[ap72]

Originally Posted by spinn

Summit makes a number of headers, coatings , etc. Clearing up, that these are the basic $89 buck headers for a 85 gm truck.

The inside retainer dia must be the same from votx retainer to v6 retainer, or work with the v6 locks. There might be an extra retainer somewhere, if found the measurements will be posted. The seal part number is not on the reciept, but will post that when it comes to light.

For posterity my crap measurements are saved. My spring measurements could not be repeated every time. My tools are junk.

free length 1.94"
Installed at 1.8 they were about 95lb seat and open 275 at .500
Installed at 1.6 it was 125 and 305

To clear up , the safe running lift is not 1/2" , the seal is going to touch. Lifts of .450-.460" cleared on votex heads with seals.

So your installed height with the 8mm locks and retainers was 1.600" Or is that 11/32 locks and 8mm retainers? Comp makes the proper retainer to run those beehive springs on a 11/32 valve stem with 11/32 locks, its like $65 a set for the retainers though. the tool to cut the guides down for better seals and reduced height is only $50, I bought one and have used it several times. A tap set can be picked up at Harbor Freight for like $20 (cheap but it works). Then you only have to buy shoulderless screw in studs and a Z28 spring kit to run a mild flat tappet cam with no worries. I've done that routine on a BUNCH of heads (usually i use better springs though) and it works great for a mild street engine.

[cobalt327]

Originally Posted by spinn

Installed at 1.8 they were about 95lb seat and open 275 at .500
Installed at 1.6 it was 125 and 305

This would be a 360 lb/in rate.

This is very close to the Comp Cams spring p/n 26981. Seat 110# @1.7", open 292# @ 1.175 (0.525").

My question is why would GM this spring on the 3100? Maybe it's because of the redline of this engine. Or a tall installed height... Anyone know what the installed height is on the 3100? Or the redline? I know the redline of the '09 Impala 3.5L is 6400 and will rev higher.

[ap72]

Originally Posted by cobalt327

This would be a 360 lb/in rate.

This is very close to the Comp Cams spring p/n 26981. Seat 110# @1.7", open 292# @ 1.175 (0.525").

My question is why would GM this spring on the 3100? Maybe it's because of the redline of this engine. Or a tall installed height... Anyone know what the installed height is on the 3100? Or the redline? I know the redline of the '09 Impala 3.5L is 6400 and will rev higher.

I'm pretty sure its 1.800".

[spinn]

Run hard, whats that. It is drivin . The vehicle takes my scooters out by my brothers' kids for a blast. That is about 100 miles round trip. It does burnouts and the wide open downshifts that kick nice. Using a phone device with GPS an app for testng performance, claimed sub 16 quarter at 88 mph. To take it to a track is big money, and all the test and tune days are gone. Byron, Rt 66 ,and great lakes are busy, and have no time for my messing around. For the admit you might get 2-3 runs. This has been together many months.

The keeper/locks are stock from the vortec 906 heads. If someone works at a yard or parts depot, measure the v6 series 2 valves, that will tell if it is really 8mm or 11/32 .

GM advertised spring rate of 330-365lb/in depending on the .

Is sinking the spring seat the good way?

Did not mean to steal the thread.

[ap72]

Originally Posted by spinn

Is sinking the spring seat the good way?

Your spring seat remains unchanged, unless you want to sink it slightly. You only cut the guide in height and in OD to prevent retainer to seal clearance, AND allow the use of .530 valve seals, which come in MANY varieties for dirt cheap.