PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Si5 Camshaft question

Thread Tools
 
Search this Thread
 
Old Oct 29, 2016 | 02:37 PM
  #1  
lostmytune's Avatar
Thread Starter
Teching In
iTrader: (4)
 
Joined: May 2011
Posts: 3
Likes: 0
Default Si5 Camshaft question

After trying to do some research I came up with some information but not nearly enough to really answer this question. Being that I am not a tuner I have no idea what the ins and outs are as far as setting knock, misfire, or anything else to that nature. Recently I picked up another fbody. Car is a cam only car with supporting mods. Lifters, springs, push rods, so forth. The cam is a Speed Inc Si5 camshaft. Here is my question:

Car runs great, idles up and down a little bit until at OT but other wise idle is clean and clear. Car pulls amazing in all gears, granted I have been trying to keep my foot out of it. The CEL is on for a random misfire. Now the previous owner told me the car was tuned by a local guy in NC that was known for tuning ls cars there. Of course...that tells me nothing. Is it possible that this camshaft can throw a false misfire that needs to be set/adjusted in HpT? I had read somewhere that once you get near the 600 lift area that this was possible but I am trying to get better information from someone that has delt with it first hand. Again the car runs great, doesnt miss a beat, and will pull like a train, which if it WASN'T tuned I feel it would run like ***. Car will be getting retuned come spring, just trying to do some home work.
Reply
Old Oct 30, 2016 | 12:39 PM
  #2  
JakeFusion's Avatar
Super Hulk Smash
20 Year Member
Liked
Loved
Community Favorite
iTrader: (7)
 
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
Default

Lift has nothing to do with it. Overlap of the cam is what you're looking at.

You'll need to reduce the sensitivity in your misfire tables. The PCM can see a cam as a misfire event. There are three misfire tables in the LS computer for low, medium, and high rpm. With a cam, you just max them all out to 32767.
Reply




All times are GMT -5. The time now is 04:31 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE