Turbo question

SnakeBit!

Active Member
Joined
Mar 6, 2014
Messages
870
Reaction score
114
Location
Florida
friend installed a turbo on his 96 cobra. stock basically but he did the coil on plug conversion on it. car is tuned and runs good. but....it pops and crackles, mainly at idle or at decel. it doesn't change fuel trim, i.e., the ratio stays the same when it happens and it does not miss at all. motor is smooth. car has no mufflers and is straight piped all the way out of the back. we are wondering if the cop conversion could be creating this. the early computer is not set up for cop's and not sure if that could create this noise. ideas?
 
OP
OP
SnakeBit!

SnakeBit!

Active Member
Joined
Mar 6, 2014
Messages
870
Reaction score
114
Location
Florida
sct dyno tuned by reputable, very knowledgeable tuner. he said it was definitely not in the tune.
 

evilcw311

Most Evil Member!
SN95 Supporter
Joined
May 9, 2010
Messages
7,456
Reaction score
2,134
Location
Louisville, KY
Didn’t think the stock Ecu could handle cop. Lots of turbo cars cackle and pop on hard deceleration but shouldn’t be at idle.


Sent from my iPhone using Tapatalk
 

lwarrior1016

Mr. Secondary Timing Chain
Staff
Joined
Sep 22, 2014
Messages
8,536
Reaction score
4,333
Location
South Mississippi
Stock ecu will run cop just fine, if they are wired correctly. Ive never heard of a cop conversion causing it to pop and crackle like that. How did he do the conversion? If he bought a plug and play harness, you could easily un-do the conversion and put a set of coil packs on it to test the theory.
 

evilcw311

Most Evil Member!
SN95 Supporter
Joined
May 9, 2010
Messages
7,456
Reaction score
2,134
Location
Louisville, KY
Is it the ls coils you can’t do with the factory ecm then?? I know it was just being discussed somewhere about the factory not being able to do one or the other but must of misread the details.


Sent from my iPhone using Tapatalk
 

lwarrior1016

Mr. Secondary Timing Chain
Staff
Joined
Sep 22, 2014
Messages
8,536
Reaction score
4,333
Location
South Mississippi
Is it the ls coils you can’t do with the factory ecm then?? I know it was just being discussed somewhere about the factory not being able to do one or the other but must of misread the details.

Sent from my iPhone using Tapatalk

Right. The LS coils have their igniter built in and the stock computer will not fire them. All the LS coil needs to work is 12v, ground, and logic ground for trigger. The stock setup is two wire, 12v and ground, but the computer does all the work.
 

ttocs

Post Whore
Joined
Oct 9, 2009
Messages
32,616
Reaction score
5,652
Location
Evansville Indiana
as they said if you think its the ignition then go back to the stock set up and see. Can you post a vid?
 
OP
OP
SnakeBit!

SnakeBit!

Active Member
Joined
Mar 6, 2014
Messages
870
Reaction score
114
Location
Florida
it is a plug and play harness. I can see if he can get a video of it.
 
OP
OP
SnakeBit!

SnakeBit!

Active Member
Joined
Mar 6, 2014
Messages
870
Reaction score
114
Location
Florida
also, in the meantime, any recommendations if he decides to put mufflers back on it...which are best for the turbo. not talking about sound at this point as that is so subjective, just best performance for a turbo. thanks.
 

Forum statistics

Threads
77,492
Messages
1,503,729
Members
14,964
Latest member
bs.austin.tx

Members online

Top