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Marv D · 02-14-2012, 10:39 AM

Yeah I think 'wastgate' was an improper term,, blowers have a similar spring loaded contraption at teh base of the blower to relieve pressure,, can't remember what they call it in the street application, in the big dawgs it was called the burst panel.

Abad84,, I don't know much about blower motors, but this i do know BLOWN MORTORS LOVE INITIAL ADVANCE. Get someone who knows the ignition demands of the blown gas motor to set up your distributor before you do more damage. A typical blown gas street combo will like 15-20+ INITIAL, and have a short mechanical advance of 10-12°

You probably also bent a pushrod and or fractred a rocker in that little backfire. Check everythign THOUROUGHLY before you just assume it's onlya broken valve spring.

The carbs for a blower motor are a little different tune also. You want something to nearly DROWN the motor with accelerator pumps, and run PIG PFHAT ,, then tune down from there. Starting on the other end of the spectrum is asking for bent rods, broken parts and .....well,,,, Here's a scenario a buddy went through with a 671 blown 454 with a pair of CarbShop 750's supposedly set up for a blower.
First he was amazed at the headers woudl GLOW in the dark at idle. (cause:, too little advance and the fuel was burning in the header tube,, trying it's best to take the exhaust vale out)
Every time he stuck his foot in it , it would backfire and pop out the spring loaded burst panel. (cause:, stock street type squirters in this "blower carb" with stupid 30cc accelerator pumps)

Can was a hydraulic flat tappet Comp Cam 'street' cam with the springs the cam called for (STUPID MOVE with 6-8psi of boost!!!, boost comes up and the door couldn't close fast enough with the soft springs)

Results,, after 2-3 months of tinkering and trying to blow the thing up,, he succedded. He stuffed his foot in it, it poped, broke a chunk of the cam out and it fell into the rotating assembly. Total engine destruction.

GET SOMEONE THAT IS EXPERT IN TUNING A BLOWER MOTOR before you follow his footsteps.

just my 2¢, wish you luck

02-14-2012, 10:39 AM	#14
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	Re: 355 Blower eng. break in time n oil type q Yeah I think 'wastgate' was an improper term,, blowers have a similar spring loaded contraption at teh base of the blower to relieve pressure,, can't remember what they call it in the street application, in the big dawgs it was called the burst panel. Abad84,, I don't know much about blower motors, but this i do know BLOWN MORTORS LOVE INITIAL ADVANCE. Get someone who knows the ignition demands of the blown gas motor to set up your distributor before you do more damage. A typical blown gas street combo will like 15-20+ INITIAL, and have a short mechanical advance of 10-12° You probably also bent a pushrod and or fractred a rocker in that little backfire. Check everythign THOUROUGHLY before you just assume it's onlya broken valve spring. The carbs for a blower motor are a little different tune also. You want something to nearly DROWN the motor with accelerator pumps, and run PIG PFHAT ,, then tune down from there. Starting on the other end of the spectrum is asking for bent rods, broken parts and .....well,,,, Here's a scenario a buddy went through with a 671 blown 454 with a pair of CarbShop 750's supposedly set up for a blower. First he was amazed at the headers woudl GLOW in the dark at idle. (cause:, too little advance and the fuel was burning in the header tube,, trying it's best to take the exhaust vale out) Every time he stuck his foot in it , it would backfire and pop out the spring loaded burst panel. (cause:, stock street type squirters in this "blower carb" with stupid 30cc accelerator pumps) Can was a hydraulic flat tappet Comp Cam 'street' cam with the springs the cam called for (STUPID MOVE with 6-8psi of boost!!!, boost comes up and the door couldn't close fast enough with the soft springs) Results,, after 2-3 months of tinkering and trying to blow the thing up,, he succedded. He stuffed his foot in it, it poped, broke a chunk of the cam out and it fell into the rotating assembly. Total engine destruction. GET SOMEONE THAT IS EXPERT IN TUNING A BLOWER MOTOR before you follow his footsteps. just my 2¢, wish you luck __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.