Help needed! LQ4 w/ LS3 heads
Thread Starter
Teching In
Joined: Feb 2017
Posts: 34
Likes: 3
From: Russia
Help needed! LQ4 w/ LS3 heads Hello everyone!
I've just bought an LQ4 used shortblock (all stock internals, pretty good condition).
And also I have:
- both LS3 heads
- LS3 "Hot Cam"
- LS3 intake
- LS3 flat top pistons (without even valve "notches").
Couple of questions:
1) Can 6.0L LQ4 be safely overbored to LS3 pistons' size? Or it's a 50/50 success story?
2) Because of the LS3 cam I'll need a front engine cover with cam sensor but for what should I do with the LQ4's original cam sensor's plug?
3) What engine harness and PCM should I look for? I have none of those now. Engine will be swaped into a BMW if it can make sense (custom wiring harness for the rest of my car anyway).
Thanks in advance!
I've just bought an LQ4 used shortblock (all stock internals, pretty good condition).
And also I have:
- both LS3 heads
- LS3 "Hot Cam"
- LS3 intake
- LS3 flat top pistons (without even valve "notches").
Couple of questions:
1) Can 6.0L LQ4 be safely overbored to LS3 pistons' size? Or it's a 50/50 success story?
2) Because of the LS3 cam I'll need a front engine cover with cam sensor but for what should I do with the LQ4's original cam sensor's plug?
3) What engine harness and PCM should I look for? I have none of those now. Engine will be swaped into a BMW if it can make sense (custom wiring harness for the rest of my car anyway).
Thanks in advance!
Hello everyone!
I've just bought an LQ4 used shortblock (all stock internals, pretty good condition).
And also I have:
- both LS3 heads
- LS3 "Hot Cam"
- LS3 intake
- LS3 flat top pistons (without even valve "notches").
Couple of questions:
1) Can 6.0L LQ4 be safely overbored to LS3 pistons' size? Or it's a 50/50 success story?
2) Because of the LS3 cam I'll need a front engine cover with cam sensor but for what should I do with the LQ4's original cam sensor's plug?
3) What engine harness and PCM should I look for? I have none of those now. Engine will be swaped into a BMW if it can make sense (custom wiring harness for the rest of my car anyway).
Thanks in advance!
I've just bought an LQ4 used shortblock (all stock internals, pretty good condition).
And also I have:
- both LS3 heads
- LS3 "Hot Cam"
- LS3 intake
- LS3 flat top pistons (without even valve "notches").
Couple of questions:
1) Can 6.0L LQ4 be safely overbored to LS3 pistons' size? Or it's a 50/50 success story?
2) Because of the LS3 cam I'll need a front engine cover with cam sensor but for what should I do with the LQ4's original cam sensor's plug?
3) What engine harness and PCM should I look for? I have none of those now. Engine will be swaped into a BMW if it can make sense (custom wiring harness for the rest of my car anyway).
Thanks in advance!
2)Leave it in. Nasty oily mess if you pull it out.
3)Depends. Speak with whomever is building your custom harness. Lots of info about that on this forum so some more research wouldn't hurt either.
Thread Starter
Teching In
Joined: Feb 2017
Posts: 34
Likes: 3
From: Russia
2) I mean if I'll be using "gen4" harness along with PCM - then maybe I should use a "Gen4" flat valley cover with no knock sensor's in it? Because I'll have to place them right on the engine block's sides...?
3) I'm building all the car by myself (except PCM tuning only) so it's all on my own...
There's no junkyards with Camaros, Vettes etc. in my area where I can find a "Gen4" PCM and harness - but a lot of Escalades, Tahoes...
May I rephrase my question - what "truck/SUV" should I look for?
Maybe some of their wiring is easy to work with or it doen't matter?
I'll search that kind of info anyway but someone's 0.02 will help anyway I guess!
The only reason I'm asking about any Gen4 harness is because I have an LS3 Hot Cam on my shelf but maybe it will be much smarter to use any Gen3 PCM and harness out of any pickup and just buy a brand new cam for $300-400 to work with?
Last edited by 340i; Jan 7, 2018 at 05:02 AM.
Thread Starter
Teching In
Joined: Feb 2017
Posts: 34
Likes: 3
From: Russia
But what about MAF sensor?
I've got FAST 92mm DBC TB along with LS3 intake and MAF from '04 Tahoe (along with PCM and harness) which is much smaller... is there any ~100mm GM MAF sensors that will work with Gen3 PCM?
I've found "DELPHI AF10043" (it should be an OEM replacement for GM part), it's ~90mm.
Last edited by 340i; Jan 14, 2018 at 08:40 AM.
Trending Topics
Got it, thanks guys!
But what about MAF sensor?
I've got FAST 92mm DBC TB along with LS3 intake and MAF from '04 Tahoe (along with PCM and harness) which is much smaller... is there any ~100mm GM MAF sensors that will work with Gen3 PCM?
I've found "DELPHI AF10043" (it should be an OEM replacement for GM part), it's ~90mm.
But what about MAF sensor?
I've got FAST 92mm DBC TB along with LS3 intake and MAF from '04 Tahoe (along with PCM and harness) which is much smaller... is there any ~100mm GM MAF sensors that will work with Gen3 PCM?
I've found "DELPHI AF10043" (it should be an OEM replacement for GM part), it's ~90mm.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thread Starter
Teching In
Joined: Feb 2017
Posts: 34
Likes: 3
From: Russia
Thanks for the input!
Went to Google... ))