ForeignMuscle

Hey Zilvians, I would like to know who is using a large turbo (above a 30r) with a rom tune such as JWT or Enthalpy. Share your results and troubles.

I have a forged short block with a factory head and a Precision billet 5858 mated to a Hybrid Dynamics manifold. I plan on using a friend to tune the engine eventually using Nistune or AEM, but I ran across a JWT ecu tuned for (and including) a lightning maf and MSD 96lb injectors for dirt cheap. I plan on running with it for the time being until my build progresses to the next level.

There is hardly any info of people using rom tunes with larger turbos. It seems that the fwd bunch tends to go this route more than we do and they seem to have descent results.

My biggest question is knowing how far to go with boost. There isn't a way for me to monitor knock that I know of and the A/F ratio is only so good for monitoring the tune.If anyone has experience with this chime in.

lazysk8er2

Chances are you will have no idea whats on the tune. I would send it back to whoever tuned it and get a retune should be pretty cheap. Rom tunes tend to run a little rich for safety measures.

Enthalpy always puts out good tunes I would def. recommend contacting them.

Overall I would probably just save for the AEM unless you absolutely must drive your car now.

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Magical Trevor

I watched Martin from Enthalpy tune my buddy's S13 with an S14 SR, built bottom end, Z32 MAF, 550cc injectors, Precision billet 5858 on a very conservative 20psi to 340whp for his drift setup. Martin knows what he's doing, and has been doing it longer than most in the Nissan scene. He's going to do cams and larger injectors around tax time and go for more power.

jr_ss

Martin is a good tuner and guy. If you have any questions contact him and voice your concerns/questions. He is a very intelligent guy and has a huge back ground in Nissan.

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My SR20VET

ForeignMuscle

Thanks for the input guys. As stated it is a JWT ecu and the tune is printed on the ecu. I'm just looking for experience or maybe tips on knowing when to stop adding boost. I'll call Ben at Jim Wolf again tomorrow.

Btw, this is not a matter of money. I bought the ecu, maf, injectors because it was so cheap i can easily resell it for more and I can run it until I am sure of the next step with my project.

ForeignMuscle

I will give Martin a shout as well. You can never learn too much..

4x4le

youll be lucky if you can get a stoich idle with 96lb msds with a nissan ecu on a 2.0

Btw, the reason I got into tuning was from blowing an sr running a jwt ecu using the maf, turbo, and injectors it was tuned for running at the boost level they said it was tuned for. Cracked ringlands on one piston and a bent rod on another. When I called them about it they told me that it couldnt have been the tune and that my engine probably just blew for other reasons.

Looking back at their tune at a later date after I knew what I was doing with tuning it was obvious that it was the tune. I couldnt believe how much timing they had, after about 15psi timing was no longer being pulled and there was no resolution after 6400 rpms.

If your doing it so you have a way to move the car, drive the car, and give it a shakedown as far as reliability goes then its something for you to consider maybe. If your wanting to do this so you can have some fun sooner, I would advise against it. You would be taking a un needed risk and I would suggest you wait to do it right from the start.

Now I know someone is going to come in here and say, "but Codyace loves his jwt tune and his car is reliable!"
I am truly thrilled for him and glad it works for him. Honestly, it is great and it could work for you too, but if these canned tuned ecus were so good, the same name (codyace) wouldnt have to be brought up each time someone speaks of their blown engine due to the bad canned tune.
I have a bucket of jwt and enthaply boards you can try out lol

Jez

I considered a mail order tune after doing a few mods on my Silvia, granted I dont have a big turbo or any other wild mods but I opted for a daughter board and some dyno time.

With my limited knowledge and experiance there is no substitute for dyno time, to many small variables to be taken into account IMO.

4x4le

This is so very true. I tuned stockish s13 sr's back to back. Both have fmics and exhausts but were still stock maf, t25, and stock injectors. Both ended up liking the exact same 10 psi the best, no gains were seen (tuned for tuned) over 10lbs, but one I had to run over 80% duty cycle on in order to get the air fuel ratios where I wanted them. The other I could literally flood out to a stumble with fuel If I tried to run that much pulse width. The timing maps were quite different too. Their graphs looked nearly identical, power, tq, afrs and the curves on all of the above however their tunes were VERY different. These were nearly identical setups!!!!!!!!!!

Now start adding aftermarket parts and built engines and see how different stuff turns out. Something as simple as maf location, or the age of the injectors seem to be vital.

inopsey

you can add additional devices to monitor knock such as a knock link etc. KnockLink G4 - visual detonation warning — Link Engine Management Systems - plug-in & wire-in aftermarket ECU's

a/f is not a good way to monitor a tune you can be stupid rich (10.0 afr) and still knock if you have too much timing for your fuel.

4x4le

I agree with the 2nd part of your post (that I didnt quote) but the product linked is junk. I havent personally used that one but knock lights are nothing new. It used the factory knock sensor which is not a high quality listening device (ist freaken junk actually) and I disable knock sensors on my tunes (due to them being junk) and I unplug them and unbolt them (piss on them) and then throw them away. (because they are junk)



Now, with all that being said, some cars do have better knock sensors than others and these knock lights could have some potential with a higher quality sensor installed on the engine. You wouldnt want to try to bring that new sensor into the ecu, but just have it as a standalone knock monitoring system. My ears personally are very sensitive to knock and I like wearing ear plugs in order to hear it better. It is odd how wind and road noise as well as exhaust get muffled when the detonation can make it right past ear plugs. Another trick is squeezing my nose and blowing out (but not letting air excape) to the point my ears pop. Knock seems louder to me then too. Now this isnt scientific, and I dont consider my ears to be calibrated high quality listening devices but they do seem to be more consistent than anything else I have used. Some peoples ears might be junk though lol

inopsey

i havent used this product either since its quite new but dont be so fast to dismiss this.
the knock link comes with its own knock sensor. this works on any car since it wires directly into the knock sensor and 12v. its also self learning but cannot do closed loop anything. you could log voltage from it as an input with a haltech or similar ecu.....

link/vipec are an interesting company and one of the few companies that offer any type of knock feedback with their ecus directly that is actually worth using for tuning. i know the local vipec tuner swears by his knock ears but uses the vipec knock block(different product) because its more sensitive to knock that his own ears.

4x4le

I read something about using a factory sensor with it on the link on the page but if it does come with its own sensor than that is cool. Many of the lights and sensors pick up allot of phantom knock. You end up finding your self ignoring them quite often, they are good for if you get fuel at a different station and all of a sudden it turns into a christmas tree, or its a hot day ect and keeps blinking.
It is really hard to hear knock when your running down the road, but for the same reasons it is hard for a sensor like this to be accurate when running down the road too. Harmonics are calibrated in them sitting still, but your under load going down the road.

ForeignMuscle

Crazy as it sounds Brandon I found the post from '07 where you spoke of your engine blowing up. I have to say though that 28psi seems like that might be a problem for any pump gas tune.

With that being said, I definitely don't want to push my motor hard with the rom tune, but i figured 10-15psi and around 400hp would be fine but you make me wonder..

I paid $300 for everything and I have a guy already who said he would give me that for it so I knew it wouldn't hurt me if I decide to sell it.

Clark at jwt sounded confident in the setup but i definitely dont want to risk my investment. You and I both know what I've been through and it wasn't cheap lol.

4x4le

Sure does, but before I knew much about turbos and I had the go ahead from the provider of the ecu, it seemed reasonable to me.

either way iv spoke my peace about it and it was not the last engine I have seen get lost to either a bad tune from either a pre tuned ecu or even someones custom tune. If your willing to roll the dice its not like the chance is huge that your going to be screwed, but its much larger than if you dont roll the dice.

ForeignMuscle

Yea I understand. If they told you that was safe that was messed up on their part. I may just sell the combo if I can't get a straight answer or at least a way to datalog the car. I actually just wanted it to have a way of running the car with proper fueling. I'm not even positive that 370's will be sufficient for a 4psi spring.

4x4le

It sounded far fetched to me and to some of my friends but I figured who was I to argue. They told me boost does not matter as long as I dont go lean.

Anyways, its embarrasing that it happened but Im proud of the amount of people I have been able to help not make the same mistake.

Xaser

Im Running a GTK350 i dont know if is bigger or not to you, buy im go on megasquirt.

ForeignMuscle

No need to be embarrassed man. You were young and it was new to you. I was a noob only a year ago as far as the SR goes and I owe thanks for the majority of my knowledge to you.

I'm still pumped about you tuning my car regardless of what I decide until then. Big numbers will be had, but more importantly it will be a great car for what I use it for.