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  View original topic: Racing Engine Time Lapse with Startup
MichaelBrenner Mon May 26, 2014 11:09 pm

Hey Guys, I just finished rebuilding this spec motor. We are following the SCORE rules for the 1/2-1600 off road racing buggy class.

Here's some basic background on this engine:

85.5mm custom JE pistons
Stock connecting rods balanced to lightest un-touched rod.
69.5mm offset ground crankshaft (no counterweights)
Lightened flywheel
Stock dual port cylinder heads w/stainless valves, double springs, cut for 12.5:1 compression!
custom length 0.035" chromoly pushrods
Solid rocker shafts, swivel feet adjusters, stock rockers
24mm restrictor plate under pic 30 which connects to the adapter for the dual port manifold.
Power pulley
power steering pulley and power steering pump bracket
1-3/8" header with REAL merged collector
Dual pattern camshaft (intake is much more aggressive than exhaust since this is a restrictor plate motor)

Got any questions for me then fire away, no I won't put it on a dyno or tell you the cam specs......

Check out this video, I hope you guys like the time-lapse part, it was fun making it!

Don't forget to Like Brenner Racing on Facebook

Greezy Joe Wed May 28, 2014 7:29 am

:shock: Nasty sounding motor :D

midtravelmidengine Wed May 28, 2014 7:58 am

Man i LOVE hopped up little motors. Do you get cams from Web?

Not 100% on all of the rules but with the JE pistons do they have to be the same weight as the original pistons or are you allowed to lighten?

Anything fancy done to the stainless valves or is that not allowed?

with the 12.5 compression i assume you are running vp110 or are you running something different? is E85 allowed?

Thanks!

Steve Arndt Wed May 28, 2014 9:29 am

Tell us about the "boost bottle".

mcmscott Wed May 28, 2014 9:46 am

You should bring it up here and put it on the dyno

philheese Wed May 28, 2014 1:21 pm

Great time lapse on the assembly. Engine sounds great!
Wonder what the power output is. Good luck with it.

jps1145 Wed May 28, 2014 3:27 pm

Other then the squirters, anything special about the bottom end assembly? Any top secret side clearances or mods to the rods?
I have a hard time keeping rod bearings alive in my desert race motor... Do you use any special brand?
can you dry sump these? is that even necessary?

Oh yeah... I learned how to ride a motorcycle on one of them Trail 90's in the background about 35 years ago... :-)

Nice work!

MichaelBrenner Wed May 28, 2014 4:14 pm

Thanks guys, glad you liked it!

It really depends on who's dyno you run it on, none are the same and the way you operate the dyno matters a lot too. I would guess this motor is around 85-90hp on DRDs dyno, my class 11 motor wasn't far behind with less cam but otherwise same specs.

The cam is from FAT Performance, it's a custom grind from SLR with more than 250 degrees @ 0.050" on the intake lobes, super specific restrictor plate grind.

The JEs are very light and very trick, they have a much better ring package as well which I think is worth the money.

Yes, we run Sunoco 110 leaded, car should get about 6 mpg during races. Learned the hard way a few years ago that you gotta have cold plugs in these little guys, they get grumpy with the wrong plug. Alcohol fuel is not allowed.

The valves are 'special' and so are the seats, and the valvejob for that matter. This is a motor that has had no expense spared......

The purpose of the boost bottle is to increase the volume of the intake manifold. By adding that extra volume below the carb, the theory is that the vacuum signal will be stronger when going back to WOT after letting off for a turn or bump. This makes the main jet start working quicker. Remember, these cars need lots of on-off throttle application to negotiate turns and manage momentum through bumps and jumps, getting that crisp throttle response is important.

The motor is now in the chassis and we took it around for some test driving in the neighborhood, if you think it sounds good on the stand you should hear it with a load on it, sounds great at 6000 rpm upshift!

MichaelBrenner Wed May 28, 2014 4:18 pm

jps1145 wrote: Other then the squirters, anything special about the bottom end assembly? Any top secret side clearances or mods to the rods?
I have a hard time keeping rod bearings alive in my desert race motor... Do you use any special brand?
can you dry sump these? is that even necessary?

Oh yeah... I learned how to ride a motorcycle on one of them Trail 90's in the background about 35 years ago... :-)

Nice work!

Stock clearances on the rods & bearings. Make sure you polish new bearings with scotchbrite before you install them. No drysump allowed in 1600, gotta move up to a 12 car for that! Tricks for keeping rod bearings alive? Proper torque, good machine work, oil pressure! I see your a class 5 guy so you probably run a pretty big motor right? I have never had the chance to build or R&D an engine like that.

Thanks for the CT90 shoutout, it's original and fully restored, that is my apocalypse vehicle, I swear it's the most reliable machine ever built! License plate frame is 1978 original and says 'Just Passin Through' 8)

jps1145 Thu May 29, 2014 6:14 am

MichaelBrenner wrote: jps1145 wrote: Other then the squirters, anything special about the bottom end assembly? Any top secret side clearances or mods to the rods?
I have a hard time keeping rod bearings alive in my desert race motor... Do you use any special brand?
can you dry sump these? is that even necessary?

Oh yeah... I learned how to ride a motorcycle on one of them Trail 90's in the background about 35 years ago... :-)

Nice work!

Stock clearances on the rods & bearings. Make sure you polish new bearings with scotchbrite before you install them. No drysump allowed in 1600, gotta move up to a 12 car for that! Tricks for keeping rod bearings alive? Proper torque, good machine work, oil pressure! I see your a class 5 guy so you probably run a pretty big motor right? I have never had the chance to build or R&D an engine like that.

Thanks for the CT90 shoutout, it's original and fully restored, that is my apocalypse vehicle, I swear it's the most reliable machine ever built! License plate frame is 1978 original and says 'Just Passin Through' 8)
I've played with a few motors: 1915, 2276, 2332, all type 1. I've settled with the 2276 for now. Had major problems with overheating and cooking the oil which always led to rod bearing failure. I installed a HUGE cooler before the last race which seems to have solved my overheating problem, I don't even need to run the fan! I run a CB dry sump pump and tank so consistent oil pressure is not a problem. Engine holds about 2-1/2 gallons of oil. I built in squirters by just notching the rods this last build.
Now if can only keep everything else together... :-)
Good luck!

Bashr52 Thu May 29, 2014 6:45 am

Sounds good! No issues with the power pulley and cooling?

ps2375 Thu May 29, 2014 7:12 am

Coming from the H2O cooled world, I love the ability to run these motors on a stand like you have. Looks like a bad ass little motor.

midtravelmidengine Thu May 29, 2014 9:27 am

MichaelBrenner wrote: The cam is from FAT Performance, it's a custom grind from SLR with more than 250 degrees @ 0.050" on the intake lobes, super specific restrictor plate grind.



Can you tell me what the reason is for the class requiring a restrictor plate?

With over 250* at .050, how much does the restrictor plate affect the rpm of peak HP. is it still near where the 250* cam would put it without the plate?

sorry if that made no sense, its hard to put my question into words...

MichaelBrenner Thu May 29, 2014 2:03 pm

Remember that when you are running the fan at 4-6K rpm contineously, the fan is WAY out of it's design parameters, running a power pulley on the crank and sometimes on the alternator as well is needed to prevent belts from burning up. We also run a small (early style) fan in a genuine 36hp shroud. The motor doesn't get hot, it doesn't idle much ever and the high quality gas prevents detonation. We also run a VERY large external oil cooler like this:

http://www.fluidyne.com/oil-cooler_enduro_all-season_58mm-otsocfi.html

I love the engine run stand, I built it myself after a long time of starting motors on wooden blocks and crap like that. I rebuilt our racecar and had some leftover battery, switches, lights and gauges and figured, why not? Some basic steel fab work and the guys at work let me use their plasma cutter on the plate stuff made it come out pretty nice. It's on metal castors so you can simply wheel it around. I love it because it allows me to start it, run it in, check all the vitals are working, check for oil leaks, set the timing and adjust the idle speed. That way when it goes into the racecar, there are no surprises!

Restrictor plates are used in this class to make the single seat and 2 seat cars equally matched, single seaters are lighter so they get a 21mm plate, those motors need REALLY big intake lobes and still make less power. Restrictor plate motors are weird, it some ways you're simply trying to match the difference in flow between the intake side and the exhaust side. The exhaust is only about 240* @ 0.050", you just have to keep that intake valve open for a long time to get the motor to want to rev up to 6000. If this exact same engine had a pair of 40 IDFs on it, I bet it would make 25 more hp and rev at least another 500 rpm. Remember, all that air is going through the 1500 carb PIC 30 with 24mm venturi :(

mcmscott Thu May 29, 2014 3:05 pm

I like my run stand, you have to hook water to it tho
:D :D

mcmscott Thu May 29, 2014 6:27 pm

Nice towel!

MichaelBrenner Mon Oct 27, 2014 10:46 pm

After racing the newly freshened engine we realized we were running too rich :( So we made some adjustments with help from Tim at Voltzbitz on our Solex H30 Pic, big thanks to Tim, his work is top notch! I caught the tune up on the motor in the time lapse and dyno session after. Listen to this little guy scream under load at 6K :) Wideband told me we were on the money from 4-6K! Got it back into 1679 for the SNORE 250 this weekend. Big thanks to Darren at DRD Racing Heads for his support, he even lets me work in sandals bro....

Don't forget to like Brenner Racing Facebook to get our racing updates this weekend!


andy198712 Tue Oct 28, 2014 12:12 pm

Cool!

are those porsche squirters or?

yamaducci Fri Oct 14, 2016 10:29 am

Hey Michael, I know this is an old post but I was curious about a couple things if you are willing to share.
Do you run Total seal rings on either 1st or 2nd?
Is your crank wedgemated?
What is the approximate weight of the flywheel considering you have extra weight from the PS pulley? Do you run the bronze lifter bores?
What are "Special" valves and seats other than Manley SS with 45 degree seats cut?
Do you know the head cc's and are you running all the fins or is the first one cut off?
Do you use valve seals?
Who's solid rocker shafts are you running?
Have you had any failures where you switched to a different part vendor.
I just want to compare notes. If you don't want to share with the world please PM me.
Thank you



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