Radiator for LS swap?

**MDS757** · 01-19-2015, 11:51 AM

Hello all, my project is a 04 LS1 in a 2000 740i and I am working on the cooling system. I found a radiator fan combo from ECP made for the S10 LS swap for $399. Looks like a good setup but the hose connections are 1-3/8" while the motor is 1-3/8" in and 1-1/2" out. Would reducing the outlet to 1-3/8" cause a problem? My thought is with the added cooling of the aluminum radiator would make up for any flow loss. Please let me know if you have any expertise or experience with this issue.
Mike

**JustinEntropyRad** · 01-30-2015, 06:21 AM

We are working on one for an E38 as it is...so maybe we can add the LS hose orientation and steam port barb as well.... I also work with ECP

**pajeff02** · 01-31-2015, 05:12 AM

I see no problem with the change in outlet diameter. As long as the replacement radiator has good airflow and ducting to keep the air moving into the radiator, rather than around it, you should be fine. I recently read somewhere why they design the outlet with a larger diameter (think it was a dyno tuning book), but do not recall the specifics. Lots of cars these days run the same size hoses top and bottom it seems.