LT4 Dyno Results
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
LT4 Dyno Results
Well, I took the LT4 out to the club dyno Saturday and I was pretty impressed.
295.4 peak hp
303.6 peak tq
That's a stock LT4 with modifications to the car of: muffler elims (with 2.5 pipe in place - that i need to get fixed to 2.75 or 3"), K&N, cut airlid, and i am running an OBDI computer instead of OBDII. The wideband was reading pretty lean, so i need to do some modifications to my computer to fix that and I've been told I should get back 5-10rwhp out of that. I'm not sure what the smaller pipes in place of the mufflers is doing to it either. I'm going to try and get those two things fixed up and then dyno again.
I wanted to put my OBDII computer on there to see if my programming is hurting or helping it - but the exhaust i bought with the muff elims was from an LT1 so it's missing the rear O2 bung on the drivers side... so it wouldn't have run right at all (which i can attest to after driving it with the stock computer).
That was run 3.. run 2 i ran the same thing as above but without the cut air lid and I pulled 293rwhp & 300rwtq.
I'll have some better numbers around 325-330 after swapping cams in a few months ;) :D
[Modified by GlockLT4, 8:30 AM 7/21/2003]
[Modified by GlockLT4, 8:35 AM 7/21/2003]
295.4 peak hp
303.6 peak tq
That's a stock LT4 with modifications to the car of: muffler elims (with 2.5 pipe in place - that i need to get fixed to 2.75 or 3"), K&N, cut airlid, and i am running an OBDI computer instead of OBDII. The wideband was reading pretty lean, so i need to do some modifications to my computer to fix that and I've been told I should get back 5-10rwhp out of that. I'm not sure what the smaller pipes in place of the mufflers is doing to it either. I'm going to try and get those two things fixed up and then dyno again.
I wanted to put my OBDII computer on there to see if my programming is hurting or helping it - but the exhaust i bought with the muff elims was from an LT1 so it's missing the rear O2 bung on the drivers side... so it wouldn't have run right at all (which i can attest to after driving it with the stock computer).
That was run 3.. run 2 i ran the same thing as above but without the cut air lid and I pulled 293rwhp & 300rwtq.
I'll have some better numbers around 325-330 after swapping cams in a few months ;) :D
[Modified by GlockLT4, 8:30 AM 7/21/2003]
[Modified by GlockLT4, 8:35 AM 7/21/2003]
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Re: LT4 Dyno Results (GlockLT4)
:cool: :cheers:
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
Re: LT4 Dyno Results (Hammer)
Nice numbers :cheers:
Why are you running OBDI?
Why are you running OBDI?
Thread Starter
Team Owner
Joined: Apr 2001
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From: Dallas TX
Re: LT4 Dyno Results (JasonL)
I don't think the 2.5" exhaust is holding you back, at least not at the moment. It's certainly not holding my car back :thumbs:
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Le Mans Master
Joined: Mar 2001
Posts: 9,464
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From: Modesto CA
Re: LT4 Dyno Results (JasonL)
I don't think the 2.5" exhaust is holding you back, at least not at the moment. It's certainly not holding my car back :thumbs:
I'd listen to Jason. :) I was THERE when this dude put down 322rwhp with his LT4 (Same mods as you; K&N & Cut Off Mufflers)
Thread Starter
Team Owner
Joined: Apr 2001
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From: Dallas TX
Re: LT4 Dyno Results (TIMSPEED)
I don't think the 2.5" exhaust is holding you back, at least not at the moment. It's certainly not holding my car back :thumbs:
Glock,
I'd listen to Jason. :) I was THERE when this dude put down 322rwhp with his LT4 (Same mods as you; K&N & Cut Off Mufflers)
Glock,
I'd listen to Jason. :) I was THERE when this dude put down 322rwhp with his LT4 (Same mods as you; K&N & Cut Off Mufflers)
Le Mans Master
Joined: Mar 2001
Posts: 9,464
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From: Modesto CA
Re: LT4 Dyno Results (GlockLT4)
What was the temp out? What was the A/F ratio like?
Thread Starter
Team Owner
Joined: Apr 2001
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From: Dallas TX
Re: LT4 Dyno Results (TIMSPEED)
What was the temp out? What was the A/F ratio like?
It was prolly around 75º in the shop, the shop was also right at sea level. Jason's car is the REASON I want an LT4...It was funny that day, cuz we had a pool going on, to see if we could guess what everyone's car would do. Since Jason's car was near stock, we all guessed right around 300hp..well...we we all SHOCKED when it hit 322!!
It was prolly around 75º in the shop, the shop was also right at sea level. Jason's car is the REASON I want an LT4...It was funny that day, cuz we had a pool going on, to see if we could guess what everyone's car would do. Since Jason's car was near stock, we all guessed right around 300hp..well...we we all SHOCKED when it hit 322!!
Melting Slicks
Joined: Apr 2000
Posts: 3,198
Likes: 2
From: Northern CA
Re: LT4 Dyno Results (GlockLT4)
Well Tim is mostly correct :D My car had muffler eliminators (2.5") and also a TPIS "flipped" air box (hole in the radiator shroud). Yeah I think temps were mid 70's, but the dyno guy used a fan which brought the car down to normal highway temps.
http://mage.wildfyre.com/~jhliao/car..._06jun2001.jpg
I've wondered if the gains were due to the intake or exhuast... I'd guess about half and half. Hope that helps.
http://mage.wildfyre.com/~jhliao/car..._06jun2001.jpg
I've wondered if the gains were due to the intake or exhuast... I'd guess about half and half. Hope that helps.
