Milking as much out of my 6.9 n/a as I can

[lkc2cool]

So here is my idea I want to build the most powerful n/a diesel I can. I figure that if I do that then when I do add a turbo (when the money allows) then I will have a platform that is ready to pin my ears back in a most terrible way. I am looking for add on parts like cam heads and head porting and milling. I most definitely will add the ARP head studs assuming that the 7.3L IDI stud size is the same being as that is all I can find I am also thinking of milling the heads down a little to bring up my compression just enough to push those head studs a little and make cold starts easier being as I live in ND and it gets down to -30 up here. If that is a bad idea please stop me. I was thinking of a port and polish job also but heard that this would have little to no effect being as our motors don't rev high enough to make much of a difference in this regard. I am planning on a type4 cam and maybe some aluminum internals to lighten the rotating mass but I cant find any to speak of so i am probably just gonna balance what is there as best I can to make this motor last a little longer. I am going to treat this build just like you would a gas engine build up the compression and up the power then add fuel till you think your gonna flood it to death. But by all means if I am heading in the wrong direction would anyone here please shake me to my senses.

And with that may I send out a prayer to the great Diesel Gods,

 

[IDIoit]

welcome to the forum.
the first thing id like to introduce you to is the search button.
it works flawlessly!
i suggest you read ALL of the tech articles.
it will address most of what you posted.
head studs from the 6.9 and the 7.3 are not the same.
lots of information here about changing compression.
these engines are not gassers.
horse power is how fast you hit the wall
torque is how far the wall moves when you hit it.
using light weight materials on an engine rotating assembly does nothing but increase RPM and reduce torque.
these are diesels. we have them because of the torque.

in other words. lest just stop right here, and get you some knowledge about the basics of these engines before you go any further.
good luck with your truck.

FYI there are many many of these exact threads on here... most dont get too far.

 

[franklin2]

I would not mill the heads for higher compression, that will limit the boost you can run when you put a turbo on it. People who build a maxed out turbo engine actually try to lower the compression so they can run more boost. But like you mentioned, it can make it harder to start.

With a turbo, porting is also less important. The air is being forced under pressure into the intake and heads, so porting has less of an affect on performance.

ARP makes a kit for the 6.9, the head bolts are smaller than in the 7.3, so they sell a lot of stud kits for boosted 6.9's.

Building a turbo engine or a N/A engine will set you in two totally different paths from the beginning. And the turbo engine will not run that great until you add the turbo.

Welcome to the forum.

 

[Clb]

Its been talked about before... The answer came in the form of the stroke.
But read up in tech.
Ther was a member way back that swore he could wring out huge power and get +20 mpg's said he would prove it' that was over 2 yrs ago( that thread is full of crickets) but you can get a big grin out of these just do some homework. But also look into the gas vs diesel volumetric efficency issue before setting your path.

 

[chris142]

The compression is already 21-1 and you can't mill much off the heads before the valves hit the pistons.better off spending money on the proper turbo,intercooler, injectors and a pump.

 

[lkc2cool]

Thanks guys and yeah i have noticed that the search button is awesome around here. I understand that a turbo is king but it is really time consuming to fab it all up in a way that lasts and doesn't leak oil or exaust everywhere. I am gonna post pics of my build and keep goin n/a mostly just for the odd factor and for fun i only gave $2000 for the whole truck so some playing around with the old tow truck can't hurt

 

[IDIoit]

085, 088, and 093 COMPLETE kits can be had for under 6-700 bucks for a used kit.
no fab work, just some time researching, finding parts, and bolting it on.

the only fab work i had to do was a custom down pipe and exhaust.
any muffler shop can do this for you
it took me about 2 hours for a complete exhaust system.
sure, my OEM up pipes leak, but for around 4-500 dollars, you can buy the updated castings for a leak free connection.
typ4, a member here sells them.

not a bad idea to get a new fuel system, either.
i just did this on my truck, and man, it made a world of difference.

 

[stealth13777]

Blueprint the motor, balance the rotating mass, people talk highly about the cam. That's the base start to truly get the bottom end up to *****. Machine work may cost you but that's how to really get the most out of N/A. If you want to go that route, guys on here have done it.

But understand what these are. Diesel, not gas. Most people are going for torque and ability to move stuff, not horsepower and speed. Full injection system is next on the list, use the known good sellers you see on here. There is lots of info on here about what to, and not to, do to the heads. Look at all that and decide what is worth it to you. Do not try to raise compression. The tolerances on these motors are really close and stack up quickly; your valves and pistons won't take much to touch. A well functioning glow plug system is all you should need for cold starts.

As far as the valve train, I have seen an upgraded rocker arm on here, not sure if it's worth it over the new style.

Buy the ARP studs for your specific motor. They make them.

Turbo kits aren't hard to come by and there are plenty of bolt-on and go options that do not require fab work. You can buy new or used. Banks, hypermax, ats to name a few (some still produced new some not).


Sent from my iPhone using Tapatalk

 

[chris142]

You can spend a ton of cash on your engine and it will never run like a stock one with a turbo does.

 

[IDIoit]

As far as the valve train, I have seen an upgraded rocker arm on here, not sure if it's worth it over the new style.

those Harland Sharpes are a MUST!!!!


id have to admit, with a 3400 RPM redline,
those rockers will not give you power you will ever feel.

but your valve guides will love you long time.

 

[Black dawg]

It would be interesting to see what an NA idi with a custom ground cam and added compression ratio would run like.

The biggest thing you can do cheaply, is good exhaust...duals or single with a good Y pipe. Crank up fuel rate to acceptable smoke/egt levels. I have had a few with this treatment, that towed pretty good, even at altitude.

 

[riotwarrior]

Down the road again....here we go down that road again....looking back I seen it all here before ....oh why are going down that road again?????


Sung to Willie Nelson On the road again...

S E A R C H is your friend here....read tons, this will provide you a fantastic basis to which you will be informed and be able to understand these engines and how the function and that milling FLAT heads won't really bump compression ratio as there is no combustion chamber...it would be minimal bump due to loss of volume around the valves...I mean MINUTE change...

Good luck...Cam, porting, pump, and exhaust system are key to good runner NA engine along with a proper blue print and balance but really that's about it.


JM2CW

 

[Giddy-Up]

I'll let the more experienced comment about the power ideas, but as far as the cold starting you won't have any issue with the factory compression. The only time I've had problems is when I had battery/glow plug issues, and I'd go out of my way to start it on the coldest days. So where in this great state are you? Any pics of the truck?

 

[lkc2cool]

@ Giddy-up williston and yeah i got picks but I am working so i wi post.picks on sund ay.

 

[crashnzuk]

Good luck...Cam, porting, pump, and exhaust system are key to good runner NA engine along with a proper blue print and balance but really that's about it.


JM2CW

Just to expand on this ^, I think a set of headers would really benefit an N/A engine. The drivers side manifold is quite restrictive. Port work, cam, fresh fuel system, and headers would probably be about as good as an N/A can get.

Travis..