Push rod engines in the 21st century? Really ?

[Greg Myers]

Lookin' at an "Engine Swaps" mag from Carcraft and started thinkn' "You know Chevy's still pushin' push rod engines and Ford has been working with OHC's for quite awhile. What's up with that? Thing is, they both make big power."

Lookin' at the magazine again I was wondering where (what kits?) does one get these modern engines for engine swaps in scale?

[wisdonm]

Ford OHC engines are found in any '96 and newer Mustang kit. Chevy OHC engines can be found in '90-'95 ZR1 Corvette and '39 Wagon Rod kits. Old style Chrysler Hemi OHC engines can be found in the '70 Super Bee Pro Street.

Edited December 17, 2012 by wisdonm

[Guest]

The Revell '99 Chevy Silverado also has the pushrod engine with an automatic behind it.

[johnbuzzed]

The new Revell Challenger kit has a contemporary Hemi, as do the Lindberg Charger cop cars and the Testors Chargers kits; I think this Hemi still has pushrods. I'd like to see some in-scale speed equipment such as headers, blowers and cold-air induction systems for all the contemporary engines- Dodge, Ford and Chevy. Remember when manufacturers would throw in optional parts ?

[Ace-Garageguy]

It all comes down to numbers. Flow-bench numbers, horsepower and torque numbers, volumetric efficiency numbers, and most importantly from a business standpoint, cost-to-develop and cost-to-tool-and-produce numbers.

GM experimented with a DOHC, 4-valve per chamber Corvette V8 engine, the LT-5, available as Brian pointed out in the ZR-1. In the final analysis, the cost to build the thing, the complexity, etc. etc. etc. outweighed the 'cool' and 'exotic' factors as the later LS engines, being only 2-valve per cylinder pushrod engines, delivered equal or better performance at vastly reduced manufacturing costs.

Ford, on the other hand, was able to get several fine versions of their OHC V8, one of which IS a DOHC, 4-valve design, into mass production and cost-competitive status. Different engineering teams, different management styles, different objectives. And most smaller-displacement engine-manufacturers have entirely embraced the OHC, multi-valve engine architecture and have figured out how to build them and control costs.

Pushrod or OHC, the main things that determine engine efficiency and power output (besides displacement, which is the big one) are combustion chamber design (responsible in part for breathing, but mainly for getting power OUT of the fuel that's consumed by turning as much fuel into energy as possible, for a given volume, by controlling the actual burning process), how well the engine 'pumps' or 'breathes' (which is simply how efficiently it takes air/ fuel in and pushes spent gasses out and includes all the variables of cam-timing, valve size and number, porting, intake and exhaust manifold design and the rest of the exhaust system), and how fast it can or needs to turn (RPMs) to do its job. It follows that a good-breathing, small displacement engine, like F1 uses, has to spin insanely fast to produce lots of horsepower, so they are all OHC designs.

Pushrod valve-trains are always heavier than OHC valve-trains, and weight of the valve-train is a limiting factor in how fast an engine can rev (a heavy part simply can't cycle as fast as a light part....think throwing a baseball as opposed to a bowling ball), but it is much LESS of a limiting factor now than it was in, say, the '60s, because of things like advances in metallurgy and lifter design. A fairly large displacement engine that breathes well and has good combustion properties just doesn't need to spin fast to make big power, so valve train weight becomes less of a factor in a street V8.

Engineering and accounting have to juggle a huge amount of data to come up with a viable production engine, and not every team gets the same results. GM in their LS series engines and Chrysler with their current Hemis, decided to go pushrod because the performance numbers were good enough to offset the increased costs and complexity of an OHC configuration like the Ford Modular V8. These are ALL EXCEEDINGLY GOOD engines, and I'm particularly impressed by what GM was able to do with a pushrod. Winning LeMans in class (several times), with a pushrod engine, is pretty damm cool.

The bottom line is, don't sneer at pushrod engines like the LS and the new Hemi. They've proven that they have what it takes, against many 'expert' opinions.

The LS pushrod GM engines, as shown in the top photo, are in all the C5 and C6 Corvette kits, and contemporary Camaros.

Edited December 17, 2012 by Ace-Garageguy

[jeffs396]

We don't need no stinkin' OHC American V8s when pushrod valve actuation will get you these numbers, with the potential for MUCH more:

http://www.venomgt.com/

[Greg Myers]

OHV's ? We don't need no stinking over head valves!

[MachinistMark]

Want to see what push rods are capable of? Take a look at mike Moran's 10 thousand rpm, 55 psi twin turbo , 4400 HP monster. Not bad for "obsolete"

[MachinistMark]

Top fuelers are in the 9-10k HP range. But that's on nitro. Moran's is a very conservative (his words) estimated 4400 on alcohol! Which is pretty insane.

[wisdonm]

How about answering Greg's question? Which kits include OHC engines?

[Ace-Garageguy]

How about answering Greg's question? Which kits include OHC engines?

Greg asked " where (what kits?) does one get these modern engines". I interpreted the operative word to be 'modern', not 'OHC', as in the sentence above, he refers to BOTH pushrod and OHCs in the phrase "they both make big power". The first photo he posted is a PUSHROD LS motor, and I referenced kits containing those, and you answered where the OHCs are located.

For the record, the LT-5 DOHC Chevy V8 is right where you said it is, in the ZR1 Corvettes and the Wagon Rod. The DOHC Ford is in some Mustang kits, and the SOHC is in other Ford, Mustang and Ford truck kits. MODERN PUSHROD engines, like the LS Chevy, are all over the place, any post '95 GM V8 powered whatever, probably. The modern pushrod Hemi is in recent V8 Mopars. Just a tiny bit of research as to what recent cars came with which engines will answer any and all availability questions, if cross-referenced against what recent cars are available as kits.

There's a DOHC GM 4.2 liter inline 6 that I don't brelieve is available at all, kitted.

Edited December 17, 2012 by Ace-Garageguy

[Greg Myers]

Actually it was intended as a multi part question with OHV vs OHC engines beining what got me thinking.Then realizing this is a model

car board,I thought I'd better work in the model part for those wanting to do their own "engine swaps".

[Ace-Garageguy]

Cool '29 truck, Greg. Isn't that the old old SOHC 427 Ford engine, which is 2-valve cammer heads and front drive on the ancient FE bottom end?

Edited December 17, 2012 by Ace-Garageguy

[Greg Myers]

Monogram Blue Beetle (or derivative) + Johan Maverick SOHC and PIPES

[58 Impala]

You know what they say about old school, if it ain't broke.....

[Ace-Garageguy]

OHC engines are kinda old school too, ya know? They've been around since before the 1920s. The history of the internal combustion engine is quite interesting. For instance, there were several DOHC heads available for the Model T. One Frontenac version is available in the AMT '27T touring car / XR6 double kit, the AMT Vintage Police Car kit ('27 T), and others.

[moparmagiclives]

It's not the way of actuation, its th fact that a valve has to be pushed open that is old hat. Where are the rotory valves at ????

[Joe Handley]

I can think of two major advantages of OHV engines vs OHC, DOHC engines in particular......

#1. Center of gravity, less valvetrain mass and is mostly lower in the block too which will help lower the engine's and vehicle's CG.

#2. Packaging, OHC and especially DOHC V engines are wider than OHV and especially Flathead motors. A good example would be Chrysler's 3.8l OHV Minivan motors, 3.5l SOHC "Prowler" motor, and 3.6l Pentastar motor that replaced both the 3.8l and 3.5l. The 3.8l doesn't seem much wider than a modern DOHC inline engine where the 3.5l is noticeably wider and the 3.6l looks huge, especially in the FWD vehicles.

[Craig Irwin]

1906 Peugeot, monoblock construction, twin overhead cams, four valves per cylinder, hemispherical combustion chambers, AND a desmodromic valve closing mechanism. Short of electronic engine managment whats new? And Chrysler had EFI in 1957, and GM had electronic ignation in 1964.

[Chuck Kourouklis]

Speaking as a guy who owns both, the DOHC is silky smooth and a winder, overjoyed to sing right into its rev limiter. The OHV is also a zinger by classic small block standards, but asthmatic and coarse next to the 32V - yet, also torquier from down low, and since it runs against higher gears, it actually has a prospect of high 20s mpg on the highway (actually hit 32 once under 60 mph drafting conditions). Don't think the cammer will ever get close, and that's the trade-off for squeezing 100 more hp out of 15% less displacement against a performance axle.

I'll repeat and maybe embellish some of what's been listed (and this is probably partial 'cause it's off the top of my head):

GM LS-series and derivatives:

Revell/Monogram 1997+ C5 Corvette

AMT 1997+ C5 Corvette

Revell/Monogram 1999 Silverado

Revell/Monogram Chevy SSR

Revell/Monogram 2005+ C6 Corvette (LS7 - Z06, LS9 supercharged - ZR-1)

Revell/Monogram 2010 Camaro

GM 5th-gen LT-series:

Revell/Monogram 2014 Corvette, available some time in 2017

GM/Lotus LT5:

Revell/Monogram 1989+ C4 Corvette ZR-1 (1/24)

AMT 1989+ C4 Corvette ZR-1

AMT Wagon Rod

Ford Modular and derivatives:

Revell/Monogram 1996 Mustang Cobra

AMT 1997 Mustang GT (SOHC)

AMT 1997 Mustang Cobra (DOHC)

AMT 1997 Ford F-150

Revell 1997 Ford F-150

Lindberg 1997 Ford F-150

AMT Phantom Vicky

Revell/Monogram 1999 Ford Lightning (just reissued, 5.4 DOHC supercharged)

Revell/Monogram 1999 Mustang Cobra (DOHC, just reissued)

Revell/Monogram 2005+, 2010 Mustang GT (3-valve)

Revell/Monogram 2007+, 2010 Shelby GT500 (5.4 DOHC supercharged - also available in Revell 1/12)

Coyote:

waiting and waiting

Chrysler late hemi:

Revell/Monogram 2009 Dodge Challenger

Testors/Lindberg 2006+ Charger (1/24)

Chrysler V10:

Revell 1992+ Dodge Viper and GTS (snap)

Revell Dodge Ram VTS (simplified glue)

AMT 1992+ Dodge Viper and GTS

Revell Dodge Sidewinder Concept (simplified?)

Revell 2003+ Dodge Viper and GTS

[Greg Myers]

http://www.coatesengine.com/csrv-system.html

[slantasaurus]

Speaking as a guy who owns both, the DOHC is silky smooth and a winder, overjoyed to sing right into its rev limiter. The OHV is also a zinger by classic small block standards, but asthmatic and coarse next to the 32V - yet, also torquier from down low, and since it runs against higher gears, it actually has a prospect of high 20s mpg on the highway (actually hit 32 once under 60 mph drafting conditions). Don't think the cammer will ever get close, and that's the trade-off for squeezing 100 more hp out of 15% less displacement against a performance axle.

I'll repeat and maybe embellish some of what's been listed (and this is probably partial 'cause it's off the top of my head):

GM LS-series and derivatives:

Revell/Monogram 1997+ C5 Corvette

AMT 1997+ C5 Corvette

Revell/Monogram 1999 Silverado

Revell/Monogram Chevy SSR

Revell/Monogram 2005+ C6 Corvette (LS7 - Z06, LS9 supercharged - ZR-1)

Revell/Monogram 2010 Camaro

GM 5th-gen LT-series:

Revell/Monogram 2014 Corvette, available some time in 2017

GM/Lotus LT5:

Revell/Monogram 1989+ C4 Corvette ZR-1 (1/24)

AMT 1989+ C4 Corvette ZR-1

AMT Wagon Rod

Ford Modular and derivatives:

Revell/Monogram 1996 Mustang Cobra

AMT 1997 Mustang GT (SOHC)

AMT 1997 Mustang Cobra (DOHC)

AMT 1997 Ford F-150

Revell 1997 Ford F-150

Lindberg 1997 Ford F-150

AMT Phantom Vicky

Revell/Monogram 1999 Ford Lightning (just reissued, 5.4 DOHC supercharged)

Revell/Monogram 1999 Mustang Cobra (DOHC, just reissued)

Revell/Monogram 2005+, 2010 Mustang GT (3-valve)

Revell/Monogram 2007+, 2010 Shelby GT500 (5.4 DOHC supercharged - also available in Revell 1/12)

Coyote:

waiting and waiting

Chrysler late hemi:

Revell/Monogram 2009 Dodge Challenger

Testors/Lindberg 2006+ Charger (1/24)

Chrysler V10:

Revell 1992+ Dodge Viper and GTS (snap)

Revell Dodge Ram VTS (simplified glue)

AMT 1992+ Dodge Viper and GTS

Revell Dodge Sidewinder Concept (simplified?)

Revell 2003+ Dodge Viper and GTS

For modern Chrysler Hemi's you left out Revell's 2006 Magnum SRT which has the 6.1 Hemi. There is also the AMT 2005 Chrysler 300C with the 5.7 but that engine is VERY poorly done with the exhaust manifolds attaching to the side of the engine block instead of the cylinder heads. Another source for LT Chevy engines would be the 2005(?) Cadilac Esclade from AMT, but I've heard that engine is also poorly done like the 300C's Hemi. I've never seen one in person so I can't say for sure.

Edited December 18, 2012 by slantasaurus

[moparmagiclives]

http://www.coatesengine.com/csrv-system.html

Now that's what I'm talking about !! Give me two for a cleavland, and enough room to stretch it's legs.

[Chuck Kourouklis]

For modern Chrysler Hemi's you left out Revell's 2006 Magnum SRT which has the 6.1 Hemi. There is also the AMT 2005 Chrysler 300C with the 5.7 but that engine is VERY poorly done with the exhaust manifolds attaching to the side of the engine block instead of the cylinder heads. Another source for LT Chevy engines would be the 2005(?) Cadilac Esclade from AMT, but I've heard that engine is also poorly done like the 300C's Hemi. I've never seen one in person so I can't say for sure.

Yup, I sure did! Although if we're talking presentable engines, only the Magnum really counts.

Escalade had a decent engine cover, but otherwise, it's as bad as you've heard.

[Chuck Most]

OHC is great, OHV is great, but this is all sillly when valve-in-block engines still have such a following even 50 years removed from the last domestic production units-

http://uncommonengineering.com/