ben
Yes we have tested the 15 row unit versus the V4 and versus a stock intercooler, you can expect to pick up almost a tenth more on a low 12 second buick with our 15 row versus a V4 unit, versus a stock intercooler, our 15 row unit will gain you almost 1/4 second witht proper fueling and modifications (again this was with us testing on race gas/ vs/ race gas when we swapped the coolers, so the gains on pump gas would be in the 3-4 tenth range. The 15 row unit we build has been a relatively unchanged design for the past 15 years...we have changed the neck casting which flows better than a std dutt neck and any others on the market. It is a great buy for the money, but you've gotta give up your stock intercooler as a core!
The new unit simply BLOWS ANYTHING on the market for the stock location outta the water...Thanks to Rick Jensen, editor of GMHTP Magazine we have PROVEN DYNO results and thermal efficiency calculations that are dayum near that of a similar front mount unit, plus you do not have 6 bends going to the intercooler (front mount) you only have 3 bends with our unit...We have calculated that on a high 10 second buick, in 3" mandrel bent tubing, per each bend you LOSE 1 POUND OF BOOST for every bend going to the intercooler and back to the throttle body at high RPM powerband. Many here will argue with us about this subject, over and over again, but we have the test results and you can come here anyday of the week and we'll stick a 3" aluminum 90 bend on the flowbench!!!

You will argue with me because you say that:" well....I picked up 4 PSI at the motor with my front mount.......that is BECAUSE THE CORE IS MORE EFFICIENT and can move more air/per time as compared to whatever you had on it before, has almost nothing to do with the bends it is a DIFFERENT part of the intercooler...
Front mounts are cool, they work, and I would say anything faster than 9.20s you would benefit from a LARGE front mount such as the cottons unit...
Hope this solves some wonder and any more just ask, BTW the V4 was tested versus our intercooler(15 row) and versus a stock intercooler by Daryl Riegel of the now latent TurboBuick Newsletter at Cecil County Dragway in MD, in the presence of Jack cotton, eric schertz, myself and many others....its a proven "old school" mod!!!
