As expected, the only drawback from installing the larger intercooler is the slightly longer time it takes to fill the core, which contributes to turbo lag. However, it was only less than 100 rpm slower to react until the second turbo came online.
One thing we realized with these last dyno runs was that Project Supra is maxed out at about 370 whp on California's crappy 91-octane pump gas. In order to see what our end results would be with the stock turbos we added a few gallons of Sunoco 112 octane racegas to the mix. With what is now approximately a 94-95-octane gas mix, the EMS-controlled wastegate was set to stay closed a little longer. To our surprise, the turbos wouldn't boost manifold pressure past 17 psi. Karamikian adjusted the timing a bit and was able to coax out a maximum of 395 whp and 376 lb-ft of torque.
Our numbers may sound a bit on the low side when considering other Supra owners have seen over 400 whp at similar boost levels with the stock twins. However, a quick check of our compression told us something was wrong in the #4 cylinder, which was down nearly 40 psi. Couple that with a nearly 100k mile engine/turbos and you can see why the power drop is possible.
(Horsepower): new Baseline, 16 psi (Blue); Turbonetics intercooler, 15 psi (Red); Turbonet
(Torque): new Baseline, 16 psi (Blue); Turbonetics intercooler, 15 psi (Red); Turbonetics
(395 whp graph): In the end our arthritic engine came up with 395whp on a fourth gear pul
So where does this power drop lead us? Whether it's a bad valve or a bad piston ring in the #4 cylinder, it won't matter for long. The entire engine will be undergoing surgery and receiving much stronger internal organs at Speed Force Racing. By the time you read this we'll hopefully have the tuning done and the car dyno tested with its new lungs-an SP71-GTQ turbo kit from Sound Performance. Yes, it's going to get a lot more fun now. Stay tuned.
Author's note: At this year's Hotchkis Media Challenge our Supra DNF'd during its second run on the dragstrip when trying to slip the clutch during a 6000-rpm launch. The disc seized to the flywheel and the car wouldn't run once put into gear. We replaced the unit with another Centerforce unit, which we will be testing the torque limits of with our new setup, as well as a Fidanza lightweight flywheel. Special thanks to RJ and Matt Hunt of UPFD for taking the car in on a Friday evening and having it ready the following business day.
According to Calicchio, many companies make intercooler kits with piping going from the in
Eosport's Gary Karamikian was once again in charge of tuning the AEM EMS. As you can see,
Shortly after the intercooler tests, UPFD installed a Fidanza flywheel. At over 20-pounds
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