Magnethead's Racing Updates: 2012

Magnethead

Magnethead

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Intake's not actually bolted down. waiting on pushrods and some other stuff.

aiming for 900 horsepower out of 505 cubes. We had ~830 with the old setup.

0.115 intake valve clearance, .130 exhaust valve. Custom cam @ 107.5 dgrees (108 after chain stretch)

115 CC chambers
50cc piston domes (0.70 high)
4.375 x 0.040 gasket
deck height 0.040 in the hole

aiming for 14.8-15.2 compression. Anything past 15.3 gets interesting on 10% nitro.

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Hearing it fire for the first time is better than, well you know...

btw, invest in a good vapor/fume respirator, shop rags just don't cut it. DAMHIKT

After Ernie and I dam near got overcome we decided we'd do any future lenghty run ups outside.:booya:
 
WOW,not bad for a redneck shop .

ps;why did the cruew guy grab the rag?.......LOL
 
getadietdew said:
btw,do they still sale addatives for smell?
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yea they do, but its bad for your health. The additives just make you want to smell/inhale what you shouldn't.

I'm actually "the crew guy". Dad's in the ****pit. Saturday was reversed roles, I was in the ****pit and dad worked on fluids and fuel management.All measurements are taken at high idle, 2500 RPM.

As of right now, we'll probably be pulling about 3/4 quart of fuel per second at WOT. Once we get a high-speed lean-out valve on it, it'll be the better part of 1 quart per second for 3 seconds and 5/8 quart per second for 2.5 seconds. Running a 2 gallon pro-stock fuel tank. Leaving 3/4 gallon for getting to the staging lines and coming back to pit. Gonna be close at the longer tracks (crandall and motorplex) but that's what the auxiliary fuel tank is for (an extra quart).

Base timing is 34 degrees. We'll test on Friday and see if it likes 36 better. We ran 38 last year but that was with all kinds of issues we didn't know about until we pulled the heads off.

Launch retard will be 5, 8, or 10 degrees on timer, starting at 0.5 seconds and ending at 1.1 seconds. Shift at 1.7 seconds, engage high speed lean-out at 2.8 seconds.

Looking to add a digital tachometer with a built-in function that will shut down the motor if (it's above 4500 RPM OR accelerometer is not negative) after 6 seconds has elapsed (detecting off accelerometer @ 1G). AKA if hung throttle or delayed braking, shut down the engine.
 
SST55 said:
Hearing it fire for the first time is better than, well you know...

btw, invest in a good vapor/fume respirator, shop rags just don't cut it. DAMHIKT

After Ernie and I dam near got overcome we decided we'd do any future lenghty run ups outside.:booya:
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We're in an HOA. Yea, that redneck shop is our 3 car garage, LOL. 2 cars inside and 2 trucks outside.

We're lucky that most of the neighbors don't mind the noise. We only open 2 doors halfway plus the door to the backyard for a cross-breeze to help muffle what gets out, but our friend 6 houses up says he can still here it in his house. Mom was walking the dog while we were putting it on the trailer once, said she could hear it from the complete other diagonal side of the development half a mile away.

ya, it's loud. LOL. Lucky nobody has called us on the noise ordinance or anything. We ran it for an hour saturday- burned through a half gallon of gas and 1.5 gallons of methanol.
 
Any chance we can get a driveway burnout and a couple Hard launchs??? :D Sounds great!
 
Now someone with a degree in sound engineering can probably answer this as to why but you could hear us fire it up from further away if the truck was inside the garage vs being outside. My theory is the garage acts like a speaker enclosure or box.

108 octane racing fuel fumes should be sold as a aphrodisiac:D.

You really need repirators, not fun calling 911 and sucking on oxygen being called dam fools.:rolleyes:
 
SST55 said:
Now someone with a degree in sound engineering can probably answer this as to why but you could hear us fire it up from further away if the truck was inside the garage vs being outside. My theory is the garage acts like a speaker enclosure or box.

108 octane racing fuel fumes should be sold as a aphrodisiac:D.

You really need repirators, not fun calling 911 and sucking on oxygen being called dam fools.:rolleyes:
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The 112 wasn't bad at all. This methanol is something else. Heard the M-5 is even worse....it has 10% nitro by volume.
 
Bucky Badger said:
Mag, you need to get one of the GOPros for the car this year
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Had an SD last year. Dad got me the HD for christmas and I matched it with a 16 GB high speed SD card. Plan to have the HD on for every pass this year recording in 720P 60 frames per second, with the SD on for select runs, plus my off-board camera. One of the local photog's wants to use our car as a video anchor since it stands out and is well recognized.

I've played with it some, let me tell you, that 60 frames mode KILLS disk space. That video of warming up in the garage? 1100MB for 7 minutes. I cut it down to 800 MB for 4 minutes to get it on youtube.

http://mcdermottfamilyracing.com/

first video, you can see me run up and pull some debris out of the groove right before dad stages

second video, it went up on the wheelie bars and unloaded the chassis.

We won a burnout contest with the last 2. We had the completely wrong torque convertor and car was a slug, this was also before we lowered the back of the car 3 inches.















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Magnethead said:
Had an SD last year. Dad got me the HD for christmas and I matched it with a 16 GB high speed SD card. Plan to have the HD on for every pass this year recording in 720P 60 frames per second, with the SD on for select runs, plus my off-board camera. One of the local photog's wants to use our car as a video anchor since it stands out and is well recognized.

I've played with it some, let me tell you, that 60 frames mode KILLS disk space. That video of warming up in the garage? 1100MB for 7 minutes. I cut it down to 800 MB for 4 minutes to get it on youtube.

http://mcdermottfamilyracing.com/

first video, you can see me run up and pull some debris out of the groove right before dad stages

second video, it went up on the wheelie bars and unloaded the chassis.

We won a burnout contest with the last 2. We had the completely wrong torque convertor and car was a slug, this was also before we lowered the back of the car 3 inches.
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lov the sound of a big motor stageing.
 
Cleared the videos from the quote to shorten the page a smidge.

It'll sound better this year. We cracked one cylinder about 5 races into last season but didn't know it until the 3rd race to the end when water and compression both started disappearing. It was cracked 180 degrees around #8 by he time we tore it down. We cracked #4 a little later in the year I think, it was a much smaller crack. And at some point we also blew an intake manifold gasket.

We figure on at least 60 more HP out of the box, and maybe another 10-20 on that once we get the fuel system worked out with the bypass valve. Our best prior was that 5.55 towards the end of the year, we think we can hit the 30's with M-5 fuel (10% nitro) and a good track. When we first put the vacuum pump on, it got us 5 hunds at 7 inches, we were at psi at end of year. We're gonna run it between 12 and 15 inches, so that should be worth 7-10 hunds. The fuel bypass is supposedly worth 3 miles per hour and another 5 hunds, totalling 12-15 hunds (5.40). The M-5 is worth another tenth easily (5.30).


Not bad for 500 cubes and 3000 pounds.
 
I have these in reverse order- we were fighting a stumble in the second video (taken first), which we fixed by richening it 3 flats on the barrel valve linkage after i turned the camera off. Then I took the first video.

After we scaled it and got everything buttoned up, I realized we never uncorked the vent line for the fuel tank. So we're going to undo those 3 flats or so at the track tomorrow.



 
DA was 100 feet.

I think we shot well past the 900 HP mark.

Kennedale's doing another test next saturday, if we still can't hook, and even if we can, we're going to the motorplex on sunday for a closed testing session, supposed to be 10 or 15 cars.

Nitro dude, does this look more like a bracket car, promod, or funny car? We had front shocks full loose for weight transfer, rear shocks at 5-9 for minimum hit, tires at 7psi, with 10 degrees of timing pulled for the first second.

super slow mo coming soon.

 
505 cubes, .040 gasket, 115 cc chambers, 50cc domes, .004 deck height, cam set at 108 degrees with custom grind for our setup, mechanical fuel injection with highspeed leanout bypass, 12 inches of crankcase vacuum, 1.76 first gear, 4.88 rear gear with 32x16 steamrollers.

swept volume = 505 cubic inches
combustion chamber size (roughly) = 115-50 = 65cc's

at BDC = 63.125ci + 115 cc chambers + .040 x 4.38 gasket = 1034.43 cc's + 115 cc's + 9.86cc's = 1159.29 cc's
at TDC = 65cc chamber + .040 x 4.38 gasket + .004 x 4.35 deck = 65cc's + 9.86 cc's + 0.98 cc = 75.84 cc's

159.29 / 75.84 = 15.28:1 compression

*Ahem* I think I know where that extra horsepower came from....the 4.88's are the other half of the problem.
 
picked up a prototype for the car toys i'm making...Which lens colors look best for the white LED's?

Also got red, blue, green, and orange to work with for LED's.

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testing in kennedale today/saturday and at texas motorplex tomorrow/sunday.

may or may not be a messy mad dash to swap torque convertors tomorrow night.
 
Started the day with a 5.60 sputtering in high gear

Ended the day with a 5.56 @ 121.67 with room to spare to go faster tomorrow. May not touch the 40's, but certainly will be very low 50's.

video soon.
 
You have a very nice set up Magnethead. That is an awesome looking engine. It sounds great.
 
went testing tonight and played with a few things on the car. Got some good data for tomorrow.

Big thing was playing with the launch control. The track temp was 58 degrees down track and 63 on the starting line. We set it up to pull 10 degrees of timing out of the motor from 0.25 to 1.00 seconds. It stalls on the convertor at 0.30 seconds.

That extra .05 between initiation and stall, dropped the stall 150 RPM from 6500 to 6350. Sixty foot time went from a 1.218 to 1.216. Thinking about putting a 5 degree chip in place of the 10 and using it all day tomorrow.

Launch control is not traction control, but uses the same theory. Traction control detects a sharp change in driveshaft RPM and pulls 1 or 2 degrees of timing, or compares the corrected front wheel speed to the rear wheel speed, and pulls timing until equal.

Launch control pulls massive amounts of timing based on a timer system. Basically we look at the datalogger graph and say "take away power here" and program it into the timers.
 
track was good through time trials. 10 dragsters showed up (8 in the 4.50-4.60's and 2 in the 5.0's) and we had 14 door cars in quick, maybe 40 or so combined for super pro.

went 5.59-5.60 for all 5 time trials, but come first round, bogged motor down by dead-hooking in quick, and blew them off in super pro 45 minutes later.

by end of first round, only 4 dragsters were left between the 2 classes- both 5.0's, then in one pair, left lane ran 10.xx to right lanes 13.xx, in another pair, 6.72 left lane beat a 10 flat right lane.
 
just did data analysis with some old runs. We think something is wrong with the MSD box. We looked back at old runs when we had the carburetor and distributor timing system, and it did the same thing as it did today with fuel injection and crank trigger. We're pretty sure it's losing a bunch of timing somewhere. We're going to do a double check by putting all zero chips in the launch control positions, and see if it goes away (Me thinks high impedance input failed). If it doesn't, time for a new box.
 
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