DDII's, or Don M 1.5's?

[Gary - K7GLD]

HELP!



I'm ready to upgrade my '02 HO/6 speed with a 4 inch exhaust and bigger injectors. I've heard a fair anount about the DDII's, but not a lot about the Don M 1. 5's. I've been told they are pretty similar in power enhancement, but that the Don M's are more aggressive in lower RPM, and smoke less under heavy throttle. My truck is used primarily as a tow vehicle for a 5th wheel, so EGT comparisons would help as well - current mods are listed below, and consist of a Comp and BHAF - that's it so far.



All pertinent comments, especially first-hand ones, would be greatly appreciated! OH, and is there a website for Don's stuff?

 

[Tcolesanti]

www.formula1diesel.com

I have Don's 1. 5's and in conjunction with my old VA box and now with the Comp set on 1x5 they work flawlessly even with the stock turbo. I tow quite a bit (heavy too) with my set up and I love the power it builds down low. I would however recommend going to a hybrid 35/40 to make the most out of this combonation. I am not saying it will get hot but when you turn the comp up it will. Hope this helps.

 

[Gary - K7GLD]

After looking at Don's website and various injector levels, I'm now wondering if maybe the 2's are do-able for my situation and setup? I'd like to get the maximum workable level for the towing I do, and with the BHAF, Comp and 4 inch exhaust - without having to watch the EGT's like a hawk - lotsa power is pretty pointless if you can't use it...

 

[PC12Driver]

I've towed with the 2's, and they're very controllable EGT wise. They start well in cold weather, idle smooth, and don't smoke too badly for a 100hp injector. They also have a nice romp-romp-romp when feathering the clutch while manuvering into parking spaces. Highly reccomended.



And for towing, leave your turbo alone. I went with the DZ w/14cm exhaust housing and it borderline sucks for towing. Giving it any throttle below 1900-2000 rpm and the egt's would rise faster than the boost (I'm "under" the turbo at that rpm). It makes for a lot of pyro watching and downshifting in the hills. I talked it over with Van Haisley when I dropped off my head for a bit of work, and he suggested putting the stock turbo back on. The 'ol hx35/12's useable rpm range is right where you need it to be for towing. In fact, his favorite turbo for his 450hp and lower trucks is the hx35/12 from a '97 (slightly bigger compressor wheel, something close to the PDR 35 I think). Yeah, it gets hot on top, but it actually runs cooler at low/mid rpms where you actually use it the most. The big compessor of the DZ generates a lot of drag (compared to a normal sized 35) and needs a lot of airflow (more throttle and/or rpm) to get it to spool.



So, when my truck goes back together I'm going to try the DZ/14 with the new cam ( ) and see if that gives me enough airflow to spool up at lower rpms. If it doesn't, I'm gonna put the stock turbo back on and save up for a set of twins with an HX35/12 for the top.

 

[Gary - K7GLD]

OK, as it now stands, I have committed to Rip Rook for an installed set of F1 1. 5's, and a 4 inch exhaust system involving dual baffling (mufflers) to avoid drone or resonance - these are to be of straight-thru design for low back pressure.



This was after lengthy discussion with Rip, and I still have 2 nagging concerns. One is that the 1. 5's are REALLY the maximum usable for my typical use and other associated mods - and the other relates to the use of a 3. 5 inch turbo downpipe whereas the rest of the system is 4 inch.



Rip claims the 3. 5 inch downpipe enhances low end torque, and is entirely suitable for up to 450 HP - my finished setup SHOULD be good for about 400 HP.



Rip comes highly recommended - and I sure hope he is correct on all counts here - I really DON'T wanna have any regrets or second thoughts after the time, $$$ and effort all this will involve...



Wish me luck!



OH, and I received quite a few (much appreciated!) offers for used injectors from this thread - I very much appreciate them all - but feel I really should buy the products from the guy installing them, in case of later issues that might occur.

 

[24V-DSL]

Gary...

Unless Rip has changed his "mission statement", (trust me, he hasn't) you won't be unhappy.

 

[Gary - K7GLD]

"Unless Rip has changed his "mission statement", (trust me, he hasn't) you won't be unhappy. "



You know, I'm sure you are absolutely correct - all contact with him so far has been 100% positive - I'm mainly anxious that *I* have adequately communicated MY expectations and goals to HIM, not that he would in ANY way short me on final product!

 

[JJ Jackson]

Hey Gary, I've been following your quest for injectors and I too went to Rook for some injectors. I went with Mach 2's with a stock HX35/12. If it gets too hot I told him I would probably be talking to him about a bigger turbo. I ordered a FASS from him too. It hopefully will get here before Saturday so I can work on it this weekend. He also said he would buy my 275's from me, and sell me the used set of mach 2's to sweeten the deal. Anybody else gone fom 275's to Mach 2's? Am I gonna be happy with the power unloaded and when towing?..... Jim

 

[Bob Wagner]

"Unless Rip has changed his "mission statement", (trust me, he hasn't) you won't be unhappy. "



You know, I'm sure you are absolutely correct - all contact with him so far has been 100% positive - I'm mainly anxious that *I* have adequately communicated MY expectations and goals to HIM, not that he would in ANY way short me on final product!

Gary, *IF* not Rip has dealt with a few **&^%$^^** customer's in the past.



you will be fine :-laf