I-6 Help

[mdapperdan]

I have the chance to purchase a wrecked '97 Dodge and before I spend all that cash My question is what are the advantages or disadvantages of the
12- valve verse the later model 24-valve engines.
What I'm looking for in a I-6 is reliable pulling power not a race machine. I will be installing this in a '79 GMC dually.
Thanks Dan

[Swayse]

The 12 valves have the inline injection pump. I've heard about 2 mpg better than a 24 valve. Easier to turn up the power. Not as loud as a 24 valve. More reliable and easier to work on. But check out www.turbodieselregister.com

I would do it if the price is right

[Rebel_Horseman]

Ditto what Swayse said. The old 12 valve is not made for racing (in stock trim ;) ) but it's an excellent motor. You will get slightly better fuel mileage over the 24 valve, the mechanical injection pump is a little more reliable in my opinion, and you can easily get more power out of the motor for less cost than a 24 valve. I have a friend that wants to do the exact thing you are talking about doing. He wants to find and old 12 valve motor and put it in an old Chevy body.

Reb [><]

[WKener]

Since you are doing a swap-in, I highly recommend sticking with the 12 valve motor. The mechanical injection pump (bosch P7100) has it's adavantages over the 24 valves VP44 pump, one being it's lack of electronics. Another is ease of maintenance and peace of mind. The VP44 in the 24 valve is not likely to quit on you, but since the lift pump used in the 24 valve seems to fail every 50,000 miles or so, if it's not monitored it can take the VP44 with it.

As others have pointed out, the P7100 is very easy to upgrade. If the '97 you are looking at has a 5spd transmission, it is a 215hp model pump and can easily make 300+hp/600+tq for less than $300. For another $250 you can get that pump to fuel beyond 4000rpm if you are so inclined.

If you decide on the 12 valve, make sure to check the KDP. This stands for "Killer Dowel Pin," and is the only real flaw with these motors. The timing cover is aligned with several press-fit dowel pins, one of which has been known to work itself loose and fall into the timing case. When this happens the pin will be knocked around by the timing gears before it gets shot out the cover, creating a massive oil leak. Upon failure, that is your best case scenario. Most likely the pin will run between gears, taking out the camshaft and other vital organs. This is not good, and can easily be prevented for free (or $150 or so if you pay someone to do it).

I am not sure if you intend on using the transmission out of the wrecked dodge, but if you are and it is a 5spd then you must be aware that the retaining nut holding 5th gear can work itself loose resulting in no 5th gear. 5th literally falls off. This does not affect the drieability of the other 4 forward gears, but is a pain in the arse. There is an updated 5th gear nut, and a fully splined mainshaft available as well to nullify this problem.

Overall, the 12 valve is known to get slightly better fuel mileage, but I think the real advantage is: The 12 valve requires NO ELECTRICAL CONNECTIONS other than power to the grid heater (besides the starter/alternator/obvious stuff).

[mdapperdan]

Frist of all I want to thank everyone that has had a comment on my questions. Second of all I'm not as knowledgble about this motor as some but I feel I can get good advice when ever I have a question
for other members on the forum

[mdapperdan]

Frist of all I want to thank everyone that has had a comment on my questions. Second of all I'm not as knowledgble about this motor as some but I feel I can get good advice when ever I have a question
for other members on the forum