10 HP/TQ. Nice. I am convinced. I always thought the stock box was adequate. Obviously not. Really nice change in IAT and the associated timing advance. I guess I'm going to do the windstar cowl intake.
Dyno Testing Bolt-ons On The 4.0
- Thread starter Jezza
- Start date
10 HP/TQ. Nice. I am convinced. I always thought the stock box was adequate. Obviously not. Really nice change in IAT and the associated timing advance. I guess I'm going to do the windstar cowl intake.
Those were some WAG numbers based on a super oversimplified volumetric flow theory.
Realistically the backpressures are way lower than that and it's hard to characterize it in terms of just volumetric flow because gas is compressible and also cools as it is expanded.
Modern Ecoboost engines will run up to 20 PSI on 87 octane as one example. What the backpressure PSI is on that I have no idea, but as a WAG I would guess up to 5 PSI.
I mean it's 8% that's a decent gain. Maybe not the 20-30 that the filter guys advertise but I don't think anyone expects to make those numbers. I do have a spare 00+ manifold, but it doesn't have the power steering bracket on it. Maybe I can tig one back on at some point.
This is making me wonder , how much of the gain is due to restiction , and how much to cowl air temp ? If you know someone with the typical " CAI " you could borrow for a hour it would be an interesting test . Any gains over stock ?
I'm not trying to dream up more effort on your part , your dyno run tests are the best real life tests I've ever seen ! Thank You !!!!!
Good stuff! What I noted is that static IAT was lower at idle in edition to the lower WOT and then corresponding 2 degree timing advance from the ecm. Nice to see the gains showing across the rpm not just at peak.
DirtDawg
TJ Enthusiast
An interesting mod (which I'd seen online recently) as well as net gains, however my question is; how frequently does a TJ/XJ 4L need to be run at WOT? My experiences with my former 2000 TJ (owned from factory ordered new for 21 yrs), prompted me to keep the OEM airbox while applying a thin smear of grease around the filter panel periphery to seal that off from any potential dust leakage. I preferred OEM style vs K&N (or equivalent) drop-in filter panels to ensure the reasonably cleanest possible air inducted in real-world off-pavement trail usage. My recently purchased 2005 TJ Rubicon (see avatar) came with the common K&N aftermarket cold air intake, which I'd replace with the OEM in a heartbeat if that had been retained by the former owner...
Got proven wrong here, in that it did show up on the inertial dyno.
I wouldn't be surprised to see an even bigger gain in real-life highway conditions as the computer pulls less timing on long high-power runs. The biggest thing I noticed with the Windstar intake is that there was less of a "bogging down" effect while climbing long hills caused by staying at full throttle for some time.
There is also possibly a very slight ram air effect due to the position of the cowl intake. If you pull the fuse on the HVAC fan and leave the system on outside intake, the recirculation door doesn't close, and you get a bit of a ram air effect at highway speeds pushing air through the vents, even though the fan isn't spinning. Presumably this would impact the intake as well.
However I suspect those ram air effect gains are marginal at best. At 70 mph, you would theoretically see a maximum of a 0.60 kPa gain, which would give just under a single horsepower. The timing gains are probably significantly more important.
Agreed with above. Would love to see the new intake just rotated a little and not poking through the firewall so it can suck in nice warm under hood air to see what happens. Regardless of restriction vs temps or a combination of the two, I think this definitely answers the question in all but the most stubborn of minds reference the Windstar intake mod. Thank you again for your efforts Jezza!
Did you watch the video? The gains were at 3K RPM's also... 10HP & TQ while not a lot is an improvement.
And as shown doing the Windstar intake gives you a "real" CAI type system that also offers an improvement over the stock air box. I'd replace your current CAI with a Windstar intake and see what you think... Other than the hole in your firewall if you don't like it you could remove it. And you can plug the hole...
I think driving style is probably relevant to the how often a person WOT, I am almost daily. I have to pull out of a working parking lot onto a not so rural highway so 0-60 romps is almost a daily occurrence.
I went this direction with a XJ filter as I was not so eager to drill a hole, keep my paper filter in the Jeep family, Hastings list the XJ panel filter as marginally higher CFM too. This pic is a little dated as I have got some tin work that is tighter to the front bulk head to grab air from around the head light and hood gap.
After watching your Windstar video, I immediately began researching making and installing one of my own. Your set up is by far the cleanest I’ve seen. I like the larger 3” diameter and the excellent mounting, especially the aluminum horn at the firewall. Are you considering manufacturing some or all of these parts and selling them individually or as a kit? If not, I wish you would and I’ll be your first customer.
DirtDawg
TJ Enthusiast
Yep, did fully watch but then again just now with that noted gain at ~2900 rpms shown prox 13 mins in. Also watched the video from same channel 3 yrs ago (green TJ - perhaps same jeep before painted red?), wherein comparos between OEM and same K&N CAI on mine netted ~ +8 hp / + 5 tq (rounding), although those max numbers don't correlate with today's test numbers nor were ambient and IATs likely similar from that much earlier testing. Despite all that, I'll be shopping a used OEM box while appreciating the ingenuity and shared information!
I found myself romping the throttle for a week after installing the windstar on my stroker. Definitely a noticeable improvement.
A cowl vs engine bay draw test would be interesting!
Thanks @Jezza for the real data,both power and idle/wot air temps!
This. Put me on the list too if these parts become available.
@Jezza maybe I can borrow your hole saw
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I did another video a few years back with a older Banks cold air. I did that one vs the stock box but with the hood open. The gains were similar 8-9 hp iirc.
If you're making a kit and clearly you have a plastic printer...why not print the entire Windstar intake piece with all the necessary shorting modifications?
Probably could 3d print the piece that goes into the cowl too.
-Mac
Probably could 3d print the piece that goes into the cowl too.
-Mac
I am not planning on selling any Windstar parts. There is nothing there that can't be reproduced by the average garage mechanic, or sourced easily online. The only "special" parts I made were the air horn going through the cowl, the delrin fitting and the bracket to hold it up. You can find the 3" aluminum reducers on ebay. Same with a threaded fitting with a hose barb. The only part you would need to make is the bracket, which is really optional. The piping and cowl hole hold the box pretty good.
It's probably going to melt. I have an aluminum pass thru I made as well that will probably get used long term. I had it on there , but it was making a squeaking noise when the engine moved. I will probably isolate the inside with a strip of door edge trim or something.
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