Project VF II Part II - Giving The LS3 Some Stick!
With running This email address is being protected from spambots. You need JavaScript enabled to view it. as a baseline to start from it was time to start camming Project VFII up. Now in PVF we went through a few grinds to demonstrate what power gains came from each grind showing that to a point it becomes deminishing returns after the intitial bang for the buck. PVF 6.0L went This email address is being protected from spambots. You need JavaScript enabled to view it. with SQP/MAST 4.0 head and cam on E85 full weight. We wanted to see where we could get with SQ57 grind in the LS3. Now SQ57 is as big as we can squeeze into these engines without compromising piston strength with valve reliefs. Something SQP don't do. We didn't want to take the heads off at this point. We used this exact camshaft in Arron's LS3 6.2L Calais V a while ago that saw him go 11.37@118.4 mph. So where would it get the ute? Follow along and enjoy the ride!
Never been apart but here we go...
Time to start swinging spanners.
Now we are cooking...get this OEM piece out.
Lifters held up with magnets...out it comes.
Picture below is one of the most over looked steps in this sort of change out...measuring installed heights. How you going to know what pressures are on the spring if you haven't done the set up steps?? And accurately??
Measured installed height is then set up on the calibrated spring tester to set stop. From this we can now put in the spring and take a reading of it on the seat...
There is is on the seat pressure...160psi. A basic reading that is the starting point ot valve train stability. Over the nose it also taken in the tester at full lift but we aren't giving it all away...
Springs all on...
Lifter preload set and 5/16" .080" wall CrMo pushrods fitted...time for the dyno.
What were the gains? Below shows a graph of PVFII in standard trim against cam only SQ57 trim. It uses the same tyre but with a looser converter. A good solid 60rwhp gain but the impressive thing is how well it carries power out to 7200rpm rev limit. Remember that time on the spring tester? That and many years of cam development yields those sort of results. Power seems low? Naah? Just dynos for you...tuning tools not sales tools. Want to see the gains...we will try the track!
John Drives - WAW 11/4/2018
Getting ot the track with a flat out shop and helping customers with their track attacks has PVFII go to the back but found some time to get it there. Drive to the track and bolt of the 275 radials as per everything with the unopened combo the same. How did it go?
First run out saw some nice gains straight up and identified a couple of areas in the tune where more would come from. 11.17@120.85mph.
A few adjustments...tyre pressures checked...lets go again...
11.122@122.19mph! Cooking without gas! A really exciting place to be trimming up from on the cam only rocket...
Damn...start line is softening and the 60' is down but mph up 11.126@122.49mph. Still honking but no improve in ET.
Naah the track is gone. Missed it for tonight but we will be back. As a summary...with John driving, the best we went unopened was 11.61@117.7 mph. So working from that base line the cam changed picked up 4.9 10ths of a second and 6mph. Run that through a power speed calculator and we see a gain of near 80 weight shifted horspower! Not a back pick up from a cam...Where too next? The jockey...he was worth .14 seconds in the ute unopened. That again would have PVFII in the 10s. 10 second cam only? BRING IT ON!!!
Back to the Track.
24/5/2018.
Again finding track time to get PVFII back down in all the other stuff going on at SQP has been hard but we finally got the chance with Shane being available. Hoosier street radials in the back with a jack and to the track it was for one last hit this season. Tyres on into the burnout pit it headed...the aim? 10 second cam only!
First lap out and it looked decent! Nice improve to 11.04@ 124.18mph. Around we go again.
11.015@125.47mph! Now that is just nasty. That is a tease! So close and it might as well been a mile. Damn drag racing is a nasty mistress...
Ahhhh! 11.03@124.28mph It slowed! Slower in the 60' than previous lap. Lets try the other lane...
Well that was just shit! Car went no where and spun through 1st like a MOFO! Back in the pit I have the jack out and tyres ready to change. Joycey rolls in..."naah. One more. Can't let it tease like that!"
AND THERE IT IS!!! This email address is being protected from spambots. You need JavaScript enabled to view it. MPH! Set a goal and we kicked it. Nothing is more satisfying in drag racing! Back in 2002 we went 11.02@124mph with the VU. The fastest and quickest N/A LS in Australia at the time. I left the 10 as we wanted to hit it hard with NOS and in those days we would never of been allowed back. It is something I have regretted for many years. First 10 n/a was right there and we walked away. But thanks to Shane's call...we didn't miss this time!
So cam only changed out...heads never off. 10 second LS driven to the track...wheels changed and driven home again. Pump BP98 fuel. Loving it!! Where to from here?
We hear people with their we could and we should well...WE DID!!! Any other 10 second cam only LS3s around?
Tune in next year...I have a cam and cylinder head package that will wake this girl up some more. Until then. Have a great Winter and thanks for dropping in and taking the time for a read! Can't wait...can't sleep...