how to clean or delete my imrc's on 98 cobra
- Thread starter kirkster
- Start date
Soaking the plates in degreaser or Seafoam is a good way to clean them. The carbon will rub right off.
You can delete them by removing the butterfly plates and the main shaft. Fill the holes with Quicksteel or JB Weld and you're done. I can send you pics of my before and after if you want.
You can delete them by removing the butterfly plates and the main shaft. Fill the holes with Quicksteel or JB Weld and you're done. I can send you pics of my before and after if you want.
You can delete them with the MMR deletes below, we have seen to many engines fail from epoxy or failed deletes falling into the engine (this is good for us because we get to sell engines but we would prefer not to sell them this way LOL) If you would like to keep them functioning a good cleaning agent will do it! Good luck!
They are $279 (but we have them on ebay for $249 shhhhhhh)
They are $279 (but we have them on ebay for $249 shhhhhhh)
I deleted them because the control box stopped working and they were stuck closed. The car feels a slight bit "sluggish" in the low rpms but once you get into the powerband you can definitely feel a difference. I still need to get a tune but some other members have said the deletes net about 8-10hp up top with a proper tune.
PM me your email and I'll send the pics when I get home.
PM me your email and I'll send the pics when I get home.
This is a great observation and what most of our customer say also !:beer:
Pretty much the only way you are going to gain any power with IMRC deletes is if yours were stuck closed beforehand.
What he said... Clean them up and leave them. If they are working right they will do a good job keeping power down low and up top to. If you delete them you should be running a ton of HP or have some 4.56s in the back.
Well, this part is not true, at least not for a forced induction application or a modified n/a application. Removing the shaft and the valves increases flow by more than 7 cfm in both runners (when tested on a flow bench at 28"), this translates into a minimum of 6+ hp even in a n/a application. :beer:
MMR
If you need a how to, I have a pretty good one that I, along with others, wrote for the Mustang Cobra Club several years ago.
Just PM me your email and I'll send it when I get home from work.
Just PM me your email and I'll send it when I get home from work.
Well, this part is not true, at least not for a forced induction application or a modified n/a application. Removing the shaft and the valves increases flow by more than 7 cfm in both runners (when tested on a flow bench at 28"), this translates into a minimum of 6+ hp even in a n/a application. :beer:
MMR
I would LOVE to see dyno proven power at the rear wheels going from working IMRC's to deleted IMRC's with nothing else changing.
There are plenty out there on the internet but to find one with nothing else changed may be difficult.
What you need to remember is that Ford added the IMRC to increase low RPM air velocity within the port, A forced induction application creates artificial velocity within the port rendering the IMRC not only useless but a restriction, Keyword being restriction, this restriction reduces HP (again in a forced induction application) and we have yet to see any forced induction application make less than 3-4HP MORE below 3000RPM, gains above this all the way to the limiter are in the 10+ range depending on the boost level. Ford Clearly recognized this and removed them after 98' (with some changes in the head of course to compensate)
MMR
What you need to remember is that Ford added the IMRC to increase low RPM air velocity within the port, A forced induction application creates artificial velocity within the port rendering the IMRC not only useless but a restriction, Keyword being restriction, this restriction reduces HP (again in a forced induction application) and we have yet to see any forced induction application make less than 3-4HP MORE below 3000RPM, gains above this all the way to the limiter are in the 10+ range depending on the boost level. Ford Clearly recognized this and removed them after 98' (with some changes in the head of course to compensate)
MMR
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Not arguing the fact of FI increased power. I would like to see NA increased rwhp from a clean working setup to deletes.
While we agree that is is minimal below 3k, gains are still seen on most modified n/a applications due to the lack of restriction. We would consider modified a vehicle with full exhaust, throttle body, cams etc. but again, i think you will have a hard time finding a dyno sheet comparing apples to apples as most people change other things when they tear into them.
is he not saying that simply take a car that has them installed and working and do a dyno, then tie the butterflies open and do another pull, and then on the same car, same application simply remove the IMRC's and do another pull so that there is no doubt about what works and not work?
Basically yes. Tying them open is not needed though. Just a pull with them clean and working perfectly, then same car put deletes on and change nothing else and make another pull. That would solve this debate.
I agree!
i cleaned up my intake manifold today. found out my IMRC cables were cut.
all i did was remove the butterfly plates and cleaned the rest up with a wire wheel. it was amazing how much carbon buildup i removed.
all i did was remove the butterfly plates and cleaned the rest up with a wire wheel. it was amazing how much carbon buildup i removed.
You can just remove the plates and leave the shaft that won't hurt anything ? Just wondering cause my cobra keeps throwing a code for the intake runner bank one .... not sure if that's what's throwing the code or not the car only has 30k on it
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