I've got the car tuned to about 11.8 to 1 NA, I'm spraying a compucar wet 150hp shot and today when i tried it out the car just popped and spat black smoke out the back.

Am i just way way too rich? What is the deal here?

It was a definate pop sound, didn't sound like detonation. I couldn't tell if the popping was in the intake or the exhaust.

Oh and the car has 28 degrees of total timing.

I think i'm going ot wait until i get my 100hp jets to try it out anymore!

 

damn....could be bad nitrous....or running too rich

 

What about plugs, mine are gapped at 40 right now. Could it be blowing those out?

Oh yeah they are platnum ****s too. Our parts dept sucks and wouldnt' take them back after i bought them

 

oh oh...platinum is not good with nitrous u should get different ones.....ngk tr6

 

Pep boys carry them?

All i need to aks for is a TR6 NGK?

 

what about a autolite plug?

I've alwaysed used them

 

i dont think pep boys will have em but any speed shop should carry em.....i think autolites are ok but not sure

 

definalty your platinum plugs are causing your problem. I ran into the same prob when i first got my 150 NOS setup. DO NOT use the nitrous until u replace them. The Nitrous gets so hot it melts the platinum tip off the plug causing incorrect gap and the cause for poor performacne and popping now.

 

Autolite 104--they are one range colder than stock. Works great for 100+ shots and only $8 for the set.

Your plugs are likely part of the problem. You may have not had much pressure in the n2o line, so you got mostly fuel... and hence the backfire.

 

Yes Pep Boys does have them, probably not in stock though. I have ordered them from Pep Boys before, just took a day or two to get them.

The only store I hyave found to keep them on the shelf is O'Reilly's Auto Patrts.

 

Take those platinum plugs out. Autolite 104's gapped at .040 should suffice.

 

the plugs may not be the only problem, or even any problem at all. my reasoning behind this is ive been using stock platinum plugs on my 96 Z for the last 6-7 months ive had the kit on my car. ive put 10+ bottles through and never had any problems like that of which you described. im not saying they arent part of the problem, im just saying they may not be the problem.

i would also check fuel pressure, jets, and nitrous lines/bottle. any one of these could aid in the occurance of what you described. a leaking nitrous line (resulting in no N2O), too much fuel, the wrong jets (which could result in too much fuel) etc.

i will agree that you should switch to a step or two colder plugs that arent platinum. i will be doing one step colder when i do a plug/wire change, which will be very soon.



good luck!





jon

 

I went to Autolite 103's which are 2 ranges colder. I did a same day test at the track with 104's and 103's and gained 2 mph NA with the 103's . But I am runing 11.2 compression so that is probably why. I don't know what your results might be.

 

I would not have started out with the 150 shot. You want to work your way up to it, that way if there is a problem you learn before the 150 shot. I would swap the plugs also.

 

Might want to retard the timing a little before trying the 150 shot again. 11.8 to 1 is getting up there and you don't want the heads lifting. Mine did

If you haven't retorqued the head bolts in a while, now would be a good time.