The next step in performance?

[Govt issue]

I know I am betting this subject to death, but I belive that people like kennedy or others with heavily modifed trucks could benifit. Cylinder head flow and cam profiles. Back to basic hotroding.There has to be a point that boost increases and power dosent increase at that same rate. Say the difference between 7 psi and 12 psi is 50 ft tq. but the difference between 15 psi and 20 psi is only 15 ft lbs of tq. Not accurate figures but a valid point. The only way to over come this in my eyes is not pack in more boost but update the camshaft profiles and get some real cylinder head flow numbers on the heads to try and improve on it. If you can make it proform under vacume then it should do well under psi. The camshaft profile is awful on these motors. This will take people much smarter than me. But from reading the post there are people very capable of this. Ronnie joe and others! I would sign up to help in the research and funding as much as I could afford. I bet you could get alot of Donations from the subcribers for the development of a camshaft. My truck is bone stock. If need be, me or anyone else would give our truck for dyno testing ; base, then install and retest for gains.

[gmctd]

You really should spend some time over on the Banks Diesel website, in their Diesel Faqs and Theory section, written by CJ Baker, iirc.

You may be surprised to learn -

you cannot hotrod a Diesel in the same manner as a gasser

you cannot hotrod an indirect injection Diesel in the same manner as a direct injection Diesel

Fer instance - where you gonna get vacuum in Diesel intake tract - no throttle plate to create such an event - so how can you tune it to run with vacuum?

Surf on over and see what an old roundy-round gasser expert has to say about Diesel performance, and how to get there.

[Peter J. Bierman]

There is a different cam available made to perform better with turbo applications.
The Diesel depot develloped this cam and there are a few members running them.
I have one waiting to go in on the next engine stripdown.
Have not looked at it closly so can't tell the differance yet.

For the head porting: less restriction is allways better with or without boost, but a diesel will not react that much on it as a gasser will, specialy with boost pushing the air in.
But it helps if you look for the last HP that are in there :D

Peter

[grape]

i had 3 different cams cut to try on the dyno. However, they are far from drop in stuff, different pushrods, valve springs, and valve pockets in the pistons are required.

[More Power]

Peninsular Diesel has a single turbo 340 and a twin turbo 400. Both run with a DB4 mechanical (4-plunger pump), 18:1 pistons and a stock cam. smile.gif

MP

[TurboDiverArt]

Originally posted by Peter J. Bierman:
For the head porting: less restriction is allways better with or without boost, but a diesel will not react that much on it as a gasser will, specialy with boost pushing the air in.

Peter This I'm not understanding. All internal combustion engines to my knowledge are air pumps. The more air you can pump in and out the more power you can produce. I race turbo cars (gassers) and head porting makes a huge difference. I run heavily ported Indy heads, others with almost identical engines run an aftermarket head (cheaper). My heads have larger valves and much bigger and smoother intake and exhaust ports and I run much faster at the same boost level. It is possible I guess that at lower RPM

[AndyL]

Originally posted by grape:
i had 3 different cams cut to try on the dyno. However, they are far from drop in stuff, different pushrods, valve springs, and valve pockets in the pistons are required. What were the results?

[Billman]

Waiting for Grape's humorous answer...

[grape]

I'll let peninsular's old dyno sheets do their talking for them :rolleyes: same with the 4 plunger 8 cylinder arangement for a DB series pump. Mine still isn't together........ :( but the chassis is rolling again as of last night, now all i have to do is put the whole truck together :D

[Govt issue]

Thanks for the input. Im going to read the info on banks web site today. I do have one question. What is the biggest diference in the 6.6 and 6.5? In my eyes it is the heads and cam. If we want our 6.5 to perform like a 6.6 then we need to flow one of those heads and see how far out we are. There are guys porting cumins heads all over the place. You see I am an old street racer, who has retired. from raceing that is. Because of my small budget, i looked for ways that were uncommon to be competive. It worked very well for me. I took a stock 72 429 and ran a 6.77 8th mile in a fox body. AZ rebuild kit with a marine cam 7.91 comp. 175 shot of nitrous. had less than 2000 dollars in the whole thing. My freinds had more than that in there heads. Some of them I outran. It wasn't the fastest car on the track, but the most cost effective. I think that someone needs to break out of the box. use their own theroy instead of someone elses. This post is not intended to be an arguement. I say these thing in the best of heart to further the growth of the 6.5 performance. Thank you for your post.

[Billman]

Disappointed Grape...


Govt - You took the easy way out with the Nitrous. Pretty muched doubled the HP feeding it a bottle.

The 6.5 isn't as easy.

Re-Read the first reply to your post.

Follow said instructions...

[gmctd]

Here's a hint -

what is vacuum?

what means stoichiometric ratio?

Sorry - that's two, but that's the way I am....... ;)

[rjschoolcraft]

gmctd,

I think you mis-read his first post...

The reference to vacuum was that if porting works in gas engines being fed by vacuum, why wouldn't it work in blown applications? I don't think he ever implied anything about vacuum in diesels.

As for my position, there may be something to be gained from a better cam, but it is not worth going after until you've done a lot of other things first. It will not be accomplished in the same manner as in gas engines, though.

[Govt issue]

Banks is doing it.
Heads and Valvetrain:

The extraction of the maximum intake and exhaust efficiency will occur without compromising the structural integrity of the aluminum cylinder heads. Extensive flow testing has been performed to determine what could and could not be done to the port configurations and valves. Smaller, lighter and shorter lifters now run in bronze guide sleeves. New Banks-spec studs will replace the head bolts and main cap bolts. Unique stainless steel sealing rings will also be tested to seal the aluminum cylinder heads to the block.

To generate greater power requires enhanced airflow and fuel delivery to the engine. Banks chose to wait for General Motors newly designed 2004-1/2-version LLY heads to have a better overall head design to develop. The new heads feature superior injectors, with easier access, from outside the valve covers. Banks has ported the new LLY cylinder heads for over 30 percent more intake flow and over 50 percent more exhaust flow than stock. Used are custom stainless steel intake and larger-diameter inconel stainless exhaust valves. Stock intake valves are 33mm and stock exhaust valves are 31mm - both valves are now 33mm. In addition, custom Manganese bronze self-lubricating valve guides and tungsten carbide alloy valve seats to conduct as much heat away from the surface of the valves as possible. To match the cylinder head flow, a custom intake manifold is being designed and fabricated at Banks.

Duramax Heads and Valvetrain Overview:

[Govt issue]

That was copied from the banks website.

[grape]

the problem with the aftermarket cams being sold now is they are regrinds without welding. This means they can only make an existing bump smaller, kinda like extrude hone.......it makes an ugly port a bigger, ugly port, with really no change. Diesels have some strange burning characteristics that most would think are odd coming from hot rod gas stuff, at least I do, the 6.2-6.5 is a low rpm engine but the cam is ground on a 110 lobe sep. A powerstroke has a 104 lobe sep. That kind of lobe sep on a gas engine won't even get close to getting through inspection here in texas. Hell, our 8800 rpm small block stuff is in the 106-108 range. The duration on the intake side will help but not on the same center line because it will bleed still burning exhaust gasses out too early, the cams being sold have the same profile before and after centerline. If you're going to increase duration you have to do it on one side of the centerline.........in other words a different lobe sep.

[CareyWeber]

Originally posted by Govt issue:
Thanks for the input. Im going to read the info on banks web site today. I do have one question. What is the biggest diference in the 6.6 and 6.5? In my eyes it is the heads and cam. If we want our 6.5 to perform like a 6.6 then we need to flow one of those heads and see how far out we are. There are guys porting cumins heads all over the place. You see I am an old street racer, who has retired. from raceing that is. Because of my small budget, i looked for ways that were uncommon to be competive. It worked very well for me. I took a stock 72 429 and ran a 6.77 8th mile in a fox body. AZ rebuild kit with a marine cam 7.91 comp. 175 shot of nitrous. had less than 2000 dollars in the whole thing. My freinds had more than that in there heads. Some of them I outran. It wasn't the fastest car on the track, but the most cost effective. I think that someone needs to break out of the box. use their own theroy instead of someone elses. This post is not intended to be an arguement. I say these thing in the best of heart to further the growth of the 6.5 performance. Thank you for your post. Two things:
Indirect injection vs Direct injection
Block strength

I think all the other differences are much less important that these two..............

Carey

[gmctd]

Thanks, rj, but I got it - I was heading for Baro vs pressure Boosted above Baro.

'sides, iirc, flow benches 'draw' thru the head ports, to simulate Baro flowing into the lower pressure in the cylinder.

Here, it boils down to rpm 1700 to 3500max street, avg 2250 towing - how do you 'tune' for max power bandwidth just off idle?

Can be done in a Diesel, folks - try that with a gasser.

Cummins and Isuzu\DM, with 22000psi super tech pilot injection, can build power up into gasser racing rpm regions - flow-enhanced heads will be advantageous up there even with 60psi Boost levels. (Don't try that with a 6.5.......)

Don't get me wrong - headwork may not hurt the 6.5, but where's the return at 2250rpm cross-country?

Simpler to reflash for fuel, improve flow by cooling the charge-air and opening the exhaust, improve engine coolant scheme.

Shoot for 18:1cr, increase Boost some more withouit exceeding stock 22.5:1 cylinder pressures = more power.

Main difference is - Dielsel fuel is injected into a cylinder already chock full of O2.

Gasser's can only hope that the fuel mixed in with the incoming air charge doesn't precipitate out as it tries to navigate the sharp bends and corners in the rough intake passages on its way to the cylinder.

It is a fairly desperate quest, to keep that mixture at the 14:1 stoichiometric ratio required to make power - particularly up around 7000rpm.

Ha! Diesels laugh at yer stoichiometric ratios.

Polish yer ports.

Tune yer pipes.

Grind yer cams.

Let's see ya pull this over the Rockies at 7000rpm, bunkie........

Sorry, sorry - my 'alter' keeps assumin' control.

Point is - thinking outside the box is good, but knowing what's inside the box is most important in applying specific methods to make more power.

IMO

[Govt issue]

I will be gone this weekend so this will be my last post before monday. Is your position that the stock cam profile is the best profile that can be ground for below 3500 rpm. I don't know myself. That is the reason for the post. But I never intended for the 6.5 to exceed 3500 rpm. just thought that there was room for improvement over the stock parts. Why did the dmax go with more valves, better flow? If you un cork the intake and the exhaust systems why not the heads. Also I understand that on a stock truck these should be the last modifications. But for you highly modified guys, Where do you go from here. Grape seems to have the most insight on what cam profiles might be possible. Maybe he needs to be the one to develope a profile that can use stock parts, that will help modified rigs. The market is there listen to all the people who have bought a cam. What about the ramp? Is it as aggressive as it can be? Let me know what you think and I will reply Monday. All in Good Heart.