Modify 7.3 idi vs cummins swap

IDIBRONCO

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I'll probably just do bolt ons. Are a set of arp head studs all that's needed to handle the power.
At the 350 HP level, all you need is the studs. Since you're only going to the bolt on mods, then forget about the cam, piston shaving, and other things like this. If your valves weren't hitting pistons before, then you'll be fine now. You won't even need to check the clearances.
 

IDIBRONCO

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I have nothing solid to base this on, but I'd guess that it would be similar to a 350HP Cummins.
 

Thewespaul

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A few in that range, an auto truck made 410/800 at the wheels, with a stick you'll definitely be in the 800ft lbs range with a 130 pump and 3582.
 

CBRF3

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The stock injectors will work at these power levels. Generally, a good turbo will be way more beneficial than a cam change. As for the shaved pistons, it's kind of up to you. If you are going to tear the engine completely apart, then it wouldn't hurt to have .010" removed, but it isn't a have to do thing as long as your valve clearances are within spec. If you're just going to do add ons, then there is no way that you could have the pistons shaved. If you go as far as to remove the pistons for shaving, then it would be best to have the block bored and start fresh with new pistons and bores. Is it required? No, but since you have the engine this far apart, you may as well get the longest life possible out of it. Of course, if you are going to run a bigger cam, then the pistons may need to be milled or you could buy decompressed pistons. All decomp pistons are is pistons that have the wrist pin bore made closer to the top of the piston which makes the piston sit farther down from the head.



I feel there is a bit of iffy info here the shaved pistons or decompression pistons its kinda upto you is false once you go 15psi boost even with headstuds and modified powerstroke rods you need to decompress otherwise you will have a bad day towing hauling heavy and you blow a head gasket if plan to run 15psi boost decompress the motor otherwise your asking for issues and intercool it regardless for any boost above 8+PSI ish your valves will thank you and your power will actually be there 6-8psi intercooled will run like 15psi non intercooled and if you got 15psi and are not intercooled your losing massive amounts of power just throwing it away due to heat a engine wants cool air to breath not cooking hot 15psi non intercooled is 150f+ often around 200f or more a engine loses massive amounts of efficiency above 135f for intake charge air temps.

I will also tell you a good cam will really liven these motors up especially down low aka where the turbo is just coming on before it has hit typ4's torgue cam really from all info I have found is the good one for towing was designed for loggers running NA but typ4 swears its awesome with a turbo as has many others the R&D idi cam is more for top end power aka higher rpm once turbo has already hit the better you can get our engines to breathe exhaust and intake and the shorter can run the intake tubing hince why I run a air to water intercooler with at best 3.5 foot of full 4 inch tubing I am running a custom HX40 turbo and man when it comes on its set to kill its interesting I am still working on my setup my motor is insanely modified glow plug delete decompressed in many ways down to around 18:1 and I run 20-25 psi of boost as for power number last time i tested was about 325hp and 680ftlb of torgue and that was without really pushing it was around 3/4 throttle or less I am sure I had more there but I played it safe as its my tow pig and often daily driver.

I run the rare marine injection pump on my truck sadly cannot get it rebuilt by anyone its a special unit very hard to find ( DB2831-5090 1819681c91 1993-1994 marine 260BHP )

I have been doing my own motors and work for years and have found what works best for me and I tow alot a whole lot literally daily with my old IDI's yes a cummins 12v has more power but also the upkeep is much more expensive and also I find the fuel mileage ( run alot of alternative fuels waste veggie used motor oil trans fluid and such ) i get with my IDI and reliability and simplicity out weighs what the cummins brings to table indirect injected are less finicky simple as that also there are companies that make forged pistons that fit our idi's the factory cast pistons are junk in my eyes also I got a company that made me a set of steal top pistons it was pricey and was a pain to get balanced out properly at machine shop but they are running in my tow pig and its got almost 1 million miles on that motor now after over 10yrs of running it and only in past 6 months did I start getting blowby.

My motor is a 7.3 idi sleeved to a 6.9 and studded with glowplugs deleted intake heater added from a powerstroke or duramax in the original hole the CDR was in and i run 6.9 flame cups in the heads steal topped custom pistons with tight gapped piston rings both 1st and 2nd compression rings from hastings and modified power stroke 7.3 rods propane injection and water methanol injection along with much more but the list would be huge so will stop there.
 
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Daniel McCurdy

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how exactly does the cummins have a higher upkeep expense. In terms of reliability the cummins is just as if not more reliable than the idi. For simplicity the cummins in the ford seems to be easier to work on. Deleting the glow plugs would make the idi a lot simpler how did you go about doing that and how well does the intake heater work in cold weather
 

CBRF3

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I have been doing my own motors and work for years and have found what works best for me and I tow alot a whole lot literally daily with my old IDI's yes a cummins 12v has more power but also the upkeep is much more expensive and also I find the fuel mileage ( run alot of alternative fuels waste veggie used motor oil trans fluid and such ) i get with my IDI and reliability and simplicity out weighs what the cummins brings to table indirect injected are less finicky
how exactly does the cummins have a higher upkeep expense. In terms of reliability the cummins is just as if not more reliable than the idi. For simplicity the cummins in the ford seems to be easier to work on. Deleting the glow plugs would make the idi a lot simpler how did you go about doing that and how well does the intake heater work in cold weather


run waste motor oil or waste veggie thru it and find out direct injecteds dont play well with it add to it the cummins 12v is more expensive maintenanace wise and is much more complicated price a stock injection pump for a cummins 12v price a stock injection pump for our idi's price the injectors for a cummins 12v then factor in because ours have a lower pop pressure and run a single stream with a large single port we can easily rebuild our injectors multiple times without ever having to buy any parts not even the copper crush seals heat them up red drop in hot water theyre soft again and able to reseal our old IDI's are normally NA not turbo so again cheaper to maintain price any of the main failure parts like head gaskets and such for the cummins 12v vs our IDI's I buy my head gaskets for like $25 a piece so for a head gaskets set $50 for the felpro's new again our old IDI's are cheaper to maintain and much more simpler that is mathematical facts.
example of our head gasket price https://www.amazon.com/Fel-Pro-9047-PT-Cylinder-Gasket/dp/B000C2AFLA/ref=sr_1_4?dchild=1&keywords=head+gasket&pd_rd_r=d58f71ea-4c65-46df-b496-fd6838ca24c5&pd_rd_w=O5Onr&pd_rd_wg=pg8h4&pf_rd_p=bec88bc8-d41e-4895-a8dc-a35e165b8995&pf_rd_r=DS2QT67626H6KARAFSEV&pid=Z1Ow8nd&qid=1606178905&sr=1-4&vehicle=1993-54-669-656-47-31-11-7-3499---2-801--&vehicleName=1993+Ford+F-350

I cut the glowplug portion off then simply drove the guts out the connector end then tigged them shut and put in a lathe to make a perfect seal again and used a intake heater out of a powerstroke 7.3 or LLY duramax in the CDR hole yeah in cold weather is hard to start unless is plugged in but you simply give it a small shot of propane ( got propane injection and methanol injection ) and crank and it fires and extreme cold you use starting fluid and after it fires you then run intake heater for a about 30 seconds and then motor will smooth out ( our flame cups in head heat up fast ) and let it idle on high idle I have custom steal topped pistons with a 12 thousands higher wrist pin to decompress the motor and also the removal of the glow plugs reduces compression.

I found the 6.9 idi fire cups get the fuel mix out into the cylinder quicker than the 7.3 fire cups making it run better decompressed also with the 6.9 fire cups i get benefit of thicker throats so less worry of cracking and because i am decompressed at level I am I can add alot more fuel and boost as for the intake I modded it heavily cut the cross section out and welded a 45 degree 4inch aluminum boost elbow into the intake and run with no CDR at all and inject the blowby directly into my exhaust system via my custom dual 4inch exhaust log stack system.

the key thing with our motors is flow in and out even our turbo selection and such makes a world of difference I made custom split up pipes flanges and used 7.3 powerstroke uppipes to a custom T4 flange and mounted my twin scroll custom liquid cooled billet wheeled 10 blade turbine wheel HX40 look up turbo labs HX40 super mine is very close to that http://turbolabofamerica.com/holset-hx40-super-40-turbo-specs/
I did a HX 50 once but that thing would take a while to spool but when it came on it was like someone lit dynamite under the truck the thing would go from calm to uncontrolably sliding sideways and well leaving dually burnouts I played with that for a while and well after 2 rear difs I decided to go back to the custom HX40 as it came on more safely and with less o crap here we go.

I have a crankcase pressure gauge installed along with fuel pressure gauge directly on my pillar so can monitor these I run dual carter fuel pumps and have modified my entire fuel line assembly and run a 80 gallon fuel tank on my flatbed 1/2 fuel line splits to 2x 3/8 fuel lines feeding my pumps where they leave the pumps and merge back to 1/2 inch I run 1/2 inch all the way to injection pump I removed factory filter assembly and run a custom filter setup under the bed directly under the tank directly after the fuel pumps and have a large 100micron strainer setup in front of my fuel pumps my injection pump is also modified I run a custom fitting arrangement the main fitting on back of pump is modified to almost 1/2 inch where it goes to a 10an 90 radius bent then to my fuel pressure gauge port again full 1/2 inch flow entire way thru past my pumps I never dip under 6psi 90%+ of time is almost 10PSI and my injection pump flows a crap ton of fuel my injectors are modified to 1950PSI pop pressure and i made custom injector nozzles for my truck that flow a ton of fuel in a straight stream to bottom of the flame cup where its vapored by the heat of the cup not by the injector ( a big difference of ours vs a Cummins 12v ).

My fuel tank on flatbed is high enough as long as is over 1/2 full I can gravity feed in a pinch as long as dont push it hard and will not go negative on fuel pressure done it a few times when had a issue with electrical system.
 
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Farmer Rock

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run waste motor oil or waste veggie thru it and find out direct injecteds dont play well with it add to it the cummins 12v is more expensive maintenanace wise and is much more complicated price a stock injection pump for a cummins 12v price a stock injection pump for our idi's price the injectors for a cummins 12v then factor in because ours have a lower pop pressure and run a single stream with a large single port we can easily rebuild our injectors multiple times without ever having to buy any parts not even the copper crush seals heat them up red drop in hot water theyre soft again and able to reseal our old IDI's are normally NA not turbo so again cheaper to maintain price any of the main failure parts like head gaskets and such for the cummins 12v vs our IDI's I buy my head gaskets for like $25 a piece so for a head gaskets set $50 for the felpro's new again our old IDI's are cheaper to maintain and much more simpler that is mathematical facts.
example of our head gasket price https://www.amazon.com/Fel-Pro-9047-PT-Cylinder-Gasket/dp/B000C2AFLA/ref=sr_1_4?dchild=1&keywords=head+gasket&pd_rd_r=d58f71ea-4c65-46df-b496-fd6838ca24c5&pd_rd_w=O5Onr&pd_rd_wg=pg8h4&pf_rd_p=bec88bc8-d41e-4895-a8dc-a35e165b8995&pf_rd_r=DS2QT67626H6KARAFSEV&pid=Z1Ow8nd&qid=1606178905&sr=1-4&vehicle=1993-54-669-656-47-31-11-7-3499---2-801--&vehicleName=1993+Ford+F-350

I cut the glowplug portion off then simply drove the guts out the connector end then tigged them shut and put in a lathe to make a perfect seal again and used a intake heater out of a powerstroke 7.3 or LLY duramax in the CDR hole yeah in cold weather is hard to start unless is plugged in but you simply give it a small shot of propane ( got propane injection and methanol injection ) and crank and it fires and extreme cold you use starting fluid and after it fires you then run intake heater for a about 30 seconds and then motor will smooth out ( our flame cups in head heat up fast ) and let it idle on high idle I have custom steal topped pistons with a 12 thousands higher wrist pin to decompress the motor and also the removal of the glow plugs reduces compression.

I found the 6.9 idi fire cups get the fuel mix out into the cylinder quicker than the 7.3 fire cups making it run better decompressed also with the 6.9 fire cups i get benefit of thicker throats so less worry of cracking and because i am decompressed at level I am I can add alot more fuel and boost as for the intake I modded it heavily cut the cross section out and welded a 45 degree 4inch aluminum boost elbow into the intake and run with no CDR at all and inject the blowby directly into my exhaust system via my custom dual 4inch exhaust log stack system.

the key thing with our motors is flow in and out even our turbo selection and such makes a world of difference I made custom split up pipes flanges and used 7.3 powerstroke uppipes to a custom T4 flange and mounted my twin scroll custom liquid cooled billet wheeled 10 blade turbine wheel HX40 look up turbo labs HX40 super mine is very close to that http://turbolabofamerica.com/holset-hx40-super-40-turbo-specs/
I did a HX 50 once but that thing would take a while to spool but when it came on it was like someone lit dynamite under the truck the thing would go from calm to uncontrolably sliding sideways and well leaving dually burnouts I played with that for a while and well after 2 rear difs I decided to go back to the custom HX40 as it came on more safely and with less o crap here we go.

I have a crankcase pressure gauge installed along with fuel pressure gauge directly on my pillar so can monitor these I run dual carter fuel pumps and have modified my entire fuel line assembly and run a 80 gallon fuel tank on my flatbed 1/2 fuel line splits to 2x 3/8 fuel lines feeding my pumps where they leave the pumps and merge back to 1/2 inch I run 1/2 inch all the way to injection pump I removed factory filter assembly and run a custom filter setup under the bed directly under the tank directly after the fuel pumps and have a large 100micron strainer setup in front of my fuel pumps my injection pump is also modified I run a custom fitting arrangement the main fitting on back of pump is modified to almost 1/2 inch where it goes to a 10an 90 radius bent then to my fuel pressure gauge port again full 1/2 inch flow entire way thru past my pumps I never dip under 6psi 90%+ of time is almost 10PSI and my injection pump flows a crap ton of fuel my injectors are modified to 1950PSI pop pressure and i made custom injector nozzles for my truck that flow a ton of fuel in a straight stream to bottom of the flame cup where its vapored by the heat of the cup not by the injector ( a big difference of ours vs a Cummins 12v ).

My fuel tank on flatbed is high enough as long as is over 1/2 full I can gravity feed in a pinch as long as dont push it hard and will not go negative on fuel pressure done it a few times when had a issue with electrical system.

What are the benefits of deleting the GP's.I understand they can be a pain,but why not just wire them manually?That's what I did on both my trucks,and I haven't looked back

Rock
 

CBRF3

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What are the benefits of deleting the GP's.I understand they can be a pain,but why not just wire them manually?That's what I did on both my trucks,and I haven't looked back

Rock

The issue I have found is when you add alot of fuel / boost even with a manual glowplug setup they melt and destroy motors I lost 3 motors due to this with beru / motorcraft factory glowplugs i thought same thing till I started upping the fuel / boost and had it happen a few times pull them out to find nothing was left of them even if didnt use them facts are they run nearly red hot while engine is running due to combustion my experience is they melt and fragment and little metal pieces go into your cylinder while are boosting hard and fueling it next thing you know a few weeks or days later or even minutes later you have a damaged cylinder / piston these will wedge between piston and cylinder wall and gouge them or embed into piston and cause a hot spot as many call it that will eventually blow thru the piston usually at worst possible time LOL on a large hill loaded heavy in my experience both times the third i had no idea of damage till disassembled motor and found the pieces wedged in piston still ran pretty good just had alot of blowby can you guess why.

if are not going excessive you are okay as long as you keep a eye on things and watch your EGT's carefully these motors last a longtime and oil changes / maintenance are crucial is how one of my highly modified high output tow pig IDI's has survived almost 1 million miles without rebuild it now has way to much blowby so am swapping the motor out soon and puting a low mileage engine in till i get this one rebuilt and freshened up to my standards.
 
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u2slow

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run waste motor oil or waste veggie thru it and find out direct injecteds dont play well with it add to it the cummins 12v is more expensive maintenanace wise and is much more complicated price a stock injection pump for a cummins 12v price a stock injection pump for our idi's price the injectors for a cummins 12v then factor in because ours have a lower pop pressure and run a single stream with a large single port we can easily rebuild our injectors multiple times without ever having to buy any parts not even the copper crush seals heat them up red drop in hot water theyre soft again and able to reseal our old IDI's are normally NA not turbo so again cheaper to maintain price any of the main failure parts like head gaskets and such for the cummins 12v vs our IDI's I buy my head gaskets for like $25 a piece so for a head gaskets set $50 for the felpro's new again our old IDI's are cheaper to maintain and much more simpler that is mathematical facts.

I run wmo on my 6BTs. No injection pump failures on 4 running trucks owned by me the last 5-10 years. Bought used performance injectors because I wanted. Still have not *needed* any. No head gasket failures to date. Copper washers are reusable (within reason) on all sorts of applications. Injector tips are consumables. A better injection pump costs a little more. I'll suck that up.

Some guys are very OCD about cummins-only parts on their cummins. That drives up maint costs for sure.

Now the IDI has two heads, two head gaskets, more oil per change, single-mass-flywheel conversion costs... gets spendy on the starting side with GPs, controllers, dying batteries, dying starters. A mechanical 6BT starts briskly year-round for me without grids (one stock battery).

I've spent my time with IDIs and 7.3PSDs. 6BTs are cheaper for me to run... 10 years going now. No question. More power too (every one is turbocharged).
 
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