Solid Lifters, Springs, and Double Roller Rockers

[99svtvert]

I have finished the install on my FR500 HCI 99 Cobra. Includes new springs and SFI Balancer. Engine acutally quieter than stock hydraulic lifters (adjusters) (so far). Exhaust is noticibaly louder (more crackle and snap).
Put 250 miles on it; then Dyno Test.

Initial Dyno; no re-tune;

I will Post pictures and dyno charts later in the week.

Initial Dyno:

Max RWHP (DynoJet) @ 8150 RPM 433.1 RWHP (+24 RWHP change) - still making power with FR500 HCI. Near constant safe A/FR.

Max RWHP (DynoJet) @ 7500 RPM 422.2 RWHP (+13 RWHP change)

No real torque changes (+5 RWTQ) Max.


Do you think a new dyno tune will raise these numbers at all ?

 

[Quadcammer]

I wouldn't think so. The tune (in my opinion) should be done with the expectation of properly controlled and timed valve events.

Btw, if solid lifters are quieter than your hydraulics, something was up.

 

[99svtvert]

There is the not ticking like I am used to (maybe they are all ticking at the same time) instead just 1, 2 or 3 lifters that are not working correctly.

Quadcammer, I think you are right (drove it again tonight) it may be that the combined ticking of 32 lifters is perceived as quieter but I now think the engine noise is louder. So does a friend.

BTW, The engine (through exhaust) does roar much more.

I am going to wait a few weeks and do valve lash adjustments then.

 

[REX-RACER]

Initial Dyno:

Max RWHP (DynoJet) @ 8150 RPM 433.1 RWHP (+24 RWHP change) - still making power with FR500 HCI. Near constant safe A/FR.

Max RWHP (DynoJet) @ 7500 RPM 422.2 RWHP (+13 RWHP change)

No real torque changes (+5 RWTQ) Max.

You really ran your engine up to 8150 rpms?! Damn!

Is this still stock displacement? Anything done to the intake?

 

[coolguy10786]

I wouldn't think so. The tune (in my opinion) should be done with the expectation of properly controlled and timed valve events.

I agree, most of that power is probably coming from the roller rockers. If the valve lash is different, i can see where a tune mayhelp, but i don't think it would be worth it.

The other thing is that when it was tuned, what rpm did he take it to? If it wasn't taken to 8000, then there maybe some power to be gained there, but i couldn't tell you for sure.

 

[03Steve]

What is your commanded air/fuel and average engine timing under WOT?