13 replies to this topic

[Magoo]

Interesting article with fairly current info regarding 500 CID NHRA Pro Stock engines. One focus of the story is on cylinder block deck height. which largely boils down to a tradeoff between long connecting rod vs. short pushrod, with the short pushrod winning. 

 

 

 

http://www.enginelab...-power-numbers/

[Bob Riebe]

If I remember correctly, the DCRE was one of Oldsmobile's last ditch attempts at not leaving racing V8s to Chevy alone.

 

Thanks Mr.Magoo for that article, very interesting but in the past few months Hot Rod Magazine had an article that Pro-Stock needs to do something different as the class is shrinking badly.

One item was the cars looking nothing like what they are supposed to represent.

 

Why the have a 105 inch wheelbase to me makes no sense as the originals had a wheelbase inline with the Pony Cars of the day that made up most of the class.

Edited by Bob Riebe, 08 May 2015 - 18:54.

[desmo]

Good stuff, I hadn't looked at Pro Stock mills in a while.  In spite of the pushrod-2v architecture, a lot of the thinking has converged closer to F1 practice: look at the included valve angles and the piston geometry with minimal skirts confined to the thrust faces. Of course.  We haven't done the rod-ratio-L/D-whatever you want to call it thing here in some time. Nice to see dwell time brought into the conversation again.  I didn't know the blocks were done in England (Surrey, no doubt) for PS and NASCAR!

 

Mac, got any good photos of the ports in an x year old factory/big buck PS head?  If it's like F1, it's like 5 years or something before the collectors get their hands on real race iron and the curtain is drawn back a little.

[mariner]

great article, thanks a lot Magoo.

 

desmo is right , so many shades of F1 trends. The teams desire for pneumatic valve and FI is also interesting, not all hot rodders are neanderthal ( if any).

 

Given the smaller blocks today it would be interesting to see what sort of general race engine one of these could make. I guess endurance aside 1,200 bhp from around 650lb/300lkg engine weight would be realistic espeicailly on FI. The whole low block thing for less height and width would make one fit in a numbers of engine bays.

[Bob Riebe]

great article, thanks a lot Magoo.

 

desmo is right , so many shades of F1 trends. The teams desire for pneumatic valve and FI is also interesting, not all hot rodders are neanderthal ( if any).

 

Given the smaller blocks today it would be interesting to see what sort of general race engine one of these could make. I guess endurance aside 1,200 bhp from around 650lb/300lkg engine weight would be realistic espeicailly on FI. The whole low block thing for less height and width would make one fit in a numbers of engine bays.

It has nothing to do with neanderthal, if simply is they prefer simple over the more difficult.

 

It reminds me of when I was speaking with some gents in the pits at Road America back in the late seventies.

I got to speaking about chassis types with a driver and he said his boys pissed and moaned about how much harder it was to build a modified prod. car verses tube frame, that they should get rid of the prod. reqs.

 

Well this is the same thing, rather than hooking up a computer, it takes some real knowledge and involved work., PLUS they have to pay people with the knowledge of carbs.

 

If they had a choice they would do as the IHRA does and not restrict inches cubed,

The IHRA has the blocks with bore spacing off up to .5.30 which replaced the blocks with a mere 5.20 etc.

 

When you have restrictions you do what you have to do, when there are fewer restrictins, bigger can be better.

As NASCAR 358 inch cubed engines were up to 950 horse power, I am sure these could develop well over one thousand tractable horse power with ease.

 

Here is what happens without inch cubed limits.

 

http://www.sonnysrac...-engine-1350-hp

[Magoo]

If I remember correctly, the DCRE was one of Oldsmobile's last ditch attempts at not leaving racing V8s to Chevy alone.

 

Thanks Mr.Magoo for that article, very interesting but in the past few months Hot Rod Magazine had an article that Pro-Stock needs to do something different as the class is shrinking badly.

One item was the cars looking nothing like what they are supposed to represent.

 

Why the have a 105 inch wheelbase to me makes no sense as the originals had a wheelbase inline with the Pony Cars of the day that made up most of the class.

 

Yes, exactly:  the same trend that has damaged production racing series all over the world -- cars losing their production appearance and character, to the point where the audience no longer cares. There are no production passenger cars with 500 CID pushrod V8s, but somehow that's what Pro Stock ended up, and has stuck with them far too long. 

 

Another point where they jumped the shark was around 10 years ago when they allowed non-production bodies in an effort to equalize aero properties across the manufacturers. From there it didn't take long for the cars to morph into blobs. To me they look more like Pro Mods or Funny Cars than production racers.

 

Does this look like a Camaro to anybody? Who's going to care about this stuff? Who is going to pay $$$ to watch this? Here is one more reason the stands are empty. 

 

[Lee Nicolle]

Yes, exactly:  the same trend that has damaged production racing series all over the world -- cars losing their production appearance and character, to the point where the audience no longer cares. There are no production passenger cars with 500 CID pushrod V8s, but somehow that's what Pro Stock ended up, and has stuck with them far too long. 

 

Another point where they jumped the shark was around 10 years ago when they allowed non-production bodies in an effort to equalize aero properties across the manufacturers. From there it didn't take long for the cars to morph into blobs. To me they look more like Pro Mods or Funny Cars than production racers.

 

Does this look like a Camaro to anybody? Who's going to care about this stuff? Who is going to pay $$$ to watch this? Here is one more reason the stands are empty. 

 

Agreed. all so called 'stock' classes in all forms of motorsport have a total relevance issue when they look like that. 

IF they had a modified production engine, original style trans and body panels [fibreglass bonnets and scoops probably ok for drags] the public could then accept them. 

Nascar with characatures and things like V8 Camrys has no relevance and the same here in Oz with V8 Supercars.

[bigleagueslider]

Here in the US, there is better TV coverage of NHRA than there is of F1. I usually go to both of the NHRA events at Pomona and I have not noticed any drop in attendance. The reason guys run NHRA Pro Stock is because it does not cost massive amounts of money to be competitive, and they always get national TV exposure for their sponsors if they make it to rounds on Saturday and Sunday.

 

Regarding the use of pneumatic valve springs in Pro Stock engines, probably a good idea since the metal springs don't last long at the operating conditions.

[Canuck]

Is that an accurate portrayal of the hood scoop to roof line heights? That looks ridiculous. No wonder drivers can't see anything.

[Bob Riebe]

Here in the US, there is better TV coverage of NHRA than there is of F1. I usually go to both of the NHRA events at Pomona and I have not noticed any drop in attendance. The reason guys run NHRA Pro Stock is because it does not cost massive amounts of money to be competitive, and they always get national TV exposure for their sponsors if they make it to rounds on Saturday and Sunday.

tions.

Well that depends on how much massive is.

 

From here:

http://www.enginebui...ine-technology/

 

This level of performance and dedication doesn’t come cheap. In fact, you can “rent” one of these engines (and many teams do), for $50,000 per race or $1.2M per season. The way the rental program works is that you show up for a race and the engine builder delivers the engine to your pit. The engine builder handles all required maintenance at the racetrack (valve spring replacement, tuning, etc.). After the race, the engine builder picks up the engine and takes it back to his shop. While $1.2M may sound like an astronomical amount of money (the parts and labor cost to build one cost about $100,000), the technology required to field a competitive motor is priceless.

[bigleagueslider]

$50K per each of the 24 NHRA Pro Stock race events does not seem like a bad deal. Especially given the number of runs the car will make in practice, qualifying and final rounds. Then there is the added walue of having the engine supplier provide engineering assistance at the race. Consider what it would cost a team to operate their own engine shop and maintain their own supply of engines each year?

[Bob Riebe]

Good stuff, I hadn't looked at Pro Stock mills in a while.  In spite of the pushrod-2v architecture, a lot of the thinking has converged closer to F1 practice: look at the included valve angles and the piston geometry with minimal skirts confined to the thrust faces. Of course.  We haven't done the rod-ratio-L/D-whatever you want to call it thing here in some time. Nice to see dwell time brought into the conversation again.  I didn't know the blocks were done in England (Surrey, no doubt) for PS and NASCAR!

 

Mac, got any good photos of the ports in an x year old factory/big buck PS head?  If it's like F1, it's like 5 years or something before the collectors get their hands on real race iron and the curtain is drawn back a little.

I think you will find this interesting.

 

http://www.epi-eng.c...f_cup_to_f1.htm

 

 

This makes me wonder why Ford, who stuck with a live rear-axle on the Mustang for a long time, decided to go with the Mod. Motor.

It is a HUGE engine size wise but has to use forced induction to make HP equal to Chevy and Dodge's engines as Chevy and Dodge can simply add less expensive inches cubed for quick addition of torque and HP, whereas Ford spent a lot of money to simply get to 305 without going hugely under-square.

The multi-valves really only work best at high rpm and are more expensive to build and maintain.

 

I know the recent Engine Masters showed what Kaase could do with a Mod. motor but then he used his own special cylinder heads.

 

Next years Engine Masters competition with more categories, should be very interesting although this years, at least, showed the newest push-rod engines from Chevy and Dodge had an advantage over earlier one.

Although it makes me wonder, when the teams that run in the top three or four ran older engines, they were still winning usually.

Edited by Bob Riebe, 13 May 2015 - 19:57.

[mathewking21]

Yup.. Great article.

[Amaroo Park]

Excellent article thanks for the posting in.