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489 BBC TIMING
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DRR Trophy
Picture of R.BOLDEN
posted
I purchased a race car with a 489 BBC, I checked the timing and its on 40 degrees. I was just wondering if anyone else runs that much timing. This car ran consistent and done well. The motor has a 2927 intake,1050 dominator with 2"spacer,aluminum pro comp heads that have been worked,dome arp pistons,722/722 lunati roller cam,and I was told they had to move the cam around to get valve to piston clearance and that it had a lot of compression.this is in a 3100# plus car that runs 1/8 mile with a powerglide and 488 gear
 
Posts: 9 | Location: morristown,tn | Registered: October 28, 2012Reply With QuoteReport This Post
DRR Pro
Picture of HS professor
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I run 38-40 degrees on all my big blocks with a big dome on gas. If running alky, 35 degrees seemed to work well. They all start easily and don't detonate on 110 octane, These are 454-468 stuff with off the shelf pistons, so compression is never more than a true 12.0.
 
Posts: 1421 | Location: Monroe twp nj | Registered: December 05, 2005Reply With QuoteReport This Post
DRR Trophy
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Yep, not uncommon at all. I don’t think many try more timing based on what they’ve heard it needs. I had a 15 to 1, 615 BBC with old conventional heads long ago that ran best at 40* on gas. It picked up like .04 and around 1.5 mph going up from 38* IIRC, running 7.40’s at 180. I didn't expect it to like it.
 
Posts: 27 | Location: Vancouver, WA. | Registered: August 17, 2004Reply With QuoteReport This Post
DRR Pro
Picture of RacerVX54
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38-40


"Just Shut Up and Race"

Brian Martin
Martin Racing
5.66 @121.55
 
Posts: 1385 | Location: Va.Beach .Va | Registered: August 03, 2005Reply With QuoteReport This Post
DRR Sportsman
Picture of FootbrakeJim
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OP did not mention what fuel it burns, so I assume gas. My 468 with big domes liked 40* best on race gas, not a lot of diff from 38* though, like .01-.02 quicker, maybe 0.5-1 MPH faster, so I went with the safer 38 in case of fuel quality variances, etc.
On methanol, it likes 36* best. Tested at 2* increments, from 32-40.


Dan "Jim" Moore
Much too young to feel this damn old!!
 
Posts: 1032 | Location: Farmersville, TX  | Registered: December 05, 2002Reply With QuoteReport This Post
DRR S/Pro
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quote:
Originally posted by R.BOLDEN:
I purchased a race car with a 489 BBC, I checked the timing and its on 40 degrees. I was just wondering if anyone else runs that much timing. This car ran consistent and done well. The motor has a 2927 intake,1050 dominator with 2"spacer,aluminum pro comp heads that have been worked,dome arp pistons,722/722 lunati roller cam,and I was told they had to move the cam around to get valve to piston clearance and that it had a lot of compression.this is in a 3100# plus car that runs 1/8 mile with a powerglide and 488 gear


Assuming the pointer is correct for that motor with open chambered heads and a decent domed piston 38 to 42 is common.
 
Posts: 2145 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR Trophy
Picture of R.BOLDEN
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Yes I checked the pointer and it is correct,the previous owner run 110 race gas,and I am going to run Avgas from the airport. I'm shifting it on 6600 and going through no more than that,and it has #8 ngk plugs in it,he had a Autolite 3933 which is like a #9 ngk.i normally run #7 ngk in all my small blocks, but this is my first bbc
 
Posts: 9 | Location: morristown,tn | Registered: October 28, 2012Reply With QuoteReport This Post



DRR Pro
Picture of chasracer
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You could go to the colder #9 NGK and bump the timing a couple of degrees to see if it likes it.
 
Posts: 1135 | Location: The problem is not the problem. The problem is your attitude about the problem. Savvy?” ~~ Captain Jack Sparrow ~~ | Registered: August 21, 2000Reply With QuoteReport This Post
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