lq9 into a c4??
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
The negatives
The two big things here are smog checks and adapting everything to work with your instrument panel which won't work any more, so you need to make a new instrument panel.
1. You would have to have a vehicle speed sensor and a speedo cable
2. some sort of tach interface box,
3. some way to get outside air under your hood and add an air filter
4. custom headers and exhaust with 4 O2 sensors
5. modified trans and custom driveshaft
6. modified torque arm, (no place for a crossmember)
7. adapt all the accessories....pwr steering, A/C, smog pump, alt. etc.
8. modified bigger radiator,
9. modified fuel lines and return lines,
10. modified cooling fan system, (LQ9 has an engine driven fan)
11. Modify the oil pan for clearance
12. Mount the new ECM
13. Modify the new wiring harness
14. fabricate a resistor bank to simulate sensors you are not going to use
15. add an oil cooler
The positives:
1. you can buy engine mounts
2. you can buy trans adapters
3. you can buy a harness
4. you can buy exhaust
5. you can buy an engine complete for about $3500
6. You can buy a corvette LS-1 pan and modify it
7. You can buy a custom radiator
after about $8,000, you will wish you bought a good used TPI engine and made it work with your stuff.
The two big things here are smog checks and adapting everything to work with your instrument panel which won't work any more, so you need to make a new instrument panel.
1. You would have to have a vehicle speed sensor and a speedo cable
2. some sort of tach interface box,
3. some way to get outside air under your hood and add an air filter
4. custom headers and exhaust with 4 O2 sensors
5. modified trans and custom driveshaft
6. modified torque arm, (no place for a crossmember)
7. adapt all the accessories....pwr steering, A/C, smog pump, alt. etc.
8. modified bigger radiator,
9. modified fuel lines and return lines,
10. modified cooling fan system, (LQ9 has an engine driven fan)
11. Modify the oil pan for clearance
12. Mount the new ECM
13. Modify the new wiring harness
14. fabricate a resistor bank to simulate sensors you are not going to use
15. add an oil cooler
The positives:
1. you can buy engine mounts
2. you can buy trans adapters
3. you can buy a harness
4. you can buy exhaust
5. you can buy an engine complete for about $3500
6. You can buy a corvette LS-1 pan and modify it
7. You can buy a custom radiator
after about $8,000, you will wish you bought a good used TPI engine and made it work with your stuff.
Racer
Joined: Aug 2008
Posts: 457
Likes: 2
The negatives
The two big things here are smog checks and adapting everything to work with your instrument panel which won't work any more, so you need to make a new instrument panel.
1. You would have to have a vehicle speed sensor and a speedo cable
2. some sort of tach interface box,
3. some way to get outside air under your hood and add an air filter
4. custom headers and exhaust with 4 O2 sensors
5. modified trans and custom driveshaft
6. modified torque arm, (no place for a crossmember)
7. adapt all the accessories....pwr steering, A/C, smog pump, alt. etc.
8. modified bigger radiator,
9. modified fuel lines and return lines,
10. modified cooling fan system, (LQ9 has an engine driven fan)
11. Modify the oil pan for clearance
12. Mount the new ECM
13. Modify the new wiring harness
14. fabricate a resistor bank to simulate sensors you are not going to use
15. add an oil cooler
The positives:
1. you can buy engine mounts
2. you can buy trans adapters
3. you can buy a harness
4. you can buy exhaust
5. you can buy an engine complete for about $3500
6. You can buy a corvette LS-1 pan and modify it
7. You can buy a custom radiator
after about $8,000, you will wish you bought a good used TPI engine and made it work with your stuff.
The two big things here are smog checks and adapting everything to work with your instrument panel which won't work any more, so you need to make a new instrument panel.
1. You would have to have a vehicle speed sensor and a speedo cable
2. some sort of tach interface box,
3. some way to get outside air under your hood and add an air filter
4. custom headers and exhaust with 4 O2 sensors
5. modified trans and custom driveshaft
6. modified torque arm, (no place for a crossmember)
7. adapt all the accessories....pwr steering, A/C, smog pump, alt. etc.
8. modified bigger radiator,
9. modified fuel lines and return lines,
10. modified cooling fan system, (LQ9 has an engine driven fan)
11. Modify the oil pan for clearance
12. Mount the new ECM
13. Modify the new wiring harness
14. fabricate a resistor bank to simulate sensors you are not going to use
15. add an oil cooler
The positives:
1. you can buy engine mounts
2. you can buy trans adapters
3. you can buy a harness
4. you can buy exhaust
5. you can buy an engine complete for about $3500
6. You can buy a corvette LS-1 pan and modify it
7. You can buy a custom radiator
after about $8,000, you will wish you bought a good used TPI engine and made it work with your stuff.
Melting Slicks
Joined: Mar 2004
Posts: 2,141
Likes: 2
From: Pittsburgh Pa
there is like 700 threads about this if you would either learn to scroll down or use the search function.
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
The negatives
The two big things here are smog checks and adapting everything to work with your instrument panel which won't work any more, so you need to make a new instrument panel.
1. You would have to have a vehicle speed sensor and a speedo cable
2. some sort of tach interface box,
3. some way to get outside air under your hood and add an air filter
4. custom headers and exhaust with 4 O2 sensors
5. modified trans and custom driveshaft
6. modified torque arm, (no place for a crossmember)
7. adapt all the accessories....pwr steering, A/C, smog pump, alt. etc.
8. modified bigger radiator,
9. modified fuel lines and return lines,
10. modified cooling fan system, (LQ9 has an engine driven fan)
11. Modify the oil pan for clearance
12. Mount the new ECM
13. Modify the new wiring harness
14. fabricate a resistor bank to simulate sensors you are not going to use
15. add an oil cooler
The positives:
1. you can buy engine mounts
2. you can buy trans adapters
3. you can buy a harness
4. you can buy exhaust
5. you can buy an engine complete for about $3500
6. You can buy a corvette LS-1 pan and modify it
7. You can buy a custom radiator
after about $8,000, you will wish you bought a good used TPI engine and made it work with your stuff.
The two big things here are smog checks and adapting everything to work with your instrument panel which won't work any more, so you need to make a new instrument panel.
1. You would have to have a vehicle speed sensor and a speedo cable
2. some sort of tach interface box,
3. some way to get outside air under your hood and add an air filter
4. custom headers and exhaust with 4 O2 sensors
5. modified trans and custom driveshaft
6. modified torque arm, (no place for a crossmember)
7. adapt all the accessories....pwr steering, A/C, smog pump, alt. etc.
8. modified bigger radiator,
9. modified fuel lines and return lines,
10. modified cooling fan system, (LQ9 has an engine driven fan)
11. Modify the oil pan for clearance
12. Mount the new ECM
13. Modify the new wiring harness
14. fabricate a resistor bank to simulate sensors you are not going to use
15. add an oil cooler
The positives:
1. you can buy engine mounts
2. you can buy trans adapters
3. you can buy a harness
4. you can buy exhaust
5. you can buy an engine complete for about $3500
6. You can buy a corvette LS-1 pan and modify it
7. You can buy a custom radiator
after about $8,000, you will wish you bought a good used TPI engine and made it work with your stuff.
Racer
Joined: Aug 2008
Posts: 457
Likes: 2
[QUOTE=Mojave;1572096201]What's wrong with an LQ9? Yeah, it's a 'truck' engine, but it's a truck engine that blows away every L98 and LT1, especially with a few choice modifications (like a cam). I would have no reservations about swapping in an LQ9 (or an LQ4, or L92, or any other LSx based engine).
OK show me a LSX truck motor with no changes that got swaped into a c4 and it blows away a lt1.
OK show me a LSX truck motor with no changes that got swaped into a c4 and it blows away a lt1.
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Intermediate
Joined: May 2005
Posts: 42
Likes: 0
LQ9 is a 6.0 High Output Truck engine, found in Escalades and a few other models. Close to 350HP and if you add gen IV L92 heads to it will bring you close to 400HP and an added bonus is they are much cheaper to find then an LS1,,,,$1500-$2500 range. I want to put one in my '84 next year but carb it cause I dont want the wiring nightmare involved with fuel injection.
http://en.wikipedia.org/wiki/GM_Vortec_engine#LQ9
http://en.wikipedia.org/wiki/GM_Vortec_engine#LQ9
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
Cam-headers LQ9's are over 400 RWHP with nothing else. I've never, ever, EVER, seen a stock-head (not ported), stock intake N/A LT1 do 400 RWHP.
Burning Brakes
Joined: Dec 2007
Posts: 1,125
Likes: 8
From: Taft TN
347 hp and 380 ft/lbs of torque vs 300 and 330 ft/lbs. 50 more hp and 50 more ft/lbs is pretty good, and that is with the long runner truck intake. Throw an LS6 intake on it and I bet you'll pick up a bit more power.
Cam-headers LQ9's are over 400 RWHP with nothing else. I've never, ever, EVER, seen a stock-head (not ported), stock intake N/A LT1 do 400 RWHP.
Cam-headers LQ9's are over 400 RWHP with nothing else. I've never, ever, EVER, seen a stock-head (not ported), stock intake N/A LT1 do 400 RWHP.
there is also the ly6, which is 370hp. I have heard that a cam & tune will produce about 100 more hp using the VVT. Dont kno yet but I plan to find out.
Racer
Joined: Aug 2008
Posts: 457
Likes: 2
347 hp and 380 ft/lbs of torque vs 300 and 330 ft/lbs. 50 more hp and 50 more ft/lbs is pretty good, and that is with the long runner truck intake. Throw an LS6 intake on it and I bet you'll pick up a bit more power.
Cam-headers LQ9's are over 400 RWHP with nothing else. I've never, ever, EVER, seen a stock-head (not ported), stock intake N/A LT1 do 400 RWHP.
Cam-headers LQ9's are over 400 RWHP with nothing else. I've never, ever, EVER, seen a stock-head (not ported), stock intake N/A LT1 do 400 RWHP.
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
I'm really not sure what you are saying. Are you debating the factory power rating of the LSx engines? Are you saying 50 hp & 50 ft/lbs isn't a big step up? Are you saying LSx's don't make power with a few modifications? Are you saying there aren't any LSx swapped C4's?
If you are more specific, I can explain my logic further, and get some dyno charts to back up my 'cheap talk'. I'm certainly no engine god, but I do know LSx's make lots of power. I've got an LT4 that I built and LS1 (still stock), so I've wrenched on both (sometimes more than I'd like...).
Last edited by Mojave; Nov 10, 2009 at 12:13 AM.
Racer
Joined: Aug 2008
Posts: 457
Likes: 2
First off, it's you're, not your. Apparently talk isn't free, because you screwed it up.
I'm really not sure what you are saying. Are you debating the factory power rating of the LSx engines? Are you saying 50 hp & 50 ft/lbs isn't a big step up? Are you saying LSx's don't make power with a few modifications? Are you saying there aren't any LSx swapped C4's?
If you are more specific, I can explain my logic further, and get some dyno charts to back up my 'cheap talk'. I'm certainly no engine god, but I do know LSx's make lots of power. I've got an LT4 that I built and LS1 (still stock), so I've wrenched on both (sometimes more than I'd like...).
I'm really not sure what you are saying. Are you debating the factory power rating of the LSx engines? Are you saying 50 hp & 50 ft/lbs isn't a big step up? Are you saying LSx's don't make power with a few modifications? Are you saying there aren't any LSx swapped C4's?
If you are more specific, I can explain my logic further, and get some dyno charts to back up my 'cheap talk'. I'm certainly no engine god, but I do know LSx's make lots of power. I've got an LT4 that I built and LS1 (still stock), so I've wrenched on both (sometimes more than I'd like...).
Melting Slicks
Joined: Mar 2004
Posts: 2,141
Likes: 2
From: Pittsburgh Pa
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
As far as I know, no one has done that swap. So in one sense, you are right, I can't prove it. But on the flip side, you can't prove me wrong, and the numbers suggest it would be faster. If you have some numbers that suggest otherwise, please share.
Racer
Joined: Aug 2008
Posts: 457
Likes: 2
Actually, your spelling was perfect (all your words were properly spelled), but your grammar was incorrect.
As far as I know, no one has done that swap. So in one sense, you are right, I can't prove it. But on the flip side, you can't prove me wrong, and the numbers suggest it would be faster. If you have some numbers that suggest otherwise, please share.
As far as I know, no one has done that swap. So in one sense, you are right, I can't prove it. But on the flip side, you can't prove me wrong, and the numbers suggest it would be faster. If you have some numbers that suggest otherwise, please share.