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Intake Question this time!

Good afternoon everyone, I have a intake question. I have a boss 302 intake that I purchased cheap, I talked to a tuner that I plan on taking my 12 GT to and he said I should get the 18+ intake for instead. (less torque loss) my HP goal for the car is to get as close to 450 RWHP as possible without doing major internal work at this time. my setup that I was going to build was Boss 302 intake, LTH long tubes in 1 3/4", Airaid cold air intake, boss timing chain tensioners, and boundary oil pump gear.

should I sell the boss 302 intake and buy a 18+ intake or no
Car mostly see street driving and Autocross duty
 

Mad Hatter

Gotta go Faster
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3,439
Santiago, Chile
I asked Shaun at AED about the same thing, He told me to go for Cobrajet, and was not at all positive about the 2018+ manifold in a gen1 engine. I got the impression he would not tune the engine with it (gen1).

When I asked Shaun if the Cobrajet was worth all the $$ for 15hp more... he said, well that's 15hp you didn't have before......
 
I asked Shaun at AED about the same thing, He told me to go for Cobrajet, and was not at all positive about the 2018+ manifold in a gen1 engine. I got the impression he would not tune the engine with it (gen1).

When I asked Shaun if the Cobrajet was worth all the $$ for 15hp more... he said, well that's 15hp you didn't have before......

So from what I was understanding the tuner was saying it was better for the first gens because it was able to achieve a higher gain at a lower RPM due to the first gen motors not being able to reach higher then 7200RPM safely, also they don't lose the low end torque from what he said.
 
This is a question I asked when I was upgrading my track-only 13 Boss. As Hatter said, the CJ was what both AED Shaun and my tuner recommended. From what the folks at Vorshlag noted, as you move up to Gen2 and Gen3 Coyotes the changes that were made suit the 2018+ intake more it appears and HP gains are much easier. The Gen3 motor makes almost the same HP as my Gen1 (cams, CJ intake, 100 octane tune and electric water pump) with nothing more than LTH, CAI and a 93 octane tune. See their comment below:
The key to reliability is to NOT REV THESE ENGINES above about 6800 rpm. I see so many track Coyote folks tune their engines (via intake and other mods) to make a tiny bit more peak power at higher RPMs, but if you let these engines touch 8000 rpms they are dead within a season, or less. DON'T use the Boss302 or Cobra Jet intake, they just kill avg power and push the peak power higher and higher. Notice how the 2018+ and GT350 engines went back to the long runner intake manifolds?
For a Gen1 coyote I am very pleased with my set up. I shift at 7300 even though it's still pulling so hopefully I get longevity.
 
This is a question I asked when I was upgrading my track-only 13 Boss. As Hatter said, the CJ was what both AED Shaun and my tuner recommended. From what the folks at Vorshlag noted, as you move up to Gen2 and Gen3 Coyotes the changes that were made suit the 2018+ intake more it appears and HP gains are much easier. The Gen3 motor makes almost the same HP as my Gen1 (cams, CJ intake, 100 octane tune and electric water pump) with nothing more than LTH, CAI and a 93 octane tune. See their comment below:

For a Gen1 coyote I am very pleased with my set up. I shift at 7300 even though it's still pulling so hopefully I get longevity.

So basically you guys are backing up what I was already thinking and that I would not benefit from a intake unless I get boss cylinder heads and take car of the bottom end issues that I informed about in my other post.
 

Mad Hatter

Gotta go Faster
4,691
3,439
Santiago, Chile
My understanding was just that the 2018+ manifold is a pain to tune in the gen1 and can result in power loss. All my friends with gen1 GTs at the track are running to 7500rpm in any case. But with fingers crossed!

Somewhere here some one posted about losing power after going to the 2018 manifold in a gen1
 

Mad Hatter

Gotta go Faster
4,691
3,439
Santiago, Chile
This is a question I asked when I was upgrading my track-only 13 Boss. As Hatter said, the CJ was what both AED Shaun and my tuner recommended. From what the folks at Vorshlag noted, as you move up to Gen2 and Gen3 Coyotes the changes that were made suit the 2018+ intake more it appears and HP gains are much easier. The Gen3 motor makes almost the same HP as my Gen1 (cams, CJ intake, 100 octane tune and electric water pump) with nothing more than LTH, CAI and a 93 octane tune. See their comment below:

For a Gen1 coyote I am very pleased with my set up. I shift at 7300 even though it's still pulling so hopefully I get longevity.


You said that much better then I did 👍 :)... But disagree with Fair in that the only way i could keep up to the faster cars in my class is to go the 7800rpm.. Maybe for Time trails, but for Wheel to Wheel that little bit extra makes for that last minute pass possible. that said, I am on my third engine.:eek:
 
Here's some further information that may assist in the decision.

Gen 1 "2011-2014" Intake Manifold
Runner length: 12.178 in
Total intake volume: 569.034 ci

Gen 3 "2018" Intake Manifold
Runner length: 16.141 in
Total intake volume: 665.158 ci

Illustration to show how the runner length is packaged into the intake and how the plenum sits in the valley:
1612995231285.png
FR3E: 2015-2017
JR3E: 2018+
GR3E: GT350

Boss 302 Intake
Runner volume: 29.690 ci
Runner length: 9.327 in
Tuned for 7,750 resonance peak

"The Cobra Jet used the same runner design as the Boss, with the exception being the reduced bump around the injector pocket," says David Born (Ford Performance Parts Engineer). "The Cobra Jet uses a different manufacturing process which allowed the bump to be reduced, which in turn reduces the flow losses around the bump and provides an increase in performance." The Cobra Jet is really just the Boss manifold with a dual-bore inlet added and the strut tower brace recess removed, with the aforementioned having a negligible impact on performance.

Intakes basically have a couple points in which they reach resonance peaks where they best perform. Ford has to tune each intake with their software to meet the demands of each particular engine. The Gen 1 Coyote falls off between 6500-6800, well, because that's where the redline is. The demands of a Roadrunner engine with a 7,500 rpm limit and a GT350 with a 8,200 RPM limit will have (sometimes vastly) different considerations in their design and runner length. You can see that here very clearly in a comparison between the 2018 intake manifold and the Cobra Jet:
1612995523690.png
The 2018 manifold is hitting peaks at 4,800 rpm, 5,700 rpm, and 7,000 rpm in this example.
The CJ manifold is hitting peaks at 5,400 rpm, 6,500 rpm, and 7,800 rpm in this example.

Now that you've seen a drastic comparison, here is a more subtle one, the difference between the GT350 Intake and the 2018 that was later derived from it:
1612996313325.png
You can see that the GT350 resonance peaks have been shifted to the right on the graph, to lend in the greater RPM limit of that engine (8,200 RPM limit versus 7,500 on 2018+). The Boss intake has a resonance peak at 7,750 rpm (very similar to the CJ, naturally, as they're cousins).

My newbie opinion is, unless you're doing supporting mods for RPM, I'd probably stick with the stock intake or the 2018 intake. The stock intake should be suitable for autocross, since traditionally cone courses see drastically varying RPM load and not usually staying at max RPM for long distances (at least not at my ability and at the tight courses I attended). The 2018 intake might be a decent choice if you wanted a less expensive road course modification, since it does 'free up' the top end when compared to the Gen 1 intake manifold and lend to an environment where you have a higher chance of running out each gear to the top (but keeping stock RPM limit and not being able to utilize the Boss or CJs resonance peaks out to 7,800 rpm). Let me know if I got anything wrong, but this represents my current understanding.
- Information snippets and graphics from Hot Rod

VMP did a few videos testing many of the intakes available for the Coyote. Here is their Gen 1 video that may also provide some useful insight:
 
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But disagree with Fair in that the only way i could keep up to the faster cars in my class is to go the 7800rpm.. Maybe for Time trails, but for Wheel to Wheel that little bit extra makes for that last minute pass possible. that said, I am on my third engine.
I agree with you Mad Hatter but you are pushing your car much harder by necessity. I asked my tuner (Rev Automotive) about bumping up the RPM limit and he told me I was already at a 7500 cut off (which I often hit) and that was his limit for motor protection. As you said, it will pull nicely to 7800 but I want to keep my motor as long as I can before needing a refresh/replacement. I don't see my self just doing a refresh and I'll likely want an Aluminator or something pricey but I can't swing that now so safe is better.

My newbie opinion is, unless you're doing supporting mods for RPM, I'd probably stick with the stock intake or the 2018 intake
If I wasn't doing the L&M cams and bigger TB I would have kept the Boss manifold but the CJ works really well with both of those mods on a Gen1 per AED and Rev Auto so I took their advice. That 15HP+ was worth it.
 

Mad Hatter

Gotta go Faster
4,691
3,439
Santiago, Chile
Beware,,,, the Cobrajet manifold is terribly finished with gaping huge ugly gaps in the plastic joins. Really a horrible piece of work. The box should come with a warning... PORTING AND POLISHING REQUIRED. Meanwhile the 2018+ mainfold comes out of the box looking like a decent production part. I am positive a ported Cobrajet will come out on top.
 
1,234
1,017
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
I have a ported 2018 IM on my 2014 GT along with L&M intake cams and Boss 302 exhaust cams. With the tuner (remote tune) I was using when I installed the parts, my HP kept going up until 7000 rpm (stock dropped like a cliff after 6400) and a only a slight decrease to 7500. However, I did lose a little bit of mid-range HP and a bigger loss of mid-range torque.

But I think this was because my tuner at that time was not experienced with the L&M cams. I took it to RevAuto for a dyno tune and Adam recovered my mid range torque & hp and even gave me a little bit more on the top end.

My car is dual purpose street and HPDE. Depending on how tight your autoX courses are you may even benefit from the increased torque of an F-150 Coyote manifold.

Even with a 2018 manifold I don't think you're going to get close to 450hp without upgrading your cams. MAYBE with E85.

And don't forget the billet crank gear.
 
194
312
Exp. Type
Time Attack
Exp. Level
5-10 Years
CA
My understanding was just that the 2018+ manifold is a pain to tune in the gen1 and can result in power loss. All my friends with gen1 GTs at the track are running to 7500rpm in any case. But with fingers crossed!

Somewhere here some one posted about losing power after going to the 2018 manifold in a gen1
Happened to me. I drank the coolaid and got the a ported 18 intake right away. The results where not what I expected and since I got a stock 11 Gen1 I was not willing to rev past 7k. So I went back to the stock 11 GT and enjoyed the beefy midrange.

Sadly I could not dyno the 11 GT manifold with the JLT2 intake and a tune the same day. But this is still better than nothing and gives you some idea how an 11 GT manifold compares to a ported 18 without and without tune:
1622913377933.png
I`m still curious what the go to solution is for a Gen1 if I would upgrade springs and cams and extend the rev range to ~7500. I got the ported 18 with lockout right here, but from the sounds of it a CJ would be better.
 

Mad Hatter

Gotta go Faster
4,691
3,439
Santiago, Chile
All the usual goodies like headers, TB and CAI etc would help, but for the manifold, being limited to 7000 rpm really cuts back on the gains from a CJ manifold. A track buddy had a S550 with the same rwhp as me. But at the track, on the straights, I would walk away from him when he got to 6500rpm while I was still making power past 7800. It turned out I was making more then 50rwhp then him at that point.
 

JDee

Ancient Racer
1,517
1,545
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
The Mustang shop I deal with is really down on the '18 swap, they won't touch them anymore as they were spending way more time trying to tune them than they were comfy with having to charge for. They also told me there were a lot of reliability problems with that setup on pre '18 cars. I didn't press them further on that, once they said "reliability problems" it was a non-starter for me.
 
194
312
Exp. Type
Time Attack
Exp. Level
5-10 Years
CA
oof, that is quite a clear answer. So what´s the way to go and what rev range is recommended? I assume the simple answer will be CJ and 8k, but I`m curious if you guys have a couple more tips or advices to share. Is there any gain in porting a CJ for road course use?

Headers, free flowing exhaust and a big CAI are in place. I´m generally trying to stay on the safe side where possible to keep wear and heat generation at bay. But I also understand there is only so much that can be done if power wants to be made.
 

Mad Hatter

Gotta go Faster
4,691
3,439
Santiago, Chile
oof, that is quite a clear answer. So what´s the way to go and what rev range is recommended? I assume the simple answer will be CJ and 8k, but I`m curious if you guys have a couple more tips or advices to share. Is there any gain in porting a CJ for road course use?

Headers, free flowing exhaust and a big CAI are in place. I´m generally trying to stay on the safe side where possible to keep wear and heat generation at bay. But I also understand there is only so much that can be done if power wants to be made.
Which tune do you have? I am a bit engine senstive lately as blown engines tend to make for nightmares and lost hair. But being able to go to 7800 really helps at the track and that's were the CJ shines (the boss manifold is not terrible either).

My old Boss manifold went to a friends car and his lap times dropped right away. So they cant be all that bad.

About the CJ manifold... Love it BUT.. I think they should come with a warning that says PORTING WILL BE REQUIRED..... The CJ is really hideous inside with huge gaps and bits of plastic hanging around, ports are bad as well... I think thats why the 2018 gave better dyno numbers in the press. The 2018 units is a production part, while the CJ is definitely not, and it really shows in back to back visual comparison. Needs love and care to get it looking half decent. Am pretty confident that a Ported CJ is better then a 2018 manifold. AND.. it works well with the gen1 and 2.
 
194
312
Exp. Type
Time Attack
Exp. Level
5-10 Years
CA
Which tune do you have? I am a bit engine senstive lately as blown engines tend to make for nightmares and lost hair. But being able to go to 7800 really helps at the track and that's were the CJ shines (the boss manifold is not terrible either).

My old Boss manifold went to a friends car and his lap times dropped right away. So they cant be all that bad.

About the CJ manifold... Love it BUT.. I think they should come with a warning that says PORTING WILL BE REQUIRED..... The CJ is really hideous inside with huge gaps and bits of plastic hanging around, ports are bad as well... I think thats why the 2018 gave better dyno numbers in the press. The 2018 units is a production part, while the CJ is definitely not, and it really shows in back to back visual comparison. Needs love and care to get it looking half decent. Am pretty confident that a Ported CJ is better then a 2018 manifold. AND.. it works well with the gen1 and 2.
Custom dyno tune from a local reputable tuner shop. They had hard time with the 18 though.
My current goal is a redline around ~7500 with a safety zone till 8000. I noticed that even though my rev limiter is at 7000 the revs spike up to 7200. Better save then sorry.

Do you have a dyno sheet or power band curve you`d feel comfortable sharing? Anything that helps to visualize what you are working with.
 

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