table of contents
The OBS Powerstroke trucks only need a few basic bolts on to make a noticeable improvement in drivability, but if you’re looking to make enough to keep up with new trucks, you’re going to want to go a bit further. Making usable horsepower means more than just tuning and an intake. An electric fuel system conversion, turbocharger upgrade, larger injectors, and an intercooler are all must haves if you want to make 400-500 horsepower like a brand new Alumiduty Ford truck does.
As many of you Ford faithful’s already know, the 1994-1997 7.3L Power Stroke was never equipped with an intercooler, Ford just opted to go with a really large 1.15 a/r exhaust housing on the stock turbocharger to help combat high EGT’s, but even in a bone stock application that left something to be desired. A smaller exhaust housing could be installed to help with the lag, but that will just compound the EGT problems by increasing drive pressure and restricting exhaust flow. The only logical step would be cooling that intake charge and increasing the air density making its way into the cylinders.
As one of the first companies to really start toying with turbochargers on diesels, Banks Power was also one of the first to understand the importance of intercooling. While the turbocharger is used to compress the air, compressing it also heats the air, making it less efficient. An intercooler is used to remove that heat, but they need to do it without blocking airflow to your radiator, so you aren’t dealing with overheating. The Banks Technicooler kit for the 1994-1997 Power Stroke was developed to do all those things and allow you to use the power you already have, without worry of pegging a pyrometer gauge on every grade you try to tackle.
The Banks kit is well engineered and will fit like a factory unit would’ve had Ford been keen enough to install one on this OBS truck. The factory core support will need to be modified to allow the new boost tubes to pass through to the intercooler that is mounted directly behind the grille where it will get the best airflow across the core. You can plan on this installation taking the better part of a weekend with the right tools, but rest assured, it’s worth it.
Results
The data collected before and after the intercooler installation were strong enough that we’d suggest this being your first priority as a 1994-1997 7.3L owner wanting to use your truck for towing. If you plan to do nothing else with your OBS Ford, plan on doing an Intercooler kit, the drop in EGT’s and increase in usable powerband is that impressive. Before installing the intercooler kit, we made some data logs on an Edge Insight CTS3 monitor while towing a 10,400lb fifth wheel trailer over a long torturous 6% grade just outside of Salt Lake City, UT. This grade has been known to kill many of trucks in the hot summer months and maintaining 65mph is tough on even brand new trucks while towing heavy. Forgetting about the speed limit and focusing on nothing but the EGT gauge that was almost impossible to keep under 1350-degrees, we ran the last two miles of the grade clear down in 2nd gear running just 37mph.
We towed the same trailer over the same grade, with no changes except the Banks intercooler kit and couldn’t believe the improvement. With the charge air coming out of the turbo and colling off before entering the cylinder heads, we had so much more throttle to play with. This trip, we were able to pull 3rd gear the entire grade at 59mph at a much more manageable 1250-degrees. That was over 20mph increase in speed at 100-degree cooler temps, towing the same load over the same grade. The is still only making around 300-hp, but with the help of the intercooler we can actually use that horsepower, where non-intercooled, we had to really feather the throttle to keep EGT’s in check. By maintaining a more constant throttle input, RPMs were easier to hold, which kept the boost where it needed to be, and our engine oil and coolant temperatures were kept a little more under control as well.
While the intercooler does take some investment in both your time and money, if you plan to increase horsepower in that 7.3L Power Stroke and have any intentions of towing, it’s worth every penny and bead of sweat invested into the job.
1 – Since the 1994-1997 7.3L Power Stroke was never intercooled from the factory, you’re really limited to how much power you can use when towing. The factory or even an upgraded turbo works okay without one, but you’ll soon find that EGT’s run hot, and you’ll be limited to how much throttle you’ll be able to use safely. Consider the complete intercooler kit from Banks Power your next ‘must have’ mod.
2 – Besides the intercooler itself, one of the key pieces to the Banks system is this unique Twin Ram intake manifold that offers smooth airflow passages for the cooled charged air to enter the cylinder heads. The Twin Ram installs directly on top of the engine and is strapped into place ensuring you’ll have no issues with it leaking or blowing out of the heads under heavy load.
3 – To start the installation, you’ve obviously got to make room behind that grille for the new cooler. Removing the factory headlights, grille shell, support piece and bumper will give you the required access to the core support area.
4 – Since our truck has an automatic transmission, the factory transmission cooler will need to be relocated. But Banks is prepared for that and included new mounting brackets in a location that won’t require you to change transmission lines. It’ll be a mess free relocation.
5 – The most daunting part of this job is knowing you’ll have to cut up the core support area to make somewhere for the charge air tubes to pass through. Banks engineers are on top of things and supply super user friendly templates to show you exactly where you’ll need to mark and cut.
6 – Using the templates as a reference, we were able to draw out some rough cut lines with a permanent marker. Obviously, you’ll want to make sure to tuck the transmission lines out of the way and be sure you’re not going to cut into anything you don’t want to behind your cut lines in the core support.
7 – We found that a couple of sharp blades and the battery powered Sawzall was the easiest option for us to use to get these areas cut out, but an angle grinder could cover this task too. The edges were cleaned up a bit and some paint was applied once we knew we had the right clearance around the intercooler inlet/outlet.
8 - The intercooler kit came with all the brackets and hardware you’d need. These brackets are for the lower mounts of the intercooler. Supplied rubber grommets are installed on the lower mount posts of the intercooler and inserted into the oval holes so the intercooler will have some adjustment side to side for the proper fit.
9 – With the lower mount posts sitting in their brackets, the supplied upper mounts are loosely installed, and the new core can be centered where it needs to be to ensure the inlet and outlets have the right clearance around the core support. Make sure there will be room to get the charge air silicone boots and clamps on. At this point, you can see how much fresh air will be passing through that core to cool down your charge temps.
10 – When reassembling the front end of the truck, the only other real modifications required is some trimming to the grille support. The plastic will need to be trimmed some to make clearance around the cast end tanks of the intercooler.
11 - With the intercooler mounted, it’s time to move on to installing the Twin Ram intake manifold and the boost tubes to run from the compressor outlet to the intercooler inlet and from the intercooler outlet to the engine. The factory intake manifold will be removed and tossed in the garbage where it belongs.
12 – Before installing the Twin Ram intake, checkout these little 2” billet machined rings from Riffraff Diesel that can be inserted into to the factory intake plenums to eliminate the plenum from distorting or crushing and creating boost leaks.
13 – The factory tin plenums aren’t known for being the strongest pieces. While you wouldn’t think the factory worm gear clamps could be tightened enough to warp that plenum, you can see this one has already been deformed a bit at some point. Since we’ll be upgrading to a better high torque t-clamp, we wanted to be sure the plenums would seal without issue, so the billet plenum insert is an easy remedy.
14 – The billet machined sleeve can just be slid right down inside the plenum inlet and the machined groove around the upper edge can be bottomed out, so you know it’s in place. Obviously, if your plenums are distorted at all, you’ll need to take care to get these inserted and get that plenum back into the original round shape. But once installed, we can torque those boots and clamp down much tighter for a leak free seal.
15 – The Twin Ram intake can then be installed into the plenum boots and the t-bolts clamps torqued down. The new turbo outlet elbow is also installed and loosely clamped into place. Banks includes a new O-ring to seal these two mating flanges, and you’ll also notice the 1/8” NPT bung Banks includes on the elbow for an easy boost reference port. It will need to be plugged off if not used for a boost gauge.
16 – While the boost tubes came powder coated in red from Banks, we opted to have a local shop reshoot them in textured black that we think makes it all look a little more factory under the hood. Obviously, that’s a personal preference, but you can see how good these pipes fit with plenty of clearance around all the other engine pieces.
