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Looks mad with that good WA red can keeping it company

Had a bit of time over the Xmas and New Years break to get a few things sorted. The dyno showed a couple of limiting factors, one was the cooler pressure drop and the other fuel pressure.

The intercooler was a cheap bar and plate, 530 * 270 * 76mm. It was for the stealth look, cant stand the cooler sticking out below the bumper. Couldnt really find any tube and fin of similar size so picked up a 600 * 300 * 76, and some cutting discs...
Cut two rows out and then removed the top cover, this also has the mounting bolts which of course the spacing was different to the old cooler (we wont discuss the rivet inside the mounting bolt hole holding it to the top cover, see that small hole near the end tank of the second pic and the messed up first pic...). So they got chopped and rewelded. Also welded in the 1/8 NPT bosses on each end tank for temperature and pressure measurements like the last cooler.
All pressure tested ok using water and a compressor at 40PSI. Trial fit was exactly the look I wanted....

Then it was on to the exhaust to get a pressure measurement happening... Test was less than successful. Exhaust pulses meant the data was useless. So either filter in software or hardware. Chose hardware as it also acts as a water and heat trap. This was just an old inline turbo oil feed filter, packed it with a stainless kitchen scourer... Working like a champ now. Quick test on just gate pressure shows 8.7 psi eMAP, 7.8 psi at intercooler inlet and 6 psi in the intake manifold. Overall pressure ratio of 1.45 including the intercooler drop isnt too bad. Will be interesting at higher boost pressures.


Last thing was fuel pressure dropping off under boost. Learnt a fair bit about return lines here. You need bugger all, but cant be too small either! Fuel pressure was ok until about 9 psi and then was around 6 psi off target (50.5 psi base + 9, should have been close to 60 but was low 50s). So rewired the pump as there was about 3 volts being dropped at full load with the factory wiring, its a 340LPH pump so not surprising. Thought job done, fired it up and my fuel pressure at idle was 8 psi higher and the reg wasnt able to control it any lower. I do have PWM pump speed control but still wanted a system that can operate at 100% DC at idle.

At this point I learnt how small a return line can be. The TurboSmart FPR1200 V2 has a -6 return fitting but only a 4.5mm orifice inside the reg. Do the math and with a 50 psi drop across it thats a crapload more than 340 LPH of pump. So the restriction wasnt there. With the return line at the tank in to a jerry fuel pressure was spot on, the in tank venturi size is too small So until I find a better solution the return line now goes directly in to the swirl pot.

Love your work.

You are the king of engine data collection

nice work on the cooler and the sensors

I am very eagerly awaiting more PSI in this thing and I don't mean fuel pressure

The cooler ended up totally awesome. Good work on the data and calcs too. Excellent, all around.

Dudes got tiggin' skills, daaammmm

Awesome work as usual. FPR regs are best on market i reckon, used a few on my inj rig and fpr was most consistant

VL400 wrote:... for the stealth look, cant stand the cooler sticking out below the bumper.

Very good call, and well worth the effort!

nothing worse than coolers on VL's scraping the ground. mine had a GKTECH cooler from a billion years ago painted black you could never see.

its amazing how some reporting/data used with proper analysis can net you the results you need. thats really good stuff there mate.

Thanks fellas. I do like my datas