HO's you gotta love them. Twenty five years ago when I was 16 I picked up my first HO motor and intended to drop it in my first car. In the end I still have my first car and left the numbers motor in. Good thing as my HO T/A now carries that motor while the numbers motor is slumbering its life away. Even as a dumb young kid I figured out that HO's are not just another round port motor but something truly special.
BJ: The M22 carries the same gear ratio's as the M21 and genarically us Pontiac PS guys tend to call them all M21's. Not sure why. Kind of like my cousin who is an original owner of a RA II convert Goat and he always called it a RA IV when I was a kid. Habbit I suppose. I have the stock M22 in my HO. It works great. We have a 3.73 gear and Scott was hitting consistent mid 1.90 sixty foot times this fall with it. That puts him in rare company as only about 20 of the 152 cars at the PS race got below 2.0 short times. He was one of only two non Corvette 4spd cars to do so. Bruno and his RA IV Goat was the other as I recall. I made one pass in the car all weekend and hit a 1.94 short time. The M22 with a 3.73 is an easy car to drive, well relatively easy as the one two shift sometimes can catch you out or point you East West on a North South track which is always less then fun.
Lloyd: You touch on a sticky spot at the PS races. If you cert your car they absolutely are a no no. If you are running at the head of the pack for your type of car and showed up with them we would likely ask you to change them for the following year. We know they have shown up and we have seen them. So far though those cars have not set the world on fire and they have been mostly left alone but a subject of on going conversation how to handle them. Some mid-year Corvette's have the same thing going on. The 1965 and older small blocks have 2.5" outlets for their manifolds and 1966 into the C3's have 2" out lets. Some later guys try sneaking on the older manifolds. Our testing of an L79 with all combo's kind of proved that they were not really an advantage at all or even somewhat. As a tech and racer I would prefer to not see them around for our venue. It makes it easy on us to not have to confront the situation if some one is really laying down the times. Our racing is for fun and not really about who brought the fastest car overall. There was a pecking order to these cars back in the day and it should still be there today. For us HO fans we just so happen to have a rare quantity in that our low compression motor will out run most high compression motors from the brand x guys. Sure is fun to beat a big rep high compression motor with a low compression motor that has a broom stick for a cam.
74 SD Formula: We have used several different cams. Wolverine and Melling have both been consistent performers for us. We had a short stint with Lunati cams that came up very poorly for us. We lost two AMC motors and a HO due to cam wipe out. We break all motors in on a stand carefully. No inner valve springs, Brad Penn break in oil or equiv., GM EOS (now discont.) or equiv. cam break in additive. When we are done we change the oil but stay with those items again even on the dyno. We want safety first at the expense of higher numbers. We have traded that combo out at the end of a dyno session once for Brad Penn racing synthetic oil. We got almost 6 hp as I recall. Anyhow the Lunati had great specs for a RA III/HO street motor. Being at the NHRA max lift rule of .424 on both sides but having a touch of extra .050 duration of 220/228. This cam is not legal in our racing but the numbers looked great for street motors. It did make good numbers on the dyno also. But in the end nothing really better then what we now have. I actually grind our own cams often now for Dan, Scott and I. But as myself and them are not really into cam sales we do not readily have them around or sell them. Usually if Dan is doing a motor or possibly Scott they give me a heads up and I have one made. I also help with a few motors a year for freinds beyond my own or brothers. As this is a hobby for me and I am already way to involved in my hobby I have kept them closely held so as to not let it consume me anymore then it has.
With that said when I am doing a non PS or part time racer we look at the engine program as a whole. I have changed center lines to match the project. This can also be done with Comp or Crane. They will sell you their 068 cam for example with your specified centerlines. I did that early on before creating our own cams. The Lunati experience tainted my trust in many companies and at that time we ran into several PS AMC projects and a Boss 302 project that no one made repo cams for. That got the ball going to replicate the originals by using NOS cams as our guide. This long winded dissortation I suppose is to say I might sell a cam here or there on a special basis or I would certianly help you find the correct center lines (lobe seperation) for your project and you could order a Comp or Crane that way. We have tested all manner of center lines and have a pretty solid idea what works best for each motor, compression ratio, trans type and rear gear. It does matter.
Bird 72: A properly set up 068 will give you 5200 rpm. We shift my HO at 5200 and it hangs in pretty tough until 5500. After that it signs off quickly.
Strictly speaking there is not much wiggle room on the cams in PS rules. Lobe seperations being altered is getting more and more attention now. Not good attention. I think that Dan and Bob are likely going to shut that down soon. But for all of you who likely will not or can not come and play with us it makes great sense. You have maxed out your stocker with out altering its nature. Except Lloyd who I know wants to come play with us as soon as possible. A general rule on most any 389/400/421/428/455 a 110 intake 114 exhaust and 112 lobe center line works well. The 350 HO's both '68 small valve and '69 big valve have their own set of rules. The 110/112 combo has great bottom response and will give several hunderd extra revs while not falling off as quickly after it peaks hp. It is a very tolerent setup for ping/gas issues also.
You guys sure have sucked a lot of info out of me!!!
Thanks, Mark
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