lavamadness

I'm currently researching doing an engine buildup, and I was wondering which was the better way to go. Build up a regular SBC (350 or 383), or swap in an LS1 and modify that to achieve my goals.

My current goal is fun daily driver what will run 12s at the track. 20+ MPG on highway (the more the better), passes emissions (sniffer).

I suspect an LS1 would cost more (if I need to modify if to get my goals), but if gas mileage was way better, and emissions easier to pass, and the cost not THAT much more, it might be worth it.

Cronic3rd

A smallblock will be easier to get more power from. An ls1 will get better gas mileage , pass emitions and the car will handle better. But they are *** expensive to mod right now.

TexasLT1

How do you figure that? LS1's respond very well to mods. I can name off so many LS1's that are putting down 450+ rwhp with heads, cam, intake and long tubes. They come stock with something like 330-350 at the crank. And besides, anything you can do to a regular SBC you can do to the LS1 and get more power from it. The only downside to the LS1 is the cost. Parts cost a little more, but not prohibitively more. If I had the little bit extra to do an LS1 swap, I wouldn't hesitate.



*edit* Also think about this. A stock F-body LS1, as shown by Thirdgen Resource, will get you very near the 12's. Mate a T-56 with it, and you're pulling down what, like 23 mpg city/28 highway.

lavamadness

What would it take to get 450-500hp at the crank from an LS1?

biff85ta

A cam heads and headers.

Cronic3rd

That was said assuming that he works for money, more HP would be easier from a traditonal SBC.

Granted an ls1 will do it better (or more efficently) but not dollar for dollar.

How much is a good running ls1? $1500 on a good day? There is a bone yard around me that sells 350's running (or not...) for $150. Compared to an LS1 leaves enough for good heads and a cam. Granted mileage would suck but 400hp isn't too far fetched from a cammed 350 with Heads.

How much would 400hp cost from an LS1?

KYL98

400hp from an LS1 would cost about $500 or so.....just put a complete exhaust on it....and it would make 400hp at the crank, more if you put a good intake on it. Let's not forget about the weight savings either.....that always allows for a faster car, correct? Look at those ****ty Hondas....weigh 1800lbs with 300hp and go 9's......I would go with the LS1 anyday. You could get 500hp out of an LS1 without even opening the motor up.......

lavamadness

I thought you couldn't fit anything other than the stock LS1 manifolds in a thirdgen? Or did you just mean a cat back?

How much hp do stock LS1 heads support?

89 Iroc Z

LS1's have 325 rear wheel hp stock that’s 350+ at the crank completely stock. A gen I SBC with that much power is about the same cost as a used LS1. If you put heads and cam you will have 450+ hp.

As I see it there no con's of a ls1:
- 150 lb lighter
- Gobs of power
- SFI, Great gas mileage
- Easy to pass smog tests
- DIS, a coil per cylinder

If you have the money buy a LS1.

TexasLT1

It takes custom headers if you want anything other than stock manifolds, but those flow pretty good for manifolds. For a stock engine, they are fine. If you want serious power out of it, you'd have to get some custom headers made.

KYL98

Edelbrock makes shortie headers for the LS1 now that fit the thirdgens frame.....keep in mind, they ARE NOT made for a 3rd gen...but will fit. Those headers, along with some "mild" porting/polishing of the heads, and a good flowing cat back will make for a fun car to drive....not to mention will beat almost anything on the road...lol

Cronic3rd

thirdgen reasource sells headers for the swap.

My whole argument agianst the ls1 is all about cost. Fot the same $ you get more hp from a Gen1. But I will agree that the ls1 is a better motor overall.

lavamadness

For me, I'd like 400-500hp. If could get confortably in the range with an LS1 without too much additional cost, it looks like it'd be worth doing. Exhaust I have to buy new either way. Probably new intake either way. Replacing the heads I think would be the one step that would make it lose a lot of it's appeal.

unknown_host

iTrader: (1)

Most LS1 cars make closer to 300 rwhp on the dyno in stock form. 325 rwhp is usually the 01/02 M6 cars. Here are some cons for an LS1 swap:
Time consuming
Money intensive
Less parts available that cost more $$$

FLYNLOW92rs

iTrader: (53)

Think of it this way....

$1,473.52 - Cost of gas for 15,000 miles at 17mpg
$1,043.75 - Cost of gas for 15,000 miles at 24mpg
--------------
$429.77 - Savings in one year
(x) 5
---------------
$2,148.85 - Total savings over 5 years.....


You spend more on the LS1, but if you calculate how much you will save in gas over the long haul, you can actually end up spending the same amount of money.....

This of course is assuming you are driving 15,000 miles a year and the average difference between gas mileage is 7mpg.....

Just something to think about if you plan on keeping the car for awhile.....

Cronic3rd

Yeah but money 5 years from now isn't even clost to money now. And most people that have project 3rd gens drive them alot less than 15,000 a year...

KYL98

Actually they tend to make more after they have some miles on them.....my Dads 99 T/A is making 313hp at the wheels with 55k miles on it. Only mod is a Hurst shifter...lol The LS1 is the best motor to come out of GM's stall I think.......

25THRSS

LS1's make so much hp because they already come with good parts from the factory. You put a good set of heads and a descent cam in a gen 1 sbc and you'll have a ****load of power too. Is it worth all the trouble? Hell no it's not. It's a crapload of work and custom this and that that when it boils down to it, you should have just stuck with what third gens were designed with in the first place. A gen 1 block. Put some good heads on it and a descent cam and you will do a lot of LS1 stomping.

89 Iroc Z

25THRSS,
I disagree; LS1’s make more power because it is a better engine design. The Gen I SBC is 50 years old. If you did a real side by side comparison of a LS1 and a gen I SBC you will see why a lot of guys are ditching there gen I SBC for LS1’s. You can make insane power levels and keep the engine fully streetable and get great gas mileage.

KYL98

What "trouble"?? You can buy the motor mounts now from Thirdgen Resource....and other than some various wiring, its no harder than a Gen I sbc. The LS1 will make more power than ANY gen I sbc given the same mods.....yes they are a little more expensive right now, but that's only because not enough people are interested or doing the swaps/fix-up's right now. He's only talking about 400-500hp....that is EASILY attainable with the LS1....a good intake and exhaust should be 400 fly hp easily......

unknown_host

iTrader: (1)

25thRSS, I agree.

89 Iroc Z,
How is it a better engine design?

LS1's make more power because they have 18* heads, decent compression and a roller cam from the factory. Put a set of 18* heads and a roller cam in a small block chevy and what do you have? I will tell you that a friend of mine with a 57 chevy just built a gen 1 small block 400 for his car. It has the GM high port 18* heads and a roller cam, and made 730 horsepower NATURALLY ASPIRATED, all motor.

TexasLT1

You're forgetting he said he wants good gas mileage. That simply isn't going to happen with an engine like you suggest. For the kind of gas mileage he wants, he's either going to have to go LS1 or build a milder engine.

Guest

LS1 heads arent 18 degree.

FLYNLOW92rs

iTrader: (53)

I think that this the main point of the LS1

You make large amounts of power with a small block, and your gas mileage is gonna go straight downhill along with your chance of passing emissions.......

25THRSS

Not if you have efi and it is tuned right. Also, if you think those LS1 guys with major mods like heads/cam, etc are getting great gas mileage, think again. Ive got one, I should know.

KYL98

My brother has one also.....he has fully cnc ported/polished, along with the Thunder 220 cam. It has Hooker LT's with the off road Ypipe(with high flow cats on it) and FLowmaster 3in exhaust. He pulls down almost 20mpg.....if not more....plus, he is emissions legal

unknown_host

iTrader: (1)

Sorry 15 degree. So put a set of 15 or 14 degree cylinder heads on a gen 1 small block chevy and a roller cam and see what happens...

scottland

the cost just doesn't justify the price. you could buy used 350 shortblock for 100-150 bucks, get a set of AFR heads, and a moderate cam, throw a holly steath ram, or LT1 EFI system on it, and volia, 20ish mpg, and 450hp. and the bill will still probably be less than an LS1 swap.

and as for this

400hp from an LS1 would cost about $500 or so.....just put a complete exhaust on it....and it would make 400hp at the crank, more if you put a good intake on it. Let's not forget about the weight savings either.....that always allows for a faster car, correct? Look at those ****ty Hondas....weigh 1800lbs with 300hp and go 9's......I would go with the LS1 anyday. You could get 500hp out of an LS1 without even opening the motor up.......

last time i checked headers and exhaust won't produce 50-60 more horsepower. get a clue. maybe 20 if your lucky.


Hondas don't weight 1800lbs, and show me a LS1 that makes 500hp, without touching the heads, or the vavletrain.

Don't make SH** up please, ignorence is annoying.

the LS1 is an awsome motor, if money isn't an option, its worth the swap. but for those on a smaller budget, stick with a GEN I small block.

wm_sorg

The LS1 heads are 15 degree. Right from the factory they flow better most aftermarket heads available for the old SBC design.

The internals are lighter tighter and stronger. The factory redline is around 6200. With cam and springs 6300 - 6400 is common with stock bottom end.

Fuel management and ignition are light years ahead of the SBC.

Parts and mods are readily available and prices are in line with old SBC products. In fact the LS1 engine is the swap of choice in many other types of cars. The LS1 can produce 450-500 HP pass emissions and can easily average 22 MPG for mixed driving.

The cost is well worth it in my opinion.

tamatt27

How would the SDPC Vortec TPI stack up against an LS1 in the terms mentioned? i.e power, reliability, and gas mileage

Guest

Someone local has the Vortec setup, with a cam of course. I'd rather have an LS1, especially when you consider the potential.

KYL98

Who said anything about making something up???? I suppose youre the expert on the LS1 and Hondas????? Well tell me then....how are "stock" LS1 camaros and firebirds putting 330hp-340hp to the GROUND???? If you dont beleive me, take a trip to the dyno or dragstrip...even LS1.com. Furthermore, I dont beleive I was talking to you when I answered this post. I think 330hp @ the wheels is over or close to 400hp at the flywheel.....add some good l/t headers, maybe 40hp to be conservative, take off the cats add the off road Ypipe, another 20....add an AFPR and do some tuning.....EASILY 500hp at the flywheel. You might want to double check **** before you go calling somebody ignorant.....the Gen I wouldnt be able to touch the LS1's mileage capabilities...not to mention emissions etc......

KYL98

By the way, its ignorance....not ignorence.....just food for thought.....:lala:

25THRSS

First off the average stock dyno is nowhere near 340 rwhp. Not even close! It's usually around 300-310 stock. Second, if you had actually done any work to an LS1, you would also know that an afpr is not something done to one, because they have no return fuel line. Now you might want to double check "****" before you go spouting off things you obviously have no idea about. 500 hp with exhaust and tuning, bwhahahaha. That's about 425 rwhp with a manual tranny. It would take heads/cam to achieve those #'s. Don't even try to say I have no idea what I am talking about, because I've got an LS1 sitting in the driveway right now currently with bolt ons and head/cam swap, etc. I am a camaro man, not an LS1 man and I respect the LS1 a hell of a lot, but the gen 1 sbc can make power and pass emmisions just as well as an LS1 when done right. One very important fact, I have come all too well to know, is that you will pay roughly almost 3 times the price for mods for an LS1 than you would the gen 1 sbc!

KYL98

Ok then First, I will admit that I didnt know about the AFPR thing....but I have seen with my own eyes a STOCK T/A put down 330hp @ the wheels.....the car is a 2000 T/a auto with 53Kmiles...stock complete to the air filter. Not too long ago they had a 01 SS on Car and Driver TV put down 325hp and it was brand new....from what Ive heard they tend to produce more power as they loosen up some and get broken in. Second, I apologize for being childish....just dont like being called ignorant by somebody that cant spell it......BUT I am man enough to admit when Im wrong.....

By the way 25th, what cam are you running? Ever heard the Thunder220 cam?? or the B1?

25THRSS

330 rwhp on a stock ls1, especially an auto, is VERY hard to believe. There had to have been something done to it because those kind of #'s are just unheard of stock, especially with an auto. BTW, I am running the Thunder Racing 224/224 cam with about .564 lift.

KYL98

Its been about two months ago....the guy came into my shop for some tranny work.... It sounded very stock, he said it was bone stock....was just having the fluid changed to Royal Purple. I saw the car on the lift...all emissions stuff...stock muffler etc. No signs of aftermarket stuff. It had the stock intake also. He had just got the car from his dad(who bought it brand new) and wanted to see what it would do. The dyno is right next to my shop so we went over......sure enough, 330hp at the wheels. Now I cant swear that he didnt do anything to it.....but he said it was completely stock because the guy asked him about those numbers. I wouldnt have believed it if I didnt see it with my own eyes. If he comes in again...Ill ask about it....

unknown_host

iTrader: (1)

I'm glad you are on these boards. I am sick and tired of people who spout things off like they are facts because they read them on message boards. 90% of people in this post have probably never even worked on/driven an LS1 car...

25THRSS

The LS1 has it's advantages and it's disadvantages, but when it comes down to it I see absolutely no reason to ditch a perfectly good 350 or larger ci sbc. It's absurb how many people think that the LS1 will *** rape any sbc out there and do it with passing emmisions with flying colors. THE SBC HAS BEEN AROUND FOR OVER 55 YEARS. There was a reason it took so long for gm to come out with another one. Because it is a great design! One thing I do like about the LS1 though is how easy it is to do a cam swap since the lifters are held in place by the plastic retainer you don't have to remove the intake manifold, but ofcourse it is ofset by the cam costing nearly 3 times what a gen 1 cam costs. I also love the way they designed the gaskets. It is real nice not having to scrape gasket **** off. I spent a total of probably in the neighborhood of $1,000 for the entire exhaust system for my third gen, and I feel that I bought some of the best compents made. I also spent over $1,300 on just the headers and y pipe for my LS1, that is not including the cats or catback or anything. The intake manifold cost over $400, compared to less than $200 for a gen 1 sbc. I could go on and on, but you get my drift. It is just plain not worth it!

EDIT: I just wanted to say the gen 1 sounds way better than any LS1 out there!
EDIT#2: I was just thinking about how you can't use any other headers besides the stock LS1 exhaust manifolds on a third gen, and i guess the edelbrock shorties, but I'm not positive on that. But why would you put an engine in that you want to make so fast if you can't even put a descent exhaust behind it?

KYL98

Excellent points....can't argue with that. I'll admit I'm no expert when it comes to the LS1. I have driven an LS1 powered T/A many times, but never physically worked on one(yet). From now on, if I'm not 100% sure about something, I'll keep my mouth shut.

CrazyHawaiian

I'm with 25THRSS on this one. Do the LS1 swap if you want a LS1. Stick with the gen 1 block if you just care about power. The LS1 swap is cool and all, but the gen 1 block can get the job done. Aside from the cost of the LS1, you also have to factor the cost of the swap. If you are a DIY guy then it might not cost that much to swap in a LS1, just your time. If you plan to pay someone to install it, or you plan to mod it beyond stock, then you will probably get more bang for the buck with the gen 1 block. Plus the cool thing about building the gen 1 is you can build it for a specific application. There are alot of intake/heads/cam choices out there. The LS1 is a badass motor, no doubt, but what if you plan to push boost/joice later? Or what if you want a different powerband? Those types of mods later on will raise the cost of the project even more (seeing that mods are more expensive for the LS1). If you do a search there is a post entitled '500hp 22mpg' or somewhere along those lines by Kingalt0n. In this post he gives a detailed description of reaching 500hp and 22mpg using the gen 1 block. I think you should read that post because of the 22mpg part. Its not impossible to get good mileage with a EFI gen 1 setup. It just needs to be tuned right. Bolt in chips wont do the job, you'll need specific tuning.

Guest

I'm going to ask you guys once to behave.

As for the LS1, check this out:

http://www.ls1tech.com/threads/showf...5&o=31&fpart=1

Seriously doubt he needed to burn $$$$ for the block and heads (though its undoubtedly more reliable that way), but the idea remains the same. Full weight car, some boost, not really significantly bored/stroked...

scottland

you could do the same thing with a GEN I small block.

hes got C5R heads, and a C5R block

with the same money he spent on C5R components,

Plus hes running some insane compression with C5R's 3X'cc chambers

you could buy a nascar spec motor, lower the compression ratio, and throw a blower on there, and make comparable numbers. he never mentioned what fuel octane hes using. and that motor is really significant, its a full out race motor, so bad example.

Guest

Show me one.

scottland

Must I.....


https://www.thirdgen.org/techbb2/sho...hreadid=200529

https://www.thirdgen.org/techbb2/sho...hreadid=196283

Guest

Not sure what thats supposed to prove... twin turbos and 427CI. Try again.

25THRSS

I guarantee you he's got close to $30,000 in that motor. Factor in the insane price of the c5r block, the heads, the machine work, the crank, etc, plus the power adder, that is just a rediculous amount of money to spend on an engine. you could do that with a gen 1 block for alteast half the price and still have an engine that was actually designed to be in the car.

25THRSS

That gen 1 block has over 500 more hp than that LS1, point well proven.

Guest

I guess I'm done arguing with experts then with 14 second cars.