dlee275

So this weekend me and a friend have been working on installing the hotshot headers on my 02 Max. We have run into quite a number of problems but have overcome them all so far. I have a couple questions though. The o2 sensor that screws into the front bank is hitting the alternator and the wire really doesn't reach. Is that typical? Also, I ordered an o2 simulator for the secondary sensors but I don't know if I got the right one. How can I tell if I have one that can work for two sensors and how do I wire them and where would you recommend putting the box? Also, for the rear manifold which bracket do I need to remove. All the old bank is removed w/o taking either brakets off but it looks like the bottom braket (more sturdy, darker colored one) might rub on the new ones. I took off the top, flimsy one and now I don't know if I even needed too. Any help will be greatly appreciated.

Kevlo911

iTrader: (36)

You have to extend the O2 sensor wires. You can put O2 sim where ever you want away from high temps. It should have 2 outputs.

dlee275

thanks, also if anyone knows what torque the head bolts should be i would like to know that as well

getbigtony

iTrader: (1)

u removed your head to install headers? did you have to do that? well last time i replaced my headgasket on my 92 accord, i didn't have specs, so i used a 2 foot breaker bar, went around tightening slowly starting from the middle bolt and go out. just went til it felt snug. that was when i started hearing screeching sounds. but no problems now and still running good. and i didn't purchase new head studs. i used them old *** ones that was in there.

Kevlo911

iTrader: (36)

Pretty fckin tight

dlee275

I didn't remove my heads, I was just referring to the 14mm bolts connecting the headers to the engine. I was only able to use a 3/8" ratchet on those bolts, no breaker bars, and I tightened as much as possible by hand. I don't think I have any leaks. I still haven't wired my o2 sim yet though. Also, the tip of the front o2 sensor, once the header was tightened to the engine, bent a little bit on the compressor. It seems to be working but I think to get it off would be a huge job now, probably easier to remove the compressor to do it. The senor should be slightly relocated I guess but I'm not worried about it for now. I wish hotshot would have put the damn thing in the right place though.

upstatemax

iTrader: (15)

We have been asking them for a year now to move it up just an inch and a half... I relocated mine to the front collector.

SuperStasiu

iTrader: (3)

I have hotshot and we relocated the 02 sensor up because otherwise it would hit the AC. The easiest way to install these was to remove the lower engine mount and use a tranny jack to rotate the engine forward when doing the back ones. Also to remove the back mount on the engine so its easier to install the headers. Well you are only gonna use the main front and main rear 02 sensors so you should be able to figure out which ones to simulate from their. These are the 02-03 hotshot headers installed on a 2001 maxima. The hole install took us about 2 hours and that was goofing around. The install was done by blackbird

Heres a shot of the 02 simulator installed

dlee275

Yeah, it is my ac compressor not my alternator...idk what I was thinking. But I am a little concerned now b/c after a really satisfying test drive I go to restart my car while still hot and it starts and gets to about 1000rpms and then dies immediately. It does this unless I hit the gas for a few seconds and then it will idle. Any ideas? Thanks guys.

SuperStasiu

iTrader: (3)

Which 02's did you hook up the 02 simulator too?

dlee275

actually, i havent simulated any yet...the two secondary are zip tied up together in the engine right now.

Puppetmaster

iTrader: (48)

If you still need help with the O2 sim:

http://forums.maxima.org/showthread....&highlight=sim

upstatemax

iTrader: (15)

Should not be the o2 sensors, I did not have any hooked up the first week i had my headers and the car ran fine...

I would go back under the car and look for anything that could be unhooked. Did you drop the engine brace to install? If you did, you had to unhook the engine mounts if I remeber correctly. If you did, are they hooked back up? They are electrical mounts and if they don't work they can stall a car.

vsamoylov

imo that doesnt look too good

dlee275

Thanks a lot man. That will definately help. My car seems to be running pretty good except the hot start issue. I think I hear leaks though, but the car sounds so different up there now it is hard to tell. Also, I had the ES motor mounts pressed into the cross member while I had it out and those make a huge difference, and I think only automatics have an electric mount.

dlee275

So does anyone have any additional idea as to what may be causing my car to start then die on hot starts unless I hold the throttle open for a few seconds?

The hotshot directions say nothing about this but the Cattman directions mention taping a cooling line that goes to the base of the oil filter housing, did you guys w/the 5.5gens do this?

Another seemingly large disparity b/t the two sets of installation instructions are that Cattman recommends starting the tightening process from the bottom and hotshot from the top. I chose the follow hotshots here. What did you do?

steven88

iTrader: (28)

taping a cooling line? never heard of this...can you elaborate more?

dlee275

Here is the final steps in the Cattman header installation instructions...this is the only information I have about it. I looked under there and I am not sure exactly which line they are referring to. If you want all the steps I can email them to you.

Completion

1. Install bottom exhaust pipe join (“Y” pipe) and rear section with flex coupling.
2. On 02+ Maximas and I35s with the VQ35DE motor, use a small piece of insulating tape to cover the thin cooling line that goes to the base of the oil filter housing.
3. Refit existing catalytic converter.
4. Tighten ALL bolts with the cat and the two triangular downpipe flanges.Tighten the nuts where the manifolds bolt to the head last. DO NOT FORGET THE EGR PIPE & O2 SENSORS.
5. Replace radiator, plastic air intake & plastic guards, etc.

dlee275

btw...i didnt remove the radiator and had no trouble at all really w/the front bank

steven88

iTrader: (28)

OHHH, i get it now....you don't have to worry about that...the HS header design is alot different....so you don't have to tape anything

dlee275

Okay...thanks.

Puppetmaster

iTrader: (48)

AFAIK, that only applies to people with the 2nd generation Cattman headers, because the loop in the y-pipe runs very close to the cooling line. Brian Catts recommended that the line be wrapped with some thin exhaust wrap of some kind. I have some of it, but never used it because the 2 aren't really that close and would never be close for extended periods of time anyway.

IMO, regardless of what both manufacturers say in their instructions, just go with the FSM when in doubt.

Puppetmaster

iTrader: (48)

You can see the line here, the metal one with the hose:

dlee275

That diagram of torque specs and tightening pattern would have been useful to me on Saturday. I am glad now I only used a 3/8" ratchet b/c I probably still put more than 21 ft-lb on those bolts with that...a 2ft breaker bar is definately overkill.

But I was referring to Cattman instructing to tighten from the Y-pipe up to the headers and Hotshot saying headers down to the Y.

dlee275

Well I just took the Max out for a real test drive and the headers have definitely helped. The car feels noticeably faster now (almost scary). But there is a lot of noise coming from the header/ypipe area now. It is kinda of an airy noise, it is hard for me to describe it but it is about as loud as or louder than my intake w/the holes drilled in the filter holder. There is so much noise coming from the front of the car and underneath me that I can't hear my exhaust (stock from cat back) unless I am behind the car, but it is also noticeably louder, though still very quiet, just slightly more rasp and volume, maybe a little deeper.

My car still stalls on hot starts unless I slightly hit the gas for a second. If I prevent the initial drop of the rpms it is good. Any ideas guys? I figure it's got to be header related.

Also, the ES motor mounts are awesome. There is slightly more vibration at idle but the car feels so much more responsive and I just feel more connected to the car. Also, I think wheel hop might be gone and the 1-2 shift is so crisp now. Even changing gears feels so different. I think I am enjoying the mounts more than the headers even, and that is saying something.

upstatemax

iTrader: (15)

get used to the hiss from the headers, it is from a loud flex section. At least that is what I have ended with after chasing an exhaust leak for months that never presented itself...

I might wrap the flex section when I connect my EGR soon and I will let you guys know if it gets any better.

dlee275

I wonder if heat wraping the headers would help any.

SuperStasiu

iTrader: (3)

Whats wrong with it?


I doubt it, i think heat wrapping would be for people running boost

upstatemax

iTrader: (15)

I have to agree with him, it is kind of an eyesore. When you want to show off your headers all you see is an ugly o2 sensor welded in...

SuperStasiu

iTrader: (3)

Well i didnt install the headers for looks, also we relocated the bung in order to keep the AC. These are 02-03 hotshots on my 2001

upstatemax

iTrader: (15)

I have the same headers on my 2000... I also still have my AC by relocating the sensor to the front collector.

You cannot see the sensor from the top of the car, you have to get under it and it is right there.

SuperStasiu

iTrader: (3)

wheres the pic

vsamoylov

well my set of hotshot headers came in today so we will see how the install goes.

upstatemax

iTrader: (15)

Pic from above:



Pic of installed sensor:

dlee275

All you really need is determination and patience, and maybe a little common sense.

SuperStasiu

iTrader: (3)

Thats not a bad location upstate, looks good. Did you have to extend the o2 sensor wires.

BlackBIRDVQ

iTrader: (15)

upstate, those welds look worse than the ones I did on SuperStasius.... I chose that location as its EZ to install the sensor into the header, and you do not have to extend any wires at all.

My 02 is in a similar spot but little bit lower, I don't show off my engine to anyone anyways.... gotta keep up the Chicagos fastest NA Maxima title :P

To the original poster, you have exhaust leaks. Its throwing off the O2 sensor readings and the car wants to stall out. I would double check that you have all the bolts and nuts tight. Its "recomended" to double check the bolts after 500 miles or so for tightness as everything should settle in. My flex pipe makes a whistling type of a sound, but it doesn't annoy me really so I don't care. My intake makes a whistling sound also, I had a few people ask me if my car is turbocharged due to the whistle at part throttle

dlee275

Blackbird, if the car has leaks would it have to be at the engine to affect the o2 sensors? Sometimes I think I hear something like a leak but it sounds like maybe where the y connects to the manifolds.

What's weird is the past 4 hot starts my car hasn't stalled, it has dropped low a couple times but it seems to be getting better. Do you still think it could be leaks?

upstatemax

iTrader: (15)

The welds are terrable... I wanted to slap the guy when I saw the job he did. BTW, the shop is APG Motorsports in Albany NY, so anyone around there, never go to them, they are a rip off and do halfazz work!

I did not have to extend the wires at all, there is still about an 1.5" of slack if I pull on the wire. I also don't show off my engine, but I still wanted it to look good since some people do end up eyeing it.