engine swap options for a 1990 c4 ?
10-24-2019, 04:58 PM
#1
engine swap options for a 1990 c4 ?
Im hoping to get some opinions and help on c4 engine swap options, my l98 is starting to show some blue smoke on startup so im planning for the future, Options at that time would be rebuild the l98 or a swap, What is involved with either a ls1 ,ls2 or ls3 swap, or another option? what would be involved with these swaps, modification needed and parts needed, any help would be much appreciated
10-24-2019, 05:21 PM
#2
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St. Jude Donor '05
You dont need an ls to make any power, that stuff gets posted by kids who have no gen 1 experience.
There is nothing magicla about an lsx....plan on modding one youll need a chit ton of $.
There is nothing magicla about an lsx....plan on modding one youll need a chit ton of $.
Last edited by cv67; 10-24-2019 at 05:22 PM.
10-24-2019, 05:37 PM
#3
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2015 C2 of Year Finalist
you can buy valve seals really cheap or spend thousands on a new engine
10-24-2019, 05:56 PM
#4
I'm starting the same process in my mind right now.
It's shaping up to be a big (406, 434) small block vs a 6.0, 6.2 or 408 LS.
I see a couple of key problems with the small block:
1) Any intake that'll fit under the hood is too damn expensive. TPIS? $1000. Pro Flo XT... might BARELY fit, still $1000.
2) To go big power on a small block (+600hp N/A) reliably, you need an aftermarket block for big displacement. That usually means lots of $ for the strength an LS block brings, dead stock.
For m car, either will need an aftermarket pcm, so that's a wash. Might be easier with the small block to keep my 1985 dash, which I would like to do.
The LS will have an issue with the accessories, that'll be expensive to solve.
Oh, and LS's ARE magic. Better cam circle diameter, stronger 6 bolt block, vastly better sealing, massive modern aftermarket support, just a ton of upside. They get stuck in everything that moves because they kick ***.
The cost/hp equation is complicated here but one thing sticks out like a sore thumb:
The L98 intake (good in 1985, a total turd now) along with the low hood height on our cars is a serious problem and drives LOTS of cost.
It's shaping up to be a big (406, 434) small block vs a 6.0, 6.2 or 408 LS.
I see a couple of key problems with the small block:
1) Any intake that'll fit under the hood is too damn expensive. TPIS? $1000. Pro Flo XT... might BARELY fit, still $1000.
2) To go big power on a small block (+600hp N/A) reliably, you need an aftermarket block for big displacement. That usually means lots of $ for the strength an LS block brings, dead stock.
For m car, either will need an aftermarket pcm, so that's a wash. Might be easier with the small block to keep my 1985 dash, which I would like to do.
The LS will have an issue with the accessories, that'll be expensive to solve.
Oh, and LS's ARE magic. Better cam circle diameter, stronger 6 bolt block, vastly better sealing, massive modern aftermarket support, just a ton of upside. They get stuck in everything that moves because they kick ***.
The cost/hp equation is complicated here but one thing sticks out like a sore thumb:
The L98 intake (good in 1985, a total turd now) along with the low hood height on our cars is a serious problem and drives LOTS of cost.
10-24-2019, 05:59 PM
#5
You could rebuild it or maybe do something like this... http://www.brphotrods.com/products/8...tte/index.html
I don't see the point of insulting folks for asking about an LS swap...this forum is apparently filled with jackasses.
I don't see the point of insulting folks for asking about an LS swap...this forum is apparently filled with jackasses.
Last edited by Jaye Bass; 10-24-2019 at 06:00 PM.
10-24-2019, 09:02 PM
#6
Race Director
I'm starting the same process in my mind right now.
It's shaping up to be a big (406, 434) small block vs a 6.0, 6.2 or 408 LS.
I see a couple of key problems with the small block:
1) Any intake that'll fit under the hood is too damn expensive. TPIS? $1000. Pro Flo XT... might BARELY fit, still $1000.
2) To go big power on a small block (+600hp N/A) reliably, you need an aftermarket block for big displacement. That usually means lots of $ for the strength an LS block brings, dead stock.
For m car, either will need an aftermarket pcm, so that's a wash. Might be easier with the small block to keep my 1985 dash, which I would like to do.
The LS will have an issue with the accessories, that'll be expensive to solve.
Oh, and LS's ARE magic. Better cam circle diameter, stronger 6 bolt block, vastly better sealing, massive modern aftermarket support, just a ton of upside. They get stuck in everything that moves because they kick ***.
The cost/hp equation is complicated here but one thing sticks out like a sore thumb:
The L98 intake (good in 1985, a total turd now) along with the low hood height on our cars is a serious problem and drives LOTS of cost.
It's shaping up to be a big (406, 434) small block vs a 6.0, 6.2 or 408 LS.
I see a couple of key problems with the small block:
1) Any intake that'll fit under the hood is too damn expensive. TPIS? $1000. Pro Flo XT... might BARELY fit, still $1000.
2) To go big power on a small block (+600hp N/A) reliably, you need an aftermarket block for big displacement. That usually means lots of $ for the strength an LS block brings, dead stock.
For m car, either will need an aftermarket pcm, so that's a wash. Might be easier with the small block to keep my 1985 dash, which I would like to do.
The LS will have an issue with the accessories, that'll be expensive to solve.
Oh, and LS's ARE magic. Better cam circle diameter, stronger 6 bolt block, vastly better sealing, massive modern aftermarket support, just a ton of upside. They get stuck in everything that moves because they kick ***.
The cost/hp equation is complicated here but one thing sticks out like a sore thumb:
The L98 intake (good in 1985, a total turd now) along with the low hood height on our cars is a serious problem and drives LOTS of cost.
its to the point where these swaps are done in every car, so often so much they are boring. Id rather see someone take a 500 CI 76 cadillac coupe deville motor and stuff it into a c4 vs an lsx motor.
ive thought long and hard about lsx swap for weight savings (when my time comes due on my 93 lt1) .
however its rare someone here puts in an alum block ls3. Its always steel block truck motors
weight is where we have our only
advantage vs an amg gt65 , a nissan gt-r, a tesla.
those are all superior cars in the sense they are more useful everyday, more storage, seat more people,
so weight aside, when I started digging into it..i noticed....
afr heads can be slapped onto lt1’s and sbc these comp ported heads flow ls3 numbers (albeit thats comparing a highly modd head to a stock ls3 head).
add boost and the lsx magic starts disappearing. Oh yeah, and if making more than 800 rwhp on an alum block, the alum block has been documented to bore distort so youll need an iron block lsx and your weight advantage is gone).
even so if i make 1000 rwhp on a boosted lsx, but only 870 on a boosted sbc - who really cares.
either will be so traction limited its gonna come down to the better driver, tires, lighter car, etc
so my take. If you go ls swap go with the aluminum block !!!!
Last edited by dizwiz24; 10-24-2019 at 09:03 PM.
10-24-2019, 09:38 PM
#8
Being the best OHV V8 on Earth, ever, will do that.
Gee, I wonder why.
They're dirt cheap, and a vanilla 5.3 liter out of a work truck with vinyl seats will smash any LT series motor put in any C4 stock for stock, and when the mods start it gets even uglier.
You're starting to catch on...
800 rwhp on a small block? Reliably? Yeah, that's a Dart block. Probably a Little M.
$3000 street price. For the block alone.
Show me a production small block that can hold 800 rwhp and I've got a bridge Ill sell ya in Brooklyn. Iron LS's? Bring it on.
6 liter LS block? Why bother? You can get the whole engine, soup to nuts, with a PCM for a grand.
Lots of folks, mostly the ones who don't want to unload $3000 on a block to pull 870 rhwp out of a SBC.
Gee, I wonder why.
They're dirt cheap, and a vanilla 5.3 liter out of a work truck with vinyl seats will smash any LT series motor put in any C4 stock for stock, and when the mods start it gets even uglier.
You're starting to catch on...
$3000 street price. For the block alone.
Show me a production small block that can hold 800 rwhp and I've got a bridge Ill sell ya in Brooklyn. Iron LS's? Bring it on.
6 liter LS block? Why bother? You can get the whole engine, soup to nuts, with a PCM for a grand.
Lots of folks, mostly the ones who don't want to unload $3000 on a block to pull 870 rhwp out of a SBC.
10-24-2019, 09:43 PM
#9
Race Director
I'm starting the same process in my mind right now.
It's shaping up to be a big (406, 434) small block vs a 6.0, 6.2 or 408 LS.
I see a couple of key problems with the small block:
1) Any intake that'll fit under the hood is too damn expensive. TPIS? $1000. Pro Flo XT... might BARELY fit, still $1000.
2) To go big power on a small block (+600hp N/A) reliably, you need an aftermarket block for big displacement. That usually means lots of $ for the strength an LS block brings, dead stock.
For m car, either will need an aftermarket pcm, so that's a wash. Might be easier with the small block to keep my 1985 dash, which I would like to do.
The LS will have an issue with the accessories, that'll be expensive to solve.
Oh, and LS's ARE magic. Better cam circle diameter, stronger 6 bolt block, vastly better sealing, massive modern aftermarket support, just a ton of upside. They get stuck in everything that moves because they kick ***.
The cost/hp equation is complicated here but one thing sticks out like a sore thumb:
The L98 intake (good in 1985, a total turd now) along with the low hood height on our cars is a serious problem and drives LOTS of cost.
It's shaping up to be a big (406, 434) small block vs a 6.0, 6.2 or 408 LS.
I see a couple of key problems with the small block:
1) Any intake that'll fit under the hood is too damn expensive. TPIS? $1000. Pro Flo XT... might BARELY fit, still $1000.
2) To go big power on a small block (+600hp N/A) reliably, you need an aftermarket block for big displacement. That usually means lots of $ for the strength an LS block brings, dead stock.
For m car, either will need an aftermarket pcm, so that's a wash. Might be easier with the small block to keep my 1985 dash, which I would like to do.
The LS will have an issue with the accessories, that'll be expensive to solve.
Oh, and LS's ARE magic. Better cam circle diameter, stronger 6 bolt block, vastly better sealing, massive modern aftermarket support, just a ton of upside. They get stuck in everything that moves because they kick ***.
The cost/hp equation is complicated here but one thing sticks out like a sore thumb:
The L98 intake (good in 1985, a total turd now) along with the low hood height on our cars is a serious problem and drives LOTS of cost.
My buddy at work has this setup, it broke immediately. So he started picking up various BIG money parts and rebuilding along the way... and it STILL doesnt work.
If you were to just do a really mild 5.3 build to try to make 350hp or so, it wouldnt be too expensive. Heads, cam, intake, and you're there. But you're also 5 grand (minimum) deep in it once you've done that and a swap.
10-24-2019, 10:50 PM
#10
A dead stock 5.3 out of a boring old 2014 Silverado work truck is 355hp.
Mods required to the motor to make the power you're claiming?
None. Not a thing. Rip it out of a wreck and bolt it in.
GM made... oh... a million or so of them, EVERY YEAR, so it ain't like they're rare or expensive.
That's SAE net. So, more like ~400 on an engine dyno.
As far as $ goes:
LS7 based, 427 in^3, 715hp, ALUMINUM BLOCK, hyd. roller lifter pump gas motor:
https://www.shafiroff.com/chevy-ls-p...ls7-engine.php
$15,750
SBC based, 434 in^3, 700 hp, IRON BLOCK (Dart), hyd. roller lifter pump gas motor:
https://www.shafiroff.com/chevy-pump...bigdawg-hr.php
$16,400
To make 15 LESS horsepower, the SBC has to spin to 6900 rpm while the LS peaks at 6400.
16 years ago I made 400 rwhp with a heads/cam/header/tune LS1 in a 2001 Camaro SS that drove like a dream. Good vacuum, idled fine ( nice lope), rock-solid reliable. Drove the thing from Michigan to Kentucky and back for a Camaro event. Never gave a hint of problems. I have PLENTY of experience with LS's, thanks.
Last edited by PacerX; 10-24-2019 at 10:53 PM.
10-24-2019, 11:18 PM
#11
Race Director
Where do you guys get this nonsense? 350hp crank?
A dead stock 5.3 out of a boring old 2014 Silverado work truck is 355hp.
Mods required to the motor to make the power you're claiming?
None. Not a thing. Rip it out of a wreck and bolt it in.
GM made... oh... a million or so of them, EVERY YEAR, so it ain't like they're rare or expensive.
That's SAE net. So, more like ~400 on an engine dyno.
As far as $ goes:
LS7 based, 427 in^3, 715hp, ALUMINUM BLOCK, hyd. roller lifter pump gas motor:
https://www.shafiroff.com/chevy-ls-p...ls7-engine.php
$15,750
SBC based, 434 in^3, 700 hp, IRON BLOCK (Dart), hyd. roller lifter pump gas motor:
https://www.shafiroff.com/chevy-pump...bigdawg-hr.php
$16,400
To make 15 LESS horsepower, the SBC has to spin to 6900 rpm while the LS peaks at 6400.
16 years ago I made 400 rwhp with a heads/cam/header/tune LS1 in a 2001 Camaro SS that drove like a dream. Good vacuum, idled fine ( nice lope), rock-solid reliable. Drove the thing from Michigan to Kentucky and back for a Camaro event. Never gave a hint of problems. I have PLENTY of experience with LS's, thanks.
A dead stock 5.3 out of a boring old 2014 Silverado work truck is 355hp.
Mods required to the motor to make the power you're claiming?
None. Not a thing. Rip it out of a wreck and bolt it in.
GM made... oh... a million or so of them, EVERY YEAR, so it ain't like they're rare or expensive.
That's SAE net. So, more like ~400 on an engine dyno.
As far as $ goes:
LS7 based, 427 in^3, 715hp, ALUMINUM BLOCK, hyd. roller lifter pump gas motor:
https://www.shafiroff.com/chevy-ls-p...ls7-engine.php
$15,750
SBC based, 434 in^3, 700 hp, IRON BLOCK (Dart), hyd. roller lifter pump gas motor:
https://www.shafiroff.com/chevy-pump...bigdawg-hr.php
$16,400
To make 15 LESS horsepower, the SBC has to spin to 6900 rpm while the LS peaks at 6400.
16 years ago I made 400 rwhp with a heads/cam/header/tune LS1 in a 2001 Camaro SS that drove like a dream. Good vacuum, idled fine ( nice lope), rock-solid reliable. Drove the thing from Michigan to Kentucky and back for a Camaro event. Never gave a hint of problems. I have PLENTY of experience with LS's, thanks.
So say you get that 5 3 for 500 bucks, you're gonna have at least a grand in new heads, intake manifold, will be 500 bucks for a dorman one (many would just go fast lsxr for more like 1000), cam is probably 300 bucks, you've got almost 2 grand in just parts to go feom.250ish hp to 3xx. That's not even including the swap headers, accessories, cross members, trans adapters, electronics... none of that.
Dont get me wrong, it's all doable. People do it all the time. But it's not as cheap and easy as the internet would have you believe.
BTW, those 2010 to 2014 higher hp 5.3s mostly start around 2k. But those are also known for failing lifters due to the AFM system. So who knows how long your junkyard motor will last. You can of course swap out to solid lifted and tune AFM out... but more money and effort.
Also... 400rwhp out of a h/c ls2? What the hell kind of insane cam were you running that gave you 150+ hp over stock? I could see 400 crank, but 400whp? That's a bit hard to believe unless you had the sort of dyno the guys on 1320 use with a major correction factor to boost your ego, lol. My best buddy has a 98 zs2 with the same build but also a fast lsx intake and he's probably 400ish crank.
Last edited by FAUEE; 10-24-2019 at 11:23 PM.
10-25-2019, 05:04 PM
#12
2014 5.3s arent the 500 dollar junkyard ones though. The 5.3s you get cheap are early 00s, making like mid 200s hp stock. And it's not like it's a "lift out, drop in, plug in, done" sort of swap. It's a decent amount of work to swap in an ls and get everything working. Work and money.
So say you get that 5 3 for 500 bucks, you're gonna have at least a grand in new heads, intake manifold, will be 500 bucks for a dorman one (many would just go fast lsxr for more like 1000), cam is probably 300 bucks, you've got almost 2 grand in just parts to go feom.250ish hp to 3xx. That's not even including the swap headers, accessories, cross members, trans adapters, electronics... none of that.
Dont get me wrong, it's all doable. People do it all the time. But it's not as cheap and easy as the internet would have you believe.
BTW, those 2010 to 2014 higher hp 5.3s mostly start around 2k. But those are also known for failing lifters due to the AFM system. So who knows how long your junkyard motor will last. You can of course swap out to solid lifted and tune AFM out... but more money and effort.
Also... 400rwhp out of a h/c ls2? What the hell kind of insane cam were you running that gave you 150+ hp over stock? I could see 400 crank, but 400whp? That's a bit hard to believe unless you had the sort of dyno the guys on 1320 use with a major correction factor to boost your ego, lol. My best buddy has a 98 zs2 with the same build but also a fast lsx intake and he's probably 400ish crank.
So say you get that 5 3 for 500 bucks, you're gonna have at least a grand in new heads, intake manifold, will be 500 bucks for a dorman one (many would just go fast lsxr for more like 1000), cam is probably 300 bucks, you've got almost 2 grand in just parts to go feom.250ish hp to 3xx. That's not even including the swap headers, accessories, cross members, trans adapters, electronics... none of that.
Dont get me wrong, it's all doable. People do it all the time. But it's not as cheap and easy as the internet would have you believe.
BTW, those 2010 to 2014 higher hp 5.3s mostly start around 2k. But those are also known for failing lifters due to the AFM system. So who knows how long your junkyard motor will last. You can of course swap out to solid lifted and tune AFM out... but more money and effort.
Also... 400rwhp out of a h/c ls2? What the hell kind of insane cam were you running that gave you 150+ hp over stock? I could see 400 crank, but 400whp? That's a bit hard to believe unless you had the sort of dyno the guys on 1320 use with a major correction factor to boost your ego, lol. My best buddy has a 98 zs2 with the same build but also a fast lsx intake and he's probably 400ish crank.
That's SAE net. So, more like ~400 on an engine dyno.
10-25-2019, 05:30 PM
#13
Team Owner
Pro Mechanic
Jaye,
An "engine dyno" and SAE NET produce very different numbers, on he "same engine". HERE is some good reading for you....
An "engine dyno" and SAE NET produce very different numbers, on he "same engine". HERE is some good reading for you....
10-25-2019, 06:08 PM
#15
Team Owner
Pro Mechanic
Yes. No. Depends. Actually we've talked Enging dyno (GROSS), Engine dyno (NET) and wheel hp. Did you READ THE LINK???
READ THE LINK
LINK
.
READ THE LINK
LINK
.
Last edited by Tom400CFI; 10-25-2019 at 06:12 PM.
10-25-2019, 06:24 PM
#17
Le Mans Master
Anything is possible. GEN 1 is physically smaller, ls you make a little more power for the same money. Once you start pushing either and want reliability the money goes up quickly. I've seen just as many windowed LS as I have gen 1.... better intakes for efi on the LS however getting the thing to fit is fun. Gen 1 engines look nicer to me but that's me. What are you wanting to do?
Side note... Those 14up 5.3s are really weak... the claimed 355 hp is there, sure. But having a few in the fleet they are pretty gutless... even tuned. The VVT is what gets that number. The big thing is valve angle and the LS has that advantage. But no matter the SB2 blows either away...
Side note... Those 14up 5.3s are really weak... the claimed 355 hp is there, sure. But having a few in the fleet they are pretty gutless... even tuned. The VVT is what gets that number. The big thing is valve angle and the LS has that advantage. But no matter the SB2 blows either away...
10-25-2019, 06:26 PM
#18
Team Owner
Pro Mechanic
10-25-2019, 06:32 PM
#19
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Unless you have some specific goal in mind, just have your current engine rebuilt and valve seals replaced. Have them blueprint it, freshen things up in the valvetrain, etc. No need for LS.