hot85vette

Has anybody swapped a lq9 into a c4? Some people have been telling me to go with that instead of an lt1 it would be cheaper and probly faster as well. any info would help thankyou

coupeguy2001

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.

lt1396corvette

I never liked the idea of putting a truck motor in a car.If I was going to do it I would buy the vette LSX motor.I would much rather build up a gen1 motor.

pr0zac

there is like 700 threads about this if you would either learn to scroll down or use the search function.

Mojave

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).

That's sort of right. The stock dash will continue to work, except for the MPG read outs. If that requires a new dash, then yeah, but otherwise, it will work fine. You don't need 4 O2 sensors, the rear 2 are quite easy to tune out. You can use your factory fans, don't have to use a mechanical. F-body accessories fit fine. F-body pan doesn't require any modifications to clear (C5 batwing pan is huge and is not recommended). You don't need any custom radiator, the stock one is fine.

lt1396corvette

[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.

COPO

I would put one in mine.

CorvetteMike2024

Pardon my stupidity, but whats a LQ9?

Corvette Mike

Rodzilla71

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

pologreen1

great info /\

Mojave

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.

COPO

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.

lt1396corvette

So your talking on paper.No real world experience.Thats what I thought.Talk is cheap.And you do alot of it.

Mojave

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...).

lt1396corvette

Thanks for the spell check.You said an lq9 blows away a lt1.So i want to see an lq9 in a c4 vs an lt1.Not a modified lq9

pr0zac

you're out of your mind and very argumentative

lt1396corvette

Wow,you should'nt be talking

pr0zac

at least i have somewhat of a clue of the subjects i may or may not agree with.

Mojave

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.

lt1396corvette

The way I look at it GM built this motor to go in a truck,not a car.For it to work in a car you are gonna have to mod it.That's why I said I would go with the the vette motor for a swap.Just sounds like a better and easier swap.I don't think there are people on the F-body forum swaping truck motors in there cars.So I don't see why someone would want to do it with there vette.