04-03-2012, 10:00 PM | #1 |
Drives: 2012 2SS M6 Join Date: Dec 2011
Location: Phoenix, AZ
Posts: 768
|
Long cranking time with cam and tune
A couple weeks ago I had a cam, headers, and high flow cats installed and a tune on the dyno. I'm real happy with the way it runs. Even the driveability is great which surprised me a bit considering the cam specs (dur 227/243; lift .614/.624; LSA 113). One thing that seems a bit strange is that it consistently cranks for about 2.5 seconds every time I start it. Stone cold, warm, or anything in between the cranking time is exactly the same. I mentioned it to the guy who did the work and he said that is normal with the cam and that he could fix it by drilling a small hole in the throttle plate. I decided to pass on that for now because I didn't want a hole in my new throttle body. It's not a big deal to me but I'm curious about it.
If you have a cam with similar specs, does you car crank longer since it was installed? I believe I read that this can be fixed with the tune. If that is the case, what needs to be changed in the tune?
__________________
2012 2SS Convertible
Magnuson, Headers, Cam, JRE Tune. 563 HP. |
04-03-2012, 11:30 PM | #2 |
Drives: 2021 Crush ZL1 1LE Join Date: Oct 2009
Location: Sierra Vista, AZ
Posts: 1,119
|
FWIW - Mine starts the same or quicker than stock with the cam. Just have some extra fuel smell til it warms up. Its garaged at night so it never gets too cold.
__________________
2021 Crush ZL1 1LE |
04-03-2012, 11:43 PM | #3 |
CamaroFans.com
|
My cam specs were very close to yours and it started just like it did when stock...
231/247 617/624 113 Here's a Start up Video |
04-04-2012, 07:54 AM | #4 |
Drives: 1999 Trans Am Join Date: Jul 2009
Location: Bridgewater,Ma
Posts: 2,017
|
It should start pretty much the same as a stock car.
Does it happen to back fire at startup? I've seen a few installers put the wrong Cam gear in there which causes a longtime to start. |
04-04-2012, 09:12 AM | #5 |
SIP
Drives: 2011 1SS, L99, A6 , Silver Ice Join Date: Aug 2010
Location: Pearland, Texas
Posts: 205
|
You may need to disconect the battery and let it sit for 15 min.
Start it and let it reset the T-body. I had one do that to me and thats what I did and it was fine after that. I disconected the battery in the truck by just removeing the neg post. Try it it cant hurt
__________________
"My Birthday gift from my wife on 10/19/2010 "
|
04-04-2012, 09:25 AM | #6 | ||
Drives: 2012 2SS M6 Join Date: Dec 2011
Location: Phoenix, AZ
Posts: 768
|
Quote:
Quote:
__________________
2012 2SS Convertible
Magnuson, Headers, Cam, JRE Tune. 563 HP. |
||
04-04-2012, 09:29 AM | #7 | ||
Drives: 2012 2SS M6 Join Date: Dec 2011
Location: Phoenix, AZ
Posts: 768
|
Quote:
Quote:
I was hoping one of the tuners would see this and say what they actually do with a tune to correct this, if there really is a parameter in the tables for start up enrichment or something that got missed with mine.
__________________
2012 2SS Convertible
Magnuson, Headers, Cam, JRE Tune. 563 HP. |
||
04-04-2012, 09:52 AM | #8 | |
Drives: 1999 Trans Am Join Date: Jul 2009
Location: Bridgewater,Ma
Posts: 2,017
|
Quote:
But seeing that suggestion also tells me the startup part of the tune is probly not even close which is why it takes so long to start. |
|
04-04-2012, 09:54 AM | #9 | |
Account Suspended
Drives: TAMPA TUNING FACEBOOK & INSTAGRAM Join Date: Oct 2010
Location: Tampa, Fl
Posts: 3,044
|
Quote:
Your tuner has to make sure the start up (cranking) spark and fueling ( injector rate) is corrected for the new cam. |
|
04-04-2012, 09:58 AM | #10 |
Drilling the hole is what used to be done in the late 80's and early/mid 90's when a cam was swapped and tuning was more of a PIA then, as mentioned by slowhawk and tampa tuning you might want to have someone else look at the tuning
__________________
2010 Camaro SS Whipple SC, CAI Inc Intake, TSP 1 7/8" LT headers no cats, 3" magnaflow exhaust, HPT, RX Catch Can, LSR Toe Rods, LSR Trailing Arms, ALKY Control Meth, McLeod RXT Twin Disc, ZL1 fuel pump, 3.73 ZL1 Differential Kit, BTR PDS Stage 2 Cam, Tuned by SLOWHAWK Performance Bridgewater MA
|
|
04-04-2012, 11:36 AM | #11 |
Drives: cts-v Join Date: Dec 2011
Location: Mooresville, NC
Posts: 506
|
Cranking spark and start-up airflow need to be looked at,as long as injectors and other rest of airflow/fueling are set up properly. Should start up just like it used to, without extended time or throttle input.
__________________
|
04-04-2012, 02:58 PM | #12 |
Drives: 2010 2SS/RS IOM M6 Join Date: May 2011
Location: Abu Dhabi, UAE
Posts: 288
|
Yeah, no reason at all to drill the TB blade. Sounds like cranking spark and possibly base running airflow needs work.
__________________
Whipple 2.9L S/C, ARH LT's, Flowmaster AMT, HPTuners
|
04-04-2012, 03:50 PM | #13 | |
Drives: BLUE CAMARO ZL1 1LE M6 Join Date: Jun 2009
Location: ON THE DYNO WATERBURY CT.
Posts: 15,215
|
Quote:
Drilling a Hole is a Big Mistake with DBW cars. You have limitless Air available with DBW for Idle. The older cars with cable throttle non adjustable tps and limited IAC motors this was a necessary evil on radical builds. Ted.
__________________
www.jannettyracing.com
Celebrating 37 years Performance parts, Installation, Fabrication, Dyno tuning, Remote custom tuning, and alignments. 203-753-7223 Waterbury CT. 06705 email tedj@jannettyracing.com |
|
04-04-2012, 05:46 PM | #14 |
Drives: 2012 2SS M6 Join Date: Dec 2011
Location: Phoenix, AZ
Posts: 768
|
First of all, looks like Stic It deserves some sort of prize for his suggestion to unhook the battery. My car starts just like MLee's in the video above now, at least on warm and half cooled starts. I'll check the totally cold start tomorrow morning, but I think this is resolved.
I'm afraid I didn't explain the situation very well in my initial post. The shop that installed the parts doesn't do their own tuning. The mechanical work was done well and the base tune was adjusted on a dyno to make sure the AFR was OK (about 12.3 dropping to 12.0 at 4500 and up). It's the finer points of the tune like the cranking time and the torque management settings that I'm curious about. I want to learn as much as possible so I can go back to the shop with intelligent and concise questions. That way they'll only have to go back to the guy who did the tuning once to get my answers. Here's the long story if anyone is interested. The work was done at a local dealer who does a lot of performance work, some on brand new cars. I've seen one of those, a supercharged and cammed Camaro, and it is impressive. They told me they will stand behind the warranty on the car as long as I bring it back to them. After they installed the parts they loaded a base tune from a third party and we drove it over to the dyno. They ran it and emailed the data log to the tuner who emailed back a revised tune which they loaded and ran it again. It took a couple of times to get the AFR where they wanted it and that was it. Now I have some questions about the tune and I'm guessing the shop will have to go back to the tuner to get answers so I want to choose my questions carefully. Other than the long cranking, which looks to be fixed, the only thing I'm still wondering about is the torque management. I'm happy with the performance until I read those posts from people saying their tires break loose if they floor it at 20 mph without touching the clutch. Then I start wondering about the torque management on mine. I was hoping to find some way I could check that myself, but it looks like the HP software and a laptop is the only way way and I have neither. On the other hand, maybe they don't want it turned off because of the warranty situation. I'll probably just have to ask about it.
__________________
2012 2SS Convertible
Magnuson, Headers, Cam, JRE Tune. 563 HP. |
|
|
Thread Tools | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Official 1/4 Mile (V8) 2010+ Camaro Fast List | Merc | Dragstrip and Launch Techniques Discussion | 3652 | 08-17-2023 02:50 PM |
Unofficial 1/4 Mile (V8) 2010+ Camaro Fast List | Merc | Dragstrip and Launch Techniques Discussion | 250 | 04-01-2014 10:40 AM |
Tutorial: Can I tune my own vehicle? | bluetorp | Tuning / Diagnostics -- engine and transmission | 11 | 01-23-2012 07:04 AM |
Manual vs Auto GTAHVIT vs PQ... The video wars. | 76z28 | 5th Gen Camaro SS LS LT General Discussions | 443 | 08-26-2010 12:26 PM |