Hello,
Starting the process of dreaming about building a F/DT class truck for Bonneville. In the rulebook it says you can have a maximum engine setback of 2% of the wheelbase.
My engine plans entail running an in-line 6 cylinder diesel in a mini-truck which normally come with 4 cylinder engines. In this scenario, the rear portion of the engine is going to be sitting back farther than a stock 4 cylinder and likely by more than 3 or so inches. Am I overthinking this or how do I calculate how far I can cut into the firewall to make the engine fit behind the stock radiator location.
Thank you,
Adam
See the definition of setback on page 58 of the 2020 book. It is measured to the front sparkplug hole.
I don't see a problem with having stepfront rather than stepback. The rule was written (I suppose) to keep from getting the pickups into an "altered configuration" with added engine setback. But if you want to not cut back into the cab and have it farther forward than stock, I'd guess that would be okay ? if you made sure of the rules regarding radiators and such.
Before I went that way, I'd sure run it by an actual SCTA official such as Jim Dunn, listed in the back of the rule book.
Well the rule really has nothing to do with the firewall... it is about engine placement. Since you don't have sparkplugs it is the measurement from front spindle traverse centerline to the first cylinder centerline. So if you had a 100 inch wheelbase truck your 1st cylinder center could be back 2 inches from the spindle centerline.
But my opinion is worth the same as all internet babble.... and as much as it pains me to write... take Stan's advice and contact the truck chair for the final answer...
. . . and remember, putting more weight on the front ain't like darts ? you might need more out back to keep those tires from spinning.
O.K. That helps. I was afraid that the longer engine would run afoul of this rule. In measuring out various mini-truck engine compartments, I'm going to need to cut into the firewall a couple of inches to get proper clearance.
Thank you again,
Adam
Do they make a V-6 diesel? That might fit without all of the chassis mods.
I'm with Stainless, I know nothing. But, to calculate the setback you need to know the "setback" per the rule, (4.AA) of the stock engine. Which may be in front of, on or behind the spindle line. A setback of a different engine would be with respect to that position. I think the setback rule came from the circumstance in Altered or CC, where a stock (read V8 mostly) engine is being moved back and how much is being regulated.
This issue came up on my car, in impound, last meet. Was asked if the block plate to which bellhousing mounted, was moved back. My engine was a long 5 cylinder in place of a 4. it was moved forward as much as I could (need the radiator-/GC rules) to avoid cutting the firewall. I think the #1 pllug is forward of the stock location. But they didn't ask that, asked where the back of the motor was. Inspectors.......... :roll:
Very interesting. I'm not surprised. Inspectors have been known to read things into the rules that are not there ? just like some of us.
I've even had "certifiers" add words to a rule and quote it to a committee head who agreed. It cost us a record. No one said it was supposed to be fair.
Hey Jack.....this has nothing to do with engine set back....but....what engine are you running now....Paul...
Paul, Jack will answer I'm sure, but he is running the coolest out of the box thought engine I've seen in a door car.... 5 cylinder 2 stroke... He has an engine cover made of expansion chamber pipes.... it is wild... but to think of it... so is Jack.... so... just one of those normal car engines you never see in anything... cromag :?
While a V-6 would certainly be shorter, the in-line 6 I plan to use has the most aftermarket support available and overall, packaging is much easier with an in-line engine. I've been playing with smaller diesels for a number of years and have had pretty good luck wringing decent HP numbers out of them. My current toy is a '93 Landcruiser running a 3.9L Isuzu with a set of compounds I created backed by a 4L80E. Currently running 32 lbs of boost as a daily driver, but the smaller turbo is still doing over 50% of the work so there is more power available, but really not necessary for the intended purpose of this vehicle. Pic should be attached below, but this is NOT the engine I'd use for any LSR effort. It's too "industrial" for high speed activities, but works great off-road. I'm currently able to push 22lbs of boost at 1600 rpm and EGT's are hovering around 1200 at WOT. This pic was taken just before I buttoned everything up and cleaned up some of the loose wiring. The intercooler pipes were also missing a few clamps at this time as well.
Back on the setback question, I felt better after reading the rulebook. I'll finish reading the 2020 rulebook from cover to cover over the next few weeks.
Adam
So for the past year when the new engine was under development and installation I was pretty quiet about what I was doing. Had to find out if it really worked. Had no actual dyno (did dyno a 2 cylinder mule with my cylinders, carbs, pipes etc) nor actual run the car down a track (had planned to go to ECTA meet in April but that cancelled, and turns out wasn't ready anyway (found out in June at the 2 cyl dyno session that the pipes made in Canada were incorrect and I had to cut them and rework a bunch of stuff to now make the new configuration fit). So speed week was the first outing. Handling problem from coolant tank position, a spin associated with that and then at the end managed to keep it straight for the below noted 194. In addition to the engine and anticipation of better speeds, limited space for big tires and rear gears I had installed a QC. After Speed week I sent the guy who modified the sub frame for that to fit some notes about my times and some photos. We had talked a lot about what I was doing and thought no LSR experience (Drifters and such) were very interested. They put it up on their Facebook page and within a day had about a 1000 hits. To keep this more or less short I didn't back up the above time, found the reason why when I got home, fixed the coolant tank handling problem and went back for World Finals. With many ambitions which for several reasons didn't happen but did get the G/FAlt record. While there many people stopped by and said" Oh, I saw this on Facebook, the internet or somewhere" Videos now out there too. Anyway, couple photos attached. It is a 5 cyl, 2 stroke based on Arctic Cat snowmobile cylinders. Head and crankcase are billet CNC machined.
Engine in place, carbs.
All I can say is WOW....good stuff Jack...keep up the good work...Paul..
Adam, will your race diesel have water injection?
Not sure as of yet. It depends on what my EGT's look like when I start running the engine I plan on using. My biggest problem is finding enough room/space to get started. My day job tends to get in the way of my hobbies and I have 3 daughters between the ages of 11 and 16, so time is also a commodity in short supply. While I was stationed in Utah from 2012-2016, I managed to attend several races in Bonneville and managed to get washed out of several others so that is where the interest in LSR started. I think I was there the first year Steve Menendez raced his diesel Rampage ( I spent a fair amount of time looking it over) and when the record for G and F diesel classes was in the low 130's, my modded Toyota 2L would have been a contender for the F class, but those records have been bumped up considerably while I was out of country and living in Belgium from 2016-2019. While in Europe, I frequented Germany on a regular basis and would get to exercise any vehicle I was driving on the Autobahns. I like diesels, like building performance into them and would like to do some speed racing. My oldest daughter and I have been autocrossing a Subaru this summer and she does most of the off-road driving in the Landcruiser these days and now she says she wants to drive fast on the salt. She's still a few months away from getting her license, but it would be cool to have her as my co-driver in a LSR attempt. No matter how I look at it, I'm several years away from showing up at Bonneville with a vehicle, but I would start by putting the chosen engine into the vehicle I plan on racing and daily drive it for a while as I bump up the performance envelope on it. Once I'm ready to commit, I'd then commence with turning the chassis into a full fledged LSR vehicle, but I'm a firm proponent of have a engine/trans/drivetrain well sorted long before race day and even high performance diesel can still be tame daily drivers, especially with compound turbos so they spool at low rpms. Case in point, I started playing with my NA Toyota 2L (2.4L) in 1995 and back in the day, the generally agreed maximum safe boost was 8-10 psi and EGT's not to exceed 1100 degrees. The NA engines came with piston squirters, so it was no big deal to build a J pipe and bolt a turbo onto them to double the hp. I pushed the envelope well beyond that and even sent my pump and injectors to Australia to have them re-worked there. When I told them what I wanted done, they said "we don't set them up that hot," but after explaining what I had done to date and how I was monitoring everything, they agreed and I have run that pump since 1998 and I'm pushing 22lbs of boost with EGT's under 1200 without issues. During a move across I-70/Kansas a few years back, pulling a box trailer and pushing 50 mph winds, I ran full boost for 12 hours straight and the truck never missed a beat. That truck is currently in storage due to a rotten/rusty frame, but I'll re-use the engine for a future project at some point. When I get serious, I'll start a build diary as well.
Also, that 5 cylinder 2 stroke looks amazing. What is the displacement and how much HP are you getting out of it?
Thanks,
Adam
Quote from: Adam R on December 13, 2020, 10:05:43 PM
Also, that 5 cylinder 2 stroke looks amazing. What is the displacement and how much HP are you getting out of it?
Thanks,
Adam
It is 1958cc and the dyno mule (2 cyl=800cc) made 92hp/cyl so the 5 is in the 450range. WAG
"Throw together something in a hurry so I can race with my kids while they are young enough to want to do it." That was my plan. The top speed was 99.98 mph during the first year on the salt with a 790cc bike. That is real slow but my youngest boy saw it being done and he came back the next year and set a record on his modified dirt bike. I saved the hard and technical stuff for my dotage after the kids left home.
5 cylinder 2-stroke has got to sound wicked, can't wait to hear it. :cheers:
92hp per 400cc's, it must be turning some rpm.
Don
This link is to a Facebook page from Church of Speed who was photographing and videoing at WF. I know some don't like FB. It is from the start of my qualifying run at WF. Start and push off and then you can hear it rev and leave the push truck and shifts. https://fb.watch/2nxhrwG76l/
This link is to a down course view from Speedweek when I did the 194 pass, 195 exit speed. https://www.youtube.com/watch?v=kaLxueuOmTI&fbclid=IwAR2VmBDj3ACEQkEqQbQVfGDw37JtTlaWfhBRQ3b9ak_a9HxtAnett-ML3_Q
Jack,
Start your own thread on your motor. That is an interesting piece and I love two strokes!!!! 450 hp is strong but when GP1 was running 500 cc two strokes the best one were making over 275 hp so you have some room for more hps.
I thought your old motor was innovative this one is way past that!
Rex