I've knew Jesus Padilla over 10 years I can vouch that he has more experience with the 20b then anyone I've heard about in the US. I think I would consider him before anyone else.

 

Kilo really knows his stuff

 

Im looking forward to see how much power ur set up makes. My car made 470 hp @ 0,7 bar before we ran out of fuel, have installed larger pump but havnt got it tuned again yet, anyway car need to go to the painter now but here´s a little clip of me moving it to get another car out ;-)

 

Thanks guys! Looks like Ray Wilson from PFS will be here early March.

Have two issues going on right now need to take care of before the tune.

For some unknown reason, the fuel keeps overheating and the pump / pumps cavitate in the tank. I'm only running 1 as a primary and second one under boost. However, when coolant temps get up around 200F and the car has heatsoaked in traffic for an hour, the pump starts whining, sucking in air, the FP gauge starts bouncing. Have to shut it down, won't restart at all until the fuel pressure holds steady and the pump sounds normal (take around 30 mins) The it runs fine again.

Upgrading the return line to a -6 an and installing a large aluminum finned in-line fuel cooler under the car this week. I think the 20b is dumping heat into the fuel system and the large Walbro 400 @ 12-13.5v constant is circulating that heat into the tank.




Secondly, WITHOUT the undertray and 60-70F ambient

Fans ON - 190F
Fans OFF -225F and climbing cruising

WITH the undertray and sealed intercooler/rad with tape, 65-70F ambient

Fans ON - 200-210F
Fans OFF - 210-220F crusing


Before ducting, the fans could pull air up from under the car between the Rad and I/c. Now, with ducting all the air has to come through the I/C which is good for cruising but sucks for traffic.

Hmmm.....I'm thinking about E85 now

 

Are you saying you have to run the fans while cruising to keep the temps in check?

David Hayes 20B also ran cooler without the undertray when he had a front mount.

 

you have pm.

Do you have large submerged pumps? They may be boiling your fuel. I have 2x externally mounted bosch 044's and don't really have cavitation issue. They get pretty hot to the touch, so if they are submerged, I could see how they would heat up your fuel...? just a thought.

 

Yes

With the fans on and no undertray I held 180-190F but it would creep every so slightly the entire time.

WIthout the fans and no undertray, temps will SKYROCKET; as soon as I hit the fans they'd plummit down to 180F in no time flat.




With the Undertray, **** gets strange. Cruising without fans will now yield 200-210, and makes no difference fans on/off. Can't get it below 200, ever.

 

Twin wally 400's submerged, only running 1 around town.

I'm not even using boost.

Never had an issue in the past with the walbro in-tank on the 13b, although I never had a mechanical FP gauge that would show the cavitation. That motor was a BITCH to start when heatsoaked after trafffic. But it would still start. The 20b refuses to even make a hint of fire until the pulsation/cavitation has completely resolved. Its DEFINITELY not compression, I have this motor idling at 750rpm and lighting off with the first revolution if the temps are in check.

 

Ok, after talking with Chris at Banzai, he believes primary issue with temps are likely the Oil Temps exceeding the water temps.

We run similar setup, same I/C and Rad, although his 20b does not have underdrive pulleys and he uses an idler on the water pump.

I've purchased the following:

2x 25 Row Oil Coolers
-10 Lines and fittings (not going to run a thermostat, doesn't get cold enough here)
-6 return line for the fuel system
-mishimoto 160F water thermostat



And this ebay supremo trans cooler, goign to mount it along the frame near the gas tank, and run the -6 return line through it with hose barb/clamps. Shouldn't be an issue as its not a pressure line.


Then, inside the tank, I will extend the new bulk head with submersible line all the way to the bottom, install a 90 degree brass fitting on the end of the line and extend that out to the corner of the tank so that any aeration is away from the pickups.


Any other ideas for getting the water temps down?

 

Electric water pump?

Also, after reading are you essentially saying people with 20b swaps should just go with larger than 19 row oil coolers?!?!?

I have new oil coolers I never got to use if this is the case .

 

I'm not saying that;

I'm saying that I have STOCK R1 oil coolers (these are only 10 row right?) 25 rows should be an improvement over these stock cooler. So would 19 row.
However, I am still questioning whether larger than factory coolers even makes a difference in regular cruising as compared to something like an electric water pump.

I've heard people with EWP having DRAMATIC results.

I want to do whats most effective so share you thoughts guys!

thanks, and Ill have a 700rwhp pull coming soon i hope

 

Ahhh ok thanks for the clarification. Also, my plan is to run an EWP on my 20b set-up so if I ever get mine done I'll keep you posted!

700rwhp! Wowsa!

 

It is really simple to determine if it will make a difference. What are your current oil temps?

If they are currently running at 180F or below, then changing the coolers won't make any difference at all, since that is not what would be driving the water temps up.

 

Well it would be simple if i had an oil temp gauge

Installing one this weekend hopefully in the oil drain plug

Going with the Oil Coolers regardless of the issue, can't hurt

 

For the fuel issue, i think you are on the right track. Although I don't think a fuel cooler is necessary. There are many people with that much pump in the tank (meaning they heat their fuel just as much regardless of 13b or 20b). I think it's the aeration problem, is it currently just dumping straight into the tank without a downtube? Piping it away from the pump pickup should help.

 

Banzai is on point.

Don't try to "bomb-proof" your car. That's a very good way to spend the money. Many rotary owners spend tens of thousands of dollars to make the build as "perfect" as possible. To be fair, that's part of the fun. I've been there. However, I do think the wise thing to do is to identify each problem and approach it systematically.

As for upgrading the oil cooler, I think you're on the right track. 20B does need upgraded oil cooling system per our experiences. But I do agree that you should get oil temp gauge first and if that reads normal, upgrading oil cooler will not help any bit unless you plan to push it much harder.

For your fuel cavitation issue, remember that there are only 2 ways that will make your fuel boil. One is high fuel temp. Another is low pressure/restriction at the fuel pump inlet. If you're returning to your tank, I really don't think you're dumping enough heat to boil a tank full of fuel. If you're suspecting that, measure the fuel temperature (oven temperature probe) and act accordingly. I think it's some sort of restriction at the fuel pump inlet, like fuel sock. If there is a restriction, and if you're fuel pump is sucking fuel against a restriction, you'll lower fuel pressure at the pump inlet and that can boil the fuel. In other words, there is no sense in changing out return line and upgrading other aspects of the fuel system if you suspect cavitation. If you can regulate the pressure as low as you can, the existing return line should be fine. If you just want a stainless steel braided return line, that's another story

 

Extremely good points.

Makes me wonder if using the stock fuel socks, which have less surface area than the larger Walbro kit socks, are causing that restriction...

 

i'll take your dual oil coolers too if you upgrade

 

Aside from running lower voltage when possible, thus helping with cooling (or help in not overheating your pumps), how much can a fuel pump speed controller benefit you? I mean if you don't have one already? Just throwing my two cents

 

Are you gonna eventually go V mount?

 

Thought I'd stop lurking and chime in

Nice project so keep up the good work.

T-von is right, had the same exact issues you describe. Did a bunch of testing regarding temps and the effects of an under tray (at least on my 20B setup) and concluded the under tray hurt temps and made them rise by about 5-7 degrees celsius. My testing was in Orlando FL during 90+ F temps. So the under tray came off and it's somewhere at Kilo Racing.

I have now though moved to a v-mount setup. The entire setup (radiator, IC, and piping) has just been coated with a ceramic TSD (heat dispersant) and will soon be back on the car. I am also going to run Engine Ice (Home) to help but I will test that and post up results.

I do also run two 25 row oil coolers and the RE Medy water pump.

In short, the 3 rotor makes some heat so you need to do the basics possible to keep it cool. I'd say the biggest mod you can do is to swap to a v-mount setup. That should eliminate your issues, especially if you live in the South like I do.

 

I had a big front mounted IC and the engine kept overheating, swapped to an "L" mount where the IC lies horizontal and the problem was solved. I run stock dual oil coolers and even in France at Lemans last year when it was f*cking hot the temp never got above 92C! We sat in queues for hours and did some pretty crazy pulls too!

 

Thanks for sharing David,

I wish I could move to a v-mount, but that would require very extensive modifications to fit. Probably would have to use an ugly aftermarket bumper, chop up the front frame support, move the engine back in the firewall. This turbo is so massive it has to sit in front of the front strut which limits space serverely, I already have my radiator jammed up under the front crossmember.



Yesterday I removed the ducting that sealed the radiator to the intercooler, which forced ALL of the air through the i/c through the radiator.

I believe the high temps could be from heatsoak caused by the fans being unable to pull air through both cores. This probably explains why removing the undertray increases effeciency as it provides a clear path for the fans to pull air.

So, last night I took at look at the car. I removed the bumper and raised the intercooler slighly on the brackets. This opened up more space below the intercooler. My radiator sits very low, as its tucked under the support frame so there a few inches sticking down now below the intercooler. I cut out a good deal of material from the lower bumper meat which now allows a small window of fresh air under the intercooler.

I'm hoping this will help as its could be path of lesser resistance than the intercooler so long as the sides and top are all sealed to the radiator. We'll see what happens today!

Curious to see how you fit the v-mount.

 

Ahh crap, I figured the oil coolers didn't matter one bit when youre sitting Well, at least it will have some increased capacity for load and track days

Glad to hear you have the temps figured out now with the v-mount. I'm determined to find a way to make this FMIC work. I love the look and the simplicity.

Hoping oil coolers, 160f thermostat, and fuel cooler will finallly help

If I have to run e85 so be it

How the HECK does MadMax run that massssiivvee FMIC on that 4 rotor FD. There must be a way.

 

Determined to make this FMIC work! Ill find some way to duct it.

Absolute worst case scenario, there must be a way to modify the front lip, or the undertray to scoop air under the intercooler and into the radiator. The radiator sits down past the intercooler quite a good bit.