Which is better for towing? I already have hx 40 with s475, very fun setup with ddp150's and my setup. Would it be beneficial to swap to a he 351 for towing my 18k toyhauler. I also have 3.73's in the rear now. Thanks in advance

 

have you tried to tow with your current setup? id try that first.

 

he351cw would require changing your twin piping...

it would be cheaper/easier to change to a S300 turbo like a 57/65/12 or 57/65/14.

you could also go to a 62/65/12 or 62/65/14

the 12cm^2 housings will spool faster, but cost more.

14cm^2 housings are dime a dozen and very common to find.

either way they will definitely spool better than your hx40 with its 16cm^2 housing.

also any S300 turbo will last longer than the HX40 as they are built better and have MUCH stronger shafts.

 

I agree with Rooster. What are the results of towing with your current setup? We have similar setups, and I didn't break 1300* pulling my 39', 14,000 holiday trailer with a 16cm turbine housing on my hx35/40. Since dropping to a 14cm housing, the temps have slightly reduced and low end has increased.