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quick question tonight thanks(n20)

  • Thread starter Thread starter 97gtblue
  • Start date Start date Oct 25, 2005
9

97gtblue

New Member
Apr 11, 2005
283
0
0
pensacola,florida
Oct 25, 2005
#1
  • Oct 25, 2005
  • #1
i need to know a few questions...i recently blew up my intake and i replaced it,and i melted to spark plugs,and one of my rocker arms came off and was laying in the top of the head..i got all of that fixed,and i wanna know what made my car backfire...i run stock timing with a 150 wetshot,with colder plugs and 93 octane... any info i appreciate...i just got done putting my kit back on and i wanna go test it out but im afriad of it backfireing


thanks everyone:SNSign:
 

MyEarsHurt

New Member
May 21, 2004
918
0
0
Oct 25, 2005
#2
  • Oct 25, 2005
  • #2
150 shot! I think thats the problem! A lot of people on here run like a 100, 125 seldom at the track. But a 150, wet shot, with a plastic intake, you are asking for trouble. Do you have a window switch? If not, then you may want to invest in one, or that will for sure happen again. Bump it down to 100 or 125, it will last longer.
 

streetstang03

unModerator
Dec 27, 2003
0
1
0
the dark side of the moon/home of the 1999, 2003,
Oct 25, 2005
#3
  • Oct 25, 2005
  • #3
combo of 150 shot, bad plugs (have to replace more often w/ nitrous), not running the safety extras, bad A/F ratio etc.... and the fact that you were running [size=+2]STOCK TIMING![/size]

you didnt have a dyno tune did you?
 

Orions98GT

New Member
Nov 20, 2004
234
0
0
Overland Park, KS
Oct 25, 2005
#4
  • Oct 25, 2005
  • #4
I am running a 90 shot wet, and pulled 5 degrees out of the entire rpm range, working good so far.
 
R

Red2000GT

Founding Member
Sep 10, 2000
2,450
0
46
Regina,Sask.Canada
Oct 26, 2005
#5
  • Oct 26, 2005
  • #5
I made SEVERAL runs on a 150 wet shot with no timing adjustment,just premium gas and a bottle of octane booster in the tank. I had no problems until I accidently let the bottle pressure get too high and burnt a valve. I think you should run 2-step colder plugs,and get yourself a rpm window switch. Set the shut off rpm to about 58-5900,well below the factory rev limiter(it cuts off fuel to limit rpm). Also a fuel pressure guage to monitor what happens during a full 1/4 mile run. You may have a weak or bad fuel pump and when the pressure drops to much you're going to run WAY too lean,burn plugs and get backfires.
For those that automaticaly say you can't safely run a 150 shot-WRONG. I personally have done it(for a period of 2 years) & would see no problem with anyone else,AS LONG AS YOU DO THINGS BY THE BOOK!!!! If you want to play around then don't run any bigger than a 100. 150 is not to much for the engine,trans or car to handle but it leaves less room for error. You must monitor your fuel pressure,your bottle pressure,run good gas with octane booster,run 2 step colder plugs,and have a rpm window switch/fuel pressure cutoff switch for safety.
 
S

Smokeurhonda

New Member
May 1, 2003
457
0
0
Maryland
Oct 26, 2005
#6
  • Oct 26, 2005
  • #6
Red2000GT said:
I made SEVERAL runs on a 150 wet shot with no timing adjustment,just premium gas and a bottle of octane booster in the tank. I had no problems until I accidently let the bottle pressure get too high and burnt a valve. I think you should run 2-step colder plugs,and get yourself a rpm window switch. Set the shut off rpm to about 58-5900,well below the factory rev limiter(it cuts off fuel to limit rpm). Also a fuel pressure guage to monitor what happens during a full 1/4 mile run. You may have a weak or bad fuel pump and when the pressure drops to much you're going to run WAY too lean,burn plugs and get backfires.
For those that automaticaly say you can't safely run a 150 shot-WRONG. I personally have done it(for a period of 2 years) & would see no problem with anyone else,AS LONG AS YOU DO THINGS BY THE BOOK!!!! If you want to play around then don't run any bigger than a 100. 150 is not to much for the engine,trans or car to handle but it leaves less room for error. You must monitor your fuel pressure,your bottle pressure,run good gas with octane booster,run 2 step colder plugs,and have a rpm window switch/fuel pressure cutoff switch for safety.
Click to expand...

 
9

97gtblue

New Member
Apr 11, 2005
283
0
0
pensacola,florida
Oct 26, 2005
#7
  • Oct 26, 2005
  • #7
alright i just put the jets for a 100 shot back on...how much is that window switch run??im thinking about calling the local dyno and putting my car on it to make sure im not running lean

ive had the 100 on it before for about 12 bottles,and had no problems..

so do yall think it would be ok with a dyno tune and some octane booster on the 100 shot
 
S

Smokeurhonda

New Member
May 1, 2003
457
0
0
Maryland
Oct 26, 2005
#8
  • Oct 26, 2005
  • #8
100 shot should be fine with a tune
 
S

Smokeurhonda

New Member
May 1, 2003
457
0
0
Maryland
Oct 26, 2005
#9
  • Oct 26, 2005
  • #9
You should be fine with 100 shot and a dyno tune
 

RandyStinchcomb

New Member
May 25, 2005
1,159
3
0
Randallstown, Md
Oct 26, 2005
#10
  • Oct 26, 2005
  • #10
my opinion, your done. once you've melted plugs, knock off a cam follower, your going to have some internal damage. dont do it.
 
S

Smokeurhonda

New Member
May 1, 2003
457
0
0
Maryland
Oct 27, 2005
#11
  • Oct 27, 2005
  • #11
Eh **** it....GET R DONE!
 
T

thomas91169

I'd donkey punch my sister.
Aug 19, 2005
0
0
0
Modesto, CA
Oct 27, 2005
#12
  • Oct 27, 2005
  • #12
first off, octane booster does absolutely nothing. do some research, and you will find you would be lucky to raise your octane rating by .1 instead of 1 like they advertise. fools gold it is.

second, 150 shot is way too high on stock tune and no wideband o2 unit. if youre going to run nitrous, youre number one priority is knowing your a/f ratio at any given time.

third, definately a window switch. you dont want to bounce of mr rev limiter, it cuts fuel which means you run on straight nitrous which means you predetonate and things heat up and melt. such as spark plugs and pistons.

fourth, as said above, it could be more damage than expected. ive seen melted pistons before melted plugs, and those were 500hp dsm's. bad tuning and running lean will do that.

id take the heads off and check to make sure your pistons are still there. if theyre there, a new head gasket and arp hardware while youre at it, might sound overkill but spending a little bit now is worth more than spending more later. if you knew that, we wouldnt be having this thread. then when you get it running, dont go past 100 shot without some dyno time, 100 octane or better gas(if i can get 100 octane for 4.50 in cali, you should have no problem), and a bottle heater and window switch(set a few hundred rpm's lower than redline).
 
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