Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (http://www.hotrodders.com/forum/)
-   Engine (http://www.hotrodders.com/forum/engine/)
-   -   ls1 vs sbc 350 (http://www.hotrodders.com/forum/ls1-vs-sbc-350-a-226986.html)

munchigan 12-09-2012 10:07 AM

ls1 vs sbc 350
 
Ok i know this topic has been beat to death and i know the ls engines are far more advanced but is all the work to fit a ls and wiring, plumbing, exc worth the benefits of the ls I would be using a t56 trans also so that means more work also is there any way i could get good drivable car out of my 80 z28 with a 350/4speed. A ls would be awesome though what all problems am I looking at if i bought a used ls1 complete with wiring and a t56 im doing a ground up restore and now would be the time to do the ls swap but im also ready to get this thing on the road and this would put me farther behind any opinions would be awesome

hcompton 12-09-2012 10:20 AM

What is your goal hp or good mpg.

You can install ls motor with front mount engine plate which you can make at home if you got the tools. Also make out of card board and get cut at local shop. This can really cut the cost down but go to research to make sure its proper for your application.

If you run efi be sure to buy a complete engine kit. With engine wireing harness and all asseories on the engine and computer attached to the harness.

Now if all you have is a motor and trans i would use a carb setup and make some serious power out of the motor. Since the efi isnt the limiting factor.

vinniekq2 12-09-2012 10:30 AM

what makes the LS engine superior?better heads? fuel injection?

Guess what,better heads and fuel injection is available for gen 1 engines

now you have to choose,update an old engine with modern parts or buy a modern a modern engine that has modern parts? we still burn gasoline in the engines,pistons and valves are the same in both engines.

biggest problem is cost

hcompton 12-09-2012 10:38 AM

Quote:

Originally Posted by vinniekq2 (Post 1620845)
what makes the LS engine superior?better heads? fuel injection?

Guess what,better heads and fuel injection is available for gen 1 engines

now you have to choose,update an old engine with modern parts or buy a modern a modern engine that has modern parts? we still burn gasoline in the engines,pistons and valves are the same in both engines.

biggest problem is cost

Much better heads. Stock ls heads are better than 18degree heads for gen one. So with large bore short stroke LS motor you cna make a ton of power with valves bigger than 2.02/2.08 inch that is pretty much max for the gen one bores.

Even with smaller bores the ports are right on top fo the valves and give great air flow more than can be found in most if not all gen one heads. Certainly all 23 degree heads.

But yes you can make a ton of power with a gen one engine. I have gen one in my car not an ls motor. Maybe one day but the cost has not made me decide to move yet.

vinniekq2 12-09-2012 10:53 AM

hcompton

sounds like you actually agree with me.If we build ,as an example, a 500 HP LS or gen 1,then as long as the heads are both capable of correct flow and velocity with decent combustion chamber shape,both use a roller cam and fuel injection with correct A/F ratios and crank fired ignition to compare to modern LS ignition,,,,,

the performance should be the same or very very close?

what the real issues are:
can I make a gen 1 with a carb and flat tappet cam and distributor perform anything at all like a modern engine?

hcompton 12-09-2012 11:30 AM

Quote:

Originally Posted by vinniekq2 (Post 1620855)
hcompton

sounds like you actually agree with me.If we build ,as an example, a 500 HP LS or gen 1,then as long as the heads are both capable of correct flow and velocity with decent combustion chamber shape,both use a roller cam and fuel injection with correct A/F ratios and crank fired ignition to compare to modern LS ignition,,,,,

the performance should be the same or very very close?

what the real issues are:
can I make a gen 1 with a carb and flat tappet cam and distributor perform anything at all like a modern engine?

The ls motor can be made to breath a little better down low and will make a little more punch in all. But yeah most numbers you cna make with a ls motor can be made with a gen one. And if were talking major hp like 18 degree heads will provide the gen one may be cheaper since a lot of the parts are easy to come buy. And in this case the gen one is almost surely cheaper in 300-400 flavors as well. Since the op alreayd has one installed.

But the ls motor will make 350 hp and use a lot less fuel to do it. Since it can do it with less rpm and more stable cam sizes. Never tried 18 degree heads on that small a hp number not sure how they would perform but all ls heads are no more than 15 degree. I think 12 degree is also out there.

But yes for my money i would build the gen one and forget about it. Now a 6 speed or th700r4 will increase the mpg by leaps and bounds. But both are much larger than stock. my not bolt to stock cross member but worth the effort to make them fit. Th700r4 wpuld be faster at the strip than a manual. Also provide near manual fuel milage with lockup options all setup right.

ap72 12-09-2012 11:58 AM

Quote:

Originally Posted by vinniekq2 (Post 1620855)
what the real issues are:
can I make a gen 1 with a carb and flat tappet cam and distributor perform anything at all like a modern engine?

No you cannot.

And show me a stock 350 long block that can run around 1,000hp. There's a LOT of boosted 5.3L's doing that every weekend.

The heads are a big advantage as is the intake design, as is the electronics, but those are NOT the only advantages. Every aspect has been improved from the oil pump to the valve stem.

gearheadslife 12-09-2012 12:29 PM

Quote:

Originally Posted by ap72 (Post 1620871)
No you cannot.

And show me a stock 350 long block that can run around 1,000hp. There's a LOT of boosted 5.3L's doing that every weekend.

The heads are a big advantage as is the intake design, as is the electronics, but those are NOT the only advantages. Every aspect has been improved from the oil pump to the valve stem.

oh boy, man, they did that crap to gen I's
boosted the .00001% difference in intake tracts aint making any difference..
the computer control is the only + for the ls family.
nothing you can't do to a gen I
most don't as the 5.3's are el cheapo at the moment, that will change with c.a.f.e. ratings on trucks
the love afair with hp in trucks is going to die a fast death real soon.. cause a 180hp engine uses tons less fuel than the 400+ ones in trucks now.. and are not needed with 6 gears other than a penis war bewteen manufactors and this is good, as it'll being the mini me duramax on line.. and bring 40mpg 1/2 tons to market.. killing the gas 5.3/6.0/6.2 it'll be v6 gas or mini me duramax, ford will be boosted v6 gas and their oil burner.,

hcompton 12-09-2012 12:40 PM

If your going for maxed put engine yes ypu can make big power with ls style ehads. But ypu can get good heands for gen 1 engines. 18 degree heads make 800 hp without boost. And yes you canuse under cut valves in them as well as 23 degree heads.

But if you are talking about a 300hp-500hp engine. Gen one and ls will come pretty close to each other but cost for LS is going to be twice as much now there are still benifits but not always worth it in older ride.

CNC BLOCKS NE 12-09-2012 12:59 PM

Its hard for the Gen 1 engine to compete with the LS based engine, With there 12 degree intake valve, Large journal cam, high rocker ratio from the factory. Raise cam tunnel.

23 degree heads don't stand much of a chance!!

On the LS engines I have never cared for the Y-block design as that went out in the early 70's

gearheadslife 12-09-2012 04:54 PM

Quote:

Originally Posted by CNC BLOCKS NE (Post 1620897)
Its hard for the Gen 1 engine to compete with the LS based engine, With there 12 degree intake valve, Large journal cam, high rocker ratio from the factory. Raise cam tunnel.

23 degree heads don't stand much of a chance!!

On the LS engines I have never cared for the Y-block design as that went out in the early 70's

worlds genI block that takes ls top end, kills both

ap72 12-09-2012 04:56 PM

Quote:

Originally Posted by gearheadslife (Post 1620882)
oh boy, man, they did that crap to gen I's
boosted the .00001% difference in intake tracts aint making any difference..
the computer control is the only + for the ls family.
nothing you can't do to a gen I

not even close.

gearheadslife 12-09-2012 05:15 PM

Quote:

Originally Posted by ap72 (Post 1620988)
not even close.

ok..
the ls is an emission move..
boost a ls pops gaskets
the ls engine killed asa, and those where 200 miles runs.. and boom..

munchigan 12-09-2012 06:46 PM

i guess i want mpg rather than hp maby 400 hp but i just want something i can drive. I have had a 2000 z28 and it was good power and mileage and i want that in my 80 z28 i can buy a complete ls1 motor and t56 trans for about 5k and im going to have about 3k in a rebuilt 350 the way i want it .It just seems the ls swap would be alot of work could i get decent mileage out of a 1st gen 350/4speed or is the ls swap not a bad as im thinking

ap72 12-09-2012 07:17 PM

If you only want about 400hp and good mileage do you care if it has less than 8 cylinders?

A boosted 6 cylinder can get you there too. Head work, a cam, blower pulley, and tuning on a supercharger 3800 backed by a T5 can be cobbled together pretty cheaply.

LS engines are great too, just a different idea.


All times are GMT -6. The time now is 11:34 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.