It can pull some timing for bad gas/light knock but it is by no means enough for the knock you could encounter running stock timing and a large shot.

A friend of mine ran all day long @ the track on 100 shot and he forgot to switch his UTEC to the N20 map. Lucky for him he put in some 110oct race gas for good measure, Im sure that saved him from knocking and damaging the motor.

Dont rely on the stock ECU even for a 75 shot

 

No, if you are going over 100-125 shot, you need 2 step colder plugs. Nitrous being cold has nothing to do with anything, it's the heat generated by the combustion process that leads to problems. Nitrous EGTs increase much more violently over FI and you can melt plugs if you can't get the heat dissipated fast enough.

And the whole "colder plugs = worse performance" is not totally true. Performance loss will not be from the plug, its how clean the plug is. So if you have 2 step colder plugs in your car for a 100 shot, but you dont run the nitrous in it from time to time, then yes the plugs will fowl out. But to simply swapping the plugs in and say that performance will drop is wrong.

 

I disagree with you-from experience in other applications 2 step colder plugs are not needed for most that run them. Ive never heard of any reputable shop recommending 2 step colder plugs for any stock block duty, N20, or boost. Whatever works for you!

Why would EGT's increase so violently? If the timing map is too retarded then yeah, but I dont see it running hotter than some big boost. Anybody have an N20 EGT's on ohere?

 

As I've already mentioned multiple times and even in this thread, you're doing it all wrong. How are you going to compare the DE engine to the HR engine? Please don't misinform the others by comparing two different engines and their stock plugs' heat range.

And unless you're spraying like a 200 shot, I'd stick with 1 step colder plugs. As Alberto said, it WILL lead to decrease in N/A performance and rougher idle.

The ECU can and will automatically retard timing if it sees any sort of trouble. However, keep in mind that this will not be enough to save your engine from the user's inability to keep things at a safe level. In addition, this only happens after it senses trouble. In other words, by the time ECU decides it's time to change the timing, it may be too late.

There's a reason why we have the option to get a tune. If you don't want to (I haven't), that's fine, but you're risking a lot more than you're ever going to want to.

 

If a plug is so cold that during normal combustion it cant get up to ideal temp and burn gas/combustion deposits-it will in turn "foul" faster and run like crap. That is exactly what will happen to 99% of Z owners spraying 75-150 shot occasionally. Therefore IMO too cold of a plug = worse performance. Agree to disagree.

 

Each to their own, not running 2 step colder plugs is just increasing your probability of something bad going wrong. IMO, running 125+ shot on a stock internaled 3.5L isn't a great idea anyway.

I made multiple runs with 2 step colder plugs on my SBC naturally aspirated and the plugs looked fine, as long as you run the car hard from time to time. Then a flick of a switch, and 200 HP was there for the taking. I'll try to pull my dyno graphs out of the engine dyno software sometime this week in which we monitored EGT with AFs.

 

Couldn't find a single vendor selling One step colder plugs for the HR's. Also, I'd rather have 2 step colder plugs over 1 step colder just for the sake of peace at mind...

Also, Sam at GTM gave me a call and asked me why I was ordering 2 step colder plugs & not 1 step colder - I told him I was planning on running a 125 shot of nitrous and he said exactly this "Yea you would definately want to go 2 steps colder" I'm sure GTM is a very reputable shop, is it not?

Oh forgot to mention, I wouldn't care about the loss in performance N/A; Wouldn't be that drastic of a drop in HP...
If I was taking my car to the track, I would spray everytime; N/A performance wouldn't really matter to me, however, there are those who take pride in how fast their car's are N/A...
But I wouldn't care about that; I'm going on spray to be faster, No reason to mope about the car being slower n/a.. Just my .02

 

still wanting to know what these NGK plugs are that claim to be two steps colder, considering NGK doesnt show a plug for an HR fitment.

 

I spoke with Dynotune and GTM today...

Sam at GTM claims he has both 1 step colder and 2 step colder available to ship. His website only says 2 step but he told me to order the 2 steps and just include a note in the message that I want the 1 step colder plugs not the 2.

Not sure if hes sending me on a wild goose chase

As far as the timing retard, I agree that I SHOULD retard it a few degrees one or two degrees for every 50hp or so. BUT at this time I dont have the cash for a good tune so Im just going to risk it for a little while. Im just going to hope and pray that she holds up.

I DONT spray very often, maybe once or twice a month for a few seconds so this will help my cause. If I was taking it to the track every weekend it would be a different story.

Back to the plugs: Sam at GTM seemed a bit sketchy today about the plugs so Im going to call NGK and DENSO direct tomorrow and see what the deal is. Plus GTM wants $180 for a set of 6. Im sorry but thats about 30$ more than I paid for the install!! Cant afford that

And I still think and so does everybody I know, including a few shop owners, that 1 step is plenty for the shot Im running now. 200+ Id go with two steps colder but anything up to about 150 or so should be fine.

 

On a 100 shot on my car which is tuned by Uprev I was running way to lean. Even after they added more fuel and pulled 3-4 degrees it was still hitting 14's on the AFR. Randy had to go +5 more fuel just to hit the 12.63 afr target. He advised me that running mean and lean like that would generate very high EGT's. I would highly advise you spending the extra money and having the car tuned by them for NA and N20, it really gives you piece of mind. Plus theres alot of hidden power in those HR's.

When I spray my 100 shot I flick it to map 5 and spray away. He also pulled timing only in my window switch range from 3600-6000, this way I can just stay in it untill redline and get my timing back after 6000rpm. I feel much more confident spraying my 100 shot at will knowing that everything is running in spec. Without tuning you have no idea whats going on.

Ive been thru 6 10lb bottles in 1 month!!!!

UPREV FTMFW!!

 

Hey twitch you wouldn't have a name and a number of a good guy over at uprev would ya? You had quite a bit of tuning on your Z! Not sure if the HR needs quite as much. Of course I have no idea until I pull the plugs and check the AFR etc.

 

A local HR owner had nitrous installed, races almost other weekend here at HRP. I believe he had a dynotune kit but I may be wrong, shooting with a 75 and 100 shot, he told me his dyno numbers I believe they were something like 350 whp and 330 torque and that's with 75 shot nismo exhaust and test pipes..

He said when he bumped up the shot to 100 that his clutch started to slip and he ordered a competion clutch and he said he abused the hell out of it and the engine held up awesome for 30,000 miles. After that he said that his engine started to feel sluggish with some misfiring, he found oil on plugs (which I believe were stock), and the engine started burning oil. He also said that cylinder #1's ring was bad..

He sold the car and bought an evo x. He said the Z held up very well with the kind of tracking he did..

 

You should get 1 step colder plugs for anything around a 100 shot. If you spray up to a 150 shot, maybe you can get the 2 step colder ones. Also, @ GTM wanting close to $200 for ****ing spark plugs. I hope these come with lifetime unlimited warranty for that kind of price. Why don't you guys just ask for the part number for the "2 step colder" and "1 step colder" plugs that GTM carries?

 

Few points i would like to make :

-We do have in stock one and two step colder plugs available for the hr and vhr .
-We have these plugs in the oem packaging which is 27.78 a plug and a private label option for 23.97 Bothe are NGK IRIDIUM PLUGS
-Just because these plugs are being sold at these prices, It does not mean that they don't cost a lot more then what we are used to (DE PLATFORM) they just cost a lot more and not very easy to come by .
-My recommendation still remains as before for a 100 shot i would go one step colder anything over that i would do two step colder. It is better to be on the safe side, We have been forced to use 2 step colder plugs on our turbo cars setup due to the lack of the availably of the one step colder plug at that time with no issues .


SAM

 

Sam what is the brand and part number for the 1 step colder plugs for the 07 HR? I would like to order them from you but your website only shows 2 step colder. Thanks!

 

Could it be ngklfr8aix?

 

The one great thing about a wet kit is having fuel jets. You don't HAVE to tune a cars ECU on the fuel side, you can simply go to a larger fuel jet if you need more. That's also why I like the Zex kit, because the kit was designed and tuned for the jets on an actual HR engine.



NGK does not make a HR specific plug unless they JUST came out with one.

The Denso 1 step colder plugs are about $8 each

I still want to know the part number on these $30 NGKS