First, I loved my 370's for the last 3 years and about 30k miles. I was able to finally get some ddp 4's. I pulled my 370s, using the lug but method, worked great. I used 1/2 mm or .020 washers per ddp on the 4's for the install. Cleaned the bores, wire brush, q tips, carb cleaner, air hose. Greased the ddp4, washer and body lightly, and went right in. No leaks.

EGT's are lower, I run a 4000 gsk, a 10 full forward. Smoke is very very much decreased. Virtually no smake till after 1/2 throttle. The 370's were more sensitive down low and hard for non deisel drivers to drive. The ddp'4 cool faster also. Basically were the 370's would be around 1350- 1375 the ddp's are at 1250-1290 degrees. The ddp4's still flow the coal when you lay into em and IMO are better then the 370's everywhere. I ve liked the 370's, they have been great, but it appears this is a case of you get what you pay for. If you can afford ddp4's get them, if you dont want to yet, the 370's are good. Im impressed and have my 370's forsale.

 

So my question is how much more seat of the pants power? I would love to go this way but the pocket says No. But if there is a huge increase in power that may have to happen some day.

 

Honestly I d say there is no seat of the pants difference. It starts alittle easier, idles alittle smoother, smokes less. Basically all drivability. I dont think you could tell which was which blind folded.

Now I m gonna swap on a coated 3 peice ported manifold. Then coat the exhuast housings at some point. It would be nice to get a 700 dyno at somepoint, but it doesnt really matter I use it to tow a 50ft GN trailer, ussually the trailer comes in at 22000 to 25500.