I need help with cam recomendation.

Engine is a 383 cui, SLP headers, canfield 195cc heads, accel superram, TH700 and 3:27 rear ens. Stall speed is 2400 rpm and comp will be 9,0-10,4
Currently I'm running TPIS ZZ9 212/224 ,484/,520 113 camshaft but my engine broke I have to tear it down so why not change cam?

The car is a daily driven/ weekend racer and will not se 6000 rpm very often!

I've search alot but most of the cam seems to be to fit LT1 engines with short runner intakes.

Have been thinking of LPE219 219/219 ,525/,525 112 this combo has been proven many times (without a blower....) then LPE has a blower cam LPE220 215/220 ,530/,560 (1.6) 112

What do you think? any suggestions?

 

Does it have a supercharger?

 

In general, long runner intakes (TPI, Superram, LS1) prefer single pattern cams. Conversely, short runner intakes (LT1, Victor Jr.) prefer dual pattern cams.

There are two reasons for this. The first is that the long runner intake causes the ram-tuning effect. That is, that the momentum of the air in the runner continues to fill the cylinder during the compression stroke. So, you have to close the intake valve later to get the benefit of this. The second reason is that the longer runner will restrict air flow at high rpm. The longer intake duration will give the engine more power at high rpm to compensate.

Of course, this assumes that the heads flow reasonably well on the exhaust side. If the exhaust port is poor, more exhaust duration will be needed to compensate. For instance, Vortec heads flow very well on the intake and marginally well on the exhaust, so they run better with dual pattern cams.

I didn't see a supercharger listed in your spec's, so I'm assuming you're naturally aspirated.

What is your compression ratio? Is it 9.0 or 10.4 / 1? It makes pretty big difference for a cam recommendation.

If I were you, I'd use a Comp Extreme cam because it has the quickest ramp rates of the commercially available hydraulic roller cams. The up side is that they will allways make more power and torque than other cams. The down side is that you have to have a stout valvetrain to handle the quick ramps. You need to run 130 - 140 lb of seat spring pressure or the cam will not perform properly.

Finally, the numbers: A good cam choice would probably be Comp Extreme lobes 3314 intake and exhaust on 106 and 114 centerlines, respectively. This would make it a:

276/276 adv.
224/224 at .050
.536"/.536" lift with 1.6 rockers
110 LSA, 4 deg adv.

Or, if you're willing to spend some time fiddling with valve springs, you can upgrade to 3192 lobes, which would net the same timing spec's, but increase lift to .605".

If you want to try something a little unconventional, you can use an aggressive lobe on the intake like the 3314 or 3192, and go with a softer ramp and less lift on the exhaust. This works well with long-tube headers and a good exhaust system (<3 psi backpressure). Most Pro-Stock engines use this method. The restricted exhaust through the middle of the exhaust stroke helps pull a vacuum during overlap and scavenge in intake air. Also, the slower opening of the exhaust valve doesn't send as strong of a shock wave down the header tube to disturb the gas dynamics and reflect back to the port. If you really wanted ever last bit out of your new cam, I'd use a 3192 intake lobe on a 104 centerline and a 3109 lobe on a 112 centerline on the exhaust. This would give you:

276/276 adv.
224/220 at .050
.605"/.544" lift with 1.6 rockers
108 LSA, 4 deg adv.

Again, all this could change depending on your compression ratio.

Mike

 

ooopppss.. FORGOT 9 psi PROCHARGER............

The comp is/was 10:4. But something is "bad" in the engine, If I have to replace the pistons I will lower the comp to about 9,3 or something........Will tear it down soon.........

I know the LPE 219 makes good power with the SR, but will it with a blower?

 

Oh D@MN! All that and it's supercharged. . .

Anyway, I wouldn't use that 219/219 cam with a supercharger. You need dual pattern. To complement the super-ram's mid-range power, I'd use a 3190 lobe on the intake with a 110 centerline and a 3192 on the exhaust with a 118 centerline. This makes it a:

266/276 adv
214/224 at .050
.565"/.567" lift with a split set of 1.6/1.5 rockers.
114 LSA, 4 deg adv.

If you don't want/can't afford to use 1.5 exhaust rockers, you can substitute a 3119 lobe in for the exhaust, which is 280 advertised, 224 at .050, with .560" lift (1.6 rockers).

Again, you'll need to verify/set-up your springs for around 135# seat pressure.

Mike

 

I forgot to mention that Rich Krause made 600 rwhp with that 214/224 cam with a Vortech S-trim on a 383 LT1.

Mike

 

I have 1.5 rocker so I'll probably be keeping them, dont have the $$ to buy new ones I think this rebuild is going to cost some $$ anyway........

Is this a custom made cam? CC online catalog isnt workin.....
I would really lika a of the shelf cam so I can get it quickly...........

Thanks for the HELP!

/N.

 

1.5's would give you .530" on the intake, .567" on the exhaust.

Maybe later, when you save up $120, you can get a half-set of 1.6's.

The 214/224 Extreme cam is a custom grind. They don't make any good LT1 blower Extreme cams "off-the-shelf". If you insist on something "off-the-shelf", you'll be compromising the combination.

But. . .

http://www.speeddemonmotorsports.com...engineLT1.html

has them. CC-3190-8-3192-8-R14+4 is their part number.

Mike

 

The 3190/3192 on a 114lsa is a great street blower cam, like Mike said. Since using it I have recommended it to perhaps 10-12 people and all have been satisfied.

Rich Krause

 

Last question?

Will it fit my long runner intake? (superram) I wont pull over 5600 rpm.....

/N.

 

The rpm range of that cam won't be dramatically different from your existing cam.

 

THX!

I've learned alot from this post and the other "cam" post in the past......

If you have the time please explane how "the correct" camshaft can reduce pre-detonation. How and why?

/N.

 

A cam with a later intake closing point (further away from BDC) will lower the dynamic compression and the tendency towards detonation. Since the valve closes later, the induction charge is compressed less. This has a very similar effect to lowering the static CR, though there are differences between the two approaches.

Rich Krause

 

Ok..

My current cam has (-)6.2 deg overlap is this much?

and the intake valve closure is 32,8 deg is this much?

just trying to figure out my current setup. I have had some trouble with KR and this maybe could have something to do with it............

 

If you post all of the valve events, the cam card specs, and your engine specs (bore, stroke, rod length, cc size, piston dish/dome, etc.) it would help in answering your question.

Rich Krause