Cam Help

[fasterw18s]

Well, it appears my conversion to 18s will have to wait.

So, I'm rebuilding what I have and will need to change cams to be better on the spray.

Here is a quick rundown of the combo:
421 sbc
AFR 220s 2.08-1.6 303 @ 700 228 @ 700
1.6 Rockers
13 to 1
1100 Dom
2" Headers w/Mufflers 3 1/2"
TCI Group 6 Conv - 400Turbo
4.86 9" 31" tire
3200lbs w/Driver

I have a cam with a 110 LSA and 276 - 284 @ 050 dur I can use, but am not sure if this will be a wide enough lobe center to utilize the spray.

I'm looking at a 200 to 250 plate shot.

Thanx in advance for any help.

[Monty Mikho]

Hey Fast, I would go with a 114-115 LSA if you are planning on spraying 250 HP. 110 is not going to cut it with a 250 shot if you are looking to make some power on nitrous.

[fasterw18s]

I was thinking the same as well.

Here is my dilemma Monty, I need this to run DECENT off, but I'm looking for good #s on.

I know, I know, cake and all.....

With this in mind, would a 112 be a good compromise, or should I live with it and look for the big spray #s?

[Monty Mikho]

112 might work buy will not give you better overall ET numbers on. The convertor is going to be the tricky part to get the on and off number from. Personally I could care less what the car runs on motor. It's only a number that means nothing unless you are looking to run N/A classes. If that is the case I would look for 2 cams and 2 convertors to be as quick as possible on both..

[fasterw18s]

Well, I was going to run N/A, but not with these 23*heads.

But, I was going to do some bracket racing too, I know, YUKK!, but its what is available for now, and I didn't want to spray it when running that type of racing.

[Monty Mikho]

Doug, do you have a 9" rear in that thing? If so, maybe look into two different rear ratios. I was running a 5.13 for motor and 4.56 on nitrous for the 406 motor. I used a Coan 8" 5500 RPM convertor and only swapped the rear. On motor is went 9.82 and hose it went 9.11 (.026 x .026 pill with 6.5 PSI of fuel.. Pig fat) Car left nice on both nitrous and motor with the gear swap.. Otherwise it was slower on motor with the 4.56 in (10.25 ET)

[fasterw18s]

And stay with the 114-115 cam?

I was going thru the traps at about 71-7200 on motor before. But on the one run w/a 100 hit it was only like 200 rpm higher at 5 mph faster???

Is that normal?

I wanted a 5:13 to begin with, but was a little nervous if I did ever spray. But that sounds like a good idea.

[Monty Mikho]

I was using a 114* LSA cam on the 406 and seemed to run pretty decent on motor. Change of plugs and rear gear and it was good to go. :D

[fasterw18s]

Thanx Monty.

[Monty Mikho]

Go out, kick some @$$ and have fun doing it.. When ya gonna have the beast done?

[fasterw18s]

Well, of course, just as cash is needed, Karin's business slows down, and my stuff is doing well, but, it seems we never fire on all 8 at the same time.

Monty, any suggestions on a cam company?

I would imagine I will need a custom grind don't you think?

What I believe I want is a w/1.6 rockers 710 int 680 exh 114 of course w/276 & 284 @ .050 how does that look?

I figure if I buying, I might as well take full advantage of the heads. I have tons of clearance, and plenty of valve spring.

I was @ 688 668 106 268 264 before.

With a low comp motor, 13 to 1, it stands to reason that a wider lobe sep should be able to build more cyl pressure even off the spray, at least in my limited understanding of the combustion engine, so my N/A power seems it should be better than before with the cam I want.

Your thoughts?

[Chris Uratchko]

I wouldn't sweat 114 for N/A. Any high end N/A engine I build has no less than 112 LS, and sometimes as high as 116.

[Monty Mikho]

Doug, below is the cam I used for the 406. It was an off the shelf item from Comp Cams..


Journal size: 1.948
Serial Number: R 3620
Part Number: 19-000-9
Grind number: CS1047-344-5R114
Valve adjustment: Intake = .026" Exhaust=.028"
Gross valve lift: Intake = .727" Exhaust = .690"
Duration @ .020": Intake = 316* Exhaust = 344*
Valve timing @ .050": Intake open 28* BTDC Intake close 76* ABDC
Valve timing @ .050": Exhaust open 86* BBDC Exhaust close 38* ATDC

These specs are for cam installed at 114* intake centerline

Duration @ .050": Intake = 284* Exhaust = 304*
Lobe lift: Intake = .4850" Exhaust = .4600"
Lobe seperation: 114*


Chris, I didn't know they ran that much LSA in N/A motors... :shock:

[Monty Mikho]

BTW that was on a 1.55 rocker.. With a 2.100 intake and 1.625 exhaust..

[fasterw18s]

Chris Thanx!

So then my thinking isn't far off.

Wow Monty, that was a hell of a cam!!!! You wouldn't still have it around would you????HMM?

I only have 2.08 and 1.6 valves.

Well again, thanx for the help, and I am more convinced than ever my previous cam was holding my motor back!

Monty, I just today went and opened up a new income opportunity, refurbishing gym equipment for the 9, soon to be 10 World Gyms in Cloumbus. So it looks as tho I may have in the near future another business to pursue!

Maybe this time, I can hire 1 or 2 people to help out. :D

[Monty Mikho]

First off.. Congrats.. that sounds awesome. I seen your work in person and they picked the right man for the job. Besides where the hell they gonna find someone who can pick the workout equipment and weights up without a hi-lo unless they hire you? :-D

I donated that cam to a guy from GFZ who had his stuff stolen in IN a few years ago. I think his name was Tim and I really dont know what he ever did with everything..

[Chris Uratchko]

Chris, I didn't know they ran that much LSA in N/A motors... :shock:

It's rumor'd that some of the Pro Stock guys have run as much as 120 degrees of LS.

[fasterw18s]

Chris, Monty, am I confused, or will a wider LSA create more or less cylinder pressure?

And after answering that, why would a narrower angle be less friendly to nitrous or any power adder? Is there a point of diminishing returns?

Also, Chris, when applying the wider angle to a N/A motor, are you running very hi-comp?

[Jay Allen]

The idea to a camshaft is actually quite complex. I strictly look at the opening & closing events. This gives me an intake centerline (theoretical) and an exhaust centerline (theoretical). With the right centerlines the end result is *Lobe Serperation Angle*. If you go into a build-up with a particular LSA in mind you'll only be looking at 1/2 of the equation.

Here is a childish way of looking at.

If I say 2 + 2 you know the answer.

But if I say 4, how many different ways can you can get to 4? Infinate.

Chris is right. I know of a few teams that use 119 LSA regularly. I know of a very successful P/S racer who played with 123 LSA but did not have enough static compression to utilize it.

Good Luck!

[underdog]

Isn't it true that if you run that wide, you'll need a bushed block and a higher ratio on the rockers as well?

[Jay Allen]

Isn't it true that if you run that wide, you'll need a bushed block and a higher ratio on the rockers as well?
No you will not *need* those items. But.......

There are some .600" lobe lift stuff out there so high ratio rockers are not required, always. And what is a high ratio to one racer may be common place to another. I myself like the 1.7 to 1.9 stuff. It is fairly simple to bolt it on a cylinder head and the geometry isn't a nightmare. Now the 2.0 or 2.1 stuff is very nice & makes power (if the cam is right), but if you are not a well trained engine builder problems are ahead!

Bushing the block to me just makes common sense. Think about the machining of a block. We bore; align hone; deck; square deck; and sometimes use roller cam bearings. But how many people can honestly say that they paid attention to the lifter bores? There are some, but not too many.

How many guys will tell you that they built their engine *Too Good*?

I have a BBC customer who ran stud mount, yes stud mount rockers with .860" lift all of last year (1.8 ratio). The block was not bushed as well. It was a 478 deal that only saw 7200 RPM. 4.500 X 3.76 with Canfield BBC 310 heads on it. Visit my site and click on customers. He is the only truck in there! Trent would be more than glad to hear from you and answer any questions you may have!

Good Questions!

[k-star]

I am not trying to jack this thread but this kind of goes along with what is being discussed here.....

I was talking to my cam grinder about a cam for a 406 i was building. It's in a heavy car 3400 lbs, 4 speed and limited heads( 200 cc pro actions) It's going to be a basic N/A engine but there might be a plate put on it. I was talking to him about a good compromise cam... I was goin with a 110/112 C/L Then he told me something totally different then what i have been taught...

He said that on a small plate system 250 hp or less a cam with a 106 C/L would work better. His take was that the cylinder cooling of a 106 C/L would off set any benifits of the 112 C/L cam????? Any thought on this????

Keith

[underdog]

With that small a shot, I agree, anymore though, I think you'd be sending it out the exhaust, just my opinion of what I've seen using a 108

[Jay Allen]

I am not trying to jack this thread but this kind of goes along with what is being discussed here.....

I was talking to my cam grinder about a cam for a 406 i was building. It's in a heavy car 3400 lbs, 4 speed and limited heads( 200 cc pro actions) It's going to be a basic N/A engine but there might be a plate put on it. I was talking to him about a good compromise cam... I was goin with a 110/112 C/L Then he told me something totally different then what i have been taught...

He said that on a small plate system 250 hp or less a cam with a 106 C/L would work better. His take was that the cylinder cooling of a 106 C/L would off set any benifits of the 112 C/L cam????? Any thought on this????

Keith
Keith there is some truth to this. Heavy car, small shot, low stall speed, Hmm.......maybe. The cam at .050" would have to be very conservative and even more conservative at .200" for this to work. The number *Range* I'd say is 235* to 240* at .050 on the intake. The 106-108 LSA would be ok. Now to hang an intake centerline (I/C) on something w/o knowing what the lobe actually profiles at is like running through a house at night with the lights off! LOL

Like I said above, you get opening & closing events first, then see how much *LOBE AREA* is needed. You do this for intake as well as the exhaust. The PRODUCT of the two is LSA.

Thanks.

[k-star]

Keith there is some truth to this. Heavy car, small shot, low stall speed, Hmm.......maybe. The cam at .050" would have to be very conservative and even more conservative at .200" for this to work. The number *Range* I'd say is 235* to 240* at .050 on the intake. The 106-108 LSA would be ok. Now to hang an intake centerline (I/C) on something w/o knowing what the lobe actually profiles at is like running through a house at night with the lights off! LOL

Like I said above, you get opening & closing events first, then see how much *LOBE AREA* is needed. You do this for intake as well as the exhaust. The PRODUCT of the two is LSA.

Thanks.[/quote]

I can't run through the house at nigh with out the lights on because i keep stepping on rottweiler toys!!!!! OUCH

hey Jay would you want to talk to me about a hyd roller cam for a 427 sb..... Can i call you????

thanks keith

[Jay Allen]

hey Jay would you want to talk to me about a hyd roller cam for a 427 sb..... Can i call you????thanks keith
Absolutely.

1.734.730.2574. Evenings are best.

Check out the post I put on the thread "Chris I don't want to bust".

I made post on that thread about a 427 SBC I have been helping on.

[k-star]

Jay i just read that post... sounds close to what i have going on.... It's a 10.2:1, 427 sbc with 220 cc aluminum pro-action heads.

But here is the kicker. It's going to denmark... so i need the thing to be perfect in every respect. I am going to dyno it before it leaves to make sure it's right...

I'll call you on the old land line. It might not be untill after the july 4th wekend... I am going to cylinder head school for a few days and don't have much time untill then

thanks, Keith