Dynoed Hawk 525 today, had a problem...
04-25-2010 | 09:10 PM
#21
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Joined: Mar 2008
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From: Vancouver BC
The original intake was badly corroded at the Tstat housing which seems to be very common. I replaced it with an oval intake and the factory blower with stock pulleys.
04-26-2010 | 12:25 AM
#22
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From: Omaha/LOTO
The Hawk 525's were Merc 420's with the 177 blower. Not sure if they have a rev limiter or not. Most likely they do, but it should not kick in until at least 5300-5400rpms if it is the stock 420 ignition. when it kicks in, it is more like an engine miss, but it should not create a carb backfire. I did some prop testing on my 525SC Pantera and hit the rev limiter a few times. It really was not that significant. Just felt like a slight misfire for a split second.
04-26-2010 | 08:20 AM
#24
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From: Vancouver BC
I've hit the limiter on the dyno a few times and it's pretty smooth. For it to be shooting through the carb, assuming your timing and air fuel was in range, it's got to be misfiring. The modules are very ground sensitive and I've definitely seen issues in the past from a bad ground. Hope it works out for ya! 
Last edited by HaxbySpeed; 04-26-2010 at 08:22 AM.
05-20-2010 | 06:21 PM
#25
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From: blue point,ny
Dynoed first engine today. With Mercury Thunderbolt ignition on, engine would rev up to 5000 RPM, the we would lose ignition.(back fire through carb) Did this 3 times in a row. New coil, sensor,cap and rotor from mercury. Does this system have a rev limiter in it??? How about in the module? Its a v8 module.... Put an MSD distributor in with a 7AL box, and engine ran perfect! Right to 5700 RPM not prob. Anyone have any answers? Need to figure this out by Monday cause engine is coming off dyno Monday afternoon.
05-23-2010 | 04:59 PM
#26
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From: blue point,ny
[QUOTE=MILD THUNDER;3095129]
That sounds good man. I have the same setup. 454, dart aluminum heads, 741 roller cams, 177 blowers, stock pulleys. They make nice power for some little motors! Compression on the hawk 525's were around 8.5:1 i think. Which is where i am with mine. I use a msd ignition.
Im sure it could have been something like a bad pickup in the merc distributor, etc.
What kind of power are your motors making? Just curious because I am picking up a pair off 525 hawk motors with intercoolers and putting them on my 454 mags.
Wayne
That sounds good man. I have the same setup. 454, dart aluminum heads, 741 roller cams, 177 blowers, stock pulleys. They make nice power for some little motors! Compression on the hawk 525's were around 8.5:1 i think. Which is where i am with mine. I use a msd ignition.
Im sure it could have been something like a bad pickup in the merc distributor, etc.
Wayne
