kino_fab
KTPA Tech Official
After reading this thread I have seen alot of good points made and repeated from over looking and with them all being placed in different parts of this thread. So i figured I would pitch in my $.02 on the situation all in one post to help enlighten a few. I haven't done this conversion, but I have looked into it quite a bit. A friend of mine is doing the same thing on a 2.6 puller (not mentioning any names either, he keeps things secret). I stopped by his shop a while back and asked him about how the build was going and seen the beast sitting in front of me.
Here is what I know and what he has told me.
Front gear case: it is alot simpler to just buy a gear case made for a CR/P-pump, but you can use the 12v case. Although in order to use the 12v case you will need to re drill and tap the block to get it to work. If I remember right, he told me that only 2 of the orginal holes in the 6.7 block lined up. And yes it is a ***** to do and time consuming, but it may save you alot of money in the long run.
Oil pan: correct me if I am wrong, but the CR oil pan will not bolt up to the 12v gear case up front. Not sure if the mating surfaces are the same either. I believe I have read where a few people have cut the front off the CR oil pan and grafted the front of a 12V oil pan on to it. Although, if the mating surfaces are the same, I would say all you really need to do is fill in the original front mounting holes on the pan, and re-drill the pan to bolt up to the 12v gear case.
Gearing: Just save yourself alot of $$$ and just use the 12v or VP24v gear set. The cam and crank gears are pressed on. If you are super careful, you can remove the CR crank gear using a die grinder and a cold chissel and hammer. Carefully grind a groove in the gear at the dowl pin area of the crank and crank gear leaving a little material of the gear at the crank. Be super carefull not to nick the crankshaft at all. Then take the chissel and carefully strike the gear in the groove you just ground out. The gear will then split open and with alittle elbow grease, it will come off. Another thing to try would be to grind out 2 sections of the teeth at the back of the crank gear. Both sections being 180* apart. Cut the 2 sections just big enough for a 2 finger gear puller to firmly grip the gear. Next place the gear puller on the crank and put pressure on the jack bolt. Some may come right off, then others you will have to heat the gear with a torch. The cam gear can easlily be pressed off and on using a hydriloc bottle jack press. I wouldn't recommend using the CR cam gear. It is only half the thickness of the 12v and VP24v cam gear, and it wouldn't last long in a high hp/big pump application.
Cylinder head: If using a CR head, you will have to modify the intake plenum or completly remove it and build your own plenum or individual runner intake. For those using the original intake plenum, you will need to cut a section of the plenum out to clear the Governor house on the P-7100. I believe you can weld in a patch panel on the inside of the plenum and it will give you enough clearance. Although, when welding on the head, TAKE YOUR TIME!!! Cast Iron will crack if too much heat builds up in one spot. I would suggest just tack welding slowly alowing plenty of time for the head to cool between tacks.
Cross over tubes/ Delivery tubes. The thread end and the design of the CR Cross over tubes are different than the VP24v tubes. You will need to get the custom Cross over tubes for the CR head using VP24v p-pump conversion lines.
Pistons: The use of the CR pistons with the VP24v injectors will work and get you running. But to get the most out of your engine, I would recommend using pistons and injectors that will match up as far as spray pattern and bowl design. This is one area I haven't touched on yet as far as specs and what works the best. Maybe Smokem will chime in here and fill you guys in on the 101 of injectors and pistons.
Connecting Rods: The CR cracked cap rods in my opinion are JUNK!! Go with the 12v or VP24v rods. They have been proven to hold up in most high hp applications with just a little TLC. They are the same length as the 6.7 rods aswell. Either that or go with a set of billet rods.
Oil Pump: Not sure, but I would say a 12v or 24v helical gear pump will work and should bolt right up. If not you maybe able to just swap the gears between the 2 pumps.
Hope this helps.
Here is what I know and what he has told me.
Front gear case: it is alot simpler to just buy a gear case made for a CR/P-pump, but you can use the 12v case. Although in order to use the 12v case you will need to re drill and tap the block to get it to work. If I remember right, he told me that only 2 of the orginal holes in the 6.7 block lined up. And yes it is a ***** to do and time consuming, but it may save you alot of money in the long run.
Oil pan: correct me if I am wrong, but the CR oil pan will not bolt up to the 12v gear case up front. Not sure if the mating surfaces are the same either. I believe I have read where a few people have cut the front off the CR oil pan and grafted the front of a 12V oil pan on to it. Although, if the mating surfaces are the same, I would say all you really need to do is fill in the original front mounting holes on the pan, and re-drill the pan to bolt up to the 12v gear case.
Gearing: Just save yourself alot of $$$ and just use the 12v or VP24v gear set. The cam and crank gears are pressed on. If you are super careful, you can remove the CR crank gear using a die grinder and a cold chissel and hammer. Carefully grind a groove in the gear at the dowl pin area of the crank and crank gear leaving a little material of the gear at the crank. Be super carefull not to nick the crankshaft at all. Then take the chissel and carefully strike the gear in the groove you just ground out. The gear will then split open and with alittle elbow grease, it will come off. Another thing to try would be to grind out 2 sections of the teeth at the back of the crank gear. Both sections being 180* apart. Cut the 2 sections just big enough for a 2 finger gear puller to firmly grip the gear. Next place the gear puller on the crank and put pressure on the jack bolt. Some may come right off, then others you will have to heat the gear with a torch. The cam gear can easlily be pressed off and on using a hydriloc bottle jack press. I wouldn't recommend using the CR cam gear. It is only half the thickness of the 12v and VP24v cam gear, and it wouldn't last long in a high hp/big pump application.
Cylinder head: If using a CR head, you will have to modify the intake plenum or completly remove it and build your own plenum or individual runner intake. For those using the original intake plenum, you will need to cut a section of the plenum out to clear the Governor house on the P-7100. I believe you can weld in a patch panel on the inside of the plenum and it will give you enough clearance. Although, when welding on the head, TAKE YOUR TIME!!! Cast Iron will crack if too much heat builds up in one spot. I would suggest just tack welding slowly alowing plenty of time for the head to cool between tacks.
Cross over tubes/ Delivery tubes. The thread end and the design of the CR Cross over tubes are different than the VP24v tubes. You will need to get the custom Cross over tubes for the CR head using VP24v p-pump conversion lines.
Pistons: The use of the CR pistons with the VP24v injectors will work and get you running. But to get the most out of your engine, I would recommend using pistons and injectors that will match up as far as spray pattern and bowl design. This is one area I haven't touched on yet as far as specs and what works the best. Maybe Smokem will chime in here and fill you guys in on the 101 of injectors and pistons.
Connecting Rods: The CR cracked cap rods in my opinion are JUNK!! Go with the 12v or VP24v rods. They have been proven to hold up in most high hp applications with just a little TLC. They are the same length as the 6.7 rods aswell. Either that or go with a set of billet rods.
Oil Pump: Not sure, but I would say a 12v or 24v helical gear pump will work and should bolt right up. If not you maybe able to just swap the gears between the 2 pumps.
Hope this helps.
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