OnOiShNo0dl3Z

iTrader: (2)

So I bought my NWP spacers from a member here on the org about a month ago and finally got around to installing them today. Due to lack of tools, I was able to install all spacers but the throttle body one which requires allen keys to loosen and torque down.

I started the car and let it warm up and ended up not having any rough idling or high idle. One of the main things I was hoping to experience was the decreased engine temps.

After the install, it was about 10 PM. I took a half hour drive in the city, not really any spirited driving and when I got home decided to check the intake manifold expecting it to be hot but not so hot that I couldn't keep my hand on it for a good 5-10 seconds. It felt just as hot as it had before I threw on the spacers. It's hard to keep my hand on there for 2 seconds without getting burned.

Obviously, this isn't an accurate way of measuring engine temperature, but due to the post quoted below found in this thread and the NWP website, I was expecting it to be much cooler. Is this normal?


http://forums.maxima.org/5th-generat...p-spacers.html

The drive:
Mostly city driving under 2000 RPM in Philadelphia
Lots of stop signs
~30 minutes of driving
Outside Temperature is about 75-77 degrees

Rods03Max619

iTrader: (5)

Odd I do like a hour and mine be still pretty cool to touch,but wouldn't care either way as long as I feel the power difference Im good...

T.One

maybe its because of the TB spacer not being installed. I think its still being heated up by the coolant.

Alex_se_r

There are coolant lines that go to the throttle body, I would recommend you bypass the throttle and direct it back to the block.

I did it when I changed the sparkplugs,

Then again I live in Texas, we don't get freezing
temps like you would.

knight_yyz

iTrader: (40)

it has nothing to do with the coolant lines. They warm up the TB in winter. My temps didn't go down either, but I assume it is because I have headers. But I gained 25 hp in the midrange which is what matters to me

OnOiShNo0dl3Z

iTrader: (2)

Yea after some research, I felt i'd rather not do the coolant bypass, but I still don't think that's the reason. I don't have headers so that shouldn't be the case. I'm going to go check out lines and stuff. I would assume if I somehow messed up my hoses specificallly for coolant, my car would overheat in that half hour.

Also, I have a quick install question that I want to confirm. The support bracket for the UIM found towards the firewall holding up the elbow needs to be kept off in order for the spacer'd UIM to fit correct? That's how I have it set up right now, and just wanted to be sure of that.

I might put on the TB spacer today if I can get the tools, but should I be ok putting it on with the UIM bolted down? It shouldn't stress it so much that it could crack the UIM would it?

95VQ30

Mine stays relatively cool, especially compared to before the spacers

NmexMAX

iTrader: (22)

Got a dyno comp for that? Wow.

OP, pretty sure you're overreacting.

1.) Coolant (ECT) temperature isn't affected.
2.) Air from the intake manifold is affected. (difficult to quantify aside from tossing a TC in the IM).
3.) IAT's aren't affected immediately, only as they enter the heads from the assumed to be cooler IM.
4.) Added IM volume seems to help output as well.

I've also read numerous posts stating it was cool to the touch. Mine isn't either. I left out the elbow to IM spacer, but either way, not a big deal.

nelledge

iTrader: (6)

Correct. You would have to modify the bracket to install it with the spacers. (Elongate existing holes and add a couple washers to space it out.) Or make a new one. Either way, it's not necessary and would be a lot of work.

Rochester

iTrader: (3)

Yep. My mechanic did some customization to get the bracket re-installed. A good mechanic can think outside the box and make things work.

You know, "Cool to the touch" is a pretty subjective measurement. Outside temperature has a huge impact on that. Bring your car up to temperature during the winter months, then pop the hood and give your IM some of that big-handed man-love. You'll be fine. Do the same thing in the Summer, and the result will be quite different.

MrEous

iTrader: (11)

Notice the underlined part of the statement above? The 2 cars were idling next to each other...not driving around.

Radiator air flowing over metal will heat it up. Spacers are designed to keep the higher block temperatures from creeping up into the intake through thermal conduction. Spacers cannot prevent higher air temps from being absorbed into the intake manifold metal.

Flanker84

Do the Coolant Bypass if you want to avoid a future problem with your ECU.

If the gasket in the IACV starts to leak and the coolant reach the IACV motor... your ECU will become toast.

Also, this spacers are a really good mod even when the IAT sensor it's receiving the heat from the engine?

OnOiShNo0dl3Z

iTrader: (2)

Yes MrEous, I did notice that it said idling. I just assumed that the engine gets hotter when idling vs running.

After a half hour drive today, it didn't feel too bad but after letting it sit for about 20-30 mins after driving, it was once again too hot to hold my hand on for more than 2 seconds, which I find a bit weird that it got worse when the engine was off for a while.

Rods03Max619, you said yours is cool to touch after an hour. Is that an hour of idling or driving? If driving, is it mix of city & highway or mostly highway or mostly city?

OnOiShNo0dl3Z

iTrader: (2)

Where are you getting this from? If I should do a coolant bypass to avoid future ECU problems, then every maxima owner should do a coolant bypass.

I'm sure there are maxima's with more mileage than yours not running a coolant bypass that are avoiding ECU problems.

The coolant flow design through the TB was from the factory. Many people don't have coolant bypasses and some with the NWP spacers don't even bother to put it on and a very large majority of them don't have ECU problems.

Gizm0

iTrader: (1)

When the car is standing still, there is no moving air to remove heat from the engine, therefore air in the engine bay gets hot. The cooler IM then absorbs some of that heat, not from heat conduction, but rather from radiation from other hot surrounding parts. Just my 2 cents...

BTW I ordered the spacers 2 days ago... I can't wait to install them

Flanker84

I found this information right here in the forum. I got the 5th gen with the vq30 and I read enough threads about problems with the problem caused by the coolant leaks in the IACV to take the action to do the Coolant bypass. I want to avoid this problem also I live in a tropical zone (so freezing temperatures will never become a problem here).

If you want to keep your engine in that way, fine. It's your car, I respect your opinion and I only give you a suggestion for avoid a possible problem.

Greetings

OnOiShNo0dl3Z

iTrader: (2)

But if like mentioned before, that when it is idling for half an hour, the IM was cool to touch, shouldn't having the engine off actually be cooler than letting it idle?

Good luck with the install. Make sure you cover up the intake ports. My friend dropped a bolt while we were installing and luckily it didn't fall into the intake ports but somehow onto the tranny instead. I was just glad that I covered up the intake port.

NmexMAX

iTrader: (22)

He has an 02+, and he does not have an IACV. He has TBW.

Flanker84

Thanks for "show me the light" and show me my mistake.

Greetings

Alex_se_r

Think about it for a second... He does NOT have the spacer for the throttle body installed, the coolant lines are still present and will HEAT up the throttle body regardless if its winter or not! The elbow is bound to absorb that heat just as the throttle body with HOT coolant running through.

I did the coolant bypass to my SR20DE along with Outlaw Engineering spacers and it did wonders... I dont think they even recomend the bypass in their instructions.. See link below


http://www.outlawengineering.com/faqframe.html

I don't feel the need to keep the throttle body cool, can I buy the intake manifold spacers only?
This is a common question made by people that don't fully understand the operation of the system. The throttle body spacer is not meant to keep the throttle body cool, but is meant to keep the intake manifold insulated from the heat of the throttle body. Remember that most throttle bodies are heated by engine coolant to keep ice from forming in cold climates. This heat transfers from the throttle body to the intake so that the intake is now effectively heated from both ends. If we sold intake spacers only, we would only be providing half the system. If you simply must have the manifold spacers only, please contact us.

I did both and I had no problems at alll.

Froggmann

iTrader: (6)

Do the coolant bypass It does help keep everything cooled down somewhat when 195* coolant isn't being pumped though the throttle body. It's just a simple brass fitting Aaron sells with the kit If you contact him I'm sure he'll tell you what size the fitting is as well as the required bolts. Hell he might even just send it to you because that is the kind of guy he is.

As for underhood temps, once the engine gets heatsoaked it won't matter what kind of insulators you have on it, it's still gonna get hot. When I'm sitting in traffic AIT gets to about 135*-156* F depending on the weather and it take s a few miles of driving to bring that down to the more customary 10-15* over ambient temp )e.g. it's about 75* F out my AIT will sit around 85* F).

Regardless with the lengthened runners you will feel a bit more power and at speed you'll have a little less power drop off from heatsoak.

Alex_se_r

Does any one know if the 3.5 Maximas have some kind of Temp sensor at the throttle??


I did not need any special adapters to by pass the throttle, all I did is disconect the line that comes from the (front) water neck to the rear where the return line from the throttle would be. The line is long enough and I used all the OEM hardware and prob the most important, NO KINKS in the line

NmexMAX

iTrader: (22)

No temp sensor at the throttle.

I did that (this by-pass) when I first got the car (October 2004). Used some fittings from Lowe's, haven't looked back since. Down to -15ºF here in the winter, no problems.

I have Aaron's hardware that is included with the spacer for anyone who wants to pay shipping since i didn't and wont use it.

Alex_se_r

Thanks for the quick response, I was worried that it did have a temp sensor and would affect MPG's!

I did it two weeks ago and we have had 100+ degree weather for 16 days this year in TX, I have yet to encounter any problems.

Now if I could only find a nice 3" intake pipe.


Apologies to the OP, I didn't mean to get off topic.

NmexMAX

iTrader: (22)

http://www.siliconeintakes.com/index...ca62120bb5727c

Or http://www.siliconeintakes.com/ and look at their Al pipe.

T.One

Well anyways what i was saying was since the hot tb is still metal to metal, the coolant is still heating up the mani. Sooooo, if you put the spacer on it should help that out by not heating up the mani.

FlawleZ

iTrader: (1)

Look I just did the spacers about a month ago too and what I found was the intake manifold will be cool to the touch if you check JUST after you pull over from cruising. I'm talking moderate speeds like 45-75 mph consistently for a few minutes. If you park, let the car sit for a while, then pop the hood to touch them, you'll get burned they'll be so hot. The difference is the airflow once at speed. They're isolated from the engine so they're much more susceptible to cool down from ambient air passing through. Once parked, there's no airflow and thus they will heat right back up to nearly as hot as the block itself.

Be sure to install the TB piece as I too didn't install that the first time then came back later and installed it and I could tell a difference with the TB spacer added alone. I actually have yet to put the two piece lower intake manifold set on as I was in a hurry and couldn't pull the lower plenum at the time.

My results from the spacers (without lower 2 pieces AND TB piece) can be found from when I ran at the track again here:

http://forums.maxima.org/1-4-1-8-mil...ack-1-4-a.html

14.6@93.79
vs
14.4@95.02

I plan to run again this Friday with the TB piece installed. Hopefully I can get the timing advance between now and then and maybe I can see 14.2's with my slushbox and still stock exhaust manifolds all the way to the muffler.

knight_yyz

iTrader: (40)

I somehow have to question the fact that people think the coolant bypass can make a huge difference. A 1/4 inch inlet/outlet of hot coolant is not going to heat up the intake manifold to temperatures that are going to burn your hand. Sorry but it isn't possible. I'm not saying the coolant bypass doesn't do anything, but there is no way that a tiny bit of hot coolant can warm up that much surface area to the point of almost causing your skin to blister.


Here you go Manny, run 9 is headers and tune, run 12 is spacers with new tune

As you can see the area under the curve improved an average of about 20 hp and TQ Peak numbers did not change. I'm hoping peak #'s will improve with the block plate and custom BBMAF and new tune

OnOiShNo0dl3Z

iTrader: (2)

PM sent about the fitting

NmexMAX

iTrader: (22)

I totally agree.


Come to think of it, I think that's where the majority of my area under the curve came from.

My peak didn't go up much at all when comparing my pre-spacer dyno to the one shortly after... but area was increased dramatically.

Awesome, and now definitive.

Rochester

iTrader: (3)

Or spend absolutely nothing and simply loop the little coolant hose from the outlet back to the inlet.

/bypassed

OnOiShNo0dl3Z

iTrader: (2)

Wow good point Rochester. Can't believe I didn't think of that at all. I'm assuming you've been using this setup for a while with no ill effects? Did you cap the inlet and outlet and what size caps?

Edit: Would the caps even be necessary? I believe that the coolant is separated from the air flow leaving the inlet and outlet on the TB open wouldn't matter.

Rochester

iTrader: (3)

It's been like that most of the time since the spacers were installed almost 2 years ago, without incident.

I don't know why I capped the inlet and outlet around the TB. It just seemed the right thing to do. I also sprayed some WD-40 into them, to protect against rust. Again, I don't know sometimes why I do overkill crap like that.

The caps... just buy a $2 pack of assorted caps at the auto store and pick out what works.

Alex_se_r

Quote:

Originally Posted by knight_yyz

I somehow have to question the fact that people think the coolant bypass can make a huge difference. A 1/4 inch inlet/outlet of hot coolant is not going to heat up the intake manifold to temperatures that are going to burn your hand. Sorry but it isn't possible. I'm not saying the coolant bypass doesn't do anything, but there is no way that a tiny bit of hot coolant can warm up that much surface area to the point of almost causing your skin to blister.

I'm not saying, nor do I think that hot coolant through the throttle body is the sole cause of heating up the intake manifold to skin blistering temperatures. There are too many variables that affect intake manifold temperatures.

The OP stated that his intake manifold was too hot to touch for more than 2 seconds even after he installed NWP spacers (w/o the throttle body spacer). Once again there are way too many variables to diagnose his high intake manifold temperatures, and even if ALL the spacers were installed and the hot coolant was by passed, high temperatures are still possible.



From Outlaw Engineering;

I don't feel the need to keep the throttle body cool, can I buy the intake manifold spacers only?
This is a common question made by people that don't fully understand the operation of the system. The throttle body spacer is not meant to keep the throttle body cool, but is meant to keep the intake manifold insulated from the heat of the throttle body. Remember that most throttle bodies are heated by engine coolant to keep ice from forming in cold climates. This heat transfers from the throttle body to the intake so that the intake is now effectively heated from both ends. If we sold intake spacers only, we would only be providing half the system. If you simply must have the manifold spacers only, please contact us.

But I plan to bypass the coolant passage in my throttlebody?<>
Outlaw Engineering does not feel that bypassing the throttlebody coolant passage is a very elegant solution to throttlebody heat for many users. This often leads to rough idle, increased fuel consumption and possibly higher emissions. Many TB's contain thermosensors that would never reach operating temperature. It is similar to running an old carbureted vehicle with the choke all the time. Also, there truly is the possibility of ice formation in the TB during the colder months without this system. With the addition of an insulator, the vehicle can operate as it was meant to and the intake will remain cooler. .

Outlaw Engineering ,feels there is no need to by pass the coolant as there are many throttle bodies that have Temp sensors, which may cause other issues. But as NmexMAX confirmed that is NOT the case on our cars.


To sum things up

* Spacers are designed to PREVENT as much heat absorption (metal to metal contact) as possible but will not eliminate all heat. (heat radiation from the engine)

* By passing the Hot Coolant from the throttle body might cause some negative effects on some cars. (not the case here)

* The Throttle body spacer is meant to keep the intake manifold insulated from the heat of the throttle body. (if the Hot coolant is still flowing through)

*Even if all the spacers are installed and the coolant by passed, it is still possible for the intake manifold to get too hot to touch, (too many variables) but doing so will eliminate two key heat sources.

* Coolant by pass is free, you can use all OEM hardware, and will cause 0 issues with the 3.5 VQ engine.

So why not do it?? It takes all but five minutes to do, and will remove another heat source from the intake manifold.

Just my .02

Alex_se_r

Fixed that for you.

Rochester

iTrader: (3)

Pretty darn good summary of the TB bypass for only your 8th post on the Org.

Nice.

Aaron92SE

iTrader: (128)

If you are still having a hot intake manifold after installing the Spacers, it is due to the ambient engine bay temperature, not the heat transferring from the heads. Regardless, the intake manifold will still be cooler than before. But if your intake manifold does heat up due to high engine bay temperatures caused by idling or slow city driving (minimal airflow), then having the Spacers installed will allow the manifolds to cool back down VERY quickly if you kick on your cooling fans or make one pass down the track to get a little airflow.

When we did all our testing on these Spacers, we kept the hood shut the entire time and let the engine idle. This is the most extreme test we could do to get the intake manifold heated up as much as possible. The result was still 40 degrees cooler than before. We noticed the highest temperature we could get the UIM to without the Spacers was close to 150 degrees with this testing method. With the Spacers installed, the UIM did not exceed 110 degrees resulting in a 40 degree reduction. This test was done on a sunny 59 degree day. In the dead heat of summer, the 40 degree reduction is still there, but the engine bay temperatures will be higher. But if you cruise for a few minutes, then pop the hood, you'll notice your manifold will cool down pretty quickly.

FlawleZ

iTrader: (1)

Thanks for posting the conditions for when you tested the spacers. I was wondering those myself.

Wonder what the UIM is at when temperature outside is 102 like it is here in the summer.

Aaron92SE

iTrader: (128)

I don't have exact notes here in front of me when I did testing in 90+ degree weather. You'll still see a 40 degree reduction though. But the temps might be slightly warmer than when we tested in 59 degree weather. These hot summer months is when you desperately need the NWP Thermal Intake Spacers. The hotter it is outside, the worse the heat soak and the more of a gain you'll see. With our Spacers, you'll notice that the car won't get as sluggish as it did before when driving in hot weather.

Rochester

iTrader: (3)

It would add interesting stats to this discussion if someone with an IR gun would shoot their IM at idle with the hood open/closed for a period of time, or after driving hi-rev for a while on a super hot day.

Even more on-topic, if two people could do it: one with spacers, one without. I remember Trooplewis did that for me with the front water pipes, which if I remember correctly, got up to 235 degrees F.