ZL1 Info on first upgrades - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

GOAT · 07-29-2014, 04:23 PM

So my fellow ZL1 owners I have a CAI, 2.55 upper, larger idler with HD Belt, cutouts, and a tune. Running 14PSI now.
I am having a hesitation issue under full load above 3500 to 3800 starting in 3rd all the way up my rpm band until I change gears then it starts all over in the next gear past 3800. Any ideas on causes? I've read everything from needing injectors already up to faulty MAF sensors. My last dyno tune I was at 555rwhp/549rwtq. Anybody run into the same issue so soon in a build?

Botally Tone · 07-29-2014, 04:31 PM

Have you tried cleaning your MAF sensor?

GOAT · 07-29-2014, 04:37 PM

Quote:

Originally Posted by Botally Tone

Have you tried cleaning your MAF sensor?

Yes I have done that.

Bigtime53 · 07-29-2014, 06:27 PM

It does sound like you need injectors.I think you have maxed them out with the horsepower you have.That would be the first thing I would do.You might want to take it to a tuner somewhere and they will be able to tell you what is going on.

GOAT · 07-29-2014, 06:41 PM

Quote:

Originally Posted by Bigtime53

It does sound like you need injectors.I think you have maxed them out with the horsepower you have.That would be the first thing I would do.You might want to take it to a tuner somewhere and they will be able to tell you what is going on.

Yes my tuner said I need more fuel...so injectors then pump but I don't see that is necessary when hennesey, livernoius, ligenfelter are not doing fuel upgrades until 650 700 hp range. Makes me think he is not tuning my car correctly. Also seen speed density tuning forum talk about fixing this issue. Just wanted to find out what everyone thought...

2013 ZL1 #7860 · 07-29-2014, 08:42 PM

Try re gaping the spark plugs a little smaller and see how that goes. My last boosted car did that. Smaller gap in the spark plugs fixed it. Like .02-.05 smaller. Good luck!

GOAT · 07-29-2014, 09:32 PM

Quote:

Originally Posted by 2013 ZL1 #7860

Try re gaping the spark plugs a little smaller and see how that goes. My last boosted car did that. Smaller gap in the spark plugs fixed it. Like .02-.05 smaller. Good luck!

I have my plugs at .034 right now. Put in TR6IX about a week ago. Is that small enough gap?

jon6.0 · 07-29-2014, 09:46 PM

Quote:

Originally Posted by GOAT

I have my plugs at .034 right now. Put in TR6IX about a week ago. Is that small enough gap?

Try .030", but be real careful with those iridium plugs when gapping them. I ran .028" on my C6 at 750rwhp with TR7ix plugs.

Did the tuner tell you what your injector duty cycle was? Anything over 90% and you should get new injectors. Also, did they mention if your fuel pressure was dropping off? Fuel pressure dropping will also cause your injector duty cycle to go up. You should worry about stable fuel flow and pressure first. If you have that and you are still over 90% IDC then you need larger injectors.

GOAT · 07-29-2014, 09:49 PM

Ok will do. Thanks

ZO6 Bryan · 07-29-2014, 11:46 PM

You MAY need bigger injectors, BUT that wouldn't cause your symptoms. Look at the tune. Who tuned it? Probably you are feeling knock retard or burst knock kicking in. Or they pulled so much timing out you're feeling that hesitation. At 14 psi boost, your power is down from what I'd expect also.

GOAT · 07-30-2014, 12:42 AM

Quote:

Originally Posted by jon6.0

Try .030", but be real careful with those iridium plugs when gapping them. I ran .028" on my C6 at 750rwhp with TR7ix plugs.

Did the tuner tell you what your injector duty cycle was? Anything over 90% and you should get new injectors. Also, did they mention if your fuel pressure was dropping off? Fuel pressure dropping will also cause your injector duty cycle to go up. You should worry about stable fuel flow and pressure first. If you have that and you are still over 90% IDC then you need larger injectors.

I have a diablo sport so I will log some numbers tomorrow and get back to you guys. My tuner guy was no help when it came to giving me numbers he was pulling with EFI live like it was a secret.

vatechguy3 · 08-02-2014, 09:20 PM

update?

tony

GOAT · 08-02-2014, 09:45 PM

Quote:

Originally Posted by vatechguy3

update?

tony

Going a different route. Working with Mike over at vengeance racing to run a different tune. Buying an EFI live V2 tool so I can flash my own tunes he sends me. I'll go from their and post if it was my previous Crappy tuner guy or I really do need different fuel delivery setup.

jon6.0 · 08-02-2014, 10:06 PM

Good choice. A tuner not wanting to say what your injector duty cycles was is complete BS. Having EFI Live or HPT will allow you to have a daily driver tune and a race fuel tune if you so desire.

07-29-2014, 04:23 PM	#1
GOAT DiabloZL1 Drives: 14 ZL1 Join Date: Jan 2014 Location: CHARLESTON, SC Posts: 41 View My Garage	ZL1 Info on first upgrades So my fellow ZL1 owners I have a CAI, 2.55 upper, larger idler with HD Belt, cutouts, and a tune. Running 14PSI now. I am having a hesitation issue under full load above 3500 to 3800 starting in 3rd all the way up my rpm band until I change gears then it starts all over in the next gear past 3800. Any ideas on causes? I've read everything from needing injectors already up to faulty MAF sensors. My last dyno tune I was at 555rwhp/549rwtq. Anybody run into the same issue so soon in a build?

07-29-2014, 11:46 PM	#10
ZO6 Bryan Drives: 02 Z06, 95 Trans Am, 2012 ZL1 Join Date: Mar 2012 Location: Southeast Posts: 1,838 View My Garage	You MAY need bigger injectors, BUT that wouldn't cause your symptoms. Look at the tune. Who tuned it? Probably you are feeling knock retard or burst knock kicking in. Or they pulled so much timing out you're feeling that hesitation. At 14 psi boost, your power is down from what I'd expect also. __________________ Bryan 2018 ZL1 M6

08-02-2014, 09:20 PM	#12
vatechguy3 Drives: 2014 ZL1 M6 Join Date: Jul 2014 Location: Virginia Posts: 493	update? tony __________________ 2014 ZL1 M6 Bone stock, for now! 2001 Z28 M6 !cags, !air, FTP 85mm Lid, Z06 85mm MAF, P&P TB !4x4, Strano Springs, Strano Sways, Koni 4/4s, Watts Link ARH LTs, ARH catted Y, SLP catback with Dual/Dual Muffler, SLP CME and Valance OE Wheels Machined Face C5 DDs, 18x10.5s, with 295/35-18s on all 4 corners! 352rwhp and 366rwtq

08-02-2014, 10:06 PM	#14
jon6.0 Going for Plaid Drives: 2011 C6 Join Date: Jan 2010 Location: Phoenix Posts: 885	Good choice. A tuner not wanting to say what your injector duty cycles was is complete BS. Having EFI Live or HPT will allow you to have a daily driver tune and a race fuel tune if you so desire. __________________ 2014 ZL1, manual trans, carbon hood insert, Rotofab, Pacesetter 1 7/8" headers, 1" drop BMR springs, stock pulleys, 91 octane tune, 545rwhp & 515rwtq Serviced and modded by Cordes Performance. 2011 C6, 750rwhp, forged LS3, ported LSA heads, Vortech Ti-trim, 227/243 115+4 Lunati cam, ported LS3 intake, Alky Control methanol, Pfadt sways/shocks/trans mounts, Pfadt tri-y headers(Sold 6/28/14)

07-29-2014, 04:31 PM	#2
Botally Tone Drives: 2014 Ashen Gray ZL1 Join Date: Mar 2014 Location: Houston Posts: 119 View My Garage	Have you tried cleaning your MAF sensor?

07-29-2014, 06:27 PM	#4
Bigtime53 Drives: 2013 ZL1 Join Date: Mar 2013 Location: Oklahoma Posts: 2,298	It does sound like you need injectors.I think you have maxed them out with the horsepower you have.That would be the first thing I would do.You might want to take it to a tuner somewhere and they will be able to tell you what is going on.

07-29-2014, 08:42 PM	#6
2013 ZL1 #7860 Drives: 2013 ZL1 A6 #7860 Join Date: Apr 2014 Location: CO, USA Posts: 1,279	Try re gaping the spark plugs a little smaller and see how that goes. My last boosted car did that. Smaller gap in the spark plugs fixed it. Like .02-.05 smaller. Good luck!

07-29-2014, 09:49 PM	#9
GOAT DiabloZL1 Drives: 14 ZL1 Join Date: Jan 2014 Location: CHARLESTON, SC Posts: 41 View My Garage	Ok will do. Thanks