builds on several F4is that placed the turbo ahead of the oil filter (see 4th pic), however that seems like it would made oil changes a real pain and required a scavenge pump for the oil return (see 5th pic). By relocating the oil filter, I can keep the weight balanced, have oil changes remain simple, and avoid a scavenge pump.

I'm not looking to make crazy amounts of HP (plan 7-10 psi), rather I want to be able to maintain HP in the mountains (rides to Prescott/Flagstaff/etc). I figure with the stock F4 rated at 110HP, a 30% gain gets me in a maintainable 140HP range while not stressing the stock bottom end too much since I have seen people adding a 20-30HP shot of Nitrous without issue.

 

Looks awesome, Good job, hear lot of people saying they are going to do it but no one actually going through with it.

Only thing is is if you are expecting a 30% increase you will only see about 120HP to the rear wheel as the F4 only has about 94HP to the wheel.

But anyways Keep us posted as alot of us would love to see a finished product and some dyno sheets.

 

True, but as it has been mentioned before the stock F4 is already "fast" enough. My real goal is sustainable HP so when I go on cruses I don't have such a hard time in the mountains. I hate the feeling of high altitude/"vehicle falls on its face".

The other reason for not looking for more than about 7-10psi is I do not want to over stress the internals. Forged pistons and rods would set me back $1500-$2000 (possibly close to what I'll spend overall on my bike build). So since I'm not looking to go "faster", I just don't see any reason in expense.

 

Very interesting. At what altitudes are we talking?

 

The places I can see riding are:

San Diego
Elevation 72–400 ft (22 m)
atmospheric pressure = 14.7 psi (sea level)

Phoenix, Arizona (where I live)
Elevation 1,150 ft (350 m)
atmospheric pressure = 14.2 psi

Prescott, Arizona
Elevation 5,368 ft (1,636 m)
atmospheric pressure = 12.0 psi

Flagstaff, Arizona
Elevation 6,910 ft (2,106 m)
atmospheric pressure = 11.3 psi

So quite a range of altitude and atmospheric pressure drop there. I get used to being in Phoenix and then any place North (in the mountains) the vehicle feels like it's dying. Hopefully (should based on my calculations) with the turbocharger I will feel the same (very close) HP at all altitudes. The only difference should be that it will take longer to spool up and get that HP from a dead stop at elevation. Low throttle settings will still be weaker due to low boost at low RPM, but mid-to-wide open should be fine.

 

Looks awesome! I want one for my track bike!

 

sweet!! there was a guy that worked next to me last year with a boosted busa that was nice but more than i would need

 

"Need" is such an unnecessary word (especially when it relates to HP)

 

lol im a fairly new rider, now my car on the otherhand can never have enough power