overhead cam GM engines.

[Pablo]

OHC engines are a waste of time.

\If you have as stated goal of making the largest engine with the most moving parts then OHC is the way to go.

Otherwise, it's blatantly obvious these days that the pushrod engine (i.e. the LSX) is vastly superior.

Show me one ohc engine that can match the LSX in performance potential, price, reliability, efficiency, and packaging.

For some reason people seem to think that added complexity is synonymous with technological progress.

I don't understand that.

If you built an engine with 3 moving parts and it had the same performance and efficiency numbers as a BMW dohc engine you would still have people raising their nose and saying that the BMW engine was far superior.

Also, what does hp per liter matter? If I built an 8 liter engine that put out the same power as a 4.6, got the same fuel mileage, had the same reliability... what difference does it make? What does having less displacement internally give you if it doesn't give you better efficiency? Seems almost like kind of a dogmatic belief that HP per liter actually accounts for something in the space time continuum

 

[Turbo6Smackdown]

Yea, youre right. just lookin at some of the pros and cons. I guess what im goin for is an engine thats easy to work on, easy to find parts for, reliable, and QUICK throttle response. I was just going over which would be a better choice. Find a late model F body, that threw a rod clear through the block, for like 2 grand, and throw in an LT5, which has dual overhead cams and an aluminum block (I'm thinking HUGE throttle response, due to the light weight, and the elimination of lifters, pushrods and rockers) or just go with an f body that already has an LS1 in it, and go.

 

[Turbo6Smackdown]

OHC engines are a waste of time.

\If you have as stated goal of making the largest engine with the most moving parts then OHC is the way to go.

Otherwise, it's blatantly obvious these days that the pushrod engine (i.e. the LSX) is vastly superior.

Show me one ohc engine that can match the LSX in performance potential, price, reliability, efficiency, and packaging.

For some reason people seem to think that added complexity is synonymous with technological progress.

I don't understand that.

If you built an engine with 3 moving parts and it had the same performance and efficiency numbers as a BMW dohc engine you would still have people raising their nose and saying that the BMW engine was far superior.

I agree there. but show you an OHC car that can match the LSx engines in performance and efficiency? 1990-92 ZR1.

 

[Pablo]

Yea, youre right. just lookin at some of the pros and cons. I guess what im goin for is an engine thats easy to work on, easy to find parts for, reliable, and QUICK throttle response. I was just going over which would be a better choice. Find a late model F body, that threw a rod clear through the block, for like 2 grand, and throw in an LT5, which has dual overhead cams and an aluminum block (I'm thinking HUGE throttle response, due to the light weight, and the elimination of lifters, pushrods and rockers) or just go with an f body that already has an LS1 in it, and go.

How do you think those overhead cams are spun? There is way more rotating mass in a dohc V8, the chains or belts that spin those cams and those cam sprockets are not weightless or without friction.

An LT5 will only cost you probably 20 grand and if IIRC only produce 340 hp.

If you want snappy throttle response take a look at something with a light rotating assembly. Lsx engines have awesome throttle response

 

[Pablo]

lt5 only cost many times more. I could remember seeing lt5 crate engines for sale many moons ago for 17,000 a pop.

and I just looked it up. the most HP they ever made was 405 for one year only.

 

[UNGN]

My Buddies with ZR-1's tell me they run 150 mph in the standing mile stock. (My 502 powered Aerobrick runs 160)

'06-up Z06 runs 165+ mph in the standing mile stock.

So in Stock form, there is no comparison.

With more cubes, you can make an LT5 make 550 RWHP NA by making it scream, but you'll easily have $20K+ in the motor

I would rather spend the money on Twin Turbos than DOHC's, 550 HP would be 91 octane numbers with a TT V-8.

 

[chopped39]

Thats why gm is talking about making a supercharged dohc engine that will produce 780hp haibeck racings zr1 makes a boatload of horsepower. the only reason gm stopped the lt5 is obd2 they would have to redesign the engine.Look at the eletronics and fuel systems gm used for the lt5 .Use todays eletronics and fuel systems can you say 500hp .Im not saying that because i own one. Dohc and variable valve timing control are the wave of the future. When perfected the eletronic lifter/valve controller will rule all. no cam no chain no tensioner no pusrod. just solenoids for each valve Its coming.

 

[Turbo6Smackdown]

wow, where do i get me one of those lol. Though, the king of the production engines is the new LS7. THAT engine is just stupid. Though I dont have 13 grand either lol. I suppose the LS1 is just fine huh. I was just here, seeing if theres anything better. For me, my decision making process works like this. I reference everything I presently know about the subject, and make a decision, then, I search the web, seeing if I can find anything better. Then, when I find something that I think is better, I come here, to you experts, and ask, "which do YOU think is better". And thats how I do it. So pretty much, bustin my assneck, for a rare ohc engine, is a total waste of time and money, and the ls1 can do everything it can for cheaper as well. Thats sort of the answer I was hopin for, as I could walk into any speed shop on the planet, and find a part for an LS1. Ok then, I have my answer lol. Very good, thank you guys. But, if you want to continue on the technical advantages to each, talk away. I like to see what you guys have to say.

 

[chopped39]

Your better off getting an ls1 powered car. Bang for the buck you cant beat them. I have seen ss z28 camaros go through the auction wrecked for 2500.00. there is your whole drivetrain that you can bolt into just about anything.Sorry for going on about the dohc stuff. You are right on with being able to find parts for the ls1. your lt5 breaks down you better own a lathe.you cant even get a water pump without waiting for a couple of days. the lt5 is a pain in the azz to work on also.The ls1 is so simple to work on its funny.If i did not have so much tied up in my buick I would put a 6.0 with a turbo in it.

 

[Turbo6Smackdown]

OH, I didnt even notice you OWNED a ZR1 lol. shows you how much i pay attention while doing this in between sets. (im working out right now.)

 

[dgoodhue]

How do you think those overhead cams are spun? There is way more rotating mass in a dohc V8, the chains or belts that spin those cams and those cam sprockets are not weightless or without friction.

An LT5 will only cost you probably 20 grand and if IIRC only produce 340 hp.

If you want snappy throttle response take a look at something with a light rotating assembly. Lsx engines have awesome throttle response

One of my good friends has a 90 ZR-1, its nothing to write home about in terms of low rpm throtle response. GM even block off 1/2 of the runners below 4000rpm to improve throttle response.

 

[UNGN]

Your better off getting an ls1 powered car. Bang for the buck you cant beat them. I have seen ss z28 camaros go through the auction wrecked for 2500.00. there is your whole drivetrain that you can bolt into just about anything.Sorry for going on about the dohc stuff. You are right on with being able to find parts for the ls1. your lt5 breaks down you better own a lathe.you cant even get a water pump without waiting for a couple of days. the lt5 is a pain in the azz to work on also.The ls1 is so simple to work on its funny.If i did not have so much tied up in my buick I would put a 6.0 with a turbo in it.

One of My ZR-1 friends had his rebuilt 3 times before they got it right. It made a stupid amount of Power when It was right, but we are talking 3 years of smoke screens and Boat loads of money to get there.

 

[turbofish38]

The ZR1 made 375HP in 90 and 91. In 92 it bumped up to 405HP. Than there were the BlackMagic crate motors that made over 500HP. All from a NA 350 cube 8 cylinder. More or less the same numbers made by a 6.0 LS2.

If it was me I'd buy a LS7 crate motor. Plug and play. I hate to do a lot of thinking on my projects. The smoke sets of the smoke detectors in the house.:tongue:

 

[Turbo6Smackdown]

Yea, that LS7 is no joke. Its my favorite motor (well, a newer rendition anyways) outside of the LC2. An all aluminum 427 big block gets my heart racing... Though, I think buicks stage 1 455 may actually surpass that here shortly.