Project: The New CDD Shop Truck

ShadetreeV

Full Access Member
Joined
Oct 5, 2017
Posts
112
Reaction score
70
Location
Redding
Wow!
I'm really looking forward to seeing some progress on this. More tunability may help unlock some potential out of a compound setup as well?
 

Thewespaul

Supporting Member
Supporting Member
Joined
Jul 27, 2015
Posts
8,796
Reaction score
8,058
Location
Bulverde, Texas
Chillman pretty much nailed it, there’s much more tuneability with the in-line pump, and it’s a completely flat fuel curve so it doesn’t taper off at higher rpms which that aspect of the db2 really affects the power curve of these engines, since these engines have the air flow and valve train to handle higher rpms well, but the fuel system can’t meet it. The 3208 pump conversion is going to be a big project, and not a speedy one since there will be a lot of r&d, and a lot of time and money out of pocket.

Once the pump gets here I’ll start a separate thread for it, since by the time it’s ready to go on an engine I may have a race/dyno dedicated truck that it will go on, instead of the shop truck. Once I can see that it performs off the street in a controlled environment then it will go to further iterations to be on the street trucks, and maybe even be marketable some day.
 

Thewespaul

Supporting Member
Supporting Member
Joined
Jul 27, 2015
Posts
8,796
Reaction score
8,058
Location
Bulverde, Texas
Had a bit of time while waiting on parts to do some work on the truck, pulled the engine harness off and took my worst spare harness and stripped everything out that I didn’t need. I have a custom fuel filter setup so don’t need any of that, oil pressure switch isn’t installed so I removed that, don’t need glow plugs or high idle when it’s 95+ everyday, I’ll build a manually controlled glow plug harness when/if it gets cold enough here to need it. Widdled down a few other things and went from this:
You must be registered for see images attach

To one wire for 12v to the injection pump. Didn’t cut any wires so I can still use everything for repairs down the roads, just pulled the connector apart and removed each pin with the wire until I was left with this:
You must be registered for see images attach


Zip ties holding it together since the clip is long gone.

Looks a lot cleaner on top of the engine, and much easier to diagnose electrical issues when you remove everything you aren’t using.
 

Thewespaul

Supporting Member
Supporting Member
Joined
Jul 27, 2015
Posts
8,796
Reaction score
8,058
Location
Bulverde, Texas
Threw together an intake with a 1” barb for the cdr vent
You must be registered for see images attach
 

Thewespaul

Supporting Member
Supporting Member
Joined
Jul 27, 2015
Posts
8,796
Reaction score
8,058
Location
Bulverde, Texas
Heading to the track for test an tune, gonna be interesting to see what it will run, I’ve got a boost leak now from the broken intake manifold, so only getting 11-12psi but egts aren’t an issue.

Best run na with the old motor was 18.9 @69 mph but that was with fuel pump issues. I’d be happy with 16s the way it sits now, place your bets on times now!
 

Thewespaul

Supporting Member
Supporting Member
Joined
Jul 27, 2015
Posts
8,796
Reaction score
8,058
Location
Bulverde, Texas
Well its always a fun night at the track, most importantly the truck drove an hour there and drove home no issues. First run was a disaster, 17.9 @82mph and holy axle hop batman! Ive never had it leave that poorly, it hopped all the way through third gear and that was just flooring it off idle, but with that mph I should be in the upper 16s if I could get it to 60 ft.

So I dropped the tire pressure, turned the boost down a touch since it was not smoking at all, and left very soft. Half throttle in first and and second but as soon as the boost kicked in it was getting into the hop cycle.

Several runs in with further tire pressure, boost and driving adjustments I was able to drive almost a second off of it, with no improvement to mph. Best run of the night was 17.1 @ 80. Didnt meet my goal but definitely a ton of fun. In order to get that et I was short shifting and pretty much half throttle till 40 mph to get it to hook.

Plugging in my et and mph in a hp/weight/et calculator it puts me at 252 rwhp. Granted this is an estimator, so a dyno will be coming with some real numbers, but this et gives me a great baseline to improve on. Traction bar build coming soon!
 

ShadetreeV

Full Access Member
Joined
Oct 5, 2017
Posts
112
Reaction score
70
Location
Redding
Chillman pretty much nailed it, there’s much more tuneability with the in-line pump, and it’s a completely flat fuel curve so it doesn’t taper off at higher rpms which that aspect of the db2 really affects the power curve of these engines, since these engines have the air flow and valve train to handle higher rpms well, but the fuel system can’t meet it./QUOTE]
Curious, how high of an rpm can an idi handle properly built? While still making torque.?
 

DaveBen

Supporting Member
Supporting Member
Joined
Sep 29, 2010
Posts
1,915
Reaction score
632
Location
Ukiah, Ca
You can't have both torque and high revs. Diesels are not designed for rpms (over 5000 rpms). They are made as torque machines. If you want to rev the stuff out of it, stick with a gasser.
 

ShadetreeV

Full Access Member
Joined
Oct 5, 2017
Posts
112
Reaction score
70
Location
Redding
I understand the limitations . Diesels inherently have a lower operating rpm range due to not only reciprocating mass but at a point fuel delivery and burn rate come into play. Also relying on the pre cup chamber vs a direct injection setup I was curious how high of an rpm you can still make power with an idi.
If I wanted revs and still keep it diesel I'd go with a detroit two stroke haha.
 

Thewespaul

Supporting Member
Supporting Member
Joined
Jul 27, 2015
Posts
8,796
Reaction score
8,058
Location
Bulverde, Texas
The stock fuel system is the limitation for rpms, the db2 just can’t carry the fuel curve much 3500rpms. I think with the inline pump peak power will be from 3500-4000 rpms, and I’ll be going as high as 4500 if air flow and valvetrain carries the power that high
 

Jason1377

Supporting Member
Supporting Member
Joined
Dec 12, 2017
Posts
975
Reaction score
386
Location
Arkansas
Heading to the track for test an tune, gonna be interesting to see what it will run, I’ve got a boost leak now from the broken intake manifold, so only getting 11-12psi but egts aren’t an issue.

Best run na with the old motor was 18.9 @69 mph but that was with fuel pump issues. I’d be happy with 16s the way it sits now, place your bets on times now!

Curious as to what tire size u had such as stock etc as well as does it cost per run or you just pay a certain amount for the night at a track
 

Forum statistics

Threads
91,217
Posts
1,128,469
Members
24,043
Latest member
tottripp

Members online

Top