Don Terrill’s Speed-Talk

I have gotten 447RWHP on a stock bolted crate with bolt-ons ( 384 RWHP on this engine as a baselline ), 468RWHP Fastrak, 489RWHP Ne-Smith, 497RWHP ASA, 550+RWHP RoadRace, & 597RWHP Outlaw 604. All of these engines were broken in on a DTS engine dyno with my break in oil and my lubes & filter afterward. On only a couple of these customer engines was I able to take the time to put them into my dyno car but I have probably done so with 30+ engines over a 10 year period.

I posted too long of a post on here to another 604 Crate HP question.

SJ Dave - never have sold a coated part for a crate engine other than my "ti-Cera-bide" header coating. My springs are stock GM springs that undergo my own 21 step treatment process. They have checked legal everywhere they have been torn down and have been on Championship winning ASA, NeSmith, Fastrak and UMP engines. Oh yea, reason I said ASA is because my springs outperform the conical GM's or Comps.

I had a non-disclose agreement with a major GM Supplier of parts that has been purchasing 40-50 sets of my springs per month for the last 3 years. That deal expired 2012 and I have posted on 4-m and a couple other places that I was working on controlled valve loft on the intake. All of the R&D was done in a Cup shop with laser inferometry to confirm results. You may have heard of Dyno cams, if you ran karts, and they built cams for lift rule Briggs engines that would result in 15-20% power increase, but you had to replace springs weekly or they would kill the valve seats. Karts really liked to have the lift improved but since the 604 cam has adequate lift, I have worked to get the duration curve on the intake better. Different headers, funky timing curve, and fuel curve lend to what I was trying to accomplish. You can identify it readily in many cars that have the boom-boom in the exhaust system when entering and exiting the corners.

This was actually perfected with my 350 2-BBL Nascar Carbs, later on the Winn-Dixie Whuppin stick in BGN, and then with a couple other folks still running the stuff. Now with the FI in CUP it will take some creativity to get it done but we got it done in the ASA FI engines for 3-4 years so adapting it to the new Penske/Illmor/MCLaren CPU should be pretty easy.

Thru a long process of elimination, I have found the right seat material to use in my "House" and re-man engines to allow running up to and past 7500rpms. Since I started out on these engines in 2000 it put me in a good position to get a head start on most folks.

Got probably 2500+ sets of the springs running all over the place and in 11 years of selling them. I like to re-treat them after 10-20 races as the procedure is much like the charging of a battery to try and control the resonant frequency of the material. I have not had a single failure, of spring, retainer and lock and they are 100% original GM Parts and legal on top of that.

BTW the new piston will not be legal by the rules as of now so why mess with them, If you win a big race you will get torn down all the way, why not be legal???

Part of the reason you hear a big difference in a good engine and an average one is when they are sealed up properly they pop like bacon sizzlin in a frying pan. Sealing the valve seat is critical on any engine so the seats have to be round, flat and perpendicular to the guide to even be in the ball-park. Ring seal is next on the list and I don't know of anybody around that does what I do to seal up a 604 crate.

i would really like to see one of your engines on somebody elses dyno ,,, thats all i'm gonna give credit to even get exciting about a post like that ,,, Fastrak checks fuel too ,,,

if your ring seal is so good ,, what cranking pressure are you seeing ?

As far as running on someone elses dyno, all of my engines run on other peoples dynos as I don't own an engine dyno ( although I am about 50% done on building my own ). I use Jeff Dorton, PRS - Penske Racing South, Tony Clements, Tony Corrente - RCR / Larry Wallace, Don Losito, Darrel Gabriel & Johnny Pruitt to name a few local guys. There are a ton of others that own Serdi machines that I have worked with. As far as chassis dyno's I have taken my carbs, engines and even complete cars to Willy's Carburetor shop to confirm my numbers for some of my customers up that way.

As far as confirming numbers to anybody, the only important folks in my equation are my customers; as long as they are happy, I have had customers win National Championships in ASA, NeSmith, Fastrak and UMP, they have been teched on a regular basis like weekly cause they win on a weekly basis and the bigger sanctioning bodies tech the top 3 pretty hard. As far as comparing numbers on dyno's the only numbers that count is the number you start with on a stock crate around 400 and what you end up with on that same dyno.

I only posted numbers on here because in the last 10 years I have not seen anybody post any numbers, much less 10 years worth of actual test data to confirm and support the results. Once you do complete all the work the final proof is in the pudding with customers winning with your products on the race tracks.

Only thing I like to get from customers is win pictures and I have about a 2 foot stack of them by my desk here dating back to our first pavement wins in 2001-2002.

I would welcome any other crate engine builder to post results no matter what they are, and discuss them intelligently rather than having to defend my numbers with folks that have never seen the inside of a crate engine.

Anybody out there with an intelligent question about the numbers? Why they are different and what all it took to get there???

I'll be putting up a post on here in the next week or so to describe some of my test procedures and methods, and how Chassis Dyno testing is way different from Engine Dyno testing ( other than the obvious ).

Got 27 carbs in in the last 2 week and I need to keep up my end of the bargain on FREE first pull evaluation on the chassis dyno. I'll be busy for 10-12 hours on Sunday at the shop. As many internet conspiracy theorists think I am able to derive some great knowledge from these carbs. Over 10 years of testing ( averaging 200+ carbs a year ) 64% of the carbs don't even test as good as a stock 650HP ( 10HP down ) out of the box that I use as my baseline test carb. 29% are + / - 5hp; 4% are +10hp better, 2.5% are more than 10HP better and .5% are +20-HP better. That means over a peroid of 10 years and 2986 carbs only 15 carbs were +20HP better than a stock Holley 650HP. Of that group a couple were house carbs tested when customers hand carried them in, and the remainder of the carbs came from PODUNK carb guys building them in their small time shops. And yes I group myself into the PODUNK group as I am just me and nobody else working in my shop, not too many folks know me except the folks that have found me by customer recommendation.

What does that tell you??? Either;
Holley makes a hell of a great Crate carburetor or most of the folks building them either don't know or don't care what they are doing building carbs for Crate engines. Every engine shop I dyno at has a stock 650HP to test on crate engines and they all do fine to warm up and baseline with that is until you bring out the "whupping stick".

You guys out there are the ones buying them why don't you tell me.


Mr. tshirt, what does Fastrak check for in their fuel test?
As far as cranking compression, I have seen over 200psi and as low as 100psi, and both engines were Fastrak sealed and running up front making 440-450hp on a DTS double 500HP brake and a DePak /Heenan/Froude 1000hp single brake. Those numbers are winning Fastrak races everywhere they run.

What does your 604 crate engine pump and how much power does it make?

Have you ever seen a set of $3500 Pavement headers run on a dirt engine and pick up 25RWHP? I have, wonder why that is ???

More importantly is how much intake vacuum do you create under load, what is the curve and where else can you measure it to determine ring and seat seal so you can start measuring dynamic leak down, and then using static leak down to help you tell when your engine needs help. Our ARCA lease engines were run on the chassis dyno before and after every race along with leak-downs and vacuum checks. Depending on the honing and engine style we would get 200laps / one race weekend out of Qualifier type engines +800hp, 500laps out of Intermediates 750HP, and 1000laps out of practice engines 700hp.

Just my opinion but, I think you are missing the boat and looking in the wrong place as static ring seal is a measurement device to find a problem and determine cylinder to cylinder problems. If you know what you are doing with hydraulic lifters you can make your cranking compression read what you want to. Go out and find some retired street stock engine builder and he might be able to help you out with that.

I post on these forums in the event that I might find someone interested in doing some different R&D with an engine program on somebody that might have a different thought process than me that will enable me to learn something.

raceman14: I'm curious about your new dyno. What are you doing for an absorber? Whose instrumentation and software are you going to use? How are you configuring the room?

I am not really familliar with carburetor tuning, but it really makes me want to know a little more about it, because I will be building a GTA stockcar, and if I run a Ford motor I guess it will be carbureted, unless a 5.0Coyote becomes an option.

how can you get 20 or 25hp from messing with the carb? is the air fuel ratio that far off when you have the right jets in a box stock 650HP?

Are the gains to be had from changing the fuel curve, or somehow increasing airflow?

raceman14: do you also build motors? have you worked on any SCCA GTA Late Models or old ASA cars? if so, is the 604 the way to go? how about a steel head late model with 650HP per SCCA rules? how much power for a 358 Ford roller cam .612 lift 1.6 rockers 46 lb crank 4.125 bore x 3.385 stroke 6.2 rods with the darts or Windsor SRs 2.02 1.60 no porting allowed and 650HP on a victor with a 7000rpm max? If you can make 550hp on the 604, this combo should be over 600 hp by 7000rpm, right?

I REALLY hope you guys aren't buying into the 550HP legal 604 crap!!! P.T. Barnum warned people 150 years ago.

Fastrak doesn't let you run anything except a regular collector ,, so a fancy set of headers they will call illegal ,,, read the rules

i'm sure all of your customers believe everything you say ,,, i know what i've seen on a dyno ,, a good one pulls about 430 hp ,, i watched that certain engine win a few races ,, in a great car with a talented driver ,, with legal headers

you say you can get this power ,, if they don't run your engines , they most likely feel they'll be at a disadvantage ,, so they fall for it and buy one ,, nuff said

i've been with a Fastrak inspector taking fuel samples ,,, he took them with him so i can't tell you for sure everything they check , alcohol content is one i watched him do ,,, if you think your the best cheater in crate racing go ahead ,, your why i tell everybody this crate stuff is a joke ,, if your line of crap makes you money , go ahead and keep telling it if you've found a pack dumbass's to believe it

if you think everybody else beside you test and run stock carburetors on 604's ,, your really off in wonderland now

I've NEVER seen or heard of one of our 604 crate carbs down on power or the same as a stock 80541 650HP carb. There is good power to be had, especially with oxygenated fuels or E-85 and a stock 650HP isn't going to be the way to go for either. Testing can be very subjective though.

i've saw a decent increase with a great set of stepped headers ,,, nothing else really makes a dramatic increase that i've ever saw ,, a little here and a little there with a carb ,, spacer ,, i'm working on a carb , haven't tested it on a dyno yet ,, it sounds excellent on an engine though ,, i did some stuff to his stealth carb , really brought it around ,, on the track ,, haven't put it on a dyno yet either

wether it's 430 horsepower or 625 horsepower, I don't care as long as whatever is being done is "legal" (passes tech) and shows repeatable gains in performance on the Dyno, it will win races and people will buy it.

that goesn't mean I agree with it, or that it is actually legal by the definition of the rules, just that you can get away with it and it wins races.

If the rules state "must use box stock Holley part #0-80541-1 with no modifications except for changing jets, then you can't legally buy a carburetor from some tuner for $1500-$2500 or even more, and run it in this class. it is not legal, you're just not getting caught.

There has to be an alternative to having a set of rules that allows a $25,000 604 crate motor to have a significant Hp advantage over one bought from gm and tuned with jet changes on a stock carburetor, the way the poor innocent rulemakers had originally intended, and the rules actually require.

I would like to work on some good methods for checking theese motors that will spot theese tricks with minimal if any teardown, and then on teardown have the tools to verify the illegal parts, no matter how good these guys are at cheating.

I don't care how good you are at getting away with it, there are people smart enough and passionate enough about promoting the sport and good fair competition, that they will find a way to police racing series that will remove some, but not all of this tom foolery to get back to the point where enough racers can afford to participate in a series of some form that gives them a chance at winning.

I've seen many rules come out over the years intended to reduce costs for the competitor, and probably half or more have resulted in increased cost to competitors, as the way to circumvent the rules to go fastest is far more expensive than the fastest parts available anywhere without restriction.

I think that the racers that want to change this need to get more involved in the rulemaking proccess and in the rule enforcement process, and get some good people put in charge of running the show.

It may end up being a series that is quite a bit slower or it might be faster, but if there is enough participation, and the cars look good, sound good, and out of a large field, anyone can win, the audience and the money will come.

I know that no matter how you make the rules, more money will still buy you a faster race car. I think there are ways to make enforcable rules that give the most competitors the best chance of competing on any given saturday night, or sunday afternoon, whatever. that's what most people in racing want, except for the drivers and owners/crews of the cheating/winning cars. And the money or prestige won has to come from everybody else in the sport to have anything to win. Everybody else being the fans, if any, the race workers, the majority of racers that wouldn't even want to win by cheating, even if they knew they wouldn,t get caught.

i have argued that taking vacume readings at 3 different RPM's , at different timing settings , to map out a chart for a stock ones vacume readings ,,, you would have a very hard time getting past that ,,, like 800 rpm and 10 degrees BTDC , 900 rpm at 5 degrees , 1000 rpm at 2 degrees ,,, something like that ,,,, any change to the cam , it would show up ,, and change to the CI would show a different reading ,

the ports don't line up well on a stock set of heads , and the valve job sux ,, thats 2 areas where you almost have to take it apart to check , but the easiest way to cheat is with the cam , and the vacume test would reveal any changes ,, ,, you would need a strobe tach ( portable tach ) so you wouldn't need the tach on the car ,, and a vacume gauge ,,, a vacume port on the spacer could be mandated for readings ,, you could catch them pretty easy ,,, some say headers will effect vacume ,,, it shouldn't have a drastic effect at idle RPM's I wouldn't think

vacuum sounds like a good way to test for a radical camshaft, and that's probably being used in some cases.

I was thinking more about the really hard to catch stuff. If the cam has more duration then yes vacuum would be lower and it would not pass a teardown most likely. I am not sure if they get out the dial indicaters and degree wheels, but I suggest something easier:

have a mandatory inspection hole over 4 or even all 16 that would allow mounting of an electronic depth guage(simple potentiometer) on top of the cover with a magnetic plunger on the end attatched to the top of the valve keeper. By simply hooking it up to an oscilloscope(digital or analog) you could crank the engine over and watch the scope. dual trace with RPM signal hooked up would help, but mainly you are looking for a different shape to the curve, and of course you are checking actual valve lift as well. The tricky cheater cams are the ones with stock duration and lift that have been ground to open and close the valve quicker, allowing more area under the curve. The scope pattern would show this, but a cam removal and some cam lobe templates would be needed to verify it in an actual disqualification.

And you could go all the way and write a computer program for a laptop with a scope hooked up to it to check the pattern agains a specified table and indicate pass or fail. this would allow non expert tech inspectors to do this.

autodoctor911 wrote:I was thinking more about the really hard to catch stuff. If the cam has more duration then yes vacuum would be lower and it would not pass a teardown most likely. I am not sure if they get out the dial indicaters and degree wheels, but I suggest something easier:

You're pissing into the wind.
Here's what many use to check the Crate cams now.
http://www.audietech.com/cam-pro-plus/techinspect.html
The quality of the stock 604 cams(Made in Mexico) is so bad, we can cheat even this system for a 15hp gain.

Crate engines have no place in Racing, and they've put a lot of good local engine builders out of business.
IF you want to run a less expensive class, go race bombers or any of the entry level classes.
The long term health of auto racing is tied to the health of the race engine builders, and the aftermarket parts suppliers. Crate engines are an attack on both of those groups.

My goal is to make sure the disparity in power is so great, that people will choose to race in non-crate engine classes, and that the cost to tech Crate engines will get so expensive, that track owners will do away with the crate engine classes.

Its already happening to an extent. Dropping the series to avoid the fees. Moving local racing into the forward direction is tough. Real tough. It has to become cheaper in order to have a real effect. The days of racing $200 jy engines are over. Even in bomber/4cyl fwd classes haven't taken off because of the overall expense of racing in general. $100 just to get to the track and back isn't going to work when you only make $2/300 a week. Budget classes are a thing of the past. Racing will be if we don't make it more affordable.

CamKing wrote:

autodoctor911 wrote:I was thinking more about the really hard to catch stuff. If the cam has more duration then yes vacuum would be lower and it would not pass a teardown most likely. I am not sure if they get out the dial indicaters and degree wheels, but I suggest something easier:

You're pissing into the wind.
Here's what many use to check the Crate cams now.
http://www.audietech.com/cam-pro-plus/techinspect.html
The quality of the stock 604 cams(Made in Mexico) is so bad, we can cheat even this system for a 15hp gain.

Crate engines have no place in Racing, and they've put a lot of good local engine builders out of business.
IF you want to run a less expensive class, go race bombers or any of the entry level classes.
The long term health of auto racing is tied to the health of the race engine builders, and the aftermarket parts suppliers. Crate engines are an attack on both of those groups.

My goal is to make sure the disparity in power is so great, that people will choose to race in non-crate engine classes, and that the cost to tech Crate engines will get so expensive, that track owners will do away with the crate engine classes.

Amen Cam King! Never a truer word spoken!
Crate's have not only cost us a lot of jobs and money it cost's the racer more also.
You need to have 1 legal engine and they usually have 2 cheater engines!
The Crate's are saving the racer's money!