Think this intake swap will hurt performance?

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UOP

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I've taken the first step in my turbo swap and sourced a Mopar M1 single plane intake (what a pita to find for a magnum btw), and will be installing it this week. To be honest I'm not too worried about losing a little hp/tq since I bracket race mostly, but I am curious what you guys think. Current setup is running an Edelbrock Air-Gap w/ 1/2" open spacer, 9:1 360 magnum, 216/224 .506/.506 114, 850 dp, and I shift at ~5500. A run from last friday:

R/T: .015
60: 1.624
330: 4.805
660: 7.519
MPH: 90.21
1000: 9.871
1/4: 11.860
MPH: 112.46

Care to make any predictions? Do you think my carb settings will change much?
 
Unless it's boosted, IMO, you're replacing a good intake with a pile o'crap... Don't like the M1 at all.

Let the hating begin. :)
 
Nice job on getting into the 11's... :)

I know you've been working hard to get there.
 
Since at this point you own it..bolt it on and see how it runs...you can always go back to the air gap...only cost intake gasket and time.
 
70aarcuda said:
Since at this point you own it..bolt it on and see how it runs...you can always go back to the air gap...only cost intake gasket and time.
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x 2, might as well try it...but it will probably slow you down....and for $16.95 and couple hours of your time, you can change it back. :D
 
This is what I would do: Figure out your goal, then talk to a knowledgeable custom cam grinder and tell him your goals and combination and have him grind a cam for your combination. He can grind a cam to make your combination come alive. He can also give you hints on tweaks you can do to really maximize your combination. (Don't be surprised if he hints at a 4000-4500 stall converter)

Unless your car weighs a ton, my slide rule says you are making around 300 RWHP and around 330 RWT. With the right cam I think you can get closer to 360 RWHP and 360 RWT.

That should put you close to low 11s at 118-120MPH.

So what is your goal?
 
OK, I'll take the other side of the coin. I think you'll e.t. the same a get a bit more mph.
 
Are those cam specs for 1.5 rockers, 1.6 rockers, or part of both (lift at 1.6 but duration @ .050 with 1.5s)?
I agree with IQ basing it on that last possibility. I think you might lose a little off the 60' but overall the the mph will go up. I'd like to see another 5-8° @ .050 duration in it tho.
 
Unfortunately I won't be able to swap back if I don't like it. I arranged a swap with another member so as soon as the airgap is off it's going to a new home.

As for the cam specs, that's what Comp spec'd out for a turbo cam. I've just been running it n/a all this time. The lift ratio is for stock 1.6 rockers.

I agree with more converter. I've been thinking about sending it to be restalled. My car will 60 ft in the high 1.50's but I really have to push hard and risk pushing through the brakes.

The current goal for the car is to be able run 7.0/11.0 index with the ability to run well in the 10's if I feel the need. Just a simple low boost/low rpm combo. I know a 100 shot would probably do the trick but I don't want to mess with filling bottles, watching temp and pressure, etc. Besides, boost has been the plan since day one.
 
UOP said:
The current goal for the car is to be able run 7.0/11.0 index with the ability to run well in the 10's if I feel the need. Just a simple low boost/low rpm combo.
Click to expand...


All I can say is stick with your original goal. You always end up wet trying to change horses in the middle of the stream. If the M1 intake is part of the current goal, then the affect on performance is irrelevant. If you are bracket racing then as long as your car performs well enough to stay in the desired bracket, then so what if it is slightly slower or faster?

I would not change the stall until you get the turbo installed and see where you are. Are you worried at all the IRS is going to hold up to 10 second abuse?

On pushing the car through the lights, have you thought about a 2 step (assuming it is legal for your class)? Another option is to get a window switch and 2 low rpm adjustable chips. Find out what is the highest, safe RPM you can use without pushing through the lights. Set one adjustable chip 100 RPM below the target RPM and set the second chip at the target RPM. put the chips in the window switch and hook it up to an LED you can see easily from the drivers seat. On the starting line, once you are staged, keep the LED lit and you should be good to go.
 
I'm just a bit too fast for the class I run and have to slow it down to keep from breaking out of the 7.65/12.00 cutoff. So maybe there is a benefit to it. I broke out yesterday with an 11.96 in the 2nd round as a matter of fact (trying to make up for a bad. 051 light).

The irs (should) be just fine. I don't think my car's 60 ft times are violent enough to be a problem. There are a few other guys with the same setup hitting it much harder than me. If you watch video of my car launching it really looks tame. The trans is also built to run in a turbo application.

I thought about trying some sort of two-step but they are not allowed in any of the classes I run.
 
You are PERFECT for running a 12.0 class, just add a little weight and figure out how much you can shave by dumping at the first mph marker before the stripe (usually a few hundredths). This would be a GREAT setup IMO, you would always have the advantage of being the faster car.
 
Because of the converter in the car, that's why I say you will go backwards. We've talked about his converter a few times. I'd expect it to lose ~ 20#/Ft of torque and it may match the upper rpm HP with an M1.
 
Do you use a shift light? I would try lowering your shift points to slow the car down. You can add weight by running with the gas tank full or adding weight in a safe location.

You can hit a test and tune where you have an opportunity to get a few passes in. You need 2 baseline passes then try shifting 200 RPM sooner via the shift light for a pass. Next try shifting 400 RPM sooner.

You will also want to repeat the testing by adding know weight amounts to the car.

Between these two variables you should be able to adjust your ET to the index in varying weather.
 
Well I painted the M1 tonight so I'll install it tomorrow. I should be able to come back with results after tnt on Friday. I need to get it ready to run because I'm running at Mopars at the Motorplex on Saturday and another series I run on Sunday. I can handle it slowing down, a little, I just hope I don't lose the consistency.


Do you think I outta reuse the 1/2" open spacer?
 
If you slow it by adding weight (safely and correctly) it will be just as consistent - but slower.
 
Well I got the intakes swapped tonight. I still have a few things that need to be done before I get to test it out, but that should be finished tomorrow.
 
I think once you're boosting, the M1 will help. I Have a mate with a 318 running an M1 with eddies and a turbo. He's gone 12.7@8psi boost with 2.92 diff gears, and a very tame converter. With smaller gears, and more stall it'd go plenty faster I would say.
 
Well I made it to the track today and made several runs. As expected there was a loss of torque, but not too bad I guess. My best run of the day:

R/T: .018
60': 1.672
330': 4.922
1/8: 7.668
MPH: 89.17
1000': 10.051
1/4: 12.055
MPH: 112.54

I'm doing this from my phone, otherwise I would put the before/after stats side-by-side, but basically 2 tenths slower at the same mph.
 
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