Ya this is boiling down to why im interested in this so much, easier, probably cheaper. The only reason i was planning on an inline pump was in order to get the fuel i want. A P-pump is overkill yes, but unless we figure something out on the cat pump, or DB2 /4 it remains the only pump capable of my "goal". For those wondering, i want what NMB2 has at his crank, to my wheels. 500bhp 1000ft/lbs and that should be more than enough to break more than i could dream of.

I think the CAT pump would be a likely canidate... but i dont know what its going to take to rig it up... little hummer is BIG. I can get a running core for $200 local, however its off a NA engine.

Soo... Racin. Do you know if there is any substantial differences in the the turbo / NA Cat pumps? Also, how bad do you want to play with one?... I think i might just want to buy one, and if i do, i might just lend it to ya.

 

Booo!!!!lol

 

Like I said, if I was to mess with anything, it would be the CAT pump, not because its the highest flowing pump, but because its different, and its already setup in a V8 configuration. As far as the differences go, I have to admit, I dont know a whole lot about them, Ive read some info on the net, but thats just about it, and with that being said, there isnt a whole lot on the net about the pumps themselves. I think to really get some info on them, you would have to buy a CAT pump expert some beer and have one with him. I cant imagine the operation is that much different than an inline pump, they just oriented it in such a way to be more compact on top of a V style engine. Id be more than happy to tear into one, but preferably I would hope to spend my own money on it, that way I wouldnt feel guilty if it didnt work out, or a screwed something up. Ive already had a line on a few 3208 pumps that I have dropped the ball on, I just need to follow through when I do find one again. As far as making one to fit an IDI, regardless of working the pump internally, Im totally down for that, and it would be right down my alley...


Yeah yeah yeah... It was more if a tongue and cheek comment... But seriously, there is a point when you just HAVE to come to your senses... I am a believer (More than the vast majority out there) in the IDI, and I think it is capable (In street form) of WAY more than we have seen, its a durable setup with a few weak links that are easily cured, and as long as you can get some fuel to to it, your in good shape, the misconceptions of indirect injection arent true, at least to the levels we are looking at pushing these things. Now with that being said, There are a few fatal flaws of the IDI engine. 1) It only has 5 head bolts around a bore that is relatively large for a diesel, 6.0's blow head gaskets because of the same reason, except that there is only 4 bolts, IH solved that by increasing the bolt diameter by 4mm on the 6.4, to 18mm, and increasing the torque... The 6.9/7.3 bores are significantly larger, and the bolts have an un-even spacing, its not a complete star pattern, most dont even push their studs to where they should be for a relaible setup on these. My studs are at 150ft/lbs, and I havent blown a HG yet, and I have stock compression and an intercooled 21psi, my next engine will have the studs torqued this far as well... 2) Even though you can make some numbers with it (Other IDI's have made numbers HUGE compared to what we put out per liter), its still IDI. Most have the misconception that all the fuel is combusted in the PC and pushed into the cylinder, so the "passage" is a huge restriction is not true. The total combustable volume of air in the PC is a fraction of total displacement, that means that the rest of the fuel is pushed out of the PC and combusted with the rest of the air in the cylinder... The PC is nothing but a buffer to soften the combustion process, thats why the IDI doesnt sound as harsh as a 12v cummins, Its actually similar what the factories do to the stock injection events on the computer controlled diesels, there is a pre-injection, and main injection, and sometimes a post injection. Problem with an IDI, is on peformance tunes with a computer controlled diesel, you can totally get rid of the Pre and Post cycles and increase the total fuel delivery, you cant do that with an IDI, so your limited in your total injection event, not electronically, but mechanically. Sure you can bore out the PC's and do a bunch of work to make them flow, but its still a band aid, and its still not going to work perfectly. 3) The 6.9 has small head bolts, and the 7.3 has weak bores, neither are good for lots of fuel and boost, a sleeve job solves that on the 7.3 block, but that gets spendy to still be limited by the inherent weaknesses of the IDI design. 4) The N/A rods are the weak link of the bottom end, yes NMB2 can get away with running the stock rods, but his are ARP'd, shot peened, and cryo'd, and he only has 4.03" bore putting force on them, albeit, its impressive, and he made sure they were perfect before he put them in, who knows how long they could last at his power levels, let alone any more. The only upgrade (That isnt $2k) for rods is the factory turbo stuff, which is arguably a bit more beefy than stock forged PSD stuff, and those are rare as hell at this point. My point is, is for an IDI, a P-pump is overkill, and they are stock on an engine that can handle a lot more power than the IDI can... It would just be a no brainer (And cheaper) to build a cummins to use the fuel its stock P-pump can put out. That was my rationale behind the comment...

Im totally down to get as much fuel as we can out of a DB style pump, and to throw it at an IDI. Id love to get some respectable numbers (Beyond what is respectable for an IDI) from an IDI, and do it with a stock style setup. Im not a legit engineer, and Im no diesel expert, but there is nothing about these engines that makes them NOT capable of producing some serious numbers... There have been some pioneers of IDI performance in the past, and a few of us are tinkering around right now, but the potential of these engine have never been fully realized... Its easy to get fuel out of every diesel out there, except for the IDI, and thats its drawback. Other than that, the IDI is no less responsive to mods than any other diesel out there, computer controlled or not...

 

I only have a few issues with your post J-Nasty.....and the first one is something you already know.

I don't agree the 5 stud per cylinder is that big of a deal..... with stock bolts, and old gaskets, and a turbocharger operating @ 2:1 DP with a stock cam and restrictive stock exhaust... sure, maybe.

My old 6.9 ran studs @ 100ft lbs, and 20+psi of hot boost, worked HARD, for over 13,000 miles with no failure.

My current 6.9 is setup @ 95ft lbs, and I have run 30+psi for the last 5,000 miles, and tapped up over 40 a few times. You CAN damage gaskets by over torquing.

I just think the head gasket issue is a myth, along with the now old myth of IDI's can make more than 200hp/450tq without dumping twin turbos, nitrous, meth and lpg at them.

Secondly, to your number 4, about the stock rods. I would have to say 100% without a shadow of a doubt in my mind you're shooting much too low on the strength of the rods.

There is no doubt in my mind a stock N/A rod will handle 400rwhp. If I had to guess I would say my personal rods (which dont have ARP bolts btw) are probably suitable for 500hp, maybe more, but I wouldn't place a money bet on it just in case.... I base this off of holding stock duramax rods in my hand, which is VERY similar to the IDI rod shape/weight/size and they are rated for about 650hp.

Other than these points, I agree with everything else you have to say, spot on.

 

On the point about the rods, like Racin said the stock PSD rodsare a little bit smaller than the turbo rods and only a bit bigger than the NA rods correct? Based off the fact that a PSD rod can handle 400hp quite easily I see no reason that a NA rod can't handle 300-400hp easily. I mean your engine hit 300hp and yours are shot peened and cryo treated. I think they will last quite a while at that level. But that's just my opinion based off observation and an educated guess.

 

there is 4 different PSD's..... Considering there is only one of those rod sets comparable to our IDI rods, we should probably be more descriptive.

Specifically the 7.3 powerstroke rods. The forged units are good for around 550hp-600, the PMR's are 400 safely.

The only worthwhile advantage you get by going from an N/A rod to the turbo rod is the increase in wrist pin diameter.

However, you then lose out on the advantages of the 6.9, which if you're in a tow rig... outweigh a larger wrist pin..... because lets be honest, none of us are blowing n/a wrist pins apart.... and I am the only person pushing real boost numbers, through a charger that choking my engine non-the-less.

Just for some visuals:

7.3 PSD rods



Turbo vs N/A IDI rods:



Dmax - 6.4 - CTD

 

Justin, I know how you feel about the headbolt issue, we've had this conversation, and given the current state of IDI performance, your absolutely right... My stud torque is completely overkill for my setup, but my decks werent perfect, and I wasnt going to chance it, especially in the early days of my IDI knowledge. With that being said, my comments are directed at future gains with an IDI, making real numbers, competitive with tuned modern diesels and such. The fact is, is with huge fuel, lots of air, a 4"+ bore, an un-even bolt spacing, and 7/16" fasteners torqued to 95ft/lbs leaves a whole lot to be desired. Do we know where its limit is? No not at all, and your engine is proving that one step at a time. As far as the rods go, its the same deal. Obviously the N/A rods can tackle 300whp/600wtq, your setup has proved that, how long will they be able to, who knows, well find out...I hope its much more, because N/A rods are a dime a dozen. As far as Turbo Rod's are concerned though, I completely disagree, If you look at the N/A Rod compared to the Turbo Rod in the pic, the Beam cross-section (A common failure point) is much bigger, and the web from the beam to the bolt (Another) is also much beefier as well. The pin size isnt really a big deal, because as long as you have a beefy pin, like yours, your good structurally, the bigger pin only offers more piston pin bore support to prevent bore distortion, and thats so rare, its really a non issue. However, if you look at the PSD rods you posted, the IDI turbo rods are just as beefy in the key areas I noted, the only advantage the PSD rods have is in the extra width at the crank end, and it doesnt even look like the beam width extends that far, the Bolts are another Area of advantage, but mainly for RPM purposes....

Now on to my point... The two things I listed above, are the two biggest weaknesses of the IDI engine, and are the two things that are going to keep the IDI from reaching modern power levels... With both of those being the weak area, at some point something is going to give, its either going to be a head gasket from lifting a head, or a connecting rod is going to bend/break, its just a matter of how much power is it going to take to get there... And based off of those limits in other engines, Id say its not too far above where your at.

Here is a good read and a little bit of science to understand why the bolt patterns and torque matter so much, and why the IDI is at a disadvantage. Its not regarding engines, but the principles still apply. http://www.boltscience.com/pages/gasket.htm

 

you misunderstood me. I wasn't saying the N/A rod was as strong as the Turbo rod. I was saying the only advantage you're really going to gain is the bigger wrist pin.

You're not going to break the N/A rod. We cant make enough power, or more specifically, fuel hard enough, low enough, to break them.

You, or anyone else may disagree.... but until you break or bend a rod, it means nothing. I don't know Kens specific power levels of his older hopped up IDI, and he probably doesn't either.....but I'm guessing it was more than mine since he had equal or more fuel, and much more air... which is my current limitation.... he also spun 5,000rpm but he never bent or broke an N/A rod, however he flattened wrist pins. Yes, I have slightly thicker, and cryoed wrist pins, but they are still the weak spot I think.

Still, to remedy this issue would require you to run a 7.3, which is a downgrade in several other respects.... so I say get what you can from the 6.9, establish the limitations..... if you're not happy move on to the next platform. (not you specifically, just generally speaking)

As for the bolt pattern.... I know I'm coming off as grumpy today, and maybe I am.... but I don't give 10,000 *****s what a book or website says, or how many degree's in engineering that author holds.

First the IDI couldn't handle 12psi, then it was 15, then I started pushing 20, now I'm pushing 40.......

To say the IDI is at a disadvantage because of the head bolt pattern is kind of funny.... really the IDI is at a disadvantage in ever aspect when compared to a CTD.... so the 5 bolt pattern, decked and studded can only handle 40psi instead of 65psi.... are we really going to be upset over this?

 

Justin, you and I both know that its not about the amount of boost the heads can hold in, but the amount of cylinder pressure... And cylinder pressure equates to one thing, more power. When you or anybody else starts throwing down some numbers with an IDI, say, in the 400whp range, then we are going to see how these drawbacks cope with the increased cylinder pressures. My money is on either the Rods or the HG's...

Anyway this wasnt supposed to be a pissing match, I was just trying to illustrate that the IDI is limited compared to other diesels, and those other diesels happened to come with things like P-pumps, so I dont see a reason to go through the trouble on retrofitting a P-pump to and IDI, when even a 7.3PSD would be a better candidate for a retrofit if somebody wanted to invest the money in something like a P-pump.

I dont think there is as much disagreement here as it looks like there is ...

 

On the note of the head gasket issue, hopefully Hypermax gets those new ones that they are working on done soon. That would go a long way toward helping with that issue.

 

^ true.

there are many areas this engine could improve on. aka the reason we now have the power stroke and other much modern trucks.

the real point of hopping up an old engine is to say hey i did it and proved you wrong.

i mean hey, you could put dual ports in the precup, and speed the flame front by starting it in two points in the cylinder and that would probably help some, it all adds up.

after the edm will you be reassembling the pump? or have you worked out a way to supe up the transfer pump?

 

I will re-assemble the pump myself, its pretty straight forward. Then Ill get it on a stand, even if I have to send it to Ken to dial it in.

 

Im with both of you guys, but its kinda like NMB2 said, until you break it, cant really say its a limitation. I will agree that the headgaskets dont seem to be as big of an issue as it seemed, but still seems to me that it is a likely spot for failure. As far as rods, i have honestly never heard one one bending or breaking. For the wrist pins, i am planning on building a 7.3T with the larger pins, and having them treated. I wonder at what point the pistons will become the weakness, at least stock ones. Hypereutectics are not known for outstanding strength when compared to forged, and lets not forget they were intended for NA or at the very most low boost applications, they may be sensitive to advanced timing at higher power levels, this however is just speculation. My other curiosity is what kind of wear the engine will have after X amount of miles. Perhaps light overhauls will be more frequent, hopefully not THAT frequent, but im sure all of the extra stressors will have their toll. To say the least i would be very interested to see pics of the inside of justins engine after 50k miles.

As for why i want to hop up an IDI.. it was free so i put it in my pickup, and its staying there because its unique. If you dont think i like unique peek at my sig. Apparently nothing screams unique quite like a 400hp IDI. Also, i like to play with it and tinker... what fun is plugging in a piece of plastic and circuitboard?

But if you get a flow bench thrown together, id be willing to sponsor a ginnea pig pump for you to test and play around with if you wanted. You would be doing all the hard work anyway. Then if im lucky i might get a pump out of the deal, given compensation of course. Youre far more suited to tear it apart and go "hmm this will work best like so" if you follow me. Going to talk to the guy... well sometime, to see if me pulling it will drop the price a little and see if i can grab a few extra toys with it, like the gear and cover. One guy down there doin the job of 10 so i think he will go for it. Im really curious to see what it flows stock, and what you think can be had out of it. All i could really find on it was different ratings for the engines, from 225NA on up to 435 turbo'd, best i can tell theyre all the same (more or less) pump.

 

This is my honest, unbiased, "expert" opinion on the hypermax gaskets.

do not buy them.

Hypermax has a bad track record with gaskets in other platforms, and the non-machined fire ring design they are putting together will not last in a daily driver.

There is nothing wrong with the felpro and VR gaskets currently offered, so unless you're trying to replicate a Max Lagod IDI, those gaskets are not necessary, and will be a complete PITA.

 

I thought it was the C-ring design that wasn't good for a DD? Ron told me they weren't gonna be that design. Isn't it going to be like the design you and I have spoke about before?