#7 Ringlands bad?
08-07-2005, 11:48 AM
#1
#7 Ringlands bad? I've been out of the LS1 game for a while and now am just getting back in.. I have noticed alot about the #7 piston ringlands going bad on this forum.. Funny thing is, my first TTi kit cracked my #7 ringlands.. Is this a common problem, why only #7?
08-07-2005, 12:17 PM
#2
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Well it is usually the #7 or #8. The reason is that they are at the back of the stock intake manifold. So basically what happens is ALOT more air is forced into those then say the #1 and #2 ports. So the car may be readin that it has a safe AFR but what is happening is that the rich cylinders, #1 #2, are balancing out the AFFR with the lean cylinders, #7 #8. So ya end up runnin a lean AFR in those 2 and overheating or detonating. GL man.
John
John
08-07-2005, 11:06 PM
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A carb like intake with a elbow will counter this. Not cheap but alot better then runnin lean on a cylinder. Some people change the injector that is there and pout one that is a little bigger. GL
John
John
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08-08-2005, 07:05 AM
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Originally Posted by 99SS-T
Well it is usually the #7 or #8. The reason is that they are at the back of the stock intake manifold. So basically what happens is ALOT more air is forced into those then say the #1 and #2 ports. So the car may be readin that it has a safe AFR but what is happening is that the rich cylinders, #1 #2, are balancing out the AFFR with the lean cylinders, #7 #8. So ya end up runnin a lean AFR in those 2 and overheating or detonating. GL man.
John
John
Sounds to me like these two cylinders might be getting starved for fuel do to insufficiant fuel supply within the rails... dual fed rails with a good fuel system will go a loooooong way.
BTW, forged pistons don't fix the problem... just mask it.
08-08-2005, 09:35 AM
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Changing the piston material does nothing to change the air and fuel distribution. Forged pistons with certainly be more robust and therefore not break as easy, but the problem is still not addressed w/o any other changes...
IMO the reason # 7 always goes is because it's the last injector on the factory fuel rails to be fed (which are plumbed in series from the factory) so it's the first to starve for fuel which causes that cylinder to go lean. Going to a dual feed rail system and making sure there's plenty of fuel pressure solves the problem IMO. Changing the intake doesn't solve the problem either since this fuel starvation problem still exists.
IMO the reason # 7 always goes is because it's the last injector on the factory fuel rails to be fed (which are plumbed in series from the factory) so it's the first to starve for fuel which causes that cylinder to go lean. Going to a dual feed rail system and making sure there's plenty of fuel pressure solves the problem IMO. Changing the intake doesn't solve the problem either since this fuel starvation problem still exists.
08-08-2005, 11:29 AM
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How are you going to do, and measure, that???
The problem IMO is there's no more fuel at the end of the rail since it flows in series... you can't add any more fuel if there's not any to be added!
The problem IMO is there's no more fuel at the end of the rail since it flows in series... you can't add any more fuel if there's not any to be added!
08-08-2005, 12:50 PM
#13
Sorry if this seems ignorant, I'm just a newbie to the whole FI scene, but wouldn't a FMU help out a little by blocking or restricting the return fuel supply therefore letting some fuel stay in the end of the rail to be availabe for the #7 & 8 injectors?
08-08-2005, 12:53 PM
#14
Originally Posted by ChevyChad
Sorry if this seems ignorant, I'm just a newbie to the whole FI scene, but wouldn't a FMU help out a little by blocking or restricting the return fuel supply therefore letting some fuel stay in the end of the rail to be availabe for the #7 & 8 injectors?
Last edited by Zombie; 08-08-2005 at 01:00 PM.
08-08-2005, 12:53 PM
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I feel it is airflow related to the cylinder and not fuel related.
Using a slightly larger injector in those two holes would help. It would be nice to control the pulsewidth for each individual cylinder with LS1 edit/HPtuners but you can't.
Using a slightly larger injector in those two holes would help. It would be nice to control the pulsewidth for each individual cylinder with LS1 edit/HPtuners but you can't.
08-08-2005, 01:59 PM
#16
Originally Posted by CHRISPY
I feel it is airflow related to the cylinder and not fuel related.
Using a slightly larger injector in those two holes would help. It would be nice to control the pulsewidth for each individual cylinder with LS1 edit/HPtuners but you can't.
Using a slightly larger injector in those two holes would help. It would be nice to control the pulsewidth for each individual cylinder with LS1 edit/HPtuners but you can't.
OHHHHH so then basically it'd be a better idea just to double up on the fuel rails then, then how come the street procharger kits just sell the kit with....ooh they do sell it with the injectors and a hand held programer dont they?
