Blow through 5.3 boost spike help
Thread Starter
Launching!
Joined: Jun 2012
Posts: 249
Likes: 36
From: Pennsylvania
Blow through 5.3 boost spike help As the title states I'm having a boost spike issue. Just got the car running a few months ago and wanted to turn it up a little bit. Ran it with the 7-8 pound spring with out issue. I then bought an 11 pound spring and started having this issues. Under full boost it is spiking to 16+ psi. Only thing I changed was the spring and took out a little more timing. I checked everything over and found all the fittings are tight and I replaced the line going from waste gate to the intake. Second fitting on side of wastegate is plugged and tight. On the wastegate I have the top fitting un plugged to the atmosphere and the side fitting plumbed into the unported fitting on the carb. Running out of ideas any help is appreciated.
Car is a 1947 ford coupe under 3k with me in it
Stock 5.3, cam, valve springs, hardened push rods
Vic Jr with CSU blow through carb
3800 stall th350
On3 78/75 with on3 44mm wastegate
Car is a 1947 ford coupe under 3k with me in it
Stock 5.3, cam, valve springs, hardened push rods
Vic Jr with CSU blow through carb
3800 stall th350
On3 78/75 with on3 44mm wastegate
As the title states I'm having a boost spike issue. Just got the car running a few months ago and wanted to turn it up a little bit. Ran it with the 7-8 pound spring with out issue. I then bought an 11 pound spring and started having this issues. Under full boost it is spiking to 16+ psi. Only thing I changed was the spring and took out a little more timing. I checked everything over and found all the fittings are tight and I replaced the line going from waste gate to the intake. Second fitting on side of wastegate is plugged and tight. On the wastegate I have the top fitting un plugged to the atmosphere and the side fitting plumbed into the unported fitting on the carb. Running out of ideas any help is appreciated.
Car is a 1947 ford coupe under 3k with me in it
Stock 5.3, cam, valve springs, hardened push rods
Vic Jr with CSU blow through carb
3800 stall th350
On3 78/75 with on3 44mm wastegate
Car is a 1947 ford coupe under 3k with me in it
Stock 5.3, cam, valve springs, hardened push rods
Vic Jr with CSU blow through carb
3800 stall th350
On3 78/75 with on3 44mm wastegate
Put the lighter spring back in and use a boost controller of some sort to hit your desired boost. You can easily make 16+lbs on a 7-8lb spring.
Thread Starter
Launching!
Joined: Jun 2012
Posts: 249
Likes: 36
From: Pennsylvania
It's an on3 44mm wastegate. When I took it apart to put the 7 pound spring in I looked at the diaphram gasket and it looked ok but I will try to put air to it and see if it is sealed once I get off work
