Worlds Fastest Comanche

The 3.0 and 3.2L Volvo inline 6 motors used on the XC70 (US Model name) seem like great engines. Either one has more hp than a stock 4.0 and the torbocharged 3.0 is about 300 hp. The problen in the US is that Volvo parts are very expensive in wrecking yards (junk yards), not much is know about the ECM and how to rewire or reprogram it for an different vehicle. The transmission bolt pattern is not known either, if a bellhousing exists or a adapter plate is made by sombody it would be great. I did find 2 motors in junk yards, A turbo motor for $2,500 and a non turbo motor with 56,000 miles for $2,600. The chevy Atlas 4200 (290hp) can be had for about $800 in junkyards. I would assume that in norway that US car parts go for a priemum. I did have an interest in the Volvo 3.0 for my land speed Comanche, they have a 3.0L class and this seemed like a good canidate to run in the blown class. I did not persue it because i could not find any information on a RWD transmission that would bolt up or if a ASIN bellhousing was avaiable

Well seing how you are the " Self-appointed President for Life of the International MJ Preservation Society" your opinion may be somewhat biased. AN empty MJ is really not that heavy , i suspect some where in the 3,400 lb range. (2wd, which is what i have) I think the weight is similar to the HHR which comes standard with a Ecotec. The Cobalt is probably around 2,800lbs, but put a couple of fat people in ti and you could get close to the weight of an MJ. I think I am going to give it a try, the Ecotec gets 35mpg highway in a Cobalt, if i get anything over 25 in an MJ i would be happy. The Ecotec probably will not last 250,000 miles, but i can't remember the last vehicle i owned for 250,000 miles. The stated goals are better gas mileage and more power.

Here is a HP curve for a 2.5 looks like about 130 ft/lbs wouls be the generally available torque The ecotec would have about 160 ft/lbs and the atlas 175-185ft/lbs. I think the Canyon was geared more for gas mileage than for performance. I am not sure what my rear end gear ratio is, but i think it is a 4.10. a ratio like this or shorter would put the engine mor in to the power band. As i said at the start, i could rebuild the 4, or put in a 6, but i can find Ecotec engines with 60,000-70,000 miles on them for $450-$500. Even a boneyard 2.5 seems to be $800- $1,000 At $500 per engine the ecotecs are almost disposable.

I have a Mj with a blown up 4 cylinder, and was thinking about using it for a daily driver. Its a 5 speed. I was looking at my options, rebuild the 4 banger for $1,200-$1,500, swap in a 4.0 which would probably cost me the same or more. because it is a driver, one of the main concerns is fuel economy. I would be willing to spend more on the engine swap and make up fir the additional cost be the increased fuel economy. SO i started looking for an engine that had more hp than my existing 4 banger, got better fuel economy and was really cheap in the boneyards. My first canidate was an ecotec, several versions avaiable, generally the 2.4L was rated around 170 hp and 162 ft/lbs of torque, so more hp the he jeep motor, a little more torque, but no match for the 200 ft/lbs of the 4.0 Probably would be great on gas and a 260hp version is available they used in the Cobalt SS. So i could put a stock motor in to start , the put a turbo motor in later. Canidate #2 is the Colorodo 4 banger, either the 2.8 or 2.9 180 hp on the 2.9, close to the stock 4.0 in hp A little more torque than the Ecotec, but no turbo version available. The cool thing is that is it is the smallest menber of the GM Atlas family , so a 5 and 6 cylinder are available. here is a curve on the 5 banger. More hp than a stock 4.0 and probably better mileage. The colorodo uses a asin trans so the bellhousing might bolt up, the only other hurdle would be a custom harness for the ECM .

We will be taking the Bonneville comanche to the Great Lakes Dragway tomorrow night (September 29th) http://www.greatlakesdragaway.com/ 25 bucks to run your truck down the track, ladies free (let your girlfriend drive your truck?) Lets have a Pow Wow !!

Actually Scott was at the track on wednesday the 15th, so you guys missed it. He may go back next week. He ran 1a 13.2 110mph with a 3.08 rear.

I will be working at The Machine tool show in Chicago next week, if anybody is headed that way Stop by the Toyoda Machinery booth and ask for me. Also we will be taking the Comanche to great lakes dragway on Wednesday next week, come by and see it live! I will not be there because of the show, but My son Scott will.

Good Point, you can probably get similar results by extending the roof line, putting a bulkhead halfway back in the bed, to create a swirl behind the cab, then taper from the bulkhead to the rear of the bed floor, remove the tail gate.

A true representative of the Comanche Club. Make sure your sticker is still visible with the cover on.

I'm not back in Utah anytime soon, but i believe the Utah timing assoc. has an event in September and the SCTA has the world finals the end of October. Check out their websites for the schedules. We plan to be back next august, but the budget looks pretty tight right now. so we will have to see

It is a competition, and in this case I am competing against a guy who has a block and heads that were designed to be used in a Nascar Series. Tough competition. My son and I learned a tremendous amount. It is not just about the engine, you need to build a reliable race car. On our car everything worked, we did not blow anything up, we did not spin out or flip over, we had good traction. All we needed was some more HP. We know what gears to use next time, and about how much HP we need to break the record. Right now I am out of money (probably like most of us these days). I did contact 505 performance and asked if i could borrow the "insane inline II" turbo motor (690hp) to try a run in the Comanche. No answer on that yet, but maybe the people on the board could help. How about writing an email to sales@505performance.com and tell Zach that you would like to see what his motor would actually do in a vehicle. Let's see if it would actually hold up on a 5 mile run on the Bonneville salt flats . We will be back next year, and we will bring home the record.

I was looking around the internet today an came across an article on the SRT10 where it holds the worlds record for the worlds fastest production pickup @ 154.587 We went over 155 with 6 cylinders not 10, just to give you some perspective.

I was reading about the design of the Cobra hardtop, the rear of the car is kind of flat, but the shape creates a bubble that acts like a tapered surface, The same idea could be applied to Pickups, we just need an expert in aerodynamics to design it,

You broke the code, 100% correct. Somthing could probably also be done with vortex generators near the rear of the roof

Look around the internet, you can actually get worse gas miliage with the tailgate removed.

You may think I am in the wrong place to talk about areodynamics, our trucks are built like bricks. But if we could get them a little more areodynamic, maybe we could save some gas. One thing i learned at Bonneville is that the most areodynamic bed cover is half a bed cover. A cover that starts in the middle of the bed and goes towards the rear. It needs to have a verticle bulkhead from the floor to the cover. This design was used on the 1990 GMC Syclone. It came from extensive testing in the GM wind tunnel. I have been trying to find out the Drag Coeifecient of my Comanche, i found a published number for a 91 Cherokee, it was .45 The Frontal area was 25.84 ft/sq or 2.4 m/sq. i don't know if drag would be the same for a Comanche. I asume the frontal area would be the same. Maybe we can help each other out here. I found a excel program that lets you calculate the Cd (drag Coeificent) and rolling resistance of a car, you can find the spreasheet and procedure here http://www.instructables.com/id/Measure-the-drag-coefficient-of-your-car/ It would be interisting to get numbers for stock comanches, lifted, different tires etc. It would give us a good idea what changes we can make to save gas, and what changes not to make that will cause a large change in either Cd or rolling resistance. It would be good the do the test before making changes, then after the change to see if you made things better or worse.

Lee has been very helpfull and suportive, he did the dyno runs for free. I did have to pay for the cylinder head and the additional modifacations. I have never asked for anything for free and nobody has offered. Wait, Rustys Off road gave me some suspension parts. but that is about it. You have to realize that the 4.0 is out of production, and the market for parts for it is shrinking every year. If i was in the jeep business, i think i would focus on the new Chrysler V6 they will be putting into the wrangler and Grands. Maybe I'm off base, Indy cylinder heads still makes aftermarket blocks for the AMC v8s, and that motor has been out of production since 1991. I don't think the AMC stuff is the main part of their business, they also produce Chrysler blocks. The market for very high performance parts for the jeep engine is limited. Most people just want more power out of their daily driver. I would be happy to have any sponssorship, doing all this out of my back pocket is very expensive.

A turbo would put me in a different class, and would probably get me over 200mph. It's about going fast and having fun. The blown class record is currently open, so anything we ran would become the record.

I already have the Hesco head and it has been ported and the intake and exhaust port matched. The intake flows about 274 cfm and the exhaust about 170 cfm. An airflow Reasearch SBC head can flow 330cfm on the intake and exhaust in the 230 range. So the intake can flow 25% more and the exhaust 35 percent more. If i had 25% more hp, i would be in the 560 hp range. ( a nice place to be). I managed to get 1/3 of a aluminum cylinder head from Lee at Heaco. It's really just a piece of scrap, but i can make modifications to it and test the flows. better than making modifacations to a $2,000 cylinder head. We will be back at Bonneville next year. I would like to keep the jeep engine in the comanche, I did talk about building the 4 cylinder, many of the parts could be reused. A turbo is possible as well, we will just have to see how it all works out.

we did make it to Bonneville, we did 4 runs, the best was 155 mph and change. We did not have the right gear . the altitude and the rolling resistance of the salt really hurt the performance. The air density was aroulf the 7,000 ft level. with a gear change we would probably run 165 or so, but the record is at 173. The guy who owns it rund a bored and stroked chevy 4.3 with Brodix heads and intake. The heads just flow so much better than a jeep head. I do have some work to do before next year. I did send an Email to 505 performance asking if i could borrow their 690 hp turbo motor that was written up in JP magazine. We will have to see if that goes anywhere. The good news is that now i can actually say that i have the worlds fastest production Comanche. The Lakeview Curiser is faster, but it has a chevy V8 in it and therefore it is no longer considered a production truck. The great news is that the truck performed flawlessly, everything worked as it should, we didn't break anything. A few more HP was all we really needed.

I wanted to get some pictures of the Bonneville truck next to a stock height truck so people can see how much we have dropped the truck. My guess we are down 9" or so. we dropped the axle 4" , the tires are 22" diameter, stock is 28" so 3" due to the smaller tires. then we have different springs, so another 1-2" there. so 8-9" seems to be it. So if you may be around the woodstock Il area on Saturday with a stock height truck, it would be great!. PM me if you might be able to come. Thanks

I don't have any pics of it going down the track, I am in the push truck, so the car is way down the track before i can be in position to take a picture. Maybe next time i go to Maxton a club member can come by and take some pictures. Here are some i have

The brakes are not dragging, just way too much energy going into them. I will shift more load to the rear and toy the forzen rotors, we will see what happens.

We were having a little trouble witht he front end shaking wnen we were coming down from 127mph. We pulled the wheels and found the drivers side rotor had 2 cracks in it and was blue. I ran out to the local Autozone and was amazed that they actually had a couple in stock. Made a couple of runs with the new rotors and they turned blue as well. I did crank in the proportioing valve all the way in, The factory valve under the pickup bed is long gone, i just have a ss brakes unit with a knob for adjustment. The adjustment was set in the middle to start, so turning it all the way in should shift more load to the rear brakes. The front tires are only 22.5" diameter, so at 150mph the front wheels are turning at about 2250 rpm, the reeas have 25.4" tires and would be going about 2000 rpm at the same ground speed. The rear tires are larger and wider, so they can exert more force on the brakes than the front, so i may be better off putting the proporting valve on the front rather thasn the rear. I do have the metric ton option. Lee from Hesco suggested that if we just got rid of the front brakes all the problem will go away. Just use rears. Dragsters don't have front brakes. I think for not i will just pick up some cross drilled and slotted rotors on ebay, and just the chute over 125

We went to the Maxton Mile on the weekend of June 26-27 2010. we made 5 runs, the best was 147.5, but Scott was on the brakes going through the lights. It was a license run and we could not exceed 150mph.