new engine combo, no blower boost
09-16-2008, 09:48 PM
#11
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I talked to weiand also, they were concerned about my flame arrester, which is a 8"x2" eddie marine s/s, the carb sitting in a open scoop with good airflow, when running did not have back seat in so blower drive was right there open, no sign of belt slip, and almost no whine from the blower either..Rob
09-16-2008, 10:16 PM
#12
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The guys are right - that blowers really really small.
As a point of reference a B&M 250 was still to small on my 383.
Even if you get boost out of it the intake air will be so hot as to bring on detonation. spin it any faster and youll start chuffing air and slipping as that setup usually uses a ribbed vs cogged belt.
DO yourself a favor and step up the blower to lysholm/whipple type deal-or at the very minimum a 6-71 - Youll be a lot happier.
Uncle Dave
Laveycraft 2750 Ilmor 710
Laveycraft 20.8 Sebring 406 SB
Fleetwod nitrous toy hauler
Yamaha raptor 700/Kawi KFX 450
Nissan Titan
As a point of reference a B&M 250 was still to small on my 383.
Even if you get boost out of it the intake air will be so hot as to bring on detonation. spin it any faster and youll start chuffing air and slipping as that setup usually uses a ribbed vs cogged belt.
DO yourself a favor and step up the blower to lysholm/whipple type deal-or at the very minimum a 6-71 - Youll be a lot happier.
Uncle Dave
Laveycraft 2750 Ilmor 710
Laveycraft 20.8 Sebring 406 SB
Fleetwod nitrous toy hauler
Yamaha raptor 700/Kawi KFX 450
Nissan Titan
09-17-2008, 01:19 AM
#13
Charter Member # 55
Charter Member
The blower is small, but he should still be seeing some boost. He should be seeing 3-4lbs.
A stock 525SC uses a 2:1 overdriven ratio on 454ci and makes 5.5# of boost.
That blower should be whining a LOT at WOT. My guess is the rotors are bad in the blower.
A stock 525SC uses a 2:1 overdriven ratio on 454ci and makes 5.5# of boost.
That blower should be whining a LOT at WOT. My guess is the rotors are bad in the blower.
09-17-2008, 07:47 AM
#15
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call nickerson perf. about carb. size even a holley tech. when given all the info will say you need a larger cfm also look at at there websit under catalogs and look at there charts for blower ratios on stock marine eng. and I think you will find your answers even if your blower is in great cond. you need to change pulleys
09-17-2008, 08:13 AM
#16
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Given hes reading vacuum Its likely not the gauge. with a small pulley it should give him at least 4 pounds but it will sound like a million bees inside the hatch.
Nickerson can help -(they did my original carb) he's is undercarbed but not drastcially- although the stock carb has a lousy signal at medium to low openings a demon would wake it up in the midrange.
He could likely need a teflon seal replacement. - pretty sure that blower uses them, and while its off the top- at minimum put an intercooler in there, or buy a biggerblower.
Uncle Dave
Laveycraft 2750 Ilmor 710
Laveycraft 20.8 Sebring 406 SB
Fleetwood nitrous toy hauler
Yamaha raptor 700/Kawi KFX 450
Nissan Titan
Nickerson can help -(they did my original carb) he's is undercarbed but not drastcially- although the stock carb has a lousy signal at medium to low openings a demon would wake it up in the midrange.
He could likely need a teflon seal replacement. - pretty sure that blower uses them, and while its off the top- at minimum put an intercooler in there, or buy a biggerblower.
Uncle Dave
Laveycraft 2750 Ilmor 710
Laveycraft 20.8 Sebring 406 SB
Fleetwood nitrous toy hauler
Yamaha raptor 700/Kawi KFX 450
Nissan Titan
09-17-2008, 08:22 AM
#17
Registered User
Spinning a blower at 2x + overdrive is certainly one way to shorten the life.
On 500 cid, an 8-71 running at about 0.94 under should be ideal. Little added heat and still enough rotor speed to prevent loss of atomization. Use a set of Holley 750 blower carbs with boost referencing.
On 500 cid, an 8-71 running at about 0.94 under should be ideal. Little added heat and still enough rotor speed to prevent loss of atomization. Use a set of Holley 750 blower carbs with boost referencing.
09-17-2008, 12:09 PM
#19
Charter Member # 55
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Spinning a blower at 2x + overdrive is certainly one way to shorten the life.
On 500 cid, an 8-71 running at about 0.94 under should be ideal. Little added heat and still enough rotor speed to prevent loss of atomization. Use a set of Holley 750 blower carbs with boost referencing.
On 500 cid, an 8-71 running at about 0.94 under should be ideal. Little added heat and still enough rotor speed to prevent loss of atomization. Use a set of Holley 750 blower carbs with boost referencing.
The 177 was designed to be spun that fast. It has a recommended max rpm is around 13000rpms. The problem with spinning it faster is the heat it creates.
