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Possible gains to be had, just need clearances from IM to Hood
Hi all fifth gens, im new to the fourm and i have a topic in eager to discus with another brand of car enthusiests. Im fresh of the acurazine fourm and they have tons of tech info on there. Anyway i was wondering what the stock hood to intake manifold clearance is on the 2000 se. Im interested in the topend you get from modding out plastic manifokds but would hate to lose some torque. I had a similar situation with my Acura CL, i loved the way my cai sounded but it didnt have the powee of the line it should have. So come to find out the Honda pilots use the same motor (in design anyway) as the acura, which means i can use parts of it. The pilot came stock with a almost 1.3 inch IM spacer to lenthen the runners , reduce heat soak, and ultimately shift the powerband lower and more useable torque on a daily is a good thing. I installed one on my acura with a thick thermal gasket and tge total height came to 1.5 inches of height. i had to cut some hood supports but not that many. Not only did i have my Tq back, it screamed at high rpms. After several WOT runs my manifold was COOL to the touch. Members have Dynoed up to 10tq and 10hp gains in the lower rpms with this part alone. My idea is to try this on the maxima i have to see if i can get similar gains. I will make a spacer if i can get the correct clearence from hood to manifold
That's why Aaron made the 5 pc. spacer kit for the 3.5s. 3.0 only needs a lower spacer and TB coolant bypass.
I saw that spacer kits were available but what's the tallest they offer? I could only find the thin thermal one. I'm going for one inch if possible and will be making them by hand.
Aarons spacers provide similar gains on the 3.5 cars with aluminum plenums. I can attest that the intake stays cool to the touch with them as well. Of course, the 3.5 has a very different intake from the 3.0 cars.
It'd be interesting to eliminate the temperature factor from your experiment with the CL by making a spacer out of aluminum with metal gaskets. That way you could determine how much of the gain comes from the length and how much comes from the temp drop. It may not be worth lengthening the runners on a plastic intake.
Here's a thread were someone used the 3.0 instead of the 3.2 I had but there were still gains and he did not use a thermal gasket, and there's dyno sheets for the spacer alone. http://acurazine.com/forums/performance-parts-modifications-112/intake-manifold-spacer-installed-891096/
If the 3.5 Mani fits, I would use that for the better top end if it flows better,then space it by an inch or more. Look at the power band on the dyno sheet, it's interesting.
Also weither it's plastic or not, lengthening the runner increases air velocity at lower rpm. Material should not matter until heat soak comes into play.
That is interesting. If I had a 3.2 I'd be in for one.
It all comes down to how well the original is designed. It looks like Honda sacrificed some power to fit the motor under the hood. If Nissan did the same thing there may be power there. The 5 and 5.5 gen runners bend back toward the firewall so if Nissan wanted to add a few inches they could have. Of course, Nissan could have easily added thermal spacers on the 3.5 but they didn't so...
You wouldn't believe what the manufacturer would skip on to meet budget demands. Being that these vq motors just love to breath, I wouldn't doubt it would help. The runners are are pretty long from the get-go but the issue at hand is that when we buy our bigger tb's and 3 inch intake piping we loose intake velocity. Lower rpms become less powerful because you loose the "supercharging" effect of the intake velocity. If you look at high revving monster, they usually have individual tb's per cylinder and the shortest runners possible. In a manner of speaking, the longer the runner the lower rpm the "supercharging" effect happens thus more low end torque. If we were using a big bore TB, CAI, and the spacer, we would lose the air velocity as it enters the TB but gain it back in the now longer runners. To open up more potential, you can use the metal manifold from the 02-3 Maxima and port it and the theoretical spacer for the best high and low rpm performance. Here's the science behind the spacer and the overall "supercharging" phenomena. http://www.autozine.org/technical_school/engine/Intake_exhaust.html
I absolutely believe it. I sold cars for a long time including Acuras from 03 to 06 so I'm very familiar with the cars you're talking about. I also work as a mechanic and do a lot of European cars. I've seen the cheap crap that companies like BMW, Mercedes, etc... slap together only to need major repairs after 50 to 70,000 miles. Nothing really surprises me when it comes to car companies.
There are guys here running 4" intakes/MAF tubes and seeing power gains. I'm actually planning that once I figure out another small issue I've been having with the car.
I'm curious to see if there are gains to be had on the 3.0 cars. I have a 2000 as well as my 02 but it's a bone stock auto.
I'm sorting out a few bugs myself. I just picked up a 00 max with 218xxx on it for 500. It had a new clutch and alternator but needed tires, coils, plugs, new coolant and oil. If it proves reliable I'll start the modding and what not. 4 inches of tubing is nuts, it probably fools the maf to run leaner as well as let's in more air. On these said setups, do they also use 4 inch tb's? I would imagine that if adding tubing diameter adds power then porting the 02 Mani would be good for higher flow. If anything, Nissan tuned the runners diameter to the intake and TB diameter. so if you open one the other must match.
The 02 runs a 70mmTB but the 75mm 09 TB works with an adapter and some wiring. I'm running one of those. I'm not sure what size the 2000 TB is.
The 4" intake increases the velocity even with a smaller TB. You have to retune of course because it will run very lean if you increase the size of the MAF tube. There are some detailed threads on it here if you search. There's a lot of this stuff in the "all motor" forum too.
I don't think the 02 intake will work with the 3.0 liter.
04-10-2016, 03:29 AM
