Common rail heads

Bigtoy302

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Eugene, OR
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CJAA swapped Tacoma
I'm doing some research on possibly building a CJAA CR and keep hearing how the heads don't flow. I see people talking about a 180hp head that is better but I can't find any info on this. Engine code? Are they actually bigger?

I want to build a 350+hp CR for a off road project but it looks like the heads are a bottleneck. I'm not opposed to porting the stock head but just seeing if there is something better on the euro only stuff.
 

ketchupshirt88

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waupaca, WI
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is there a particular reason you want to or have to use a CR? im not sure anyone has even bothered to make 350+ HP out of a CR... but its been done by multiple ppl on VE and PD engines so the big roadblocks have been figured out on those. just food for thought.

that being said, 350HP is ALOT to ask of a TDI because of its low RPM range. do you really need all that HP for off-road or are you more looking for torque? you can definitely get 400+ ftlbs of torque while only making 200-250HP. much more than that and you may have gearbox issues anyway...
 

Bigtoy302

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Dec 20, 2016
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Eugene, OR
TDI
CJAA swapped Tacoma
is there a particular reason you want to or have to use a CR? im not sure anyone has even bothered to make 350+ HP out of a CR... but its been done by multiple ppl on VE and PD engines so the big roadblocks have been figured out on those. just food for thought.

that being said, 350HP is ALOT to ask of a TDI because of its low RPM range. do you really need all that HP for off-road or are you more looking for torque? you can definitely get 400+ ftlbs of torque while only making 200-250HP. much more than that and you may have gearbox issues anyway...
Two reasons. One the CR engines are cheap and plentiful around here and I want to see what I can make with one. I own a CNC machine/fab shop so I'm not worried about custom parts/mods.

Yes, 350hp is needed. Think 2500lb rocket!:D

Not worried about the transaxle. It will handle the torque. $$$$$

There are a few builds on here but nobody's finished them. I don't want to go as extreme as TDIsyncros build:D
 

mrchill

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The head from a passat (CKRA) is better to start off with. The head that breaths the best stock is the CUAA. That is a European passat tdi. Comes with 240 hp stock, full emissions. If I were going to go nuts with a build...I would start with that engine. There are tremendous benefits to it.
 

ketchupshirt88

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waupaca, WI
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2005 Passat daily, a bunch of others in the graveyard out back...
Two reasons. One the CR engines are cheap and plentiful around here and I want to see what I can make with one. I own a CNC machine/fab shop so I'm not worried about custom parts/mods.

Yes, 350hp is needed. Think 2500lb rocket!:D

Not worried about the transaxle. It will handle the torque. $$$$$

There are a few builds on here but nobody's finished them. I don't want to go as extreme as TDIsyncros build:D

as long as you know what you're getting into... haha

@ 2500lbs its prolly not going to be in the stock chassis... lol. So please make a build thread in the conversion section when you get a little ways into this. im lookin forward to seeing it.
 

diffas

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Lots a bs here. Sure your CR wont probably rev up to 8k, but something like 6k is nothing for tdi. Cams and valve springs needs to be upgraded and sure some porting wont hurt. Thing is to get big enough fuel pump and nozzles.
 

ketchupshirt88

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waupaca, WI
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2005 Passat daily, a bunch of others in the graveyard out back...
why BS? the engine that he is referring to as "cheap and available" in Eugene,OR has gotta be a CR140.

to make that into 350hp it would either need lots of torque or lots of rpms. 450@4k/5252=342 or 375@5K/5252=357 or 300@6K/5252=342 etc etc you guys know how to do the math...

either double the stock torque at 4k or hold onto 300ftlb all the way out to 6K.

those numbers are surely easier to get with the modern 16V DOHC engines than with my antique VE but hes still looking at 250% of the stock output and fuel is only a third of it.

you need lotsa fuel, enough air to burn it and the "millennium falcon factor" - as Han Solo says, *come on baby, hold together*
 

Bigtoy302

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Dec 20, 2016
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Eugene, OR
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CJAA swapped Tacoma
Lots a bs here. Sure your CR wont probably rev up to 8k, but something like 6k is nothing for tdi. Cams and valve springs needs to be upgraded and sure some porting wont hurt. Thing is to get big enough fuel pump and nozzles.
Yeah what bs? Here in the USA we have CR140's.
 

Bigtoy302

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Dec 20, 2016
Location
Eugene, OR
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CJAA swapped Tacoma
why BS? the engine that he is referring to as "cheap and available" in Eugene,OR has gotta be a CR140.

to make that into 350hp it would either need lots of torque or lots of rpms. 450@4k/5252=342 or 375@5K/5252=357 or 300@6K/5252=342 etc etc you guys know how to do the math...

either double the stock torque at 4k or hold onto 300ftlb all the way out to 6K.

those numbers are surely easier to get with the modern 16V DOHC engines than with my antique VE but hes still looking at 250% of the stock output and fuel is only a third of it.

you need lotsa fuel, enough air to burn it and the "millennium falcon factor" - as Han Solo says, *come on baby, hold together*
Yes, I could use another engine and make way more power way cheaper but what fun is that? I like going outside the box.

TDI's sound good. I really don't want to listen to a ecotec or K24 scream all day.:D
 

v8 coupe

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OK having recently looked into this very thing for my build which is going to TDIsyncro's level I haven't found much that doesn't require a completely different everything that we don't have lots of here in the USA.

The CJAA head has some major restrictions but those are fairly easy to solve if you aren't needing to base emissions. Issue #1 is the swirl ports, these are there simply for emissions and at higher power and those higher boost they are way too much. The simplest solution for them is to heavily port those ports (1 per cylinder) and remove a lot of the swirl port to basically make it a fill port. Issue #2 is the intake flaps in the intake. people have removed these from the intakes with fairly good results, but i am going to build a new intake completely. Removing the flaps in the intake and heavily porting swirl port will take care of the first 2 issues. The 3rd issue is the fill port not being quite big enough to really fill the cylinder well. I already had 2 sets of .5mm oversized valves with longer tips made for the CJAA heads and had my cams reground by Geoff at Colt cams so I have both of those taken care of. I also have upgraded valves and retainers to allow for slightly more RPM and to keep the valves closed at boost pressures over 50PSI.

The CKRA head and CUAA head is completely different and as such require the ECUs to go with them. The head has 2 cams similar to the CJAA heads, but each cam isn't just intake or exhaust they both control both sides. They use the cam timing to do cylinder swirl and those can't be used on the CJAA bottom ends. The engines also from what I was told have reservoirs inside the engine and valves in them to control coolant flow unlike the older CJAA engines.

There is my 2 cents on this since I am looking to go another 100HP past that 350HP you are looking to get. I fully believe this engine has that possibility as it has been done in the 16v PD engine and the CR has so much more fueling capability than that engine does. The biggest issues you are going to have is the injectors will need to be completely overhauled with bigger nozzles I suggest looking into Diesel truck places as those guys are getting into the level of HP/L you and me are shooting for. The other thing is the HPFP the CP4.1 is in no way capable of supplying enough fuel and rail pressure to do that much HP. I am still not sure on what the best option is for a different HPFP is the CUAA at 240PS uses a CP4.2 and with a stage 1 or 1+ tune is at 300PS. Pushing the CR140 past the 240whp range is going to take some serious work, but can be done.
 

diffas

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Yeah what bs? Here in the USA we have CR140's.
I was reffering to tomatoketchups claims about "low rev" range of tdi and therefore not getting power. That is bs. Like I said, some mods are required. Fueling is probably biggest problem.
 

Bigtoy302

Active member
Joined
Dec 20, 2016
Location
Eugene, OR
TDI
CJAA swapped Tacoma
OK having recently looked into this very thing for my build which is going to TDIsyncro's level I haven't found much that doesn't require a completely different everything that we don't have lots of here in the USA.
The CJAA head has some major restrictions but those are fairly easy to solve if you aren't needing to base emissions. Issue #1 is the swirl ports, these are there simply for emissions and at higher power and those higher boost they are way too much. The simplest solution for them is to heavily port those ports (1 per cylinder) and remove a lot of the swirl port to basically make it a fill port. Issue #2 is the intake flaps in the intake. people have removed these from the intakes with fairly good results, but i am going to build a new intake completely. Removing the flaps in the intake and heavily porting swirl port will take care of the first 2 issues. The 3rd issue is the fill port not being quite big enough to really fill the cylinder well. I already had 2 sets of .5mm oversized valves with longer tips made for the CJAA heads and had my cams reground by Geoff at Colt cams so I have both of those taken care of. I also have upgraded valves and retainers to allow for slightly more RPM and to keep the valves closed at boost pressures over 50PSI.
The CKRA head and CUAA head is completely different and as such require the ECUs to go with them. The head has 2 cams similar to the CJAA heads, but each cam isn't just intake or exhaust they both control both sides. They use the cam timing to do cylinder swirl and those can't be used on the CJAA bottom ends. The engines also from what I was told have reservoirs inside the engine and valves in them to control coolant flow unlike the older CJAA engines.
There is my 2 cents on this since I am looking to go another 100HP past that 350HP you are looking to get. I fully believe this engine has that possibility as it has been done in the 16v PD engine and the CR has so much more fueling capability than that engine does. The biggest issues you are going to have is the injectors will need to be completely overhauled with bigger nozzles I suggest looking into Diesel truck places as those guys are getting into the level of HP/L you and me are shooting for. The other thing is the HPFP the CP4.1 is in no way capable of supplying enough fuel and rail pressure to do that much HP. I am still not sure on what the best option is for a different HPFP is the CUAA at 240PS uses a CP4.2 and with a stage 1 or 1+ tune is at 300PS. Pushing the CR140 past the 240whp range is going to take some serious work, but can be done.

I was thinking about milling off the intake portion of the head off to get in there for better porting like they do on the Cummins heads. Then just build a new aluminum intake. Need to get a head and see if there is enough meat to tap some holes for the intake.

My plan is to put the LB7 Duramax CP3 on it. Still need to look into custom injectors/nozzles. There are lots of places that do Cummins, Powerstroke and Duramax injectors so hopefully they can do these. I currently have lots Industrial injection parts on my 12v Cummins in my Ford. Maybe they will be interested.

Are you going single turbo or compounds?

Stock pistons?

I'm guessing your upgrading the rods?:D
 

Macradiators.com

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Nov 2, 2015
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Romania
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2.0 CR 360hp
It can be done. My build is going ok, just waiting for pieces to arrive to close the engine.
What started as a 300hp build is evolving into much more, stay tuned.
BKD 16v head which flows less than your CR head does 330-350hp, 400hp on extreme builds with porting + camshafts.
Porting the cyl head is the way to start as there are many restrictions on the intake side, so plenty of room for improvement.

6000$ for 4 nozzles, they must be fookin' crazy, i can buy the entire CUA 240hp engine for 2500€, jeez
 
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turbobrick240

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maine
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Very cool to see some injector options. That's $6000 canadian, so they are practically giving them away. Kidding. That's $4500 US, still way too much.
 

Bigtoy302

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Dec 20, 2016
Location
Eugene, OR
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CJAA swapped Tacoma
Very cool to see some injector options. That's $6000 canadian, so they are practically giving them away. Kidding. That's $4500 US, still way too much.

Read their site again. They are not available yet. Still testing. I'm sure they will be priced with the others. :D
 

diffas

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Now thats what I call price! :)= There must be a typo.
 

CNGVW

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I see the intake and port entry is piss poor, I am building a new Chump TDI with a CR engine and DSG platform.
My plan is to machine the intake some how to place four tubes in there then make up a log intake to mate using silicon hose connectors. This should give a better shoot in to the head.

If I can build it to do 250HP and close to 400LB I will be very happy with that. If you can get that HP an LB all in a 2500 RPM and pull to 6000RPM on a road course there is not a car out there that can pull this package off the turn . The Beetle with only 180 HP 300LB and all done at 4000RPM ALH weighing in at 2700 LB never got passed in the turns.
The Golf should weigh in at 2300LB track weight.


I was thinking about milling off the intake portion of the head off to get in there for better porting like they do on the Cummins heads. Then just build a new aluminum intake. Need to get a head and see if there is enough meat to tap some holes for the intake.

My plan is to put the LB7 Duramax CP3 on it. Still need to look into custom injectors/nozzles. There are lots of places that do Cummins, Powerstroke and Duramax injectors so hopefully they can do these. I currently have lots Industrial injection parts on my 12v Cummins in my Ford. Maybe they will be interested.

Are you going single turbo or compounds?

Stock pistons?

I'm guessing your upgrading the rods?:D
 

Macradiators.com

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For 250 you only need the big turbo, ic and exhaust. why would you bother touching the head?
Multiple independent tunes all over europe, from 270 to 284 on stock pump
Price is ridiculous at 4500$ for 4 nozzles , you only need to spend 600 to transform your injectors in CZ..they do it if you know the right people.
 
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Bigtoy302

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Dec 20, 2016
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Eugene, OR
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CJAA swapped Tacoma
For 250 you only need the big turbo, ic and exhaust. why would you bother touching the head?
Multiple independent tunes all over europe, from 270 to 284 on stock pump
Price is ridiculous at 4500$ for 4 nozzles , you only need to spend 600 to transform your injectors in CZ..they do it if you know the right people.

They're not $4500. They just put that price on the website because they are not ready to be sold yet. They're still testing them.
 

v8 coupe

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bloomington, mn
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I was thinking about milling off the intake portion of the head off to get in there for better porting like they do on the Cummins heads. Then just build a new aluminum intake. Need to get a head and see if there is enough meat to tap some holes for the intake.

My plan is to put the LB7 Duramax CP3 on it. Still need to look into custom injectors/nozzles. There are lots of places that do Cummins, Powerstroke and Duramax injectors so hopefully they can do these. I currently have lots Industrial injection parts on my 12v Cummins in my Ford. Maybe they will be interested.

Are you going single turbo or compounds?

Stock pistons?

I'm guessing your upgrading the rods?:D
I am going compounds and since it is being used as a road course track car spool isn't really needed and to make tuning far easier I am ditching the VNT turbo setup completely and going with a pair of well known fast spooling billet turbos a pair of Borg Warner EFR turbos. The primary aka small turbo will be a 6258 with a 0.85 A/R on a tubular exhaust manifold with an external wastegate. That will be feeding into a EFR 7163 with an internal wastegate and a 0.85 A/R V-band housings located likely on the transmission side of the engine bay. The 2 of these turbos should be easily capable of producing 60-70PSI of boost pressure and enough air to produce 400-500hp.

I am not convinced the CP3 is the best option, but I am convinced the stock HPFP is not capable of doing much more than ~250whp it has issues on the stock injector nozzles at that power with maintaining adequate rail pressures. I am going with the GM LBL CP4.2 pump which stock can do ~600whp and that is at 2000bar rail pressure. I would like to try to use that to get to the 2500bar that the CUAA uses to get to it's 240PS rating. I thinking having the shortest injection event time is the key to having more HP without having issues with the valves, pistons, or injectors.

To answer your question yes I am using the stock pistons but in no way am I trying to do this on the stock rods or anything close to them. I have a set of Rostens I-beam rods ready to rock and roll in this engine. I have also ceramic coated the pistons and have a set of the old limit run of H11 tool steel head studs, but they were long so even after being shortened I am having another set made soon.
 

Bigtoy302

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Eugene, OR
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CJAA swapped Tacoma
I am going compounds and since it is being used as a road course track car spool isn't really needed and to make tuning far easier I am ditching the VNT turbo setup completely and going with a pair of well known fast spooling billet turbos a pair of Borg Warner EFR turbos. The primary aka small turbo will be a 6258 with a 0.85 A/R on a tubular exhaust manifold with an external wastegate. That will be feeding into a EFR 7163 with an internal wastegate and a 0.85 A/R V-band housings located likely on the transmission side of the engine bay. The 2 of these turbos should be easily capable of producing 60-70PSI of boost pressure and enough air to produce 400-500hp.
I am not convinced the CP3 is the best option, but I am convinced the stock HPFP is not capable of doing much more than ~250whp it has issues on the stock injector nozzles at that power with maintaining adequate rail pressures. I am going with the GM LBL CP4.2 pump which stock can do ~600whp and that is at 2000bar rail pressure. I would like to try to use that to get to the 2500bar that the CUAA uses to get to it's 240PS rating. I thinking having the shortest injection event time is the key to having more HP without having issues with the valves, pistons, or injectors.
To answer your question yes I am using the stock pistons but in no way am I trying to do this on the stock rods or anything close to them. I have a set of Rostens I-beam rods ready to rock and roll in this engine. I have also ceramic coated the pistons and have a set of the old limit run of H11 tool steel head studs, but they were long so even after being shortened I am having another set made soon.
CP3's are fine and make 500-600hp all day. Cheap also.

I like those EFR's but they are too big size wise. The are long.
 

Macradiators.com

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On Bobby's car the CP3 runs at 2400bar if i remember correctly, but the CP4.2 is also a good choice.
We have a tune on 3.0 bitdi of 440+hp and car run 11.9s , and we havent upgraded the stock pump yet with the one from BMW M55d , always CP4.2 but higher output
 

Bigtoy302

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Eugene, OR
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CJAA swapped Tacoma
Oh I am aware of that, but how do they like running at 2500bar?
I don't know. The Duramax and Cummins guys run 1800-1900bar. Is 2400-2500bar needed? I'm not sure if it's needed with a pump that can actually flow big volume.

I'm still a learing about the common rail stuff. I run a mechanical P7100 pump cummins 12v still in my tow rig:D
 

v8 coupe

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bloomington, mn
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I don't know. The Duramax and Cummins guys run 1800-1900bar. Is 2400-2500bar needed? I'm not sure if it's needed with a pump that can actually flow big volume.
I'm still a learing about the common rail stuff. I run a mechanical P7100 pump cummins 12v still in my tow rig:D
Is it needed? that's very arguable but if I understand all this stuff correctly raising the rail pressure forces more fuel threw smaller holes in less time resulting in a larger amount of fuel in a shorter time. I am using a Duramax LML CP4.2 which runs stock at 2000bar and with larger turbo and injectors these engines are doing ~600WHp before a HPFP upgrade is needed. Using the CUAA stuff will be just like the stock CP4.1 stock where only one of the pistons in the HPFP is coming to TDC for every injection event. I believe VW uses the CP4.2 on the CUAA engine to have the second piston stabilizing the rail pressure at 2400bar. I plan on having a new injection pump pulley built for it the same size as the old ALH injection pump pulley to make it the same size as the cam gear resulting in each pistons coming to TDC as alternating injection events happen.

This is only a theory now, but it should solve a few issues with cutting the pump speed in half high rpm cavitation should be reduced/eliminated and with each piton having more time to refill with fuel before it sends pressure force into the fuel rail for an injection event. If this does work awesome, but if not it'll be back to the stock CR140 setup and see how that works out. I do believe that this is the pump to use for higher HP Common Rail TDIs but the CP3 is my fall back for now.
 

Macradiators.com

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2.0 CR 360hp
It seems you just want to make things complicated when they are simple , reliable and work well already.

Pump piston and TDC events are not important in multi piston pumps. 2nd piston is always off and this would mean it has no sense, its a parasite.
Instead The entire system works as an accumulator of pressure, i'm told they teach this in mechanics university here where they study this stuff.

Also rotating the pump at half the speed just because you imagine there is a cavitation problem might not get you far.
 
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v8 coupe

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It seems you just want to make things complicated when they are simple , reliable and work well already.

Pump piston and TDC events are not important in multi piston pumps. 2nd piston is always off and this would mean it has no sense, its a parasite.
Instead The entire system works as an accumulator of pressure, i'm told they teach this in mechanics university here where they study this stuff.

Also rotating the pump at half the speed just because you imagine there is a cavitation problem might not get you far.
really they aren't important? Really because on the GM Duramax LML engine that I got this pump from it is setup so 1 of the 2 pistons was coming to TDC as an injection event happened. On the 3.0L TDI that uses a CP4.2 the pump is timed again so each piston was coming to TDC as an injection event happens. The fuel rails are not in any way large enough to store fuel at pressure between injection events. Also try not having the CP4.1 pump timed to have the piston coming to TDC on the injection event guess what the engine won't run. yes on the CP3 pumps it doesn't matter because they are 3 piston pumps not single or double piston pumps.

Yes you are probably correct I am trying to complicate things, but how many people are trying to run their TDI engine consistently at higher RPMs for long stints of time? I am sure 99% of TDI users won't ever have any HPFP high rpm cavitation issues because most might only occasionally see 4-6k RPM I am fairly sure I will see 3-6k a lot more. That is because my engine is being built to take abuse and a lot of abuse at that being a track engine. So yes for a street application the CP3 might be a great option and the CP4.1 pump with the cam and piston from the larger of the CP4.2 pumps would also probably be great, but not for my application. I am also doing quite a bit of "extra" stuff that for many is considered over kill and for a street engine it completely is. I am not trying to build a street engine so over kill is exactly what is needed to keep it from needing to be replaced every month or year.
 

Macradiators.com

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We did not time the CP4.2 on the 2.0 CR engine and runs great, as i am sure it doesnt need any timing on the B8 CUA engine.
JD eng did no timing on the CFG engine and also works great.
It doesnt matter what you think, the entire fuel system works as an accumulator of pressure (rail + fuel pipes, there is quite some volume there).

Now you got me confused. what pump do you want to use? CP4.2 is running great and havent read of failures on the V6 engine.

I've red a few threads of 300+ builds ..not one seen the finish line.
 

nate0031

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SE Ohio
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96 B4 Passat
The CP1H pump (similar to a CP3) in the Cruze diesel does not have pumping events timed to cylinder firings, and that's from the factory. The CP3 swaps on our CR140's also don't have pump events timed to cylinder firings. Both systems work just great. I agree with others on here, a CP3 is very reliable, cheap, easily modded, and more than capable of supplying the fuel you need. Now that there's a bolt on kit for our engines, that'd be the way I'd go hands down.

Really interested in seeing what a CJAA with a CP3 and big turbo can do. Also curious about the head flow concerns.
 
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