I DO!!
Especially curious about the suspension bits.
It is awesome, and I'm now shopping for a Cherokee.
1) It ran on MegaSquirt engine management.
2) It had an 8.8" Ford axle out back, springs flipped under for lowering.
3) The front was lowered but kept reasonable geometry. They told me how they did it, but I fail at remembering.
4) They finished the paint on Thursday night.
5) They started the turbo installation on Friday night.
6) They finished the turbo installation on Saturday afternoon.
7) It won the Editor's Choice award, so look for the whole story in an upcoming issue.
on Friday night I recorded about 22 min of the turbo install. here is the link for the video, its kinda birthing but here you go http://www.justin.tv/condorspeedshop/b/271111183
This must be Psuedosport,and his friends. Were they from Massachusetts? I know he mentioned something about a 2wd Jeep Cherokee they were putting together for the challenge. I think I spotted him in the quick look at the video I got before my computer here at work crapped out.
My bad. Sorry I thought Psuedosport had mentioned a Jeep to me when I met him a while back. To be thruthful my head was spinning with all the cool Miata stuff he had laying around,and the work we had loading up a BMW he sold to me friend that had no front suspension on it. It had become one with the earth as well,so things weren't going easy.
In reply to EvanB:
pretty sure they do still have a beam front axle. so as long as you can keep the thing located under cornering, you have no camber change with body roll, consistent alignment under brake dive and acceleration, little to no bump steer, and you can set the ride height as high or low as you want without doing wierd things to the roll centers
I understand that they cut and welded the front bar to acheive about 2.5 degrees camber on each wheel. There were a few other tricks I dont quite remember. I voted them challengers choice.
Thanks for transporting the tires down south for me, and saving shipping for Eugene.
The Jeep looked nice, I wish we had time to chat on the side of the rd in CT.
per Silverfleet:
Team External Combustion consists of WiblerM3 (Dave), Miatame (Jeff), Ma$$hole (Rob), Pseudosport (Greg), our friend who isn't on here yet (Pat), and myself (Tony). We had the token red Miata and of course, the now-famous Jeep Cherokee.
Im curious about the suspension mostly..
and following that, id like to know what went wrong with the turbo setup to run 15.5? a stock 4.0/5pd cherokee on slicks can do that.. and no disrespect to their fantastic efforts btw.
Vigo wrote: per Silverfleet:Team External Combustion consists of WiblerM3 (Dave), Miatame (Jeff), Ma$$hole (Rob), Pseudosport (Greg), our friend who isn't on here yet (Pat), and myself (Tony). We had the token red Miata and of course, the now-famous Jeep Cherokee.Im curious about the suspension mostly.. and following that, id like to know what went wrong with the turbo setup to run 15.5? a stock 4.0/5pd cherokee on slicks can do that.. and no disrespect to their fantastic efforts btw.
The stock wastegate on the turbo was 15lbs which was way too much boost for the undersized injectors they had. They had to crank the wastegate rod open and just bleed off boost to prevent from running super lean. We should all be excited to see this thing come back next year.
DirtE30 wrote:Vigo wrote: per Silverfleet:The stock wastegate on the turbo was 15lbs which was way too much boost for the undersized injectors they had. They had to crank the wastegate rod open and just bleed off boost to prevent from running super lean. We should all be excited to see this thing come back next year.Team External Combustion consists of WiblerM3 (Dave), Miatame (Jeff), Ma$$hole (Rob), Pseudosport (Greg), our friend who isn't on here yet (Pat), and myself (Tony). We had the token red Miata and of course, the now-famous Jeep Cherokee.Im curious about the suspension mostly.. and following that, id like to know what went wrong with the turbo setup to run 15.5? a stock 4.0/5pd cherokee on slicks can do that.. and no disrespect to their fantastic efforts btw.
yea, our 15.5 run was a little more than half throttle with the wastegate disconnected in an attempt to minimize boost as much as possible just so we could get a time slip to turn in. jeff (miatame) was driving and said it felt great at low rpm with boost coming on pretty quickly even without WOT.
unfortunately after looking at the roughly 30 seconds of tuning before trying to make a pass greg (pseudosport) determined that a little before 4k rpm we were already at 100% duty cycle with the undersized injectors we had to use (somewhere between 2am, beer, and 1:30 the next day we managed to lose one of our bigger injectors leaving 5...) and at WOT it went lean and backfired blowing the turbo plumbing off. not to mention that we only had the one wastegate actuator of unknown pressure that we remembered to toss into the truck before leaving for florida. turns out it was a lot higher than we could tune for.
i'm just super happy we got it running at all with the turbo and didnt blow it up so we can now go and sort things out
i'm about to pass out, just got home, but i'd be happy to put together some sort of a build thread with whatever pics we happened to remember to take during the transformation.
Strizzo wrote: In reply to EvanB: pretty sure they do still have a beam front axle. so as long as you can keep the thing located under cornering, you have no camber change with body roll, consistent alignment under brake dive and acceleration, little to no bump steer, and you can set the ride height as high or low as you want without doing wierd things to the roll centers
We used one under an altered wheelbase mustang. We figured that the aforementioned qualities would make it ideal for something that may drop back on to 4 wheels during a drag run. We never put enough engine in it to lift the front wheels, but it drive well with all 4 wheels on the ground.
Finishing the thing as the rest of the field makes runs, and then testing the new combo absolutely fresh, takes some cojones, kid! Good job it ran at all, and extra good that it hung together. Please polish this and have it for next go 'round, hey?
That sounds only a little more disfunctional than my $2009 drag efforts so i understand.
Thanks for the reply..
Still cant wait to hear about the suspension.
I'm glad to see everyone like the jeep. Thanks again to everyone who helped out. I wish I had more time to check out other people vehicles at the challenge but we were a little busy with the Miata being a pos and the whole turbo jeep thing.
The jeep was mainly Jeff and Dave's idea. Almost everyone on our team has had a Jeep at some point so it was an engine and drivetrain we knew well. The 8.8 ford swap was a popular offroading mod but we were after the 3.73 gears, rear disc brakes and limited slip. Back springs were 2 sagging Cherokee packs added together and mounted under the axle. Front was made up of I think cut f-150 springs and the bent solid axle with 2.5 degrees of camber per side. Control arm mounts were modified to keep the arms as close to factory angles as possible. Track bar mount was relocated to keep the axle centered. I'm sure once Jeff and Dave make a build thread they can give you more detail and some pics.
I was more involved with the turbo setup and Megasquirt. The Cherokees use an engine computer and transmission computer. We ran MS as a stand alone and shared inputs with the trans computer so that the transmission would shift and stay happy. One issue we had was the jeep uses the computer as the voltage regulator. Since we removed it we had to get an alternator and bracket from a 87-90 Cherokee which used a GM one wire setup.
Originally we were going to do twin turbos. We started to fab up pipes for 2 DSM t25's but all the flanges, pipes, adapters, feed lines, etc were going to add up fast plus we were running out of time. We were going to hold off on the turbo idea but 2 weeks before the event we decided to try mounting one big turbo. I noticed the older Renix 4.0 manifold was just a log with an outlet at the end. We found one and Dave cut the runners shorter and relocated #6 so we had a better placement for the turbo. I Looking at a few compressor maps I picked a 50 trim T3T4 since it looks to be the most efficient at low boost on the 4.0L That and they are pretty cheap on ebay. Anyway turbo and flange took there sweet time to show up and we got them a day or 2 before we had to leave for the challenge. Dave got the flange welded to the manifold with a piece of basket ball hoop. We didn't have a wastegate flange so we welded a 90 degree pipe to the wastegate and added an 02 bung and called it good. Thats all we had sorted out before we left. We knew the turbo should fit but the entire thing was mocked up and installed at the challenge.
15.5 is disappointing. Without the larger injectors we could not get enough fuel. I wanted to try and crush the fuel pressure regulator to spike fuel but there was no time to mess with it. Now considering the 15.5 was half throttle with a 2.6 60 foot that's not too bad. Best I ever got out of my old Cherokee was 16.3.
Now from what I've been told the Jeep is registered for an autocross at the end of the month. Hopefully we can get the fuel sorted out and have some fun. I'd also like to make another drag pass and see what happens.
<----jealous. Also, I think you may have officially made DILYSI dave stroke out, as I have not seen a post from him since he saw pics.
I don't think Dave (WilberM3) and I ever expected to get this much praise for the Jeep. You guys are awesome. It makes me so happy and it makes the countless hours of hard work worth it.
It has pretty much all been said but if you need more information please feel free to ask. I started putting together a build thread last night and hopefully I'll have time to finish it tonight.
Yes, the overall 1/4 time was a bit disappointing but we REALLY built the turbo setup at the Challenge. We didn't just bolt it on with parts and a tune that we already figured out before. As Pseudosport said, all we had done before we left was weld up the manifold and the down-pipe. We were cutting all the turbo plumbing and couplers on Friday night trying to make it all work and figuring out the oil feed and drain Saturday morning. It is amazing that it made it down the 1/4! haha
We went very conservative budgeting the turbo setup because we weren't positive how much we would need to use. So the good news is that we actually have quite a bit of budget left. First thing is to get much larger injectors. The 24# injectors hurt us a lot. We hoped the junk yard waste gate actuator was under 10psi but we saw 13psi which is way too much for a stock Jeep head gasket and WAY too much for the fueling we had.
Gentlemen, we can rebuild him. We have the technology.
Thanks again for the kind words, it means a lot.
You'll need to log in to post.