Join Date: Mar 2001
Location: Regina, Saskatchewan, Canada, Earth
I have a brand new Street Avenger 750 on my newly assembled 355, 10.32:1 comp., Edelbrock 64cc Alum heads, Preformer RPM Air Gap,280H comp Cam. So far the engine has only seen the dyno(406hp 410 tq) so should see 420 of each once rings are seated in.
My concern is we had trouble getting the secondaries to fully open. We went from the original silver spring to the yellow spring to shortening the yellow to stretching the shortened yellow (pulled it inside out) to get the best results. But still not completely opening. There was no obstruction in the linkage or gasket interferance that I could see.
Now I have talked to my speed shop guy and he said some guys are doing this: If has a check ball in place in the secondary pot they are removing it. If no check ball, but a small hole instead, they are drilling it back out to 1/4 inch. Wouldn't this just cause faster rate of opening or would it help pull them open further? I suspect I would have to go back to a heavier spring to counteract the faster opening. Kind of 2 steps ahead and 1 step backward. Is this ball or small hole not the backfire protection they talk about?
We also talked about the tiny ports in the actual venturies, but once fooling around with them the damage is permanent and I don't want to go there.
Do you have any other hints as to what the problem could be? Or is this situation just the carb only giving what the engine needs or is calling for?
Sorry for all the questions but the motor is now in the car and I am just waiting for my rad to be finished (going from a 3 to a 4 core & 2" wider). Then I plan on running it a bit (can hardly wait). This is in a '68 Camaro, 3000 stall, with 4.11. It will mostly be on the street but will hit the track to see what it is capeable of, when unleashed. Thanks again for any info you can provide. Barry from Regina, Sask. Canada