I drove the truck to work today to get some data. 10 mile stop and go both ways. So far it is looking optimistic. HEX out stays within 10* of ambient and IAT2 stay within 15* of IAT1. I had some time this afternoon where the IAT2 were actually 20* less than IAT1 (granted they were 150*). Overall coolant no longer continually gains heat so the new HEX seems to be shedding it pretty well. I hope to get some full boost runs logged over the weekend. May even hit the track tomorrow for the street legal drags.

I will say that extra 2" at the bottom proved to be a major pita for clearance. I had to clearance the bumper cap a little more for the out fitting along with taking more off the grill for the end tanks. For any one thinking of doing this for themselves, keep the HEX above the lower radiator support and save yourself a lot of hassle. In hind sight, I probably would have just made it 30x12.

 

Some pics of the final install....

Had to remove the bumper to do the lower mounts and hose routing.


Had to clearance the bumper cover for lower fitting and headlight bucket for upper fitting.


While everthing was out, decided to relocate the pump and reroute the hoses along with changing out the 1/2nptx12an fittings on the tank to 3/4nptx12an. The 1/2npt id was teh smallest of all in the system so I wanted to open them up, especially the outlet to the pump inlet.


Final assembly.

 

Nice to see this is working out for you, it looks great. I like the idea of having one hx. I'm at the same point with my tvs1900. I was just going to have one of these made locally, the 03 and up trucks look to have a little more room than you do. Although i think the 14 will take it down till the holes in the bumper. If i cut the 30 back to 28 i can run 3/4 barbs on the hx and the hoses from my pump location will fit right on. Also put both inlet and outlet on the same side. For a 28x14 with 2.25 core i was quoted 430.00

 

Well, the weekend was a bust. The track got canceled due to rain as did any other data collection drives.

However, I did have a nice conversation with a guy from BTR radiators at a Jeep event going on over the weekend. Coincidentally they make the cores for FSR, the company that fabbed my heat exchanger. More interesting is the conversation we had about the manifold mounted intercooler and the challenges associated with splitting that core horizontally for dual pass function. He said it is nearly impossible to weld the divider on the core side without creating at leak at the tubes. Along with being easier to manufacture, dividing it vertically is better for heat exchange. That helps solidify the theory I have on it.

 

Interesting. Do you have any plans to try to "fix" the issue?

Hell if youre going to go that far you may as well make more space and go to a largher IC core.

 

Not really sure at this point. It all depends on how testing goes with the new hex. It also depends on what I see with the endoscope next time I have it apart. I was shown a core almost identical to the size of my ic which had two rows of tubes. If mine actually has two rows of tubes instead of one as I originally presumed, and the divider just isn't connected to the core, there may only be a small amount of leakage. If this is the case, increasing pressure in the ic (by increasing flow) may force more down the tubes and back rather than around the divider. I am already looking into adding another CWA50 in series or changing over to a single EMP WP29 pump in that event. Either of those should bring flow up to around 7gpm and nearly double the system pressure.

 

I haven't really done much with the truck this summer other than drive it. The hex is doing its job at keeping coolant temps within 10 degrees of ambient. This really helps cruising iat but doesn't stave off drastic iat climb in boost. It does recover pretty quickly though.

I did get to the 1/8 mile drag strip back in June, which was a total cluster due to rain. First pass off the trailer was a 7.23 @ 95.9, 1.62. Temp was mid-80"s with pending rain. Soon as I turned onto the return road it started raining. That shut the track down for about 3.5hrs. I was about the third in line once they started back. First car down looses it and wrecks, delaying another 30 min. Truck in front of me was a 4wd diesel and was skating all over the track. I do my usual burnout, stage, get up to 2K on converter, nail it and I kid you not... I felt like I was sitting still. It completely obliverated the tires which is something I have yet to do with the new suspension/tire setup. So that run was a bust. Next pass is eliminations in the 7.0 class I was running and it is late at this point. This pass is nearly identical to the first pass other than an extra 2.5mph on the top end. 7.24 @ 98.5, 1.63 60'. I lost so time to put it on the trailer and head home. The class was full of mid 6sec cars sand bagging so I wasn't competitive at all.

 

I also went to a local autocross last month. (if you call 2hrs away local) The truck did ok but no match for the small cars that were there as the course was pretty tight. Started out with a 58sec run as I was just making sure I could navigate the course correctly. I whittled that down to a best run of 43sec by the end of the event. I did play with shock settings and tire pressures a little which seemed to help. I ran the event on 295/45/18 Nitto NT05 on all four corners. I also had the traction bars still installed which I felt made the rear stiffer than it needed to be and provide a little understeer on turn in. I think the biggest hindrance was the steering input required to navigate the course. A quicker ratio would make it much easier. I'll be watching Steve-O's results with the steering quickener in the column. I left trans in second the entire course for all runs. Playing back the logs, I think I could have left it in first to get a little more response out of the turns. I was fairly easy on the throttle most of the course trying not to kick the back end out.
I removed the traction bars today and will be heading to this months event tomorrow. Hopefully I can get it acting the way I want before heading to LS Fest next month.

 

Although it was hot as the devil, I made it out to AutoX on Sunday.


This months course was longer and faster with several straights and long sweeping turns so I learned alot about the truck and my driving skills
First thing, without the tractionbars, wheel hop is abundant in first gear. I tried keeping it in first and it would wheel hop just about anytime I got in the trottle. I ended up running the rest of the runs in second which helped with the hop as the converter absorbs a lot of the hit but does require more throttle on transition as it's not as responsive.
Second issues is I cannot carry any speed into a corner without the front end pushing hard. Contrary to what I have read, applying the brake on entry to transfer weight to the front actually made it understeer worse. I tried to throttle steer it thru one of the sweeping turns where it was pushing the front and got all out of shape. If I entered the turn slower and tried to gradually accelerate thru without kicking the rear out, it would eventually reach a point where it would start pushing the front.
I did not mess with the shocks any this trip but was able to play with the tire pressue go get a little better bite.


I used some window chalk to mark the edges to see how far the tire was rolling over. I had 40psi cold all around when I left the house. Hot pressure went up to 42psi after the 2hr drive up and first pass.


This was too much and finally settled on 39psi Front and 37.7psi Rear which took the wear just to the edge of the tread blocks.

 

I think I need a much stiffer front bar to keep the inside front tire planted and pull some force off the outside front tire in a turn. I have been reading up on some handling philisophies and a more modern approach is a softer spring with a stiffer bar. This allows the vehicle to pitch fore/aft on break/accel and relys on the sway bar to control roll. With a 900# spring up front it is compliant and confortable on the street so I'm not sure I want to play with the sping rates just yet.
I already have a Hotchkis 1.5" hollow rear bar so I am only looking to upgrade the front bar. Here is what I have found for options so far:

Brand Dia Rate % over stock
Stock 34mm/S 3.2107 0%
Hotchkis 1.5" /H 4.0625 21% (Discontinued, included for reference only)
Addco 1.5"/S 5.0625 57%
Hellwig 1.438"/S 4.2700 33%
Belltech 1.375"/S 3.5745 11%
Ridetech 1.438"/H 3.4975 9%

*rates were calculated assuming similar material and geometry per bar diameter only. Hollow bars assumed 0.25 wall material.

I am thinking of going with the Addco as it calculates to be the stiffest, considering the amount of understeer I am getting and the added weight up front with the supercharger.