stroked small blocks in the race cars?

[MAStuart]

Ed I understand what your saying. Brent is good at what he is doing. Like he said no one is twisting his arm. By his willingness to answer questions here makes me more willing to have him do some work for me. I am also sure he get work from others because of his willingness to talk about things.

As far as the books and thing you mention. We are way past that stuff. We have had a copy of Internal combustion Engine fundamentals for a long time. My son knows John. My son is doing a disertation for work on his PHD on full 3 dimensional multi physics computational fluid dynamics. The computer program took 55 hours to run 3 cycles or 6 rotations of a 3 cylinder engine. This is just the start of it.

One of my hobbies is scratch building multi cylinder engines. This includes making any patterns and castings plus any machine work involved. We have the equipment to do just about anything you could imagine to a small block ford. I think we could go as far as making a billet 289 block on our old machining center. We are not in the business of building engines for others. We have all the equipment for our hobbies. If someone asked for us to build one we would send him to Brent.

From my point of view the whole thread is bench racing. Also there are very few real secrets most have been around for years.

[1795]

Just read an informative article on camshaft design.

https://elgincams.com/wp-content/upl...Dema_Elgin.pdf

Have you guys heard of him previously?

Jim

[eschaider]

Originally Posted by 1795

Just read an informative article on camshaft design.

https://elgincams.com/wp-content/upl...Dema_Elgin.pdf

Have you guys heard of him previously?

Jim

Elgin goes back to the earliest days of hot ridding.

Ed

[blykins]

Originally Posted by eschaider

Elgin goes back to the earliest days of hot ridding.

Ed

Yep, and a lot has changed since then too, although the mathematics are still generally the same.

I like at the end how it talks about how "lofting the valve" is bad. If it weren't for lofting the valve, most NHRA stock eliminator guys wouldn't be competitive.

[1795]

There was a real nice discussion on his webpage elgincams.com in which he further discusses the nuances of cam design and use in an internal combustion engine, I was not able to copy the link. He compares valve overlap in race engines as opposed to street engines and how long duration of overlap may be fine in one and not the other. There is also an nice discussion about the effect of too much overlap on exhaust gases and how they may replace some of the fuel mixture and also have a detrimental effect on heat dissipation.

I was a little confused at first because there is Elgin Industries which Dema Elgin started and then sold to it's employees, which tends to make budget cams from what I have read. Then there is Elgin Cams, which is the new business that he started focusing more on custom and race cams from what I read.

Jim

[cycleguy55]

Originally Posted by 1795

There was a real nice discussion on his webpage elgincams.com in which he further discusses the nuances of cam design and use in an internal combustion engine, I was not able to copy the link. He compares valve overlap in race engines as opposed to street engines and how long duration of overlap may be fine in one and not the other. There is also an nice discussion about the effect of too much overlap on exhaust gases and how they may replace some of the fuel mixture and also have a detrimental effect on heat dissipation.

I was a little confused at first because there is Elgin Industries which Dema Elgin started and then sold to it's employees, which tends to make budget cams from what I have read. Then there is Elgin Cams, which is the new business that he started focusing more on custom and race cams from what I read.

Jim

This article? https://elgincams.com/camshafts/

[1795]

Brian,

That is it! Thanks. The guy does seem to know his stuff.

Jim

[Gaz64]

Originally Posted by cycleguy55

This article? https://elgincams.com/camshafts/

Yes, a nice article.

I don't see any mention of 17 arc versus 3 arc.

Gary

[1795]

Originally Posted by blykins

Yep, and a lot has changed since then too, although the mathematics are still generally the same.

I like at the end how it talks about how "lofting the valve" is bad. If it weren't for lofting the valve, most NHRA stock eliminator guys wouldn't be competitive.

Brent,

Do you think that he is referring to potential damage to the valve train via valve loft, or potential power loss? If his complaint is due to potential damage to the valve train, that does on the short term provide an increase in power, I can see why NHRA racers would go with that trade off. The engine is rebuilt more often and the damaged parts are then replaced, as opposed to a street performance car in which the person hopes to not have to build the engine.

Jim

[blykins]

Not sure on that one. It certainly makes more power when it's "engineered loft". On a stock eliminator, you're limited to factory valve lifts. Some of those back in the 60's were .450-.490". You can open the valve a lot further than that with some carefully designed parts, but when measured at inspection, it looks stock.

[blykins]

The thing about camshafts is that cam companies spit them out and most guys are happy with them because they have never tried anything else.

I've been testing and dyno'ing camshafts in Fords for quite a while, back-to-back, many times doing cam swaps the same day on the dyno.

Here's a couple of scenarios, tell me how much hp you think is different between the two camshafts, given that all other engine specs are exactly the same:

Scenario 1, 445 ci Ford FE:

Camshaft 1: 286/294, 231/239 @ .050", 114 LSA, 108 ICL, .630"

Camshaft 2: 286/290, 231/235 @ .050", 113 LSA, 108 ICL, .630"

(If you'll notice, the overlap is exactly the same on these two cams)

Scenario 2, 354 ci Ford Cleveland

Camshaft 1: 289/297, 259/267 @ .050", 108 LSA, 106 ICL, .700"/.660"

Camshaft 2: 287/315, 257/277 @ .050", 112 LSA, 108 ICL, .700"/.700"

(Overlap the same on these two cams as well)

[PDUB]

Originally Posted by blykins

Not sure on that one. It certainly makes more power when it's "engineered loft". On a stock eliminator, you're limited to factory valve lifts. Some of those back in the 60's were .450-.490". You can open the valve a lot further than that with some carefully designed parts, but when measured at inspection, it looks stock.

Very clever!