Auto Racing: racing a 4-cylinder, fred puhn, flow bench


Question
QUESTION: i am racing a ford escort pony and want to know if i can do anything to quicken it up a bit. theres only a 1.9 liter engine and need to know what i can do to that little thing to make it keep up with the others

ANSWER: First you have to tell me what kind of racing you are doing. Circle track ?  Long or short? Road racing ? Or Drags?  Then you need to research the rules of your racing association, and let me know what they allow.  We'll go from there.  

Given the right circumstances we can get about 500 horsepower out of your 1.9 liter engine. One of the right circumstances is a LOT of money !

Let me know

Dan Liddy

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QUESTION: Circle track you really cant do to much to the car. its supose to be mostly stock...but believe me the amount of cheating people get away with is unbelievable the rep.for the 4-cylinders dosent really care...and its 1/4 mile clay track



ANSWER: OK  With a 1/4 mile track a lot of horsepower isn't going to help you much. but great handling will.  Get the book "How To Make Your Car Handle" by Fred Puhn, any book store can order it, and the larger ones usually have a copy on hand. It's about $16.00 and worth every penny.

What you can do to your motor that will help is to put the head on a flow bench and have the ports balanced. If porting isn't allowed, (probably not) have them do the bulk of their modifications at "finger depth"  that way, inspectors won't be able to see it easily. Also try to find valves that fit, but that have narrower stems, nobody will ever see it, and it will grab a bunch of flow for you. You might try the Harley shops or some of the forign manufacturers for valves,  Or get out your wallet and have Ferra make them for you. Keep in mind here that you don't need big ports, you need them to stay fairly narrow for added torque coming off. There's little sense spinning the guts out of it when the race is won on corner exits.  

Next time you freshen the motor, plan on micro polishing your crank so that your main bearing clearances are .0025" to .0030" and the closer together they are, the better. A good race shop can do this for you.  Rod clearances should be .0020" to .0025".  Piston to wall clearance is good at about .0040 but if you use new pistons, go to the loose side of whatever the manufacturer recommends. Needless to say, you should have the rods re-sized and the block align honed first. I am quite fond of Total Seal gapless rings, you'll have more legal compression than anybody out there.

Here's another trick. have the flywheel turned down on a lathe to lighten it.  You'll probably be able to remove several pounds of metal and that will do wonders for your acceleration. It's probably cast steel so you can turn all the extra weight you want, keeping the thickness to 5/16" or so around the outside.  Leave a little more under the clutch surface. The most imprtant weight is that which is around the outside circumference of the flywheel. You're trying to get rid of negative inertia. Let it get good and rusty before you re-install it so it looks like junkyard stuff.

That's about all I can think of at this time, but feel free to write for more info when you need it.

Best of Luck

Dan Liddy
Sarasota, Florida

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QUESTION: ic thanks a bunch...umm what about like the shocks and stuff like that? i know people cheat and weld up everything in the back end so the wheels are always straight...anything like that and also when im going around the track i get into 2nd gear and it seems to over rev...its a 5 speed...and when i shift into 3rd it has a big drop in power what should i do there?

Answer
OK,now you really need to get that book I mentioned. You may also be able to order it from Summit Racing  (www.summitracing.com) but before you start welding things solid, you should know more about what you're doing.

For instance, you may not want everything to be solid in the back, It could be that you could benefit from a little rear steer. Generally, welding a suspension solid is a bad deal.

As far as shocks go.  I'd suggest you get ahold of a Penske catalog and read up on the subject.  Keep in mind that a a set of real shocks for a real race car cost about $5000.00.  For short track use you might just try to get a set of high performance adjustables and set the rears for minimum rebound, and the fronts for minimum bump.

Do get that book and read through it, ther's a wealth of info in it, and I could spend pages giving you the wrong ifno.


Keep in touch

Dan Liddy