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Discussion Starter #1 (Edited)
Never had a blower motor before and I'm a couple weeks away from firing this new motor for the first time. Motor is a Dart M block 565" with a Callies crank, Oliver MX rods, JE 8.8:1 blower pistons, 345cc Dart Pro 1 heads, and a Herbert CB6E solid roller at 715/730 and Dur @ .050 Int-Exh: 265/280. Just converting the heads to a shaft setup right now and should have the new push rods in there tomorrow.

Blower is an 8-71 with 54 lower and 50 upper pulley for 8lbs of boost at sea level running 8% OVER. I'm at 5500' corrected elevation so I'm thinking this thing will only make about 4-5 lbs at this elevation and compression should factor in around 8:1 by the time all is said and done with the corrections. Entire setup is new and I'm topping it with AED 850HO modified blower carbs that were specifically built for this motor. Not sure what plug to run at the moment, but the ignition of choice is an MSD 6AL-2 programmable with a pro billet distributor and a MAP sensor for setup of the boost retard feature on the MSD.

I haven't programmed the MSD as of yet so if anyone has any tips or suggestions for timing control at first startup, and where it should be at when running I would benfit from others experience. I have a good friend who's gonna be around when I fire it and he's great at tuning carbs, but has only done a couple blower motors over the years. Open to any feedback from those in the know.

Tips, Do's and Don'ts are much appreciated.

G.
 

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I WOULD RUN 3932 OR VPOWER 10 PLUG SOMEWHERE AROUND 27-28 TOTAL TIMING THEN TAKE OUT 1.5 DEGREES PER POUND TO START . LET YOU PLUGS / WIDEBAND TALK TO YOU. THIS SHOULD BE A GOOD SAFE PLACE TO START.
 

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I had a roots blown bbc at 5lbs and made 20 dyno pulls testing timing.

We found 80 horsepower between "really safe" timing and the optimum, which turned out to be 31 degrees. At 32 or 33 degrees power dropped noticeably.

I also had Boost Timing Master, MSD 6, etc. In the end the best power and simplest was just plain old locked out timing......like they've been doing for 50 years. The MSD had a start retard feature which helped cranking.

An overdriven roots blower makes almost full boost, almost instantly so special curves and such may not be of any advantage.

You've got aluminum heads which might allow more "safe" experimentation than my old-school iron head stuff. The 10 NGK's are plenty safe as well. We ran 9's.

Since your carbs are from a custom shop I assume they are boost-reference power valves or no power valves and just jetted for competition, and all kinds of other tricks....so you're probably good there.

Just My Humble Opinion.
 

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Discussion Starter #5
Thanks for the info guys. I'll have to look at it and see how the boost comes on but was going to map it to pull 1 degree out per lb of boost above 3 lbs but if it comes on faster like you say I'll likely lock it down. Was thinking of starting around 28 degrees but might bump that to 30 and see if I can use the boost retard to back it down to 28 all in @ full boost and try that? I was told that AED builds a really nice carb on a 4150 platform.

I'll try the 10 plugs and check them after it's been running to get a read from them. Yes the AED carbs were built for a blower. They're boost referenced and the metering blocks were worked over as well and should flow equivalent to 900cfm carbs. Thay are supposed to be within 1 jet size of optimal for this combo at altitude.

Thanks again...
 

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You might call Don Hampton (Hampton Blowers...google it). He's still alive, driving drag cars, etc. He's been doing it a long, long, time. He will not try to sell you on anything complicated or unproven....he's a good guy and will talk to you even if you don't have a Hampton blower, if you keep it short.

So will Craig at BDS.........also been at for years. He freely embraces cutting edge technology BUT only if it has gains for your setup. The beauty of your setup is it's simplicity and that it's been done over and over since about 1965.

Give those guys a call.
 

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Never had a blower motor before and I'm a couple weeks away from firing this new motor for the first time. Motor is a Dart M block 565" with a Callies crank, Oliver MX rods, JE 8.8:1 blower pistons, 345cc Dart Pro 1 heads, and a Herbert CB6E solid roller at 715/730 and Dur @ .050 Int-Exh: 265/280. Just converting the heads to a shaft setup right now and should have the new push rods in there tomorrow.

Blower is an 8-71 with 54 lower and 50 upper pulley for 8lbs of boost at sea level running 8% OVER. I'm at 5500' corrected elevation so I'm thinking this thing will only make about 4-5 lbs at this elevation and compression should factor in around 8:1 by the time all is said and done with the corrections. Entire setup is new and I'm topping it with AED 850HO modified blower carbs that were specifically built for this motor. Not sure what plug to run at the moment, but the ignition of choice is an MSD 6AL-2 programmable with a pro billet distributor and a MAP sensor for setup of the boost retard feature on the MSD.

I haven't programmed the MSD as of yet so if anyone has any tips or suggestions for timing control at first startup, and where it should be at when running I would benfit from others experience. I have a good friend who's gonna be around when I fire it and he's great at tuning carbs, but has only done a couple blower motors over the years. Open to any feedback from those in the know.

Tips, Do's and Don'ts are much appreciated.

G.
With no compression and no boost and that terrible altitude ,i wouldnt be afraid of 30 deg timing and no retard at all.We have run combos like that with 34 deg timing but i wouldnt start there.
 

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Never had a blower motor before and I'm a couple weeks away from firing this new motor for the first time. Motor is a Dart M block 565" with a Callies crank, Oliver MX rods, JE 8.8:1 blower pistons, 345cc Dart Pro 1 heads, and a Herbert CB6E solid roller at 715/730 and Dur @ .050 Int-Exh: 265/280. Just converting the heads to a shaft setup right now and should have the new push rods in there tomorrow.

Blower is an 8-71 with 54 lower and 50 upper pulley for 8lbs of boost at sea level running 8% OVER. I'm at 5500' corrected elevation so I'm thinking this thing will only make about 4-5 lbs at this elevation and compression should factor in around 8:1 by the time all is said and done with the corrections. Entire setup is new and I'm topping it with AED 850HO modified blower carbs that were specifically built for this motor. Not sure what plug to run at the moment, but the ignition of choice is an MSD 6AL-2 programmable with a pro billet distributor and a MAP sensor for setup of the boost retard feature on the MSD.

I haven't programmed the MSD as of yet so if anyone has any tips or suggestions for timing control at first startup, and where it should be at when running I would benfit from others experience. I have a good friend who's gonna be around when I fire it and he's great at tuning carbs, but has only done a couple blower motors over the years. Open to any feedback from those in the know.

Tips, Do's and Don'ts are much appreciated.

G.
can i ask why the little carbs on this much engine?
 

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Discussion Starter #10
Vinny, this was built as a street motor that will probably see 10%-20% track time. Drive-ability was first and foremost and both AED and Pro Systems had both suggested a custom carb built on a 4150. I know I could have went with Dominators but was told the 4150's are better suited for street use and everyday cruising. If I was racing it more, I'd have gone bigger and trust the work AED did on the carbs should make the cut for what I plan on doing with it.
 

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Discussion Starter #11
With no compression and no boost and that terrible altitude ,i wouldnt be afraid of 30 deg timing and no retard at all.We have run combos like that with 34 deg timing but i wouldnt start there.
The altitude in Calgary is 3600' but the correction factor has it measuring over 5500' in the summer. If drag racing becomes as much fun as I know it can be, then I may run the car in Ashcroft and Mission where elevation is close to sea level. Swapping the pulleys around should then give me 8lbs under driven and better compression.

The reality here is that it will still make a fun street motor. If I need more, then I'll make some changes. Probably should have went with a 10-71 but couldn't pass up the deal on this blower at the time. Gotta live with it now I guess.
 

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I would think 30 degrees without pulling any should be fine to start with. If your pulling start even higher so it ends up around 30. Altitude sucks... I know as our density altitude during the summer is ~8400'.
 

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A number #10 plug is way to cold , #8 plug is what you want. With that amount of boost you will need no timing pulled and start with 30degrees of timing.
 

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Discussion Starter #16 (Edited)
For those who like pictures,

Here's a couple pics of the valve train that was installed yesterday as my good friend Mike came by to help me out installing the Crower setup. Should be a lot more stable now than with that big ugly Dart girdle that was on there before. (lol)





 

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The altitude in Calgary is 3600' but the correction factor has it measuring over 5500' in the summer. If drag racing becomes as much fun as I know it can be, then I may run the car in Ashcroft and Mission where elevation is close to sea level. Swapping the pulleys around should then give me 8lbs under driven and better compression.

The reality here is that it will still make a fun street motor. If I need more, then I'll make some changes. Probably should have went with a 10-71 but couldn't pass up the deal on this blower at the time. Gotta live with it now I guess.
Sounds good bud ,we have a lot of bad air in midwest also.Have fun let us know how it goes.Starting with those carbs will get your feet wet,and on the right path .
 

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One more thing pay attention to rocker clearence in those valve covers.You can feel valve covers and feel if hitting when it first fires.I have saw guys kick pushrods ,trash lifters and cam with rockers hitting in covers .In a matter of seconds it will mark them.Try and push covers up towards intake when you tighten them..
 

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You should measure your dist. pad to top of oil groove on the dist.Then measure the pad on intake to top of oil hole galley in block .Sometimes blower intakes have the dist pad a little high or low.This should be checked on any new engine...
 
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