When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I seem to have managed to fabricate an alternative to the RR upper intake. 😁
I still need to do some dyno testing with the full 3.5 system but just the upper intake section made 12hp and 10tq at 6100rpm and picked up roughly 20hp/18tq in the mid range.
Unlike the RR which, from what Ive seen, tends to make gains in the mid range only and they diminish near peak rpm. The tubular upper intake makes more power and torque from start to finish.
Power below the curve is great and all, but power across the entire RPM range from the time you mash the throttle to the time you shift is better. 😈
Originally, I had planned on the RR upper and one of the J-Pipe intakes on the market until I started tearing the intake tract apart and realized how restrictive the stock intake is.
The RR has a larger diameter but it also shares the same design as the oem intake.
It has the same bottlenecks and inefficiencies...
I decided I wanted more volume and smoother more even flow than what the D shaped cast intake provides, so... I made my own.
It started out as a D shaped 4 plenum, which looked decent enough, but hood clearance was trash and in order to make it fit, it had to share some similarities to the RR/OEM design. It also had a very sharp transition from the round 3 J-Pipe to the plenum and the inefficiency was felt as a flat spot near the upper rpms.
I did some working around and decided a tubular, smaller diameter tube would be more suitable design for both efficiency and clearance.
The result was the first real prototype. The tubular 3.5 upper paired with the 3 J-Pipe both fit and performed well and is the design that was used for the dyno sessions.
Unfortunately, I wasnt able to source an RR intake or the oem plastic in time for my appointment due to tight restrictions and guidelines because of covid, so the testing for that particular session was just to see if my upper intake did better than the oem cast upper intake. Which it did!
In the dyno testing, we did pulls with both the stock cast upper intake as well as my tubular upper intake, both paired with the 3 J-Pipe.
The stock oem cast upper and 3 J-Pipe made 336whp and 358wtq.
The Tubular upper plenum and 3 J-Pipe made 348whp and 368wtq.
Finally going to the last version, I wanted to make sure I had everything I wanted in an intake, including headroom to benefit from once I go with a larger pulley later down the road. I pulled it all apart, redesigned most of it, and improved upon what I already had. The end result is a full 3.5 from TB to Airbox and not only does it look good, but it sounds amazing and performs well too. I even replaced the stock junk plastic breather tube with a more flexible, better quality solution!
Not too shabby eh? 😈
As soon as I get it back on the dyno with the new results for the full 3.5 system, Ill post back here!
Last edited by Joel Brown; Jan 10, 2021 at 02:39 PM.
great work! it looks amazing and the dyno shows it works. I assume it's cheaper then the RR intake listed on e bay from time to time. I'll follow this post...best of luck and i'm sure you have given me a warmer weather project too.
great work! it looks amazing and the dyno shows it works. I assume it's cheaper then the RR intake listed on e bay from time to time. I'll follow this post...best of luck and i'm sure you have given me a warmer weather project too.
Luckily, I have a wholesaler and supplier for aluminum piping and silicone just ten minutes from my house so I do get the parts cheaper than you can find on ebay, etc... makes things more affordable for sure!
Ive had a few Jag owners contact me to make them one so Ive sent a few out already. ☺️
I like your idea. So I copied it...sorry. Question. Did you have to oval the pipe at the 90 elbow to fit under the cowl? I did a test fit today. The runner that goes to the bypass valve contacts the pipe. So I'm thinking either the pipe has to be modified or the cowl? Your thoughts.
I like your idea. So I copied it...sorry. Question. Did you have to oval the pipe at the 90 elbow to fit under the cowl? I did a test fit today. The runner that goes to the bypass valve contacts the pipe. So I'm thinking either the pipe has to be modified or the cowl? Your thoughts.
I see eBay is flooded with the 3” intake pipes. But none of the rest of this assembly. Has anyone completed a copy of Joel Brown’s design? Looks simple enough. But definitely tight in there.
I want to keep the intake box.
I see eBay is flooded with the 3 intake pipes. But none of the rest of this assembly. Has anyone completed a copy of Joel Browns design? Looks simple enough. But definitely tight in there.
I want to keep the intake box.
i bought everything im going to copy and install it this week
Xalty,
Any chance we can get some detail on your materials? I may try this for fun, but need some more details on what to purchase. Thanks! Also, i like the black color much better then the red as it blends in with the engine compartment.
Xalty,
Any chance we can get some detail on your materials? I may try this for fun, but need some more details on what to purchase. Thanks! Also, i like the black color much better then the red as it blends in with the engine compartment.
Xalty,
Any chance we can get some detail on your materials? I may try this for fun, but need some more details on what to purchase. Thanks! Also, i like the black color much better then the red as it blends in with the engine compartment.