Sell my 7.3 idi or keep it

Hey guys after much considering and a lot of hard work I'm thinking of selling my 1990 f250 4x4 7.3 idi. I bought a 28ft travel trailer with a super slide thinking the truck would be able to handle it. But after going 65 then a slight hill comes up it slows down to 35 or slower. If i start on a hill it takes me awhile to get it up to speed. I know you can turbo it but I don't think I could get it where it would keep up with traffic. So I'm considering buying a 6.4 powerstroke but would like to keep 7.3 if it could tow as well as I like. I understand the idi isn't a power house but I have a steep grade coming up here in 3 weekends that I have too pull the trailer up and with a four wheeler in the bed I don't think it will make it up without overheating on me. Sorry for the long post but I'm on a short time frame here. And need advice on what I can do with the truck or if I should sell it and buy the 6.4 egts on my truck towing just the trailer on flat ground at 65 is about 800 degrees and the coolant temp get up pretty fast

First off, any 6.4 purchase is a mistake imo.

Let’s see what we can do with the idi, those egts aren’t bad. Have you timed the truck? How old is the fuel system? What rear gear and trans do you have?

Thewespaul said:

First off, any 6.4 purchase is a mistake imo.

Let’s see what we can do with the idi, those egts aren’t bad. Have you timed the truck? How old is the fuel system? What rear gear and trans do you have?

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Yes I dropped it off a local shop to have them do it cause they had the equipment still. The fuel system is only a year old r and d injectors and injection pump and the trans is zf5 and 4.10 gears.

You should be doing better than 35 with that setup. How much does the camper weigh? Do you know what they set your timing at? Where were your coolant temps?

Thewespaul said:

You should be doing better than 35 with that setup. How much does the camper weigh? Do you know what they set your timing at? Where were your coolant temps?

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The cam per tag fully loaded is 8500 pounds and I have the paper somewhere if I can find it. And about 220 on flat ground almost 230. It's all new cooling system.

Okay, take a jumper wire and place it between the two prongs on the top of the injection pump. This will turn on the cold advance solenoid with the ignition. You will have 1-2* more advance, and slightly more fuel output. This will tell you if the pump needs advancing yet or not depending on if it runs better or worse.

i don't see the mention of a turbo.
park the IDI behind the house. you'll need it when the 6.4 breaks.
buy 7.3 psd, 6.0 psd or 6.7 psd. But whatever you do, stay the heck away from the 6.4

Yup, no turbo = no power. 180 crank HP isn't much, especially when loaded.
Add 80+ to that with a turbo and more fuel... it'll help a *lot*.

Macrobb said:

Yup, no turbo = no power. 180 crank HP isn't much, especially when loaded.
Add 80+ to that with a turbo and more fuel... it'll help a *lot*.

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I've never understood how people can expect a naturally aspirated motor can keep up with a computerized, turbocharged and intercooled motor. Simple means a little slower.....well ok, alot slower. Treat the motor to a turbo and a intercooler, now things are happening

If your price range is good enough to buy a 6.4 then buy a low mileage 6.0 and delete, stud (not necessary but opens a lot of doors) and then tune in the extra 25 HP to bring it to 6.4 levels, or find a 7.3 PSD and do some power upgrades and mods to bring it into the modern era. I love my 6.0, at 300k original engine. My buddy’s 6.4 is on its third at 220k.

Back to the IDI, the truck in my profile pic pulling the dead dodge diesel, it’s a 6.9 and wouldn’t pull an enclosed 12’ motorcycle trailer at 65. Then I turbocharged it with a used banks kit and it pulled that dodge 300 miles on the interstate doing70 no issues, slowed to 55 on steep grades. Put into perspective the dodge is 7500 LBS trailer is 7k and the idi is 7k last I weighed it. 21500 lbs total.

Sorry for the long post, just my .02

towcat said:

I've never understood how people can expect a naturally aspirated motor can keep up with a computerized, turbocharged and intercooled motor. Simple means a little slower.....well ok, alot slower. Treat the motor to a turbo and a intercooler, now things are happening

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A properly running na motor should pull that weight better than 35 was my point. Start with the cheaper fixes like timing adjustments and possibly some filters, because you spend the big bucks to put on a turbo and intercooler on a sick idi and you’ll end up with some disappointing results.

If you want one that will "keep up with traffic" I'd say you're better off getting something a little newer.

I personally love the simplicity of these older ones. I know they're a little slower and I'm ok with that. It IS a truck after all, and you are hauling some weight and have some wind resistance.

I have every intention of putting a Turbo on mine when I can afford it, but let me clue you in on the condition of my truck when I got it....

When I bought my truck it could barely get out of it's own way. So bad that I would have been surprised if I could have gotten up to 30mph with a lawnmower on a trailer behind it. Timing was fully retarded, and the fuel filter was partially plugged among other things. I played with timing until it felt pretty good and popped a new filter on it. My timing is now FULLY ADVANCED as in there's no more room to advance it and when we got a meter on it it was at 9.3 degrees which is pretty darn close to spec (which tells me my pump & injectors are probably pretty tired). I'm not sure how much play there is in the timing but I'm guessing I was somewhere around 1-2 degrees when I got it. HUGE difference. Now I can haul a 5000# car on a trailer without issue unless I want to hold 60mph on hills and this is NA.

My point being @Thewespaul is absolutely correct. Make sure it's RIGHT before deciding if you want to ditch it. My truck was MISERABLE before and now except for being loaded right down I love it. Not bad at all for a 30 year old truck with 200k miles on it.

I'll second the above. For the amount of money it takes to buy a new truck, let alone repair it, I invested 2k into some goodies and now my truck doesn't know when a trailer is even hooked up.

Thewespaul said:

A properly running na motor should pull that weight better than 35 was my point. Start with the cheaper fixes like timing adjustments and possibly some filters, because you spend the big bucks to put on a turbo and intercooler on a sick idi and you’ll end up with some disappointing results.

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I did the air filter last weekend and changed the oil and fuel filter is probably about 6 months old but I change them every 6 months so it will get a new one. What about a fuel pump? It move when you put it to the floor. I know there is electric and the mechanical ones also but any brands that are better then the other?

Id change the fuel filter and buy a cheap fuel pressure gauge so you can verify you have enough fuel supply pressure.