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I was out at the track this weekend and half way through the second session for the day the car started ticking really bad. Drove back to the pit and pulled the valve covers off. Lots of space between a few of the rockers and pushrods. See the video I can almost fit my pinky finger in between the rocker and valve springs. It was VERY hot at the track 109 F,
It was a fresh rebuild, 2nd track day on the car probably 4 or 5 hours total on the engine since the rebuild. This car is used for drifting so mid - high RPMS sometimes bouncing off the limiter for a bit at 7k
ported 243 heads
MS3 cam 113 LSA
PRC .650 dual valve springs
LS7 Lifters
replaced lifter trays
TSP 7.4 pushrod
BTR trunion bearing upgrade on stock rockers
Fast 102/92
Melling High Volume Oil Pump
Longtube headers to straight pipe exhaust
Pulled the pushrod out and looks like the picture below
Gonna pull the heads off sometime this week and take a look at the lifters, hopefully the cam isnt damaged.
So I guess my current question is what do you think could be the cause for this if it is a lifter failure. Do you think the oil got too hot? I am not currently running an oil cooler but going to install one before I take the car back out. or could the cam / springs / rpms be too much for the ls7 lifters?
Thanks for the help, I will post more info on what I find and pictures once I take the heads off.
The only thing I can say offer is I ran 2 track days with no oil cooler and I saw 315 degree temps after about lap 3 and they stayed there for 20 minutes. This is with my bone stock LT1 with LS7 lifters. The I sent an oil sample to Blackstone and they said my oil didn't break down and was just fine. It was with Rotella T6.
Are you experienced at building drift engines? I am not, I can only imagine
the time and thought process it takes to build an engine and expect it to bounce off of
the limiter like that, time and time again, wake up the next day and do it again.
I wish I had a build room clean enough to where I would be 100% positive that it was
parts, and not my lack of experience in building machines like that. Maybe some day.
It could be a lifter problem, your pushrods are correct for sure? I wouldn't run ls7's if you still want to run a drop in, (lifter tray) id run the morel 5315 if not, get a link bar set up. What lift cam are you running? Idk if valve float would cause something like that meaning maybe not enough spring for your cam or what? Maybe someone more experienced can chime in.
The only thing I can say offer is I ran 2 track days with no oil cooler and I saw 315 degree temps after about lap 3 and they stayed there for 20 minutes. This is with my bone stock LT1 with LS7 lifters. The I sent an oil sample to Blackstone and they said my oil didn't break down and was just fine. It was with Rotella T6.
Steve, if you don't mind would you please post the analysis they sent you,
I am trying to convince the upper brass at my work to consider the use of
this service for some of our fleet warranty issues. Thanks
For starters, the pushrods are too thin. The 5/16" OD pushrods will be like spaghetti at the high RPM. Since you frequent high RPM i suspect you were likely losing control of the valve train and damaging parts. I wouldn't be surprised if the lifters and cam are toast.
Believe the MS3 cam uses XER lobes, not the most favorable for a high RPM motor.
LS7 lifters, don't think they will take the abuse of high RPM with a XER cam and higher spring rates. They weren't designed for that.
For starters, the pushrods are too thin. The 5/16" OD pushrods will be like spaghetti at the high RPM. Since you frequent high RPM i suspect you were likely losing control of the valve train and damaging parts. I wouldn't be surprised if the lifters and cam are toast.
.
Said the internet, without actually doing it?
I ran the typical 5/16" 0.080 pushrods in my heads/cam ls1 back in 2004 and repeated 7200 rpm shifts and 1/4 mile runs. Even with heavy dual springs. Not one issue. Stock ls1 lifters.
I ran the typical 5/16" 0.080 pushrods in my heads/cam ls1 back in 2004 and repeated 7200 rpm shifts and 1/4 mile runs. Even with heavy dual springs. Not one issue. Stock ls1 lifters.
Drifting and drag racing are two different animals. You get to 7200 and shift, he gets to 7200 and hangs out there for a while. Coupled with the possibility that the cam was way too aggressive, his valvetrain was almost certainly out of control. It wasn't a lifter failure, just about any lifter would have failed that environment. It was an engine builder failure.
Another idea, I've read that the Delphi (ebay unmarked) ls7 lifters are a different lifter to the boxed genuine "GM" LS7 lifters. Anyone know how true that is? I haven't bought both to confirm. I always use genuine GM. If so maybe you have the Delphi "LS7" replacement lifters, and not what GM actually puts in their LS7 engines from the factory?
From: Halfway back on the Highway to Hell...again!
Any lifters produced between 99-05 were from one manufacturer and were garbage. That's why GM changed manufacturers and when they did, the new part number corresponded with the lifters that went in the LS7, thus, LS7 lifters. but no different than the lifters used in any other GM engine now.
The original "Delphi" lifters were used from 87-98. These were the best you could get OEM. They were American made and if there was a failure, it was very rare that the lifter itself gave out under moderate lifts and durations. It was usually due to another component that took it out or way too much lift where a solid roller should have been implemented.
So the term "LS7" lifter is nothing different than what I have on the shelf going in as a replacement for any LS engine needing lifters.
I would say the MS3 camshaft is the root of this problem. The lobes are too aggressive even on the new "softer" version of the cam for prolonged high rpm use.
It doesn't help that you used "LS7" lifters and cheap pushrods though.
In the future if you want the engine to live a Cam Motion, Brian Tooley, or LXL lobed Comp cam will definitely improve valvetrain stability. Couple that with 11/32" Manton or Trend pushrods and Morel link bar lifters and you should not have this issue again. Oh and don't forget a timing chain damper as well.
The original "Delphi" lifters were used from 87-98. These were the best you could get OEM.
On my first cam I ran the old "Caddy racing" lifters and they worked great.
On the next cam I pulled a set out of a Vortec 350 that had a couple hundred miles (a nut went through the engine and busted a piston so the engine was just sitting around) and they worked excellent.
On the last hydraulic I used "ls7" lifters and the car would often make a lot of noise after a 1/4 mile pass. Enough I wouldn't run them or recommend them anymore.
I've gone solid roller now but any future hyrdaulics will be at least a Morel drop in or better. I have no faith in the ls7 lifters anymore. Not that I think they are all bad, I just have terrible luck with getting the flukes.
Any lifters produced between 99-05 were from one manufacturer and were garbage. That's why GM changed manufacturers and when they did, the new part number corresponded with the lifters that went in the LS7, thus, LS7 lifters. but no different than the lifters used in any other GM engine now.
The original "Delphi" lifters were used from 87-98. These were the best you could get OEM. They were American made and if there was a failure, it was very rare that the lifter itself gave out under moderate lifts and durations. It was usually due to another component that took it out or way too much lift where a solid roller should have been implemented.
So the term "LS7" lifter is nothing different than what I have on the shelf going in as a replacement for any LS engine needing lifters.
That explains a lot. Also the reason my early ls1 lifters lasted 70,000 miles with over 500fwhp and repeated 7200 rpm shifts and lost count how many WOT runs and racing.. and the day I sold the car, still had the original lifters in it and they were quiet as a mouse.
My current LS1 I put in my lt1 fbody (in sig) had a full rebuild before I bought it, not by me, and the lifter sound scares me. I hope the new genuine AC DELCO packaged GM lifters I fit soon are a proper lifter, as good as my early heads/cam ls1 had in it all those years ago.
I would say the MS3 camshaft is the root of this problem. The lobes are too aggressive even on the new "softer" version of the cam for prolonged high rpm use.
It doesn't help that you used "LS7" lifters and cheap pushrods though.
In the future if you want the engine to live a Cam Motion, Brian Tooley, or LXL lobed Comp cam will definitely improve valvetrain stability. Couple that with 11/32" Manton or Trend pushrods and Morel link bar lifters and you should not have this issue again. Oh and don't forget a timing chain damper as well.
Depending on when you bought the MS3 will tell us what lobes were used on the camshaft. If it were purchased in the last year and half chances are it was the TSP designed lobes. Those lobes are quite easy on the valve train while still making great power. For someone to state a Cam Motion or comp is better way for you engine to last longer is just nonsense.(FYI Brian Tooley uses comp or cam motion to grind his cams) To call a 5/16ths pushrod a cheap pushrod because it isn't 11/32 or 3/8 is another nonsense move. There are thousands of people that spin 7K RPM using a 5/16ths pushrod. Each setup may require different items, but not so much in this case. If you are using one of our new camshafts that we grind in house, there isn't a chance that a cam motion or comp grind are better in any way, lobe design included.
More than likely you had a lifter fail. The LS7 or LS7 style lifter from delphi work great in most cases, but do have their fair share of issues. Its not a design issue, it is a seat pressure issue. When you move to a double spring that provides a lot more seat pressure than a stock beehive spring does, it isn't a bad idea to upgrade the lifter to a Johnson, morel or Hylift that are designed to handle the increase in seat pressure. While 99% of people get away with an LS7 lifter there is alway a slight chance of failure especially at that RPM
Dominic
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Once you get the car torn down and find out how much damage you have incurred, give me a call. I would like to help you out with pricing and will personally help you pick out the parts that best fit your driving style.
Dominic
__________________
Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
Once you get the car torn down and find out how much damage you have incurred, give me a call. I would like to help you out with pricing and will personally help you pick out the parts that best fit your driving style.
Dominic
Will do, I plan on taking it apart this weekend.
I purchased the cam package March 2015 so seems it may be the new version
Yes, the "internet" did do it, that's why the internet switched to a stiffer pushrod and tested the high RPM before and after. That's why the internet found a big difference in upper RPM valve train stability.
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ls7 lifter failure? 
