Restrictor plates…are they
Thread Starter
Melting Slicks
Joined: May 2005
Posts: 3,461
Likes: 161
From: Las Vegas Nevada
St. Jude Donor '08
Restrictor plates…are they
safe when using them to restrict airflow at higher rpms? I am thinking of using a restictor plate to prevent the boost from going over 6 psi on my procharged Vette. Without anything, it will go as high as 11psi at 6,500rpm. Will this cause any harm to my motor or supercharger, or should I pulley up? Also, if I go from a 3.85” pulley to a 4.1”, do I need a retune?
Clayton
Clayton
Melting Slicks
Joined: Apr 2003
Posts: 2,285
Likes: 16
From: Nashville TN
Restrictor plates definitely work. We did a lot of experimenting with different size plats when I went down in pulley size. Without the restrictor my car see 16 psi and 750 rwhp, with the restrictor I see 13 psi and 650 rwhp. The best part is I lost nothing on the bottom and mid range. The airflow just gets limited at the top end. In my case above about 5500 RPMs. I would say go with the smaller pulley and run a restrictor.
Thread Starter
Melting Slicks
Joined: May 2005
Posts: 3,461
Likes: 161
From: Las Vegas Nevada
St. Jude Donor '08
Restrictor plates definitely work. We did a lot of experimenting with different size plats when I went down in pulley size. Without the restrictor my car see 16 psi and 750 rwhp, with the restrictor I see 13 psi and 650 rwhp. The best part is I lost nothing on the bottom and mid range. The airflow just gets limited at the top end. In my case above about 5500 RPMs. I would say go with the smaller pulley and run a restrictor.
Just want to make sure it is not hurting my engine by restricting the airflow.Clayton
Race Director
Joined: May 2003
Posts: 12,725
Likes: 14
From: ECS : WTF did you break now and HTF did you break it this time
now if you had an overdrive crank pulley and a tiny blower pulley on a motor cammed for low end and midrange.....then I could see limiting things based on RPM
Melting Slicks
Joined: Nov 2006
Posts: 2,836
Likes: 8
From: Still the Fastest (still running) Stock Bottom End Blown LS1/ 2010 ECS CC 10.50 CHAMP Hamilton, NJ
So I would have to set the limiter at 4500 and shift at what? 4500.
Thanks, but I will stick to the restrictor, it makes thing more consistant, and it has held my stock bottom together for a long time.
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Melting Slicks
Joined: Mar 2004
Posts: 3,472
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From: Lake Ozark, MO
I'd be careful with those boost levels (11psi) in a stock LS1....rings in the rear cylinder will begin to self destruct because of the added heat. I just destroyed # 7 cyl. (of course) with 7 psi. Motor was stock with 65K miles and not run "that" hard that much....
Drifting
Joined: Mar 2006
Posts: 1,872
Likes: 7
From: Richmond VA
I could be wrong, but I believe it is difficult to get over 10# with a P1 and a 6 rib belt. Mine slips a little bit and just over 9#. To get 11# on mine, I'd probably have to go to a 3.5" or smaller and then it would really slip.