Notices
PCM Diagnostics & Tuning HP Tuners | Diablo

Ls1 LOW mph troubleshoot

 
Old 06-25-2019, 02:42 PM
  #1  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default Ls1 LOW mph troubleshoot

Hey guys so I have a 99 z28 with cam and basic bolt ons. It is a 4l80 car with a 3200 converter. All tuned by a reputable shop made 399 to the back tire. Going to the track, the car would only do 13.2 barely getting 102, car wasn't spinning but only getting a 1.9 60ft probably due to the small converter. But with the extremely low mph, I know something is wrong. So I am gonna do a log tonight to start. What are some things I should check, replace, or look into?
Brendyn G is offline  
Old 06-25-2019, 04:10 PM
  #2  
LS1Tech Sponsor
iTrader: (4)
 
LSX Power Tuning's Avatar
 
Join Date: Mar 2013
Location: Brenham TX
Posts: 2,246
Likes: 0
Received 0 Likes on 0 Posts
Default

Post a log and your tune, without those everyone would just be guessing. Do you have a wideband hooked up to show up in the log?
__________________

Full Service LSX Shop
HP Tuners, EFI Live, SCT, Holley, BS3, FAST XFI
Holley Certified Installer & Tuner
MSD, Brian Tooley, HP Tuners, EFI Live, Holley, Edge, Superchips +100's more

Email, Remote, Mail Order, Dyno, Street & Track Tuning
*WEBPAGE* *FACEBOOK* *ONLINE STORE*

LSX Power Tuning is online now  
Old 06-25-2019, 05:33 PM
  #3  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Unfortunately I do not have a wideband hooked up. I attached a log and the tune
Attached Files
File Type: hpl
log 1.hpl (170.7 KB, 6 views)
File Type: hpt
tune.hpt (220.8 KB, 5 views)
Brendyn G is offline  
Old 06-25-2019, 08:17 PM
  #4  
LS1Tech Sponsor
iTrader: (4)
 
LSX Power Tuning's Avatar
 
Join Date: Mar 2013
Location: Brenham TX
Posts: 2,246
Likes: 0
Received 0 Likes on 0 Posts
Default

Where are you located at? Are you higher up in elevation? Your map sensor seems off at WOT.
__________________

Full Service LSX Shop
HP Tuners, EFI Live, SCT, Holley, BS3, FAST XFI
Holley Certified Installer & Tuner
MSD, Brian Tooley, HP Tuners, EFI Live, Holley, Edge, Superchips +100's more

Email, Remote, Mail Order, Dyno, Street & Track Tuning
*WEBPAGE* *FACEBOOK* *ONLINE STORE*

LSX Power Tuning is online now  
Old 06-25-2019, 09:33 PM
  #5  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Located in Ohio, its about 1100ft. Could I need a new MAF?
Brendyn G is offline  
Old 06-25-2019, 10:28 PM
  #6  
TECH Addict
iTrader: (1)
 
kingtal0n's Avatar
 
Join Date: Nov 2011
Location: florida
Posts: 2,129
Received 5 Likes on 5 Posts
Default

post dyno graph

If it was a dynojet I would expect a faster car

but if its any other dyno they can make it say whatever they want
kingtal0n is offline  
Old 06-25-2019, 10:37 PM
  #7  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default


Mustang dyno... if this was any other shop Iíd consider the possibly but this shop is extremely reputable ... owner is a great guy and theyíve built/tuned cars for many people I know .
Brendyn G is offline  
Old 06-26-2019, 12:08 PM
  #8  
10 Second Club
iTrader: (4)
 
Darth_V8r's Avatar
 
Join Date: Jul 2014
Location: My own internal universe
Posts: 7,354
Received 26 Likes on 22 Posts
Default

What rear gear?
Darth_V8r is online now  
Old 06-26-2019, 02:39 PM
  #9  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Darth_V8r View Post
What rear gear?
3:23. I thought of this too as this is trash but still thought it should be doing a little bit better . Maybe Iím wrong though
Brendyn G is offline  
Old 06-26-2019, 02:46 PM
  #10  
10 Second Club
iTrader: (4)
 
Darth_V8r's Avatar
 
Join Date: Jul 2014
Location: My own internal universe
Posts: 7,354
Received 26 Likes on 22 Posts
Default

Originally Posted by Brendyn G View Post
3:23. I thought of this too as this is trash but still thought it should be doing a little bit better . Maybe Iím wrong though
it'll be hard to launch much better without gear. Something else -- your dyno curve was still going up, so I'm wondering --what is your shift point? you might simply need to raise your shift points. If you're peaking at 6300, you should be shifting around 6800.
Darth_V8r is online now  
Old 06-26-2019, 05:06 PM
  #11  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Darth_V8r View Post
it'll be hard to launch much better without gear. Something else -- your dyno curve was still going up, so I'm wondering --what is your shift point? you might simply need to raise your shift points. If you're peaking at 6300, you should be shifting around 6800.
Not even sure if itís that high. Will definitely check that out was actually thinking the same thing. Are stock ls1s with springs and push rods are good to rev to 6800?
Brendyn G is offline  
Old 06-26-2019, 05:18 PM
  #12  
10 Second Club
iTrader: (4)
 
Darth_V8r's Avatar
 
Join Date: Jul 2014
Location: My own internal universe
Posts: 7,354
Received 26 Likes on 22 Posts
Default

Originally Posted by Brendyn G
Not even sure if itís that high. Will definitely check that out was actually thinking the same thing. Are stock ls1s with springs and push rods are good to rev to 6800?
If your question is - can the bottom end take it? - the answer is yes. If you are saying stock springs and pushrods, I would go to 5/16 pushrods and psi1511 springs. The stock rockers are fine.

I wasn't sure on the phrasing which way you meant it.
Darth_V8r is online now  
Old 06-26-2019, 09:40 PM
  #13  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Darth_V8r View Post
If your question is - can the bottom end take it? - the answer is yes. If you are saying stock springs and pushrods, I would go to 5/16 pushrods and psi1511 springs. The stock rockers are fine.

I wasn't sure on the phrasing which way you meant it.
Sorry for the confusion, I put the springs and push rods in the car that came with my Texas speed cam kit, so they are not stock .
Brendyn G is offline  
Old 06-27-2019, 07:39 AM
  #14  
10 Second Club
iTrader: (4)
 
Darth_V8r's Avatar
 
Join Date: Jul 2014
Location: My own internal universe
Posts: 7,354
Received 26 Likes on 22 Posts
Default

Originally Posted by Brendyn G View Post
Sorry for the confusion, I put the springs and push rods in the car that came with my Texas speed cam kit, so they are not stock .
Good! Then here is my thoughts. I think on your dyno curve, the operator did not rev it out far enough. I think your actual result if was fully revved out would be in the 405 range at 6300 RPM. And you're at 370 lbs of torque at 5000 RPM, which is about right. So the motor is working perfectly fine.

If there is anything in your tune, it would be raising the transmission shift points. if it's a manual, I would go with 6800. The bottom end can do that just fine. I have little direct experience with an auto, and have only built one hotrod with an auto, but you definitely need to be shifting at least 6500 just to get past peak power.

Hardware-wise, you do not mention converter. A 3600 stall converter will wake the car up if not already done. Coupled with 3.73 gears, your car will come to life.

Bottom line, i do not think the motor is the issue. Just have to work on the rest of the car some.
Darth_V8r is online now  
Old 06-27-2019, 08:42 AM
  #15  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Awesome, thank you for the good info. Iím gonna mess with the shift points this weekend for sure . Also the car has a 3200 converter . A bit small but Iím not huge into racing just want a number to make sure itís all working good .
Brendyn G is offline  
Old 06-27-2019, 09:14 AM
  #16  
12 Second Club
iTrader: (6)
 
Join Date: Jul 2016
Location: Langley BC
Posts: 87
Likes: 0
Received 0 Likes on 0 Posts
Default

There must be something going on here. The dyno numbers and trap speed don't seem to match. My 01 SS ran 13.6 @ 102 bone stock. With current mods it did 12.6 @ 108. OP's should be trapping significantly higher.

What converter is it?
jlangley is offline  
Old 06-27-2019, 10:40 AM
  #17  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by jlangley View Post
There must be something going on here. The dyno numbers and trap speed don't seem to match. My 01 SS ran 13.6 @ 102 bone stock. With current mods it did 12.6 @ 108. OP's should be trapping significantly higher.

What converter is it?
I agree . Itís a summit branded 3200 believe itís made by Hughes ? The car still runs good also, was pretty even with a 2019 coyote last night on the highway from 60. The track is slightly uphill that I ran at, might take a few mph off but not a ton.
Brendyn G is offline  
Old 06-27-2019, 11:30 AM
  #18  
12 Second Club
iTrader: (6)
 
Join Date: Jul 2016
Location: Langley BC
Posts: 87
Likes: 0
Received 0 Likes on 0 Posts
Default

You're about 100 hp more than stock at the wheels. That should get you around 10 mph trap speed imo. I'm no expert but I suspect the converter is the problem.
jlangley is offline  
Old 06-27-2019, 02:18 PM
  #19  
Teching In
Thread Starter
 
Join Date: Jan 2019
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by jlangley View Post
You're about 100 hp more than stock at the wheels. That should get you around 10 mph trap speed imo. I'm no expert but I suspect the converter is the problem.
i could definitely see this. Iím thinking itís not a real ďproblemĒ as it is just a bad setup considering the converter is brand new.
Brendyn G is offline  
Old 06-27-2019, 04:55 PM
  #20  
LS1Tech Sponsor
iTrader: (4)
 
LSX Power Tuning's Avatar
 
Join Date: Mar 2013
Location: Brenham TX
Posts: 2,246
Likes: 0
Received 0 Likes on 0 Posts
Default

Need to check air fuel while at the track...also need to check converter slip....one of those will probably explain the low mph.
__________________

Full Service LSX Shop
HP Tuners, EFI Live, SCT, Holley, BS3, FAST XFI
Holley Certified Installer & Tuner
MSD, Brian Tooley, HP Tuners, EFI Live, Holley, Edge, Superchips +100's more

Email, Remote, Mail Order, Dyno, Street & Track Tuning
*WEBPAGE* *FACEBOOK* *ONLINE STORE*

LSX Power Tuning is online now  

Thread Tools
Search this Thread

About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: