Poor engine dyno results after Cam/Lifters/Springs/Trunions?
#24
TECH Fanatic
Thread Starter
The problem isn't the power, the problem is that it only gained 18 HP going from a stock cam to an aftermarket cam, when we typically see 40+ HP with cam changes of that size.
#25
LS1Tech Sponsor
Join Date: Jan 2008
Location: Ohio, Georgia, Nevada, Texas
Posts: 2,024
Received 1,231 Likes
on
663 Posts
This is with the TFS-2500286 duals? We'd agree the lifters are suspect for the curve to look like that if you have the 2500286 springs or even a good TFS-16918 beehive. Our customers have been very happy with the SUM-HTLSKIT lifters. No failures and 53 reviews with a near perfect 5 star rating from everyone that's purchased them. $153.99.
#26
TECH Fanatic
Thread Starter
This is with the TFS-2500286 duals? We'd agree the lifters are suspect for the curve to look like that if you have the 2500286 springs or even a good TFS-16918 beehive. Our customers have been very happy with the SUM-HTLSKIT lifters. No failures and 53 reviews with a near perfect 5 star rating from everyone that's purchased them. $153.99.
Also, the TFS-16918 springs were the only TFS spring in the "recommended parts" section with this cam, the duals were nowhere to be found at the time.
The Crane lifters were swapped to the Summit lifter kit and the valvetrain is noticeably quieter now, but it didn't gain or lose anything.
#27
LS1Tech Sponsor
Join Date: Jan 2008
Location: Ohio, Georgia, Nevada, Texas
Posts: 2,024
Received 1,231 Likes
on
663 Posts
He either purchased the Cam/spring combo kit, SUM-8715-1 that comes with the TFS-16918, or purchased the cam/springs separate, but it does have the TFS-16918 beehive.
Also, the TFS-16918 springs were the only TFS spring in the "recommended parts" section with this cam, the duals were nowhere to be found at the time.
The Crane lifters were swapped to the Summit lifter kit and the valvetrain is noticeably quieter now, but it didn't gain or lose anything.
Also, the TFS-16918 springs were the only TFS spring in the "recommended parts" section with this cam, the duals were nowhere to be found at the time.
The Crane lifters were swapped to the Summit lifter kit and the valvetrain is noticeably quieter now, but it didn't gain or lose anything.
#28
TECH Fanatic
Thread Starter
Thank you for the quick response. At first glance, the 410 and 380 numbers would be "ok" and representative of something with a heavier driveline. The thing that's wrong though is we'd expect to see a much bigger difference over a LS2 cam. 392 out of a LS2 cam in a 5.3 is remarkably strong. More importantly, we would expect way more torque from 3000 on up over the LS2 cam rather than catch up at 5700. Did you see anything strange in terms of KPA at WOT at the end of the pull?...not that it would have an effect on the torque though. Cam installed dot to dot with factory gears?
392 out of the LS2 cam was exactly what I expected having done so many other 5.3s before. This was with 26* of timing, tapering up to 29* after peak torque.
It had only been making about 380 HP before the additional timing taper at the top.
It made 398 on E85 on its first pull while we were still dialing in fuel and hadn't added any timing when the drain plug came out and the engine locked up.
Cam/Springs/Lifters/Trunions/head gaskets are the changes other than new bearings and rings.
AFR is a solid 12.5:1, timing at 27* and it doesn't seem to pick up anything beyond that.
Summit Cam/Lifters/Springs. BTR V2 Trunions, LS9 head gaskets. Fresh TR6 plugs.
170-180 cranking compression on every cylinder. The previous 160 wasn't accurate.
Factory timing components, Ghost cam installed dot to dot.
#29
LS1Tech Sponsor
Join Date: Jan 2008
Location: Ohio, Georgia, Nevada, Texas
Posts: 2,024
Received 1,231 Likes
on
663 Posts
Its a flat top gen 4 5.3 with 243 heads and an LS6 intake, controlled by a Holley Terminator X on a Superflow engine dyno.
392 out of the LS2 cam was exactly what I expected having done so many other 5.3s before. This was with 26* of timing, tapering up to 29* after peak torque.
It had only been making about 380 HP before the additional timing taper at the top.
It made 398 on E85 on its first pull while we were still dialing in fuel and hadn't added any timing when the drain plug came out and the engine locked up.
Cam/Springs/Lifters/Trunions/head gaskets are the changes other than new bearings and rings.
AFR is a solid 12.5:1, timing at 27* and it doesn't seem to pick up anything beyond that.
Summit Cam/Lifters/Springs. BTR V2 Trunions, LS9 head gaskets. Fresh TR6 plugs.
170-180 cranking compression on every cylinder. The previous 160 wasn't accurate.
Factory timing components, Ghost cam installed dot to dot.
392 out of the LS2 cam was exactly what I expected having done so many other 5.3s before. This was with 26* of timing, tapering up to 29* after peak torque.
It had only been making about 380 HP before the additional timing taper at the top.
It made 398 on E85 on its first pull while we were still dialing in fuel and hadn't added any timing when the drain plug came out and the engine locked up.
Cam/Springs/Lifters/Trunions/head gaskets are the changes other than new bearings and rings.
AFR is a solid 12.5:1, timing at 27* and it doesn't seem to pick up anything beyond that.
Summit Cam/Lifters/Springs. BTR V2 Trunions, LS9 head gaskets. Fresh TR6 plugs.
170-180 cranking compression on every cylinder. The previous 160 wasn't accurate.
Factory timing components, Ghost cam installed dot to dot.
#30
Moderator
iTrader: (4)
Join Date: Jul 2014
Location: My own internal universe
Posts: 10,452
Received 1,851 Likes
on
1,152 Posts
I do agree with Diet Coke observation the graph does not look great at all.
#33
10 Second Club
iTrader: (26)
Maybe some of you don't know who OP is, but he's more than capable and has been on here for years helping others under a different username. He has 1 of the coolest builds on this site. He's not an idiot, just had an odd problem. Everybody take a breath.
Oh,and he just had a gender reveal for his soon to be new born....maybe he's a tad preoccupied.....
Oh,and he just had a gender reveal for his soon to be new born....maybe he's a tad preoccupied.....
Last edited by ddnspider; 02-17-2020 at 08:25 PM.
#34
Maybe some of you don't know who OP is, but he's more than capable and has been on here for years helping others under a different username. He has 1 of the coolest builds on this site. He's not an idiot, just had an odd problem. Everybody take a breath.
Oh,and he just had a gender reveal for his soon to be new born....maybe he's a tad preoccupied.....
Oh,and he just had a gender reveal for his soon to be new born....maybe he's a tad preoccupied.....
The following users liked this post:
LLLosingit (02-18-2020)
#36
#38
If I was op I'd tell you to delete that ****.
The following users liked this post:
Abs (04-09-2024)
The following users liked this post:
LLLosingit (02-18-2020)
#40
TECH Fanatic
Thread Starter
The engine has been bought and paid for by someone else now, and he's honestly not nearly as concerned about the lack of power as we are.
He's getting one of those cheap $260 billet 7875s and its all getting dropped in a C10 that has probably 200 HP now.
When I suggested throwing the LS2 cam back in to help diagnose the issue, I didn't exactly get a favorable response.
FYI, all of the spark plugs looked great. All of the plug wires were new when it was dynoed with the LS2 cam.
The heads were hot tanked and cleaned between rebuilds.
At this point I'm not sure what kind of effort he's going to put into diagnosing, especially if the switch is being made to turbo and likely E85 in the very near future.
I'm going to recommend swapping to dual valve springs and flushing out the fuel system on the dyno to see if theres a noticeable difference.
He's getting one of those cheap $260 billet 7875s and its all getting dropped in a C10 that has probably 200 HP now.
When I suggested throwing the LS2 cam back in to help diagnose the issue, I didn't exactly get a favorable response.
FYI, all of the spark plugs looked great. All of the plug wires were new when it was dynoed with the LS2 cam.
The heads were hot tanked and cleaned between rebuilds.
At this point I'm not sure what kind of effort he's going to put into diagnosing, especially if the switch is being made to turbo and likely E85 in the very near future.
I'm going to recommend swapping to dual valve springs and flushing out the fuel system on the dyno to see if theres a noticeable difference.