Cobra Jet manifold reworking

86merc

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We did get some testing in. The throttle body numbers were odd. Each throttle body had significant swings in peak numbers.We had some issues with the SCT Live Link. So maybe the delays caused warmer temps resulting in reduced numbers. So we will be revisiting the throttle body test for sure.

The cleaned up intake was well worth the effort. We saw nice gains across the whole power band.

We will have some info and dyno graphs soon. Hopefully later today or tomorrow. And yes. We will be back on the dyno again. Just trying to see what works for our schedules.
 

86merc

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Great test! That blue filter is pretty small though for the cfm requirements you'll be needing.

Not many filters out there for a 4.5" tube. This one has a smooth radius inlet unlike many other ones out there. Of course we could not find any information on the flow numbers on this one. But it was one we could get in short notice. We are looking into a longer body filter. That will be another change next time out as well.

M5lp 1207 015 Coyote 5 0 Engine Photo 15


the originals did not have the removed step of material at the bung that the new cj manifold has. the big difference between this and boss is the bung area thickness and tb size. not sure when the entire bottom segment of material was removed but that is obviously making some power.

PS most of the manifold weld line mis-match is in the outboard runner - there is almost no laminar flow in that area think of the engine sucking in air and it follows the inboard edge of the runners... that's why ford left that flange in on the stock and boss intakes, and now it seems on the cj intakes.

I agree. I think the reworked injector boss and throttle body inlet were the big contributors to the increased power. The throttle body inlet had a lot of mis matched castings causing a large lip in several spots. Besides the injector bosses, Drew just blended what was there. I would not call what he did in the ports as "porting". Blending and cleaning is more accurate.
 

Blazer707@TBR

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Not many filters out there for a 4.5" tube. This one has a smooth radius inlet unlike many other ones out there. Of course we could not find any information on the flow numbers on this one. But it was one we could get in short notice. We are looking into a longer body filter. That will be another change next time out as well.



I agree. I think the reworked injector boss and throttle body inlet were the big contributors to the increased power. The throttle body inlet had a lot of mis matched castings causing a large lip in several spots. Besides the injector bosses, Drew just blended what was there. I would not call what he did in the ports as "porting". Blending and cleaning is more accurate.

Ill be doing the same thing on the injector bosses, tb opening and smoothing out all gaps also on mine. Looking forward to seeing the graphs.
 

86merc

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This is Drew's reworking of the CJ intake thread. We can make another thread with the other info and testing. So for now I will just post up the as delivered CJ intake versus the one Drew cleaned up.


Both intakes were run with the SCJ mono blade throttle body. Both were ran with the exact same tune. Only the intake was changed.

SAE

graphportcjsae_zpsa56c9a95.jpg



STD

graphportcjstd_zps99bfa3f5.jpg







With the cleaned up intake there is a solid 10-12 HP & TQ increase through out most of the RPM. :rockon: Nice work Drew!
 
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Defiant 5.0

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Those are some very promising numbers. I wish I could afford a CJ intake, but then I'd have to clean it up lol. I'm just not willing to push my engine to 7800. I think I'm going to have to get a Boss mani instead.
 

Shaun@AED

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Amazing what attention to detail and minor modifications can do!

Same goes for exhaust and really any other mod you do. Making minor changes here and there all add up.

Good Job guys!
 

blackcoyote13

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This is with cat delete pipes, so figure around 400ish at the wheels with stock cats and a not "cleaned up" CJ manifold and SCJ mono-blade?
 

SmokeGreyHatch

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This is Drew's reworking of the CJ intake thread. We can make another thread with the other info and testing. So for now I will just post up the as delivered CJ intake versus the one Drew cleaned up.


Both intakes were run with the SCJ mono blade throttle body. Both were ran with the exact same tune. Only the intake was changed.

SAE

graphportcjsae_zpsa56c9a95.jpg



STD

graphportcjstd_zps99bfa3f5.jpg







With the cleaned up intake there is a solid 10-12 HP & TQ increase through out most of the RPM. :rockon: Nice work Drew!

Nice numbers. Was this on 93 octane? Also full exhaust and what gears/tire height? Do you have a full mod list? My car made 453 with the JLT bottleneck and another 10 with the Kenne Bell 4.5'' test pipe we had all on 91 octane. Curious on the comparison. sounds like your TB testing meshes with my previous calculations? Were the dual bores pretty bad?
 

01bluesnake

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This is Drew's reworking of the CJ intake thread. We can make another thread with the other info and testing. So for now I will just post up the as delivered CJ intake versus the one Drew cleaned up.


Both intakes were run with the SCJ mono blade throttle body. Both were ran with the exact same tune. Only the intake was changed.

With the cleaned up intake there is a solid 10-12 HP & TQ increase through out most of the RPM. :rockon: Nice work Drew!

Thanks again Mike! as always was a good time on the dyno with testing. I'm still so happy with how well the intake responded to the minor tweaks. The throttle body test were so inconsistent between the two that i really can't make a conclusion either if the CJ is better than the twin blade. Will need to get out again for sure, Maybe E85 tune this time out? lol

Those are some very promising numbers. I wish I could afford a CJ intake, but then I'd have to clean it up lol. I'm just not willing to push my engine to 7800. I think I'm going to have to get a Boss mani instead.

They are very good numbers, was expecting that and was not disappointed by the CJ mani. Coupled with the port work the gains were well worth the change up. Even with the Boss, you will be revving to 75-7600 to make the best out of it. I'll have to do an overlay with the Boss from my previous dyno test and the CJ and see how they overlap. I have a feeling the cleaned up CJ is a better contender even at Boss RPM range.

Good solid gain on the smoothed out one!

Thanks, was definitely the best part of my day. I was stressing over it, was hoping i didnt just kill a CJ mani lol.

Amazing what attention to detail and minor modifications can do!

Same goes for exhaust and really any other mod you do. Making minor changes here and there all add up.

Good Job guys!

Thanks Shaun, Your tune is amazing as well!! I will be contacting you soon to go over to the AED side, just waiting on injectors to get the car back on E85.
 
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86merc

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Amazing what attention to detail and minor modifications can do!

Same goes for exhaust and really any other mod you do. Making minor changes here and there all add up.

Good Job guys!

Once the updated tune is done we will be back on the dyno for new tests. The parts are looking good. And I know the tune will rock.

This is with cat delete pipes, so figure around 400ish at the wheels with stock cats and a not "cleaned up" CJ manifold and SCJ mono-blade?


Once my CJ tune is dialed in we will be back on the dyno for stock intake versus CJ intake runs. I went 11.44 with the stock intake so far. I am interested to see what the power differences are from the stock intake to the CJ/mono blade set up. Then will back at the track for more testing there.

Nice numbers. Was this on 93 octane? Also full exhaust and what gears/tire height? Do you have a full mod list? My car made 453 with the JLT bottleneck and another 10 with the Kenne Bell 4.5'' test pipe we had all on 91 octane. Curious on the comparison. sounds like your TB testing meshes with my previous calculations? Were the dual bores pretty bad?

This was on 93 octane.

The exhaust is stock headers, Jeg's cat deletes, Borla X pipe, Borla over the axle pipes and JBA axle back.

Different dynos so hard to compare. But I am sure Shaun could clue you in to what timing you run versus what mine will run once the final tune is done.

The throttle body test was all over the place. Very inconsistent numbers. We will be re running that test again.

We will be trying a larger air filter as well. A larger one may pick up. We will see what happens. We will try to get the parts in and get back on the dyno as soon as possible.
 
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90goldtsiawd

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Doesn't anyone think it's complete BS that you have to do that work to the CJ manifold for how expensive it is?
 

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