Hi everyone,

I have an LS2 402ci stroker with ls3 top end that I have had running for about a year now. Saturday I went in for another tune to get rid of many driveability issues I was having, and we did a few pulls on the dyno as well.

The hp line was coming up and peaking sharply, then dropping off suddenly, very unnaturally right around 6k rpm every time. Both the tuner and shop owner believe it is valve float, and after watching the rpm gauge during a run I think so as well. I haven't pulled the valve covers to inspect the springs yet, but they think one of the springs is damaged/broken. further more I looked at my graph when the engine only had 500 miles during the first tune and the graph was smooth and natural with no weird peak. Car made 500whp before and 492 yesterday if that helps.

So the question is what springs has everyone had success with recently? My cam is a Pat G spec and he recommended patriot dual gold springs which seemed to be great at the time, but after doing some searching around it looks like they have had several failures and wear out after only a few thousand miles. What springs would be good for my cam?

Cam is 226/234 .598/.612 114+2 with eps/lxl lobes. Using morel lifters, stock ls3 rockers with trunion kit and comp pushrods. And the patriot dual gold kit as well.

The tuner recommended the comp26926ts-kit, and it seems like the Brian Tooley springs are really good as well. I was seeing that I could just by the BTR spring kit and reuse my other patriot stuff, is that true? Is the rest of the patriot kit good quality or should I just chunk it for a new kit all together?

Last question, is it worth it to get the TI retainers vs tool steel retainers for a street car? This motor is only being reved up to 7000 rpm max, usually only 6700 rpm.

Thanks,

Ryan.

 

I'd go BTR .660 Platinums, with a ti retainer. Mr. Tooley himself has said in another thread that the ti retainers should be durable enough for street use.

 

I use Tooley springs and reused my Patriot Gold titanium retainers and Patriot locks.

 

I would go with some nice lightweight beehives/titanium retainers ala PSI 1511s or PAC 1518s.

I see no reason for a big heavy dual when you have such lightweight valves and want to rev the engine.

 

Since I'm using factory ls3 valves and they are larger, are they lighter than the ls2 valves? I know the intake are sodium filled but they are larger, so I figured it would offset the weight advantage. I found thread where they were saying that beehives were not able to control SS valves properly due to the higher weight, so I wasn't looking at the beehives due to that. What cam/springs are you running?

I have seen positive things from BTR, but the patriots were the same way back in 2012 when I put this H/C package together, everyone loved them haha. So I'm just a bit weary. Any issues once you dropped the BTR springs in?

 

I use the lunati spring kit.

One set has 20'000 on them the other set had 4500. With a 250-260 .630 cam

Tim

 

They are larger, but since they are hollow stem they weigh a good bit less than even the much smaller 2" valves found in basic 243/317 heads. No I wouldn't run beehives with huge heavy SS valves, but with those being lighter there's no issues.

I run the PSIs and so far so good, and from what I hear they are one of the best beehives on the market with no known failures.

Sure the BTRs are probably top of the line also, but why waste the benefits of such lightweight valves with heavy dual springs. Take advantage of the valve weight and run a lightweight valvetrain for ultimate RPM stability.

 

Thanks for the info! I didn't know the ls3 valves were that light, I just assumed since they were larger they were heavier. I'm kinda looking at the PSI springs now, but they look to be on backorder. However it may not even be my valve springs! I pulled the covers and my springs don't look like the patriots at all. pictures attached. Anyone know what these springs are? they have TI retainers.

Also I just checked my preload (looked up how to do it) and it looks like only .034 of preload! The wrench only turned 3/4(really a bit less) and what the morel link bar lifters need is .080 for quiet operation. I think my pushrod is 7.350" right now, would I need a .050 longer or shorter pushrod? How do I correctly measure the pushroad?

 

Only one presice way to be sure is to get a lifter preload checker tool. It only costs 20 bucks and you save your self a head ache. I didnt have tool first, but i made my own from an old stock pushrod. When i first measured counting rocker bolt turns, versus measuring it with tool. I end up having 0.01 more preload with using a tool, so thread counting isnt so presice way to measure. If your real measurement is .034 you need longer one.

 

I ordered a checker and will see what it comes up with. Also ordered a random 3/8 pushrod to see if it will fit in my head, anyone know if you can fit straight or tapered 3/8 pushrod in an ls3 head?

As far as springs it looks like I have PAC springs from searching around. So maybe not the springs then?

 

I don't know about 3/8 but 11/32 will fit. Manton does custom lengths and I have 11/32 with .120 wall from them. About $200.

Also, the LS3 valve is light. I have it in my TEA heads... but they are cut down. At 2.04" they are only 83g and stock 2.00" valve is 100g. I believe the LS3 valve is in the low-mid 90g weight at full size.

I still run duals, but a good beehive is not a bad idea. You have controllable lobes on your cam, so you should be okay.

Your valvefloat is likely from the Patriots. How old are they? They tend to lose their spring pressures with age/mileage.

 

I don't have anything to add to the good advice you've already received. I'm just hoping you'll post a pic of the car. Open hood pic.

 

I've ran the PRC .650 springs in my stroker with a cam that has more lift without any issues. Nothing against Brian Tooley as that man has a lot of knowledge & loves to share it, but a buddy had his springs and they didn't meet our expectations. We're always good at checking our springs every 6 months due to the amount of miles we put on our cars. I got almost two years out of my PRC spring kit before needing to replace them. My buddy drove a little over a year & ended up needing to replace his. What we found is they are a very soft spring. This makes it great for never breaking but it lost enough spring pressure that he was floating the valves. It may have just been the hard miles put on them but he still figured they would have lasted longer.

 

Thanks for all the great advice! I'm going to spec out some new pushrods and hope that solves the problem. If not I will get the BTR or comp springs, or maybe a set of beehives if I can find one I'm happy with.

Here's a couple snaps of the RX7.

 

Honestly, fit the BTR .660 platinum's & you won't look back other wise you will be mucking around for longer than you should.