Re: Consistency... Engine Build question
[Re: Jeepmon]
#1128577
12/06/11 03:25 AM
12/06/11 03:25 AM
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Joined: Jan 2003
Posts: 19,304 Las Vegas
Al_Alguire
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I Live Here
Joined: Jan 2003
Posts: 19,304
Las Vegas
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Do it right the first time good parts, good machine work and good assembly and all should be well. More or less power is not what makes a consistent piece. Attention to detail does make all the difference.
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: Consistency... Engine Build question
[Re: Jeepmon]
#1128578
12/06/11 01:57 PM
12/06/11 01:57 PM
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Joined: Jan 2003
Posts: 5,893 Florida
Locomotion
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master
Joined: Jan 2003
Posts: 5,893
Florida
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A lot is making sure YOU do EVERYTHING the same each run. Everything the same temp, stage the same, launch, shift, etc. Of course, you have to factor in weather changes, like wind, humidity, temps, barometer, etc., so you can predict/dial-in accurately.
While the engine combos and jetting needs to be "right", engines with higher compression, more cubes and bigger carbs "tend" to be more consistent because weather affects them less. In other words, a 440 Cuda will be easier to make consistent and predictable than a slant 6 Dart!
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Re: Consistency... Engine Build question
[Re: Locomotion]
#1128579
12/07/11 12:22 AM
12/07/11 12:22 AM
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Joined: Nov 2004
Posts: 8,094 Sunnyvale, CA
Jeepmon
OP
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OP
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Joined: Nov 2004
Posts: 8,094
Sunnyvale, CA
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Quote:
While the engine combos and jetting needs to be "right", engines with higher compression, more cubes and bigger carbs "tend" to be more consistent because weather affects them less. In other words, a 440 Cuda will be easier to make consistent and predictable than a slant 6 Dart!
Thats good information.. Thanks
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Re: Consistency... Engine Build question
[Re: Jeepmon]
#1128580
12/07/11 01:36 AM
12/07/11 01:36 AM
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Joined: May 2004
Posts: 2,864 IN
Irun5snd8th
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master
Joined: May 2004
Posts: 2,864
IN
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I have a firm belief that thicker cylinder walls increase consistency. Its logical to think that a thicker cylinder wall will distort less and have a more consistent compression.
AFCO, Rons Fuel Injection sponsored Dodge Challenger
Mention Street Lethal Motorsports
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Re: Consistency... Engine Build question
[Re: Irun5snd8th]
#1128581
12/07/11 02:45 AM
12/07/11 02:45 AM
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Joined: Jun 2003
Posts: 52,972 Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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This is just my opinion but if the engine is a decent build where you dont have friction from parts wearing out it should be consistent... might be slow but it should still be consistent... I made 8 passes in a row all within .008 from min to max on a 10.0 set up and that was a FEW hours spread...my engine isnt anything fancy but I also believe fuel has a big factor.. I run E-85 and I believe alky is even better for consistency
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Re: Consistency... Engine Build question
[Re: MR_P_BODY]
#1128582
12/07/11 10:30 AM
12/07/11 10:30 AM
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Joined: Jan 2003
Posts: 9,963 Frostbitefalls MN (Rocky&Bullw...
gregsdart
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master
Joined: Jan 2003
Posts: 9,963
Frostbitefalls MN (Rocky&Bullw...
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A motor build that will go the most rounds with the same power will let you establish a better history to dial from. If I were to build a motor just for the purpose of being as deadly as possible, both me and car, it would have just enough power to go 10.00, (no heavy suit,etc) have high compression but a street roller or flat tappet cam so the valvetrain is as reliable as possible. Build the motor big, keep the revs down. Example- Small port 512 low deck with a 590 mopar cam, 13/1 compression with E85, probably with mechanical injection. This motor would only need a 5800 to 6,000 rpm shift point and last a long, long time. If you have a light chassis and a smaller motor will do the job, I have considered a low deck 400 with an offset ground 383 crank to build a 406 to 426 cube motor. Cheap to build, easy on parts.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
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Re: Consistency... Engine Build question
[Re: tboomer]
#1128584
12/07/11 12:22 PM
12/07/11 12:22 PM
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Joined: May 2004
Posts: 3,210 robin hood country
deaks
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master
Joined: May 2004
Posts: 3,210
robin hood country
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Ted Have you tried shifting it lower, you might be suprised. Mick
69 Dart GTS 440 mopar .590 cam, Edelbrock heads, 3200# best et 6.45, 106.78, 10.14, 132.88 mph, 1.47 60ft best 60ft 1.36
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Re: Consistency... Engine Build question
[Re: Jeepmon]
#1128586
12/08/11 03:14 PM
12/08/11 03:14 PM
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Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
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master
Joined: May 2008
Posts: 5,399
Aurora, Colorado
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Well I have had the 505 short block together 3 times so far. Once with no rings or piston locks for mock-up, clearance checking, deck height measurements, crank index check, rod side clearance, thrust clearance, etc. Then I gapped the rings and put the pistons in, but noticed that I may have not had the rings square in the bore when gaping them, so I pulled it apart and double checked, and found two rings that were just a bit tight on the gap when squared correctly. I also re-verified the rings were installed correctly (not upside down) and put the short block back together again for the third time. I did degree the cam with just one piston installed (no rings) so I can spin the engine easy. I checked the #1 and #6 cam timing. It looks like #6 is slightly advanced 1/2 degree from #1. I think to account for cam twist?
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Re: Consistency... Engine Build question
[Re: Locomotion]
#1128589
12/08/11 10:30 PM
12/08/11 10:30 PM
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Joined: Jan 2003
Posts: 19,304 Las Vegas
Al_Alguire
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 19,304
Las Vegas
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Well you have driven a car that has a lot of attention to detail in it and a lot of laps down the track. If you build it right, pay attention to the small things you will have a good base to work from. However I dont think there is a lot to be found with consistency on engine building. That comes from having a good working overall combination that is well sorted out and predictable in what it will do, and a driver that is also doing the right things. It takes time to build consistency to win at a National, Divisional or even at a consistent level at local bracket races. There is no secret engine tricks to consistency no bracket racing. It is about having information, knowing how to use that information and being able to repeat, as a driver and the car as a whole. IMO there is plenty more you can do wrong than anything you will do in building an engfine. As long as the engine is built correctly that is all you need to worry about. Dont overthink this stuff, there is no one secrect magic bullet to being able to be consistent on a regualr basis. It comes down to hard work, dedication and of course lots of $$$$$$
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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