Valve spring life span?

[TR87386]

Been tuning with Alky and slowly raising boost but started having an issue with the car. The car only wants to make 4400 rpm or so. It spools up nice and rips right up to that rpm and then starts to surge and won't shift. Not an issue at lower boost. Trans has not acted up at all and only has 2500 miles on it. When the surging starts the boost drops down to around 15#s. Replaced valve springs 11 years ago but only 8-9000 miles. Could they be junk? They were replace with the ones that Kirban sold at the time. I think they were LT1 springs?? Thought maybe this was ignition related (coil ohmed out perfect) but still running the original ignition module. What do the gurus think? Thanks for any help.

 

[TR87386]

Forgot to mention that the log file is 2nd gear and started to get on the throttle at around 31 seconds into the log. :redface:

 

[TR87386]

In reading up old posts on the alky system I guess that the volt booster can make the alky pump "very agressive" could I be spraying so much alky that I am bogging the motor down? I don't think so as the boost is dropping like a stone when the rpm hits 4300 I will remove the volt booster and see what happens. Currently runnin the gain a 6.

 

[TR87386]

Checked plugs, gapped a little wide @ .032 tightened them up to .029 no change at all.

 

[TR87386]

Update: cranked the boost down to 18# and did a WOT run from 0-70. Just before the 1-2 shift I could just feel it surge but on the 2-3 it surged noticabley. Thought it might be the trans but not so much now. Seems like as the load and RPM increase it gets worse. Wondering if the hot weather has anything to do with it. Don't normally drive it too hard on hot days like I have been.

 

[mikestertwo]

Did you disconnect the voltbooster? I just looked at the log and noticed as soon as the voltbooster kicks in the injector pulse width goes flat even though the engine rpm is increasing. If you didn't disconnect it, do it and see what happens.

 

[Dabigguy]

Just a thought on the valve springs......those springs may not have a lot of miles, but they have been compressed for a very long time and may have lost some of their tension because of that. Springs aren't that expensive... $50

 

[TR87386]

Just a thought on the valve springs......those springs may not have a lot of miles, but they have been compressed for a very long time and may have lost some of their tension because of that. Springs aren't that expensive... $50

I agree, I ordered some last night along with a new module. Not bad to change with the tool so why not right.

 

[TR87386]

Did you disconnect the voltbooster? I just looked at the log and noticed as soon as the voltbooster kicks in the injector pulse width goes flat even though the engine rpm is increasing. If you didn't disconnect it, do it and see what happens.

On that most recent run with low boost no it was still on the car. Need to find the plug that use to go into the alt. where the volt booster is now.