Where to place mod motor restictor plate?

[GT4Point6]

Where would a restrictor plate be placed on a mod GT motor if your over the HP/TQ limits? I have a hard time imagining a plate behind the TB without the TB (just under 80mm stock) hitting it during WOT if it is smaller than the TB. There is no spacer between the tb and the aluminum elbow. Could the plate go between the aluminum elbow that flows into the plastic intake and the manifold itself? Just trying to picture it in my head and haven't seen a mod motor with a restrictor plate. I can post a pic if you would like, not sure where it would go.

 

Looking at running in the 05 season (if all goes well with at sea times and up coming deployment). Currently, the car made 240/275 corrected (dynojet 248a) through the cats with legal mods. Will run again without cats next month for a better idea of of how it would be ran at the track.

 

Thanks,

01 Mustang GT

[John Barker]

Kevin ,

I am new to cmc but if i am reading the rules right it says the restrictor plates are for the newer GM cars with the 5.7 motors. Mabe someone else can clairfy the rule ? Just trying to help you out.

________________________

John B CMC # 49 TA

[Tony G]

True,

But if your over on power, you can add the weight over 3200lbs ( see chart in rules) or put in a restrictor, or better yet close off some of your air filter area.

We can work on this.

Thanks,

Tony

[GT4Point6]

John

 

I just noticed that the restrictor plate is directed at the 5.7. Thanks for pointing that out.

 

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Tony G

 

I'll look at fabricating up some sort of restrictor plate or closing off some of the filter. I'm running the stock airbox and silencer right now. I'll play around with it some more on the dyno to see what works after I put the off road x pipe on and see where it stands.

 

Thanks all,

[trackboss]

I second what Tony suggests. Close off the area that the filter draws air from. Altering the area aft the mass air meter may possibly affect the air/fuel mixture more so than the former because the motor thinks it is getting a certain amount of air and may not. Plus it is just easier the other way.

 

This may be slightly out of context here, but looking at your numbers I think the mod motor may be at a disadvantage because of torque compared to the pushrod motors in CMC format. It might be worth it to have an experienced tuner try and burn a custom chip on the dyno to help that situation and consider it for next years rules.

[GT4Point6]

Tony G and Trackboss,

Thanks for the recommendations, will try the inlet area first to keep the A/F ratio straight. Will dyno next month with o/f X and see where it stands from there.

[GT4Point6]

Trackboss

Are they going to allow chips next year? The dynoshop mentioned they could tune it so the have that capability.

 

Just dyno'd the car with the off-road x and picked up 15hp and 15tq at the wheels. Now I'm over by 25 HP (255) and my tq is good at 290.

[Tony G]

You are now at what a stock 93-97 LT1 Camaro comes with.

We restrict them with the restrictor plates installed and get them down to the 230 HP with no problem.

So I would say you are going to have to install a plate and will have to play with it to see what works,since you are the first Mustang to have to go DOWN on power.

No chips allowed in the rules.

Tony

[GT4Point6]

Tony G

 

What size restictor plate is used the most and what size MAF and TB does the LT1 use? Just trying to get a feel for what size I should start with. I'll try Trackboss' suggestion of chocking it off at the silencer first, then maybe try the TB restrictor. Either way, less air should produce less power.

If only I could cut the power and keep the torgue.............

[Al F.]

This is actually very interesting... In any case, the LT-1 has 52mm bores in the throttle body. Mine is running a restrictor with 33mm holes and 232 ave hp.

[Tony G]

Seems like every LT1 is running the 33MM.

Let us know what works on the Mustang as you are the first to try it.

Good Luck!

Tony

[Al F.]

Of course we are...because all of our motors are stock.

[Tony G]

Al,

Your motor is stock because remember I built it...ok almost stock..

Wish I had 232 HP!

Tony

[Al F.]

Why, so you can race the AIX cars? Hey, thats IT! Instead of award weights, we'll have award restrictor plates! Win and you gotta run a 25mm plate for three races. That'll slow you down!