Jump to content

Pushrod engines, why?


Mensan
 Share

Recommended Posts

Originally posted by Mallard:

um...no. GM's best motor has to be the LS series of engines. The LS6/LS2 has as much to more power as the ZR1, and it's still a small block and doesn't cost an arm and a leg.

True, but that was designed over 10 years ago, and we are just now seeing them make a pushrod engine exceed/meet what the LT5 was making back then? :confused:

 

Who knows what would happen if they actually went all out and did it again, what kind of beast it would be. :eek:

Link to comment
Share on other sites

  • Replies 83
  • Created
  • Last Reply

Top Posters In This Topic

Originally posted by BIG SHAFE:

True, but that was designed over 10 years ago, and we are just now seeing them make a pushrod engine exceed/meet what the LT5 was making back then? :confused:

 

Who knows what would happen if they actually went all out and did it again, what kind of beast it would be. :eek:

Don't forget the ZR1 was a high dollar, limited production, best of the best motor. The LS1 and LS2 are engineered to be powerful, plentiful, and cheap to produce.
Link to comment
Share on other sites

Yeah mine pulls all the way to the 7k redline...STOCK.

 

Some things that I have noticed about this thread:

 

There is alot of misinformation. My car DOES utilize blockoff plates for one set of ports to gain low end torque. There IS electronic valve timing for 3+ valve heads. Also, if your argument is torque, take a look at the 427 SOHC engine, and why it never made it to production cars. That engine fucking owned all. Look at the numbers that Hensler made on the big bore stroker engine he built for Andy. The car is only 324ci, but made plenty of torque AND HP. Compare apples to oranges by comparing similar RPM ranges and cubic inches. I think that takes care of all the defending arguments other than cost. That is the only advantage I can see from working on a pushrod engine. Possibly the availability of parts. I would like to hear from the people who have owned and worked on BOTH types of engines (as I have).

 

The only reason I started this thread was in response to N20birds rotary thread.

Link to comment
Share on other sites

Originally posted by Tinman:

Don't forget the ZR1 was a high dollar, limited production, best of the best motor. The LS1 and LS2 are engineered to be powerful, plentiful, and cheap to produce.

True, but some people were paying well over MSRP just get one, so the market is definitely out there.

;)

Link to comment
Share on other sites

Guest Ponyfreak

All I will run anymore is DOHC engines. I have never had a stock car that ran 13 second 1/4 miles and could still get 32 mph on a 1000 mile trip to and from carlisle penn.

 

Do not worry TinMan. Your car runs about like mine does right now. That will be something that will change one day when I get 20 psi of huff power on my pussy DOHC.

 

Just a little tidbit of info, there are a couple guys out there now making 500rwhp and 500ftlbs torque n/a with modded 5.4DOHC's. The only reason why the 281's do not make that much torque is due to displacement. YOu cut 65ci off of those precious LS's and see how much hp and torque they make.

Link to comment
Share on other sites

Originally posted by Mensan:

I think that takes care of all the defending arguments other than cost. That is the only advantage I can see from working on a pushrod engine. Possibly the availability of parts. I would like to hear from the people who have owned and worked on BOTH types of engines (as I have).

what about packaging and weight?

 

I have owned and driven both types of engines. Although I've never experienced a DOHC V8 in a proper sports car, only a stock Mark VIII. But I have driven a 2004 Viper, C6 Vette, CTS-V, Mark VIII, 350Z, 240Z, and a bunch of other FWD cars of both configurations. I'd like to get behind the wheel of a DOHC V8 sports car...I'll let ya know when I find one.

Link to comment
Share on other sites

Originally posted by Ponyfreak.:

All I will run anymore is DOHC engines. I have never had a stock car that ran 13 second 1/4 miles and could still get 32 mph on a 1000 mile trip to and from carlisle penn.

01 Trans Am: 32 mpg from New Jersey to Cleveland. Ran low 13's with a whole bunch of suspension mods that hurt drag times.
Link to comment
Share on other sites

Guest Ponyfreak

FYI Couple stroked/bored 4.6's out thre making high 400HP and 800 rwhp with 10psi of boost.

 

John Mihovetz is running 6.X @ 19X mph with 4.6 281 DOHC

Link to comment
Share on other sites

Originally posted by Mallard:

what about packaging and weight?

 

I'd like to get behind the wheel of a DOHC V8 sports car...I'll let ya know when I find one.

I will let you drive mine. Shouldn't be long now. I got to drive a Mark VIII with a cobra intake and a blower. It made an additional 100+ HP to the wheels at just under 7 psi. It stil didn't make as much power (OR TORQUE) as my car does currently, and mine is untuned and running poorly. Ask someone familiar with my project what kind of power I will be looking at, and how the car should feel.
Link to comment
Share on other sites

Originally posted by Ponyfreak.:

All I will run anymore is DOHC engines. I have never had a stock car that ran 13 second 1/4 miles and could still get 32 mph on a 1000 mile trip to and from carlisle penn.

 

13.24@106.5 stock, 29.8 mpg highway, with an A4 smile.gif
Link to comment
Share on other sites

Originally posted by Mensan:

The car is only 324ci, but made plenty of torque AND HP. Compare apples to oranges by comparing similar RPM ranges and cubic inches.

Who cares about cubic inches, when that 4V motor is physically a FAR larger engine than an LS1??

 

Why are people stuck on "it makes x HP per cubic inch??" It's the ACTUAL PHYSICAL SIZE OF THE MOTOR THAT COUNTS!!!

Link to comment
Share on other sites

Originally posted by GAS,GRASS,OR ASS:

one word sums up why pushrods are greater than a cammer. HEMI. every top fuel/funny car has one...

so do a lot of hondas... tongue.gif

 

http://e.1asphost.com/simplyfast/Engines/B16A%20Head/Pent-Roof1.jpg

Link to comment
Share on other sites

first, gas mileage, james cobra went 10.80's on a COMPLETELY stock LONG block, 2 1/2 in exhaust and still got 22 mpg with his t-45

i would take a DOHC motor anyday over my 5.0.

one of our customers 305's made 408 rwhp and like 375 tq

andy's 324 450+ hp and 400 tq

shitty things. stock rods and pistons suck balls. run heads studs and blew a head gasket, motor has to come out, doing cam swap, it's easier to pull the motor to do it. it's hard to even get the valve covers off

but the 5.0's do sound a hell of a lot better

Link to comment
Share on other sites

Originally posted by recklessOP:

so do a lot of hondas... tongue.gif

a honda is not a pushrod hemi quote it right or don't waste my time.

 

cam in block is simpler more cost efficent design in a v8 or v6

 

ohv one cam short timing chain plus pushrods

 

ohc two or more cams plus a long ass chain or belt

 

total reciprocating mass ends up working out about the same.

 

 

now in a inline style 4'6'8 cylinder ohc is nice all you have to do is pop off the valve cover and the belt to change the cam(s). its all about packaging you have to drop the k-member in a mustang to put headers on it makes it an all day job in an f-body or a gto its tight but you can do the swap in about half the time if you have help. both styles of engines have merits and flaws. and remember with enough money anything can go fast and it cost far more to go fast with a cammer than it does with pushrods. it costs over 1000 dollars to do cams in a ford for thst money you can put a cam AND heads on a pushrod motor. one > than the other probably not

 

OHV cheaper than OHC proven fact.

Link to comment
Share on other sites

Guest Ranger_Man
Originally posted by recklessOP:

[QB] so do a lot of hondas...

and pretty much every other 4 valve per cylinder engine ever made.

 

hemi just does not mean as much as it used to. people really should just start calling them overpriced dodges.

 

oh and my thoughts?

 

dock>sock>knock

 

thats dohc>sohc>nohc (no over head cam) for the 98% of CR members that wouldnt understand the funny above.

Link to comment
Share on other sites

Originally posted by Mensan:

I will let you drive mine. Shouldn't be long now. I got to drive a Mark VIII with a cobra intake and a blower. It made an additional 100+ HP to the wheels at just under 7 psi. It stil didn't make as much power (OR TORQUE) as my car does currently, and mine is untuned and running poorly. Ask someone familiar with my project what kind of power I will be looking at, and how the car should feel.

Well I may have to take you up on that when I get home in October. I'll probably just take a ride in it though as it's not my car. Everything I get to beat on is at work so it's not really someones personal car.

 

As far as this debate:

 

I'm not denying that DOHC motors can make a lot of power, especially with boost. (also 10psi tells me nothing without knowing the size of the turbo)

 

I think DOHC is better for racing, high rpm applications, but so far nobody seems to know why. Everyone keeps pointing and saying "look at this or that car." All I wanted to hear were the reasons: Variable cam timing, better intake runners because you don't have to worry about a pushrod in the way of the best path, etc.

 

However, I don't think the Ford Mod DOHC motors are good because of size/packaging, valvetrain inertia, and cost. I like the pushrods because a small block can be put in any engine bay, mods are ~cheap, they make great power, and the LSx is probably the most technologically advanced OHV engines in the world.

 

Matt- I don't care if the cams are hollow or not,there are 4 of them and they still weigh more then the one cam in an LS2.

Link to comment
Share on other sites

Originally posted by Mallard:

I think DOHC is better for racing, high rpm applications, but so far nobody seems to know why.

because the valve springs in an OHV motor have to control a set of pushrods too. you tend to get push rod flex and valve float at high rpm...

 

i will admit the ford V8 is far from perfect. a DOHC V8 doesn't need to be that big...

Link to comment
Share on other sites

Originally posted by GAS,GRASS,OR ASS:

one word sums up why pushrods are greater than a cammer. HEMI. every top fuel/funny car has one with 16 pushrods. show me an over head cam car that can produce wheelspin at over 300mph. and we can continue this argument

Banning a technology through the rulebook != the legal tech being superior. ;)
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share


×
×
  • Create New...