I must be a bastard on this one

Just taking it flat:

G: 6.67x10^-11 (m^3/kg*s^2)

Delorean: 88 mph ---> 39.3 m/s

1/G= 1.5x10^10 (kg*s^2/m^3)

(1/g)/Del = 3.81x10^8 kg*s/m^4

Which kinda works except that since both numbers are already in different units in their preferred mode this is kinda silly, however, a given unit system for G is fairly irrelevant, whereas 88 mph was very symbolic for the movie, infinity being the lazy 8 and 88 being fast for a car, so properly Kronin's bid should be in the appropriate system using miles and hours

G - in miles and hours, using the slug as a substitue for kg: 2.07521342214×10-^13 mile3·kg-1·hour-2

Which divided by 88 mph would give a far more legit 5.46x10^10 slug*hour^2/miles^4

However, one feels the random choice for mass units is also inappropriate, and as we are working with the Eddington number, which is essentially a count of protons in the Universe, that the mass of a proton should be used, or the AMU, the standard way to measure mass when dealing with protons and neutrons, clearly the amu, not the slug or kilgram, is the appropriate choice - in which case G:

G = 3.44597253675×10-40 mile3·amu-1·hour-2

Which give a far more appropriate 3.2938076416337285902503293807642x10^+37 AMU*hour^2/mile^4 placing him above Gher and beetnemesis's bids, I believe, a far more appropriate result for someone who bid a dimensioned figure