if you pm me your email i will send you the tune.
i have never hoped more for a broken fuel pump than right now. :-)
if you pm me your email i will send you the tune.
i have never hoped more for a broken fuel pump than right now. :-)
fuel pump not broken.....the bolts that hold it down sheared off. how could this happen?
I bet that lash cap was causing the pump plunger to bottom out. You have an upgraded cam lobe?Originally Posted by Higgs Boson
Jaime
Oh wow. This is not the stock pump, correct?
2001 Z06 : 856/830 : Built LQ9 403ci : D1SC 17psi : Self-built , self-tuned.
stock cam lobe, LT4 pump, lash cap
I called Texas Speed to make sure I had a stock fuel lobe, which I do, and they told me the LT4 pump has a shorter stroke than the LT1 pump.
My LT4 pump with a lash cap and stock fuel lobe put enough upward pressure on the mounting bolts to shear them off and allow the pump to bleed off pressure under boost.
I would not recommend the lash cap on an LT4 pump. Maybe it's fine on a stock LT1 pump, but don't risk it on a Z06 pump.
That's the 4th time in 2 months I've heard of someone breaking something due to bad info from Texas Speed. They need to get it together or at least learn it's ok to say "We don't know".
2001 Z06 : 856/830 : Built LQ9 403ci : D1SC 17psi : Self-built , self-tuned.
i am saying they gave me good info. they aren't the ones who told me to put a lash cap on the LT4, they told me not to (this morning).
i bought the cam from them like a year ago, i added the LT4 pump and lash cap a month ago. It's my fault (classic, I read on the internet that other people have done it so I did it too).
Ok , well regardless my statement stands due to what I've already seen. Anyways , I'm glad you found the problem
2001 Z06 : 856/830 : Built LQ9 403ci : D1SC 17psi : Self-built , self-tuned.
for sure, thanks. hopefully I have enough fuel still!
Even though you had a "stock lobe" it was still an aftermarket cam so you risk tolerance stacking as well. Sounds like it's just not worth the risk. 4 out of 5 guys may get away with it. I'm usually the 5th guy.
Jaime
It gets even better. I guess when the pump pushed up and broke the bolts the lash cap fell off. It is somewhere in the oiling system....
Ugh.
Jaime
Can you run a camera scope into the pump lifter hole and have a look around? Can even tape a magnet to the camera and grab that sucker if you see it
2001 Z06 : 856/830 : Built LQ9 403ci : D1SC 17psi : Self-built , self-tuned.
It's not the first lash cap that has gone down the black hole.....a guy on Corvette Forum dropped his and spent a week or two looking with no result.....I gave it an hour, putting it back together, hopefully it's just in a pan baffle. Who knows how long it's been or when it came off....
Tuned on it today a little bit.....blew the intake tube off the throttle body at 5600 RPMs around 8psi so I need to rethink my nut tightening abilities, but HPFP situation is good, losing low pressure on E27, so going to have to wait for a full blast E85 pull until I get the secondary pump on it.
At 5600 it was flowing 81.5 lb/min though, which seems pretty cool.
Great news Higgs....
ECS uses Tbilisi clamps correct!?? Tighten her down ha
At 5600 probably making 750rwhp lol
Tbolt I mean
I'm assuming just lt4 pump no lash cap?
Good news. My car kept blowing the intake off regardless of clamp tightness until I took the filter off the blow-off valve. Then it miraculously stopped.
2001 Z06 : 856/830 : Built LQ9 403ci : D1SC 17psi : Self-built , self-tuned.
LT4 pump, no lash cap. I am running a Tial BOV, I don't think there is a filter....?
Looking forward to getting that extra lift pump from Joe at CPR in AZ.....
Going to pulley down, rev up, go full E85....
Any guesses what it will make all in if 5600 RPM = 8 psi and 81.5 lb/min?
6800 RPM, 12 psi, and full E85........? Think I can get 1000 at the crank?
Vengeance made 1000whp on stock bottom, ported heads, cam, meth, nitrous , non-z c7 . Don't know what fuel though. If you're at 12psi redline you're probably running the 3.7" pulley? The 3.4" pulley should be good for 16psi and 950+whp , depending on CR.
There were 2 main things that stuck with me after tuning the last C7 , failing the MAF limited TPS to 60% , couldn't figure it out. Turned MAF back on , back to 84%. And advancing the intake cam WOT base angle table gained a ton of power and reduced boost.
2001 Z06 : 856/830 : Built LQ9 403ci : D1SC 17psi : Self-built , self-tuned.
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