Marble_Sharp

iTrader: (5)

I am looking for advice from someone who has experience with similar set-ups to mine. I am getting valve float over 6,000 rpms. Below is my current set-up. Need recommendations on good springs that people have had proven success with on similar set-ups. This set-up is currently N/A. May add a 200 shot of nitrous down the road.

heads - PI/Mast Big Bore LS7 heads
http://www.mastmotorsports.com/2010/... - Bare&id=359

intake valves - from Mast Motorsports
http://www.mastmotorsports.com/2010/...=Valves&id=169

I think these are the exhaust valves, I don't believe they are hollow stems.
http://www.mastmotorsports.com/2010/...=Valves&id=161

Lifters = morel link bar limited travel

Rockers - T&D adjustable shaft rockers - 1.8

Cam - 243 247 LSL 112+4 .661 lift

TurboBuick6

iTrader: (2)

What springs are in it now?

Marble_Sharp

iTrader: (5)

These ones from MAST -

http://www.mastmotorsports.com/2010/...Springs&id=183

fuel

iTrader: (13)

hydro or solid roller

Marble_Sharp

iTrader: (5)

Hydraulic - Morel limited travel

fuel

iTrader: (13)

im only guessing, maybe the lifters are calapsing

3pedals

iTrader: (3)

NEED to know what springs MAST installed on your heads. springs are VERY important.

SweetS10V8

iTrader: (4)

Lighter valvetrain.

Need to know what springs you have and how they are setup.

Rockers are heavy pigs, swap to oem rockers and try it out.

Marble_Sharp

iTrader: (5)

All I know about the springs is what I posted in post #3.

I agree springs are important and I am certain they are the problem. That is why I am looking for input on what springs others have used successfully with similar set-ups.

Gray86hatch

iTrader: (83)

what are the installed specs on the spings? What PR. How much preload on the lifter.

Tim

Sdunn

What engine do you have these heads on? What intake and fuel set up are you running?

ramairroughneck

iTrader: (35)

Sorry to get off topic but how much compression are you running? E85? I am really impressed with the rwhp given the problem. Thats an awesome number to put down by only 6100 rpms. Most guys cant get that even with larger cams. Good luck and keep us informed.

Marble_Sharp

iTrader: (5)

Sorry, but I don't know the answer to these questions. This stuff was done by a shop.

Marble_Sharp

iTrader: (5)

LS7 engine, FAST 102 intake, NW 102 Throttle body, 8.1L bucket.

Marble_Sharp

iTrader: (5)

I think the compression is around 11.5.

Pump gas - 93 octane.

It is a M6 with 4.10 gears.

cam

iTrader: (9)

I have no "proof" per se but seeing as there are simply not that many spring manufacturers out there the MAST springs appear mighty similar to PAC springs which are very good quality. Considering this;

Im agreeing with above. Ditch those heavy *** rocker arms for some stockers and see how it goes. Its a cheap, fast, and simple thing to start with. If that doesnt do it then lighter valvetrain is probably your answer but still... Lots of guys revving the **** to 7K RPM on solid valves without issues so?

fossil

iTrader: (1)

I agree with Cam. I had a 6.0 with aftermarket heads, springs, retainers, and rocker arms, and at 6,200 rpms full throttle at track would will feel like a engine miss or skip, real bad on 2-3 shift. Come to find out was valve float, replaced rocker arms with factory rockers and never had problem again.

Gray86hatch

iTrader: (83)

I would stuggest checking the springs to see what the pressures are first. 150-400 at least is needed.

How was the tune I have seen that cause issues that look like valvetrain issues.

Tim

Marble_Sharp

iTrader: (5)

Thanks for all the input.

What I am really looking for is someone with experience with similar set-ups to tell me / sell me some proven springs.

TurboBuick6

iTrader: (2)

Those springs should be fine, I know who's they are. How close to coil bind did you engine builder set em to?

What type of retainer are you using?