TCCoA Forums banner

FR500 Intake Manifold

4K views 3 replies 2 participants last post by  Grog6 
#1 ·
I have some questions about this intake that I have and I'm looking to see if anyone else has been exposed to one of these gems. I did not know there was an issue until we fired her up.

1. Below 3500 RPM is it normal for the IMRC plates to rattle? Actually the rods are loose and causes the plates to rattle when they are closed.
2. Is there a bushing kit to quite this snake?
3. I notice there is adjustment screws for the plates. How are the to be set?

My dad had a Lincoln Aviator. they were very quiet. I'm sure they failed closed, causing top end to suffer when that happened.
Any help would be appreciated

Read ya later, Nick
 

Attachments

See less See more
1
#2 · (Edited)
First off, those are CMCV's, not IMRCs.

IMRC's were on B-heads.

They change runner length from long to short; there the imrc's open up the secondary ports on the b-heads.

I did some looking around, and that's normal for those intakes. It's flutter in those plates, as you said.

I didn't see anything about adjustment.

Someone said opening them at 2000 rpms help, and someone else said the torque/hp with the long runners suck, but IDK.

I did learn something cool, na svt's name. :)


Here's some posts I found; I've been looking into that intake. :)

https://forums.corral.net/forums/svt-dohc/1336066-fr500-intake-long-runner-rattle.html
 
#3 · (Edited)
CMVC's is an acronym for what? I know IMRC is intake manifold runner control. Long runner or short runner, I plead ignorance.

Yesterday we had her on the dyno and found at 3500 RPM there was a dip of 20-15 horse power, a lower RPM setting would yield more loss, so we increased the RPM window to 4500, then 5000 and settling at 4700RPM for the plates to open to get the best line.

Thank you Grog6, for finding out the info about the FR500 intake. I didn't have anything before now.

Read ya later,Nick
 
#4 ·
I swapped two letters, I corrected it above.

They're Charge Motion Control Valves. (or vanes)

Instead of adding ports, they change which runners in the intake are supplying air, long vs short.

The shorter the runners, the higher the HP peak.

The IMRC's open and add the secondary ports to the mix; they all have the same runner length, IIRC.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top