Hellion 6266 Dyno, Valve FLOAT? Spark?

[tsloms]

I can do that, but its not blowing out spark..

As I said previously as well Lund also told me it was springs for sure and after replacing them it made no difference.

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[markmurfie]

Probably not a good idea to try to run 15psi+ on a waste gate with a 6-7# spring in it. That's where too much back pressure will matter.

Back pressure over coming the exhaust valve spring strength by pressing on the back of the valve is far fetched to me. 35psi is not a lot compared to a valve spring, and thats being generous with high back pressure.
The fact that in all the dyno graphs with this issue the RPM's still climb, and the issue goes away at a higher RPM. With valve float if you don't get interference, it is like hitting a rev limiter. Path of least resistance in mind, everything points to a waste gate being pulled open and loss of boost issue before exhaust valve being pulled open causing valve float.

 

[kcc0521]

As I said previously as well Lund also told me it was springs for sure and after replacing them it made no difference.

Did you ever resolve the issue?

 

[tsloms]

Did you ever resolve the issue?

For me even with 12 psi I was breaking up badly. I replaced the springs which did nothing at that boost level but did allow me to crank up the boost later. I needed springs at some point anyways so it’s not a big deal.

The fix for me was to go from .028” down to .023” gap and she ran like a champ.

 

[Dennisn]

Are you implying Lund tuners are panicing while they're reading customer's logs and don't know what they're looking at?

Because the OP said his tuner specifically said he noticed the issue in the cam timing. It's not like amateurs are reading through their logs and immediately panicking and shouting valve float.

Here ya go. Mod list in sig. 15, 14, and 12 psi. Stock springs and motor. Lund told me the dip at the top of the power band on 14-15 psi may be valve float but they didn't say for sure.

This is exactly what my graphs looked like when my valves were floating. Changed springs and nothing else and everything was fine. Pulled all the way to the top with no dips.

 

[Phils15GT]

How difficult/expensive is it to change the springs?

 

[Notagain]

Are you implying Lund tuners are panicing while they're reading customer's logs and don't know what they're looking at?

Because the OP said his tuner specifically said he noticed the issue in the cam timing. It's not like amateurs are reading through their logs and immediately panicking and shouting valve float.

Here ya go. Mod list in sig. 15, 14, and 12 psi. Stock springs and motor. Lund told me the dip at the top of the power band on 14-15 psi may be valve float but they didn't say for sure.

Some people = Owners not the tuners.........

 

[Ponderthis]

Probably not a good idea to try to run 15psi+ on a waste gate with a 6-7# spring in it. That's where too much back pressure will matter.

Back pressure over coming the exhaust valve spring strength by pressing on the back of the valve is far fetched to me. 35psi is not a lot compared to a valve spring, and thats being generous with high back pressure.
The fact that in all the dyno graphs with this issue the RPM's still climb, and the issue goes away at a higher RPM. With valve float if you don't get interference, it is like hitting a rev limiter. Path of least resistance in mind, everything points to a waste gate being pulled open and loss of boost issue before exhaust valve being pulled open causing valve float.

I have 10.5psi springs.. I like to be able to turn my car down with the GFB boost control on the street.

 

[Slamdcoop0428]

I know this kit makes big power on built motors with upgraded springs.

I want to see Dyno graphs on stock motors with stock springs at 14+ psi.

I ran 15 psi with my stock motor and hellion kit and ran 8.9 at 153 still holding the stock gen 2 record as far as I know. Now I have a built motor with valve springs and 18psi and make around 1000whp.

 

[HELLION TURBO]

I ran 15 psi with my stock motor and hellion kit and ran 8.9 at 153 still holding the stock gen 2 record as far as I know. Now I have a built motor with valve springs and 18psi and make around 1000whp.

EXACTLY!!!!

The base system with no mods will run its tail off!!!! It will outrun anything on the road, no springs or mods needed...the power of turbos!

 

[MadCow]

I ran 15 psi with my stock motor and hellion kit and ran 8.9 at 153 still holding the stock gen 2 record as far as I know. Now I have a built motor with valve springs and 18psi and make around 1000whp.

Did your stock motor break or did you just decide to put in a built motor?

 

[Slamdcoop0428]

Did your stock motor break or did you just decide to put in a built motor?

Didn’t blow up. Just stretched a stock head bolt. Never over heated. Just when the car was cold it would trickle coolant in the number 7 cylinder. Still ran perfect lol but decided while it’s out might as well build it better. I sold the stock short block.

 

[ahl395]

Didn’t blow up. Just stretched a stock head bolt. Never over heated. Just when the car was cold it would trickle coolant in the number 7 cylinder. Still ran perfect lol but decided while it’s out might as well build it better. I sold the stock short block.

Damn, stretched a head bolt at 15psi? I'm scared now lol I didn't think that would be a problem until higher boost levels. Might be dialing back to 14psi on my car...

 

[Slamdcoop0428]

Damn, stretched a head bolt at 15psi? I'm scared now lol I didn't think that would be a problem until higher boost levels. Might be dialing back to 14psi on my car...

Don’t be scared lol. My stock motor had seen 14-15 psi for 2 years at well over 800whp at the end there I was around 900whp.

 

[tsloms]

I lifted my heads slightly at 17psi with the Whipple previously. Coolant seeped ever so gently from the rear of the heads like the engine was crying under full boost.

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