Don't buy that LS engine
Discussion
For those of you who are considering changing from the SBC to an LS engine, an option is becoming available to use the LS heads on the SBC style block; retaining the crankshaft, starter, clutch, bellhousing etc. choice of carburator or fuel injection, distributor or 24 tooth crank trigger. World Products,( Bill Mitchell ) and Comp Cams have developed a block and cam set up to use stock LS pistons and connecting rods on the original crank, a block with the water jackets that align with the LS heads and a cam which has the added fuel pump lobe and distributor drive gear to make it all work. I believe you would save a lot of money vs. all the changes to go with the LS, with a 70 lb. weight difference. I hope this is helpful to those considering the change over.
Jeez Kyle...........not sleeping well?..... posting at that time!
I think its an option aimed at the US car market where SBC was the original fit but the LS heads/alloy SBC block give up-to date options too. Maybe the rules applied to a complete change of engine become diluted if an original design block is utilized. In other words, LS motor in a SBC shell.
Not dissimilar to our SVA stuff really?
Quite a few posts on 'speedtalk' about it.
Enjoy a lye-in Kyle.
I think its an option aimed at the US car market where SBC was the original fit but the LS heads/alloy SBC block give up-to date options too. Maybe the rules applied to a complete change of engine become diluted if an original design block is utilized. In other words, LS motor in a SBC shell.
Not dissimilar to our SVA stuff really?
Quite a few posts on 'speedtalk' about it.
Enjoy a lye-in Kyle.
738 driver said:
Jeez Kyle...........not sleeping well?..... posting at that time!
I think its an option aimed at the US car market where SBC was the original fit but the LS heads/alloy SBC block give up-to date options too. Maybe the rules applied to a complete change of engine become diluted if an original design block is utilized. In other words, LS motor in a SBC shell.
Not dissimilar to our SVA stuff really?
Quite a few posts on 'speedtalk' about it.
Enjoy a lye-in Kyle.
not feelin too hot boys, man flu. I think its an option aimed at the US car market where SBC was the original fit but the LS heads/alloy SBC block give up-to date options too. Maybe the rules applied to a complete change of engine become diluted if an original design block is utilized. In other words, LS motor in a SBC shell.
Not dissimilar to our SVA stuff really?
Quite a few posts on 'speedtalk' about it.
Enjoy a lye-in Kyle.
Seems like a bit of a waste of time to me!
738 driver said:
Yeah that flu always is a big waste of time!!!!
When is your motor back from the bodyshop?
Im not sure, it was sprayed in the blue on Friday so i think the orange goes on Monday then ive got to go and look at the positioning of the decals before they are laquered over.When is your motor back from the bodyshop?
The bodyshop has spent a lot of time on the preparation, we have also done a few other little modifications.
I cant wait Dave, i will fire you some pics over when she is finished. My LS/G50 should be here prior to Christmas so i shall crack on with that and have it running asap.
What stage you at with your car/engine.
I appeciate the original input, always great to hear about diiferent ways to do stuff. But if you only use the LS heads you miss out on a bunch of really good tech. Like cross drilled 6 bolt mains and a completly new crankshaft main seal the list goes on. I think this option was pursuded by World to fill a certain rule requrment for a racing class. Lee
ROWDYRENAULT said:
I appeciate the original input, always great to hear about diiferent ways to do stuff. But if you only use the LS heads you miss out on a bunch of really good tech. Like cross drilled 6 bolt mains and a completly new crankshaft main seal the list goes on. I think this option was pursuded by World to fill a certain rule requrment for a racing class. Lee
could be lee! also dont the LS7 heads flow ALOT better than the older SBC stuff??Chris.
Boosted LS1 said:
IIrc lsx has different bore spacing to sbc which if that's the case means they have almost designed an lsx block and then given it sbc features. To go backwards like that must be to comply with racing rules.
boosted dosen't the Warhwak block come with SBC mounts?? would that not bee a better bet (and you can takethe to 481ci)??Chris.
There where two questions one do the LS series heads flow better than the SBC. The answer to that is yes when you compare stock heads to stock heads. Certainly after market SBC heads are a far cry from the stock setup but notice that every time the aftermarket or Chevy changed the stock heads the first thing they do is stand the valves up straighter in the heads to try to get better flow. The other commen made was that the bore spacing is different between the SBC and the LS I pretty sure that the bore spacing is the same.In fact that is about the only thing the two motors have in common. Lee
ROWDYRENAULT said:
The other commen made was that the bore spacing is different between the SBC and the LS I pretty sure that the bore spacing is the same.In fact that is about the only thing the two motors have in common. Lee
The big end shells are common. Reason I mentioned the bore spacing was that when the lsx first came along I had a brainwave to fit the lsx top end (heads and intake) onto the sbc and for some reason I didn't do it. I know the lsx has smaller bores and I think this allowed them to locate them closer to shorten the motor. I could be wrong as it's a long time ago when I was thinking about it.Boasted: Your statement made me go back and read the book which is a good thing from time to time. The bore spacing is the same 4.4 inchs. The overall length is SBC 553.3 MM LS 519 MM block width is SBC 434.6 MM, LS is 460 MM. Block deck height SBC is 9.025 inchs LS is 9.240. Rod length is SBC 5.7 inchs LS is 6.098 inchs. SBC weighs 531 LBS a LS weighs 430 lbs. These weights are quoted for an LS1 VS A lt1 SBC which comes stock with alloy heads. So for those of us that aren't engine builders but have a more than superficail intrest I would point to the lighter weight, greater deck height to allow for greater capacity, longer rods for greater bore to stroke ratios and shorter length as prime advantages to the LS. Here in the States a slight cost advantage to the SBC in part prices, but if you are talking about a full up alloy block aftermarket heads ect SBC the advantage is soon gone. As far as the great weight advantage of say the Audi 4.2 v8 I would be very suprised if that exceeds 80 lbs and its still 4.2 liters vs ???? 6 liters at least. As an example my 6.3 liter LS1 makes 565 HP 572 foot lbs. Let me say these are solid conservative numbers done by a very professional shop with no axe to grind on the numbers. The torque curve is very flat I use a G50-03 with a 3.40 rear end and .96 in 4th and .68 in 5th. This combination gets 25 mpg, remember thats a U.S. gallon which I think is a bit smaller and the car is very quick, in 5th at anything over 65 miles per hour I would down shift only if I really was trying to pass in a space that I should not. O.K guys that is as unbaised as I can put the argument for the LS without really going overboard and talking about the 6 bolt mains no dizzy, yada yada yada. Lee
Gentlemen, If you have seen the list of components and the prices involved in replacing the SBC with an LS7 engine you are probably a bit hesitant to undergo the change. Now if you were able to replace the engine alone, with a 629 hp. carburated 427 cubic inch SBC that has LS heads you might have a keener interest. That is the reason I brought this up. This setup is around 70 lbs. heavier, utilizes a 6.125" length SBC connecting rod, not an LS as I first stated. It has provisions for a dry sump oiling system. The reason it is being marketed is for this type of engine upgrade, maintaining most of the current setup. Its called the Mohawk LS, details are being worked out as to how it will be offered: short block, complete engine etc, thought you might want to know.
Alb. GTR said:
Gentlemen, If you have seen the list of components and the prices involved in replacing the SBC with an LS7 engine you are probably a bit hesitant to undergo the change. Now if you were able to replace the engine alone, with a 629 hp. carburated 427 cubic inch SBC that has LS heads you might have a keener interest. That is the reason I brought this up. This setup is around 70 lbs. heavier, utilizes a 6.125" length SBC connecting rod, not an LS as I first stated. It has provisions for a dry sump oiling system. The reason it is being marketed is for this type of engine upgrade, maintaining most of the current setup. Its called the Mohawk LS, details are being worked out as to how it will be offered: short block, complete engine etc, thought you might want to know.
no thanks!! what the hell is the point of going back to a carb with SBC bearing tolerances?? My SBC with an Ali block is 70lbs lighter but its still a SBC.Gassing Station | Ultima | Top of Page | What's New | My Stuff