TBucket Engine Project (Dart SHP)

I just did some research, Rick your cam has 69 degrees of overlap. I believe fattening the AFR to 14.5 will help with your problem. The durations are 232int/240exh @ .050, range 2400-6000 per summit
 
If a fuel pump is weak with low volume and pressure output it will cause leaner than expected AFR while driving.
A plugged fuel filter will do the same.
I have not had great experiences with Holley Fuel pumps.
Start off strong. They get worn out and tired.
Economic design.
I like Mallory Comp Fuel pumps. 110 -140- 60Fi -110Fi.
Gear Rotor design and the Electric motor is more Robust. Ball bearing on lower Drive base.
Holley does not have it.
Holley Blue is taxed on.limit right at 450-500 Hp.
Will be verified with an Autometer Pro Comp Fuel pressure guage seen in Drivers cockpit driving at speed.

Rick Wideband tuned prior.
He was supposed to to upgrade and replace all of fuel system last winter into early 2016.
Didn't get done.
I don't recall Ricks Crower cam being that Hot.
Engine was built for street use.
Long before Current HP Race & 1/4 mile race started by The H cars.
 
Its also the #1 cause of Blown Hotrod & Racing engines.
Substandard Fuel pumps & Fuel systems.
Can not ever be verified accurate driving or racing at speed without a Remote mounted Autometer fuel pressure guage in the drivers cockpit.
I have it on my Pontiac Grand Prix.
WOT @ 120 mph I have 7 psi.
On my TA the Autometer Pro Comp Liquid Filled Fuel pressure guage is mounted on the drivers lower corner windshield base.
Its more important than the Tachometer.
Fuel Pressure readings & oil pressure readings are #1 to watch.
 
the guys have a point, best power and in many cases durability, is generally found at nearer 12.7:1 f/a ratio, I don,t ever remember your engine getting near that lean while we discussed getting it tuned up?
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well I'll assume you previously read the links on engine building,and quench, and you have at least tried to build a well balanced combo with reasonable quench,and tried to match the cam duration and lsa to the engines compression and intended power range, and you selected a fairly well matched cam timing and reasonable compression, but at this point in the tuning ,your still having indications your getting into detonation.
keep in mind that keeping reasonably consistent and as low as practicable , combustion chamber temps are a huge factor in avoiding detonation issues, having an auxiliary oil cooler and a trans fluid cooler with a powered fan, and the proper fuel/air ratio and ignition advance curve along with matching your cars engine dynamic compression ratio to the available fuel octane can go a long way toward avoiding detonation issu
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so what your trying to do is reduce combustion chamber temps,increase your fuels octane, reduce your fuel/air temperatures, or reduce your combustion chamber pressure or speed up combustion
http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/
 
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Sorry I've been a recluse lately, I don't mean to, just happens to me sometimes lately.

I do have some carb tests to report, but I want to test further before reporting. Leaving for another
6 hour drive on Wednesday 8/7/16, so I have to figure out my detonation problems before then.
 
Yes we missed your input here!
from a pragmatic view, well you know the quick and effective cure even now, you simply fill up with higher octane fuel until you work out the current problem, the second step would obviously be to re-jet the carburetor richer and back off the ignition advance curve, a couple degrees until you have the time and equipment to test more in detail.
obviously the cost of higher octane fuel is much cheaper than engine damage and re-jetting the carb, richer on both the primary and especially the secondary helps reduce detonation.
keep in mind fuel octane changes during different times of the year and bye brands, so its never consistent.
 
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I agree, backing the advance curve down to around 2900-3000 @ 33-34 degrees and richer pri and sec jetting would bring your AFR back to normal, I think it would solve the detonation problem.
 
thats one of the benefits to living in florida , "winter" drags on for an amusing 48-72 hours,
most years when you get to see the native floridians panic when the outside temps drop into the high 30s-to the low 40F range.
the last time I saw snow here it melted within 15 minutes of hitting the ground and that was back in the late 1970s
 
Any progress Rick?
I don't know what the weather is like now in OK, but here in CT
we just had a blizzard after a record warm February.

That's right, I have to send a box of snow to Grumpy.:rolleyes:
 
No progress, but I did get it out yesterday for a nice long drive. It was in the 80°s and today is suppose to be in the 90°s. I'll take some snow, we could use it today!!!
 
well, its been quite a while now!
any new progress on the t-bucket Rick?
 
Sorry I have not answered sooner, but I went to a NTBA event for TBuckets. Got back and two days later I had to make a trip to Houston for a funeral and didn’t get back until last Friday (5/12)evening. Then there was Mother’s Day, so Saturday was getting ready and Sunday was a no go.

Like I mentioned above, I went to an all Tbucket event in Nazareth TX, about ½ way between Amarillo and Lubbock. Last summer I had changed the main jets to .075 which lowered my MPG to 18.0 on this last trip. I didn’t notice any detonation on this trip, but the ambient temperature was in the 60’s F, so the temp certainly helped with detonation. I may lean it out to .073 and see how that does when the temps get higher.

Here are a few pics from the NTBA event.

The red TBucket below has an all Stainless Steel frame front axle, suspension links, headers, radiator grill and fan shroud.

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