2.38 vs 2.55 upper - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Tim B · 03-23-2013, 04:44 PM

What is the normal power difference between them. Ordered a ADM ported snout, throttle body and heat exchanger.. Since it is coming with a 10 bolt upper that is easy to change pulleys , I got a LPE 2.38 upper and a HX reservoir.
Trying to pick up another 45-50hp then I am done for a while. Well maybe some stickys for the rear to go after some friends GT-500.
Thanks Tim

hognutz · 03-23-2013, 09:25 PM

From what I have seen you just have to have some machining done of the snout because of the smaller diameter.

The people who run them swear buy it as it is the cheapest way to 20,000+ blower rpm's and 15-16psi.

on the flip side I think some peopel shy away from it because it requires machining of the snout and maybe not wanting that much boost.

I do not know how much injector duty cycle you have left after adding that much boost either.

Stephen12ZL1 · 03-23-2013, 09:38 PM

the 2.38 is great I hear and belt slippage is no issue either. You must have an injector upgrade to handle this much boost/airflow. ADM is going to do it right for sure. From a simple boost standpoint it is probably 20hp difference

Tim B · 03-23-2013, 10:35 PM

Thanks for the replies. I have plenty of injector. They are below 60% duty at full throttle. When I had the blower off last time we stuck in ID 850s. I was a little worried about belt slippage. I know it is driving the blower pretty hard with my rev limiter set at 6600. Should we dyno with everything off (ptm modes)? I should have results middle of next week.
Thanks Tim

Stephen12ZL1 · 03-23-2013, 11:02 PM

great...I thought you had mentioned Id850s in a previous post. Dyno with all nannies off...hold down the TC button for 7 seconds until both icons are illuminated. PTM modes are for the track!

Tim B · 03-24-2013, 01:53 PM

Thanks Stephen,
I am ready to get some nicer weather to get to Richmond to race with you.
Tim

The Baron · 03-24-2013, 03:19 PM

Had the 2.38 on wifes caddy for 10, 000 daily driven miles.. her car DOES NOT have injectors and with the pully cold air and ls9 cam makes almost 600 on a mustang dyno through a auto..

My zl has a 2.38 and a 10% lower now.. that is about 16-17 #s with everything, cam, headers, ported blower, the works. Do the 2.38 and don't look back

If you do end up getting a squealer ( my name for blowers that get noisy needle bearings behind the snout, just get ahold of me and ill tell you how to fix it.

Tim B · 03-24-2013, 03:58 PM

What size cam and springs are you running? If you dont mind disclosing that. That will be the next mods later in the future. I will be adding ADM ported snout/ 90mm throttle body, Adm heat exchanger, LPE 2.38 10 bolt upper and reservoir. To go with my Arh long tubes and 160stat and Id 850s. This will probably be it till after summer. Tim

The Baron · 03-24-2013, 07:12 PM

If you are looking for big hp I can get you hooked up with my zl1 cam setup but honestly and know shops all talk about leaving hp on the table but I absolutely love the drivability and the huge tq the ls9 cam gives..instant on like right now.. my wifes car is got stock crap cts v exhaust and everything.. its a ruthless killer on the highway lol . It went 126.6 mph in the quarter so it runs pretty good for a completely stock drive.

Tim B · 03-27-2013, 07:44 PM

Just got back from the dyno and it did 635 whp. I am very happy with the results. Gained a little over 50 hp from the ported snout, throttle body and 2.38 pulley. The boost was 15 lbs at 6400rpm. The ADM cooler was 3 times as thick as the factory unit, so hopefully it will be repeatable at the track in warmer weather. Thanks for the advise guys. Tim

The Baron · 03-27-2013, 07:56 PM

That's pretty good. What gas is in tje car? 91?

Tim B · 03-27-2013, 08:24 PM

BP 93 octane. I guess we are lucky in Virginia to still have access to 93. Thanks again Baron it was a your posts on the 2.38 that planted the idea for it. I will contact you if I need blower bearing help. Tim

EVLZL1 · 03-27-2013, 08:44 PM

Those are great gains, what are your total mods so far? I took Barons advise also on the 2.38, and went with the super chiller instead of an upgraded HX. I also did the Roto-Fab CAI/Big Gulp, and ID 850's which were installed today. I'm getting tuned on Friday with 91 octane so i'm curious to see how mine compares to yours.

Tim B · 03-27-2013, 09:03 PM

Thanks,
I have the roto fab cai, arh hedders, id 850s, adm ported snout and 90mm throttle body, 2.38 upper, lpe hx resrvoir and adm hx. Tim

03-23-2013, 04:44 PM	#1
Tim B Drives: 2013 ZL1 / 2008 z51 vette Join Date: Nov 2012 Location: Virginia Beach Posts: 47	2.38 vs 2.55 upper What is the normal power difference between them. Ordered a ADM ported snout, throttle body and heat exchanger.. Since it is coming with a 10 bolt upper that is easy to change pulleys , I got a LPE 2.38 upper and a HX reservoir. Trying to pick up another 45-50hp then I am done for a while. Well maybe some stickys for the rear to go after some friends GT-500. Thanks Tim __________________ 2013 Blk M6 ZL1 685 whp / 11.32 so far

03-23-2013, 09:25 PM	#2
hognutz Drives: 2013 ZL1 Join Date: Oct 2011 Location: tangent or Posts: 2,985	From what I have seen you just have to have some machining done of the snout because of the smaller diameter. The people who run them swear buy it as it is the cheapest way to 20,000+ blower rpm's and 15-16psi. on the flip side I think some peopel shy away from it because it requires machining of the snout and maybe not wanting that much boost. I do not know how much injector duty cycle you have left after adding that much boost either. __________________ 2016 2SS 2020 super duty on 37's

03-23-2013, 09:38 PM	#3
Stephen12ZL1 Drives: '21 ZLE A10 Join Date: May 2012 Location: Mechanicsville, VA Posts: 6,824	the 2.38 is great I hear and belt slippage is no issue either. You must have an injector upgrade to handle this much boost/airflow. ADM is going to do it right for sure. From a simple boost standpoint it is probably 20hp difference __________________ '21 ZLE A10 Wild Cherry PDR 2:00.78 VIR Full 10.68@131.69 1.68 60' '17 ZL1 A10 Mosaic Black PDR/Nav 2:03.08 VIR Full 11.003@129.2 1.75 (sold) '15 Z/28 #325 Black a/c & stereo. 2:10.1 VIR Full (sold) '12 ZL1 A6 Black 10.52@131 1.55 60' 2:13 VIR Full (sold)

03-23-2013, 10:35 PM	#4
Tim B Drives: 2013 ZL1 / 2008 z51 vette Join Date: Nov 2012 Location: Virginia Beach Posts: 47	Thanks for the replies. I have plenty of injector. They are below 60% duty at full throttle. When I had the blower off last time we stuck in ID 850s. I was a little worried about belt slippage. I know it is driving the blower pretty hard with my rev limiter set at 6600. Should we dyno with everything off (ptm modes)? I should have results middle of next week. Thanks Tim __________________ 2013 Blk M6 ZL1 685 whp / 11.32 so far

03-23-2013, 11:02 PM	#5
Stephen12ZL1 Drives: '21 ZLE A10 Join Date: May 2012 Location: Mechanicsville, VA Posts: 6,824	great...I thought you had mentioned Id850s in a previous post. Dyno with all nannies off...hold down the TC button for 7 seconds until both icons are illuminated. PTM modes are for the track! __________________ '21 ZLE A10 Wild Cherry PDR 2:00.78 VIR Full 10.68@131.69 1.68 60' '17 ZL1 A10 Mosaic Black PDR/Nav 2:03.08 VIR Full 11.003@129.2 1.75 (sold) '15 Z/28 #325 Black a/c & stereo. 2:10.1 VIR Full (sold) '12 ZL1 A6 Black 10.52@131 1.55 60' 2:13 VIR Full (sold)

03-24-2013, 01:53 PM	#6
Tim B Drives: 2013 ZL1 / 2008 z51 vette Join Date: Nov 2012 Location: Virginia Beach Posts: 47	Thanks Stephen, I am ready to get some nicer weather to get to Richmond to race with you. Tim __________________ 2013 Blk M6 ZL1 685 whp / 11.32 so far

03-24-2013, 03:19 PM	#7
The Baron Drives: 2013 zl1 Join Date: Nov 2012 Location: st louis Posts: 838	Had the 2.38 on wifes caddy for 10, 000 daily driven miles.. her car DOES NOT have injectors and with the pully cold air and ls9 cam makes almost 600 on a mustang dyno through a auto.. My zl has a 2.38 and a 10% lower now.. that is about 16-17 #s with everything, cam, headers, ported blower, the works. Do the 2.38 and don't look back If you do end up getting a squealer ( my name for blowers that get noisy needle bearings behind the snout, just get ahold of me and ill tell you how to fix it. __________________ 2011 cts-v coupe (pinky) wifes car.. ls9 cam c.a.i. 11.44 2007 corvette vert ..retired.. 2013 zl1 stock blower stock ci 20" wheels 10.36 135...so far..

03-24-2013, 03:58 PM	#8
Tim B Drives: 2013 ZL1 / 2008 z51 vette Join Date: Nov 2012 Location: Virginia Beach Posts: 47	What size cam and springs are you running? If you dont mind disclosing that. That will be the next mods later in the future. I will be adding ADM ported snout/ 90mm throttle body, Adm heat exchanger, LPE 2.38 10 bolt upper and reservoir. To go with my Arh long tubes and 160stat and Id 850s. This will probably be it till after summer. Tim __________________ 2013 Blk M6 ZL1 685 whp / 11.32 so far

03-24-2013, 07:12 PM	#9
The Baron Drives: 2013 zl1 Join Date: Nov 2012 Location: st louis Posts: 838	If you are looking for big hp I can get you hooked up with my zl1 cam setup but honestly and know shops all talk about leaving hp on the table but I absolutely love the drivability and the huge tq the ls9 cam gives..instant on like right now.. my wifes car is got stock crap cts v exhaust and everything.. its a ruthless killer on the highway lol . It went 126.6 mph in the quarter so it runs pretty good for a completely stock drive. __________________ 2011 cts-v coupe (pinky) wifes car.. ls9 cam c.a.i. 11.44 2007 corvette vert ..retired.. 2013 zl1 stock blower stock ci 20" wheels 10.36 135...so far..

03-27-2013, 07:44 PM	#10
Tim B Drives: 2013 ZL1 / 2008 z51 vette Join Date: Nov 2012 Location: Virginia Beach Posts: 47	Just got back from the dyno and it did 635 whp. I am very happy with the results. Gained a little over 50 hp from the ported snout, throttle body and 2.38 pulley. The boost was 15 lbs at 6400rpm. The ADM cooler was 3 times as thick as the factory unit, so hopefully it will be repeatable at the track in warmer weather. Thanks for the advise guys. Tim __________________ 2013 Blk M6 ZL1 685 whp / 11.32 so far

03-27-2013, 07:56 PM	#11
The Baron Drives: 2013 zl1 Join Date: Nov 2012 Location: st louis Posts: 838	That's pretty good. What gas is in tje car? 91? __________________ 2011 cts-v coupe (pinky) wifes car.. ls9 cam c.a.i. 11.44 2007 corvette vert ..retired.. 2013 zl1 stock blower stock ci 20" wheels 10.36 135...so far..

03-27-2013, 08:24 PM	#12
Tim B Drives: 2013 ZL1 / 2008 z51 vette Join Date: Nov 2012 Location: Virginia Beach Posts: 47	BP 93 octane. I guess we are lucky in Virginia to still have access to 93. Thanks again Baron it was a your posts on the 2.38 that planted the idea for it. I will contact you if I need blower bearing help. Tim __________________ 2013 Blk M6 ZL1 685 whp / 11.32 so far

03-27-2013, 08:44 PM	#13
EVLZL1 Drives: '13 Black ZL1,MN6,Suede pkg, Join Date: Oct 2012 Location: Scottsdale Posts: 90	Those are great gains, what are your total mods so far? I took Barons advise also on the 2.38, and went with the super chiller instead of an upgraded HX. I also did the Roto-Fab CAI/Big Gulp, and ID 850's which were installed today. I'm getting tuned on Friday with 91 octane so i'm curious to see how mine compares to yours.

03-27-2013, 09:03 PM	#14
Tim B Drives: 2013 ZL1 / 2008 z51 vette Join Date: Nov 2012 Location: Virginia Beach Posts: 47	Thanks, I have the roto fab cai, arh hedders, id 850s, adm ported snout and 90mm throttle body, 2.38 upper, lpe hx resrvoir and adm hx. Tim __________________ 2013 Blk M6 ZL1 685 whp / 11.32 so far