Gus Mahon wrote:
In September of 1988 I purchased a new 1989 Dodge Caravan with the 2.5 turbo 1 motor. It's best quarter mile was 16.5 sec. on a cold night. I threw in Mobil 1 oil, @ stuck on a K@N air filter. My muffler man welded a 2.5" exhaust pipe onto the back of the cat, with the cat acting as the muffler. At New England Dragway the mini cut a 2.437 60' time, and 16.182 @ 84.11 mph.
I put in colder spark plugs, a colder thermostat, & bled the boost to 12.5#s. Back at NED the mini ran 16.01 @ 84.58. The van got a manual fan switch (to keep the fan on at the track). I put a solenoid air valve on the wastegae line bleed-off so that I could control boost from a toggle switch on the dash. That way I could leave the line on 5 lbs. without spinning the tires, then flip the switch up to 13 lbs. while under way. This produced a 2.38 launch, & a quarter of 15.766 @ 85.86 mph.. A little practice with the HI-LO switch= 2.28 60', and 15.558 qtr mi.
A 13# pop-off valve was made & installed on the map sensor line to keep the stock computer from shutting me off at high boost. I threw on a Spearco intercooler and ran 15.111 @ 89.45 mph.. My Cyberdyne rich-lean gauge told me that fuel was needed. I installed a pinch-valve on the fuel return line to close the return as the boost climbs in order to raise fuel pressure. 14.854 @ 91.40, at 14 lbs. boost.
The 3 speed auto tranny was beat up. After a beefed up rebuild, & a hike to 15.5 lbs boost, Mean Mini cut a 14.563 @ 92.75 mph. Keep in mind that this was a 3,250# vehicle with 30 sq. feet of frontal area. In 1991 I ran a single NOS fogger nozzle rated 70-80 hp., and pulled a 13.43.
In 1992 I got rid of the nitrous, after deciding to beat my record without it. I found myself back in the 14.6's. I added an extra fuel injector on the intercooler tube 6" before the throttle body, turned on by a pressure switch at 14#s. The coil was moved closer to the distributer, and a short solid-core coil wire put on. Sticky street legal tires were mounted on 15" aluminum Daytona wheels. Two coils of each spring were clamped together to stiffen the suspension, & lower the van. 100 lbs of weight was removed from the rear half. I took the balance shafts out of the engine. At NED the 60' time was 2.217 w/ quarter mile of 14.170 @ 96.03 mph.(18lbs boost) 13.949 turned out to be the best time possible on the tiny Mitsubishi turbo, which could not pruduce more than 18.5 lbs.
I knew a Garret would flow much better, and that a Super 60 would be better still. The super 60 turbo, with a 3" exhaust, ran 13.764 right out of the box at 97.67. After the addition of a sixth injector and positraction, Mean Mini cut a 2.08 60' time, and a qutr of 13.569 @ 99.80.
In September of 1994 I drove 330 miles to Cecil County Dragway in Maryland. The van out-accelerated 7 cars out of 7, was the quickest daily driver there, and cranked out a 13.484 @ 101.36 mph in 95 degree heat. Then she packed up and purred home after churning out 26 lbs+ boost with no trouble.
At NED, on a 75 degree Saturday afternoon, I made 2 passes with my new underdrive pulley on. Boost was 27 lbs. The tires spun (2.194 60') to a 13.475 @ 102.29 mph. On the second pass the tires spun less (2.025) and gave up a 13.184 @ 102.57 mph.
The minivan has been on the back burner, as my 12 second Acclaim has taken up my racing time, but the van WILL run 12's in 1998!
Postscript: it did run a 12-second quarter mile. Gus has, since that time, been killed by a careless driver in a motorcycle accident. He was known as a helpful, friendly, and very resourceful person, and is missed.
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