460 Ford Forum banner

Preventive Maintence for Racing Engines

42K views 50 replies 34 participants last post by  66prostreetFairlane 
#1 ·
Hey guys,

One of my pet peeves is for a racer to bring his cylinder heads in here that are all beat up and hurt,,,,,,,,because he was too lazy to perform preventive maintence.

Now then, broken valve springs are not that uncommon. It happens all the time. But when you break one, you should catch it, by that I mean you should realize that you have broken one. Own a valve spring tester and USE IT every weekend! The silliest excuse I have ever heard is that it is too much trouble to remove the stud girdle. Don't be so damn lazy! On C-460 heads you don't use a stud girdle because they are shaft mounted rockers. So to use your valve spring tester, all you have to do is remove the valve covers, but some guys act like even that is too much trouble.

I have seen heads come in here with two valve springs broken on the same head, and not only that, but they ran long enough to be broken in two different places, meaning both at the top and at the bottom. It gets worse! Futhermore they were run long enough to totally chew up the top edge of the spring seat cups and break off all that metal from around the perimeter! Where do you think it goes???

Another sign of going too long without a valve job is when you start sinking the edge of the titanium valves and the seat surface becomes cupped instead of flat. Once this starts happening the titanium valve starts wearing out quicker than a normal wear pace. The tool that you should be using is a feeler gauge. Constantly check your valve lash and when it starts closing up a bunch, that is a pretty good indicator that you are sinking the valve.

Steep seat angles such as 50, 52, and 55° are used by a lot of cylinder head gurus in order to increase the flow numbers at high lift and be able to win the bragging rights about how much their heads flow. However, they do NOT wear as long as a conventional 45° seat! If you are going to run steep seat angles, then have a full time crew chief and/or mechanic/engine builder that will tear the engine down very often. If you want to run a full season and make 300 passes a year, you better be running a 45° seat!

Spark plugs. They are the eyes that let you see straight into the heart of your engine!!! Learn how to read your spark plugs, they have a story to tell. In general, the better that you get you air/fuel atomized, or broken up into finer droplets and a more homogenous mixture in the chamber/cylinder, then the less jet you should have to run, and you should be able to pull timing out of it and make more power.

I can tell when a guy is running too much timing by the amount of detonation I see in the chamber. If the chamber has little pinholes that look like porosity holes, thats a sign of detonation. On the alum. heads with two valve seats, there are two areas where the alum. in the chamber comes to a point. When this point or tit of alum. starts to erode, that's a sign of detonation. (As a note of explaination, the current Roush heads have a one piece figure 8 seat. I'm sure that the other top NASCAR teams have one piece seats also).

Alcohol guys pay attention. After every race, R&R the spark plugs and spray light oil into the cylinders! Then reinstall a set of warm-up plugs. Gasoline guys don't have to do this after every race, but you should do it if the engine is not going to be run for 2/3 weeks or more. Likewise you should do it if you are close to the seaboard and have saltwater air or in high humidity situations. The bottom line is, you would be surprised at how bad and rusty the rings get. The second ring even more than the top ring. You can't have good ring seal, if the rings have to spend a 5 minute "warm-up" just scraping rust off of the cylinder walls.

One of the most important tools you can have in your toolbox is a leakdown tester. Use it! Use it while the engine is still warm. Record the data in a log book and continue to use it. If and when the recorded data ever starts changing, that will be a clue, that "Houston, we have a problem"! A leakdown tester also helps pinpoint the problem.
1. Air out the exhaust header indicates a warped or bent exhaust valve.
2. Air out the manifold/carb indicates a warped or bent intake valve.
3. Air through the radiator cap indicates a blown head gasket.
4. Air into the oil pan/crankcase indicates poor ring seal.

Oil filter cutter. Own one and use it whenever you change filters. Cut the old filter open and look at it. Run a magnet through it. Some particles may be magnetic and some may not, such as bronze or babbit. These engines will tell us something, we just have to learn how to read the tea leaves.

On the 850 Hp racing engines and higher, let's plan on replacing parts as often as needed. Develop a good preventive maintence program. You guys that were mechanics in the military know what I'm talking about. Check things often and replace them before they break. It's always more costly after they break. On the bigger Hp engines, valve springs and roller lifters are consumable replacement items, the same as spark plugs. Plan on replacing them at the end of each season, when you do that freshen-up over the winter.

I have leased engines in the past, and the tools that I furnish with a lease engine, if they don't already have them are;

1. Valve spring tester
2. "On engine" valve spring compressor
3. Leakdown tester
4. Feeler gauge/lash adjuster
5. oil filter cutter.

I feel that every serious racer should have at least these five tools with him at all times and he should use them often, in the name of preventive maintence.

Hope this helps,
 
See less See more
#2 ·
Charlie is right on the money. I loaned an engine to my younger brother for about two years of street strip duty. It was a good thing I could identify part of the end of a broken valve spring in the pan. Then I started looking up top and the easiest spring to see had a broken inner, number 1 cylinder front spring. The little brother didn't see it when he set the valves. I think that if I didn't go with the heavier of the spring option things could have been bad. The outer spring saved the day. The spring locator was even damaged. The engine got all new springs. I don't care if the springs are $500 and the lifers $400, now add in a damaged dry sump pump, the springs and lifters are getting really cheap now. Not to mention regrinding the cam and completely disassembling the engine to clean all the metal out of it. Oh I almost forgot the bent Ti valves that are so cheap to replace. :shock:

I do manage to put a few engines together each year and it really bugs me when they get destroyed for stupid reasons and or lazyness.

Good reading Charlie,

Kyle
 
#3 ·
Thanks for sharing those thoughts Charlie, I'm probably one of many guys on this site who have played with sub 600hp engines and will be stepping up to an 800hp engine in the near future. Looks like I'll need to order a couple tools and beef up the P.M. program.
 
#6 ·
c.evans said:
So to use your valve spring tester, all you have to do is remove the valve covers, but some guys act like even that is too much trouble.
These people should be bracket racing a small block. :wink:
 
#7 ·
I agree with Charlie in that EVERY engine has wear parts that are consumed as the engine is used. What happens sometimes is that you get someone who's used to an engine where even the valvesprings and rings last 100,000 miles. They don't know or understand that in their racing engine these parts are subjected to MUCH MORE stress and thus will wear out much more quickly, it's the cost of making more horsepower than a low stress stock or production engine and the higher the performance generally the higher the maintenance.

I have a tough time understanding a couple of the shops in the area that build engines for some river runner jet boats around here. They will build a big block and then put in a cam with .800 lift, a guy gets the engine is pleased with the power but doesn't understand why he can't keep it together for more than a few weeks at a time, duh... The valvetrain wears out that QUICKLY, this includes springs, guides, valve job lifters etc.

I would say that one of the real secrets is to figure out what the customer REALLY needs or should I say can afford to maintain as well as run and the build that. A bracket racer, circle track car boat or road car engine just has to make some sacrifices and compromises when it comes to power/longevity and figuring out the best compromise can be tough.. Glad we have guys like Charlie to illustrate these problems because they are something I deal with a lot in my work..
 
#8 ·
I always check my valve train every weekend I race, that might be a month but every time, it gets a going through. feeler gauge, bump the starter and a laminated card in my wallet does the trick. 20 minutes tops.

OIL it's changed every other outing whether it needs it or not. Filter is cut open... last year I used a system one so it is just inspected.

I also have a 1yr or 100 pass rule whichever comes first. Once a yr the bearings, rings, springs, lifters ( lifters rebuilt ) get changed for new stuff.

Aluminum rods too if I have them. I havent run any since I ran a 351C. but that was the policy then and it worked, I see no reason to change now. Unless the blower means shorter run-time.
 
#10 ·
Charlie's thread topic is an outstanding and comprehensive continuation to what I have mused regularly: that many a high-end race parts are gradually trickling into the hot rod market.

Well, quite a few hot rod artists seem to get "sticker shock" at the cost of these high-end parts and the cost of the engine builds. But the fact is that if you want the upper end quality componentry, you must pay the upper end price. (We've all heard the ol' saying, "you get what you pay for.") Too often, I see hot rod artists refuse to pay for what they really should utilize in their build and instead opt for the cheapo alternative in their very high performance engine...and then it bites them in the *** big time when that cheapo part fails...taking out much of the other componentry in the process of the destruction. And so now, the build has effectively cost the hot rod artist much, much more than if they had built the motor with the high-end quality parts in the first place.

Charlie's thread topic takes it from there. Once the motor is built, it ain't over yet. With high performance builds come high maintenance! And the preventive maintenance that Charlie suggests will ultimately cost the enthusiast LESS than that motor with the cheapo parts that grenaded and took the whole motor with it. Dave McLain's example of the marine builds that blow up due to lack of preventive maintenanace is a great example.

Paul

P.s: I wish to add one last piece of useful equipment to the preventive maintenance list: a mechanic's stethoscope. This is to be used more regulary than the equally important equipment that Charlie has already specified, since sometimes components may fail sooner than their typical/normally expected lifespan. A stethoscope can turn up a rod that is clunking before you can hear it with the naked ear, or a valve train problem that developed immediately after that last pass, etc.
 
G
#12 ·
I agree with Charlie 100%. I would even take it a little bit farther in saying along with engine maintenance to add the rest of the drive train,chassis, & suspension. A little time keeping things clean, taking a look at it, & putting a wrench on it can save you a lot of headaches, plus keep the shiny side off of the asphalt. The rest of a race car takes a beating too. Excellent post Charlie.. :D
 
#13 ·
I'm with Charlie on this one.

he know's how I stay with my program and took that into account when working my 598's new heads..haven't wounded a engine in 20 years of racing and pray to the big ford god (not charlie) it stays that way..Mr conservative ,thats me..Charlie is indeed a wise man,I am very appreciative he will share freely his knowledge..Thanks again Charlie..
 
#14 ·
Thanks for the info Charlie. As always, you keep us walkin the straight and narrow on these engines. I do have a question regarding a recommendation for a Valve spring pressure checker. There is one on ebay:

http://cgi.ebay.com/ebaymotors/ws/e...&item=280013755637&sspagename=ADME:L:RTQ:US:1

that I was considering to get that I can check the spring pressures while on the engine. Only problem is I cant figure out how I could measure pressure vs. lift with this device. What is your opinion of this type of valve spring pressure measure tool and if you dont like it, what would you recommend? You mentioned this list about a year ago and I bought the leak down tester right afterwards, now I need a valve spring pressure tester.

Again, thank you for always helping us novices out!
 
#15 ·
Broke 33,

The absolute best on engine valve spring tester is made by Lem's and my friend, Brad Buxton. It's used by all the top Pro Stock teams, but it's $600. You can view it at; www.buxtonengineering.com/vst_600.htm

The one in the e-bay auction is a hydraulic model also. It's made by Pro-Form and seems to be a copy of the Logan Smith Machine (LSM)hydraulic testers as sold by C.V. Products. These are much more economical in price and I'm sure they will do a good job for the purposes of a sportsman racer. I say go for it.

In regards to measuring pressure at various lift points, you don't. All you do is measure the spring pressure at the point the valve just comes off the seat. It takes a while to develop a "feel" for this, but with a little practice you will. Sorta' like a good mechanic, being able to tell with his hands, about how much torque he has put on a bolt when tightening it.

Hope this helps,
 
#17 ·
Thanks again for the info. Ill try this one to "cut my teeth on" and when I grow up to bigger projects, Ill grow the tool selection as well. I do have one more last question tho:

How do valve spring pressures typically change? Are they dramatic or gradual over time? Im guessing probably both depending on whether a spring has failed or just getting weak over time. So I guess the real question is when do you call a spring bad? Is it a certain percentage pressure drop from the manufacturers spec or is it a fixed pressure drop (maybe 20psi) when you replace them? For my particular application I m running a solid roller at .700 lift.

Thanks again for the info
'
 
#18 ·
Drop

The spring pressures generally drop gradually, like maybe 20 lbs over time. If you check one and it's off dramatically, say 40lbs or more, then look for a broken spring. I've found broken springs twice just using an on head spring pressure checker. Yes they do work and do it often, beats dropping a valve! If your springs are a little off on pressure, you can just shim them up, depending on your installed height. But then you'll have to buy yet another tool!
 
#19 ·
Great thread.

I personally love maintence, if I am shown what to do, I will do it everytime. I am a perfectionist/neat freak and I am very paranoid about my motors. I do agree and think people are lazy, it is fun to work on ****. The lazy dudes should have money to replace ****, or not have it at all.
 
#20 ·
dmontzsta said:
Great thread.

I personally love maintence, if I am shown what to do, I will do it everytime. I am a perfectionist/neat freak and I am very paranoid about my motors. I do agree and think people are lazy, it is fun to work on ****. The lazy dudes should have money to replace ****, or not have it at all.
I too, have worked on s**t.....it stinks. And when I'm done with my s**t, I don't replace it, I just throw it away. But on a more positive note........When everybody is out to get you, paranoia is just "good thinking". :D
 
#22 ·
Preventive Maintenace

I have put together a preventive maintenance chart that I use. It has both a check list of things to do prior to racing till 24 hours following race day. I also have a PM chart that gives me specific PM tasks and when they should be done i.e. weekly, monthly etc.

I find that both the check list and PM chart keep me honest and prevent me from forgetting what needs to be done.

Bill
 
#25 ·
dfree383 said:
Charlie,

Any recommended basic maintence charts / schedules avaliable? By HP Level or something? Might be a nice thing to have on the trailer wall.
I don't have any charts or forms, however I do like Bill's idea and maybe he can post something for us.

I do believe that close visual inspection is very important and these engines will tell us a story if they are "happy" or not. We have just got to learn how to read the signs. Everybody knows you can read spark plugs, but also you can read valve seats, and bearings. You can look for signs of unusual wear on valve stem tips, cam lobes, piston tops, pins, chambers and a dozen other places in the engine that are indicators in regards to what's going on.

Hope this helps,
 
#26 ·
Here's my Simple Race Checklist

I have this on Excel. If you guys want a copy email me at william.jackson@KLA-tencor.com and I'll send you an attachment.

24 Hrs Prior to Towing
Check tire pressure X
Fuel up vehicles X
Wash vehicles as needed X
Check and fill all fluids X
All certifications current X
Reservations made if needed X
Food and water purchased X

1 Hr. Prior to Towing
Visually Inspect tires X
Check fuel levels X
Race oil available X
Torque wrench available X
Road tools packed X
Oil pan packed X
Jack and jackstands available X
Rags available X
Water available X
Creeper available X
Tech manual packed X (this is a book of all the car's specs).
Check First aid kit available X
Road hazard flares packed X
Safety cones packed X
Road hazard triangles packed X
License and credit cards ready X
Tech manual loaded

Upon Offload at Track
Check tire pressure X
Check all fluids X
Check hose connections X
Fill fuel cell X
Re-torque wheel lugs X

Prior to Race
Check tire pressure X
Check oil level X
Check trans level X
Check and fill fuel cell X
Inspect parachute remove ribbon X
Turn on Master switch X

Following a Race
Record car temperatures X
Document stats and results X
Check under car for leaks X
Shut-off Master switch X
Install parachute flight ribbon X

Upon On-load to Trailer
Tie down car X
Check Master switch is off X
Check all lighting X

Following Race Day
Check car for fluid leaks X
Place car on jackstands X
Inspect under car X
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top