so we were on the dyno trying to get the na tune dialed in with my new 4150 tb and vic jr to get the thing ready for bradenton. we decided to mess with the nitrous and do a pull and yes i know the dyno isnt the best place for nitrous tuning but trying to get a ballpark and no tracks are open here yet. well im running a edlebrock rpm performer II plate with n2o outlet solinoids from my old direct port. anyway here is what happened on the first hit.

http://www.youtube.com/watch?v=xH87B...el_video_title

we believe it lifted a head bc it blew the hose off the radiator. i got to do a leak down test tomorrow or the next day. we are not sure if the timming tuner failed to work or if the shot was much larger than advertised. it was supposed to be a 200 shot brought in progressivly (fjo) starting at about a 150 hit. the jetting seems odd and very large for the edlebrock plate. they call for a 85 jet for the 200 hit, that seems huge to me compared to other plates but im new to the carb plate game. do you think the shot was likely much more than a 200 or that it was a failure from the timming tuner? anyone with experience on the jetting of these plates? there is no way to monitor the timming being pulled live correct? anyway to check to make sure its working? or once i get it fixed just start small on the jetting and pull timming through hp tunners then add a bit and activate the timming tuner and see if i get a loss in hp to see if its working? i dont do the actual tunning part so im not sure on how much timming was in it but nothing timming wise was changed from last years direct port 200 hit.

car did 520rwhp na and on that short hit did 667rwhp 756rwtq and n2o is being feed by a stand alone cell with q16 in it and 93 in car.

 

Seems to me that would be more like a 300 shot but I don't know, maybe someone who has actually run a shot that size can chime in.

 

ya it seems big i have the spec sheet that came with the plate and it says 85n 85f for a 200. 93n for a 225, 102n for a 300, and 116 for a 400. but i know guys in these jet limited classes getting like 225+ from a 82 jet, just hard to believe theres that big of differences in the plates.

 

what was the whole tune up? jetting, psi, plugs, timing pulled?

 

Jetting was 85n 85f 900psi bottle pressure. 8psi fuel pressure on the stand alone. And timming tuner pulling 8 degrees if it worked right. Br8efs plugs gaped at .028

 

The car restarted and I was able to drive home with no over heating or drivability issues also

 

insanely rich with square jets and 8psi fuel. probly overtimed but don't know what you are pulling timing from.

my baseline for this year with the standalone was 39n x2 35fx2 with 6psi flowing and 950psi on 20* timing and br7efs. upping it after car gets totally lined out on the 100ish shot.

 

also no wideband? check plugs after the hose blew off?

 

It was definably rich it went like 10.5 on that hit and you can see the black smoke. I need a smaller fuel pressure gauge I have a 0-100 gauge on it from when I was running high fp last year. I haven't pulled the plugs I plan on it as soon as I get home, it was 930 last night when it happened so we just tried to get it home didn't have time to diagnose it yet.

 

would have prolly had more evidence right then. what was base timing before you pulled the 8*

 

That jetting is a bit high for our standard jet chart for this this type of application.

For our 200 hit the nitrous side should be a 82n.

I would suggest going at it again with a wideband, more accurate fuel readings, and a smaller shot size in order to dial it in a little at a time.
Pull the plugs and check them asap to get a true reading and then work your way up.

Keep us posted and let us know what you find out!

Clay @NX

 

28 degrees on the na tune

 

damn dude so u not making the lsx day at dynotune. was looking forward to seeing it.
i got a nos plate kit for mine now.

 

If you already drove the car home the plugs are not going to have any answers for you.

Start with a leak down test.

If nothing is hurt, then make pull on motor (or a track pass) and then make another pass with the timing tuner on and make your making less power ( slower mph) This will verify the timing is being pulled.

The jetting on the plate is simply not right. While an 85N jet may be what the plate requires for 200hp ( probably more in the realm of 210-240hp worth ) a square jetting pattern is incorrect on this plate on 8 psi.

Ill shoot you a PM with a little more info.

Graham @ N20

 

there was a wideband in the car and though the dyno. na was 12.9-13.0 and it went 10.5 when it hit if it wouldnt have messed up we would have obviously turned the fuel back. im new to this low pressure stuff and the effects every 1 psi has compared to a high pressure spring. thanks for the help.

i may still make it. im gonna scramble to get it fixed for bradenton in two weeks to run na down there if it is hurt.

i guess i could do that, pull the fuel pump fuse bypass the fpss and pull the bottle, then activate the system and do a pull. controlers should still activate correct (fjo and timing tuner)?

fuel will be turned back to a true 6psi any idea on how much smaller you would go on the fuel side than the nitrous to start with? if i end up back to an 85n do you think im still ok on the b8efs plugs or should i go 9s? also the plugs had alot of run time and na pulls would i have gotten much of a reading anyway?

thanks for the help everyone

 

also has anyone seen many heads lift on arp studs or do you think it likely was the mls gasket blowing? has anyone seen them reseat and be ok? i have heard its possible?

 

Give me a call here at the shop. I think with a little direction we can get you lined out and headed in the right direction. 254 848-4300

Graham @ N20

 

While not an n2o car a buddy of mine's turbo car lifts the heads almost every pass. That is at 22psi and stock head bolts. Would have swapped to arp studs but the car never has a problem and the heads reseal lol. He doesn't change anything unless it breaks.

 

I have had this happen with ARP head studs and Cometic gaskets. Sprayed the motor at the track, it over heated on the way back to the pits. The plugs looked fine, and I ran it for awhile and it didn't over heat again. I knew it had lifted a head but I was in denial because of the work involved to fix it. Then I sprayed it again and the engine blew coolant out of the radiator. I pulled the head when I got back home and it had lifted the passenger side head gasket.

 

If it lifted the heads. Drain your oil. if you have water in there then it lifted. And if your plugs have green specs that look like crystals on the plug that is a sign its lifting to. I had that problem at LSX in memphis and Dave helped me@N20 outlet