HP,,, guess

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HP,,, guess

February 18, 2009, 07:43:21 AM

For x-mas my wife went in half on a set of new trick flow heads now in my possesion, any guesses on hp/ torque with stock cam and my other mods(in sig)

Also i am contemplating having a custom cam made, which will probably be the route i go, any guesses on hp/torque with custom and my other mods(in sig)

I am also going to get a better stahl for the aod, thinking the street B&M 2400-3200 lock up.But none of this will be happening till early-mid summer.

Thanks

HP,,, guess

Reply #1 – February 18, 2009, 08:03:59 AM

275-280.

HP,,, guess

Reply #2 – February 18, 2009, 08:51:50 AM

Around that.
No need for a cust cam and way over priced unless your racing,in my opinion.
Run a trickflow stage 1 with your 1.7s.
It's a nice all around cam and with the 1.7s and will give you lift of approx .530/.540.
I'm running that same combo but with a 70mm t-body 42's and a vortech,runs like a raped ape with a lopy idle.

HP,,, guess

Reply #3 – February 18, 2009, 09:34:33 AM

Imo custom cam is the only way to go, particularly for the street. I've had lots of OTS cams, it only took one custom to sell me on the benefits. In my experiece a custom cam will idle, have great vacuum, instant thottle throttle reponse, great power power band, rev with no valve float, good fuel economy, no issues w/P/V clearance. More expensive: yes. To me, worth every penny.

SBFTECH.com has a lot of great information which outlines the benefits of a stable valve train and a cam designed for your combination. If you have 10 or more posts there, you have access to the full site. It's worth the read (particularly the Myth & Rumors section).

HP,,, guess

Reply #4 – February 18, 2009, 09:41:48 AM

@dominator----just wonder if i would be able to run that much lift with my flat tops(no reliefs)
@vinnie----is that your guess with the stock cam or aftermarket?? I would be happy with 275,280 either way.

HP,,, guess

Reply #5 – February 18, 2009, 10:15:37 AM

My opinion was with the custom cam.It may be a little more...maybe.I've seen some guys get great power with a stock H.O cam.In the end it's up to you.I'm not telling you to go one way or another.My friend has a custom ground cam built for him using the specs of everything else that was given,and he was making about 5 more horses than the sport with an E303.

HP,,, guess

Reply #6 – February 18, 2009, 12:15:22 PM

I figured you had an HO longblock in your car,my bad.
No you can't run that much lift with SO pistons.
Around .500 is the max,ask vinnie.

HP,,, guess

Reply #7 – February 18, 2009, 11:26:57 PM

trick flow heads have different valve locations. They claim you can run almost any cam with flat tops. Ask tom.

HP,,, guess

Reply #8 – February 19, 2009, 12:49:11 AM

Yea but .530/.540 is quite a bit for flat tops.
Not sure about that one.

HP,,, guess

Reply #9 – February 19, 2009, 01:28:09 AM

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I figured you had an HO longblock in your car,my bad.
No you can't run that much lift with SO pistons.
Around .500 is the max,ask vinnie.

For the Umpteenth time Lift has almost NOTHING to do with piston to valve clearance!

PISTON TO VALVE CLEARANCE CHECK PROCEDURES:

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Piston to valve clearance is the relationship is just that, the distance from the valve to the piston during the most critical time in the engines cycle, that time is the "overlap". No other time during the engines cycle is the piston closer to the valve than in the overlap. Overlap occurs at the end of the exhaust stroke and the beginning of the intake stroke. This is the time when both the intake and the exhaust valves are open simultaneously.

A lot of people have used the max lift number when calculating piston to valve clearance and that is probably the single worst method. When the valve reaches it's maximum lift point the the piston is actually furthest away traveling down the cylinder bore drawing the intake charge in. The minimum clearances commonly used are .080 on the intake valve and .100 on the exhaust valve. For people using an aluminum rod it's a good idea to allow more clearance as the aluminum rods stretch when in operation.

To use the clay method take a 1/4th inch amount, cover the valve reliefs on your piston and rotate the engine one full cycle. Make sure it's 2 revolutions past top dead center. Take the head back off and peel the clay away. The best benefit of clay is that you can use an x-acto knife and cut it into sections and measure exactly where the thinnest area is, if there is any. Remember .080 and .100 minimum thickness.

The next method takes a little practice but is great if you dont want to take the heads off the car, although it will be necessary to replace the intake and exhaust valve springs on one of the cylinders. It's best to use a checking spring, but if you don't have a dedicated light weight spring, take a trip to your local hardware store. Remember the spring only has to have enough pressure to keep the valves fully closed and return an open valve back to it's closed postition.

Now you want to adjust the rockers to zero lash. What is important here is if you are using a hydraulic type cam, wether it be a hydraulic roller or flat tappet hydraulic cam. Do NOT preload the lifter. All you want to do is take all the movement out of the pushrod WITHOUT collapsing the plunger in the lifter. Make sure you do this adjustment when the lifter is on the base circle of the cam which is at top dead center on the compression stroke.

You will need feeler gauges set to 0.100 thousandth's. Start with your piston at top dead center and rotate one full revolution in normal operating rotation. The piston starts traveling back up the bore, the exhaust stroke starts to occur, and the exhaust valve will start opening. Watching the valve train you will notice the exhaust valve opening till it's fully open. As you are approaching top dead center you will notice the intake valve starting to open before the exhaust valve is fully closed. This is the area of overlap, usually about 10-15 degress before and after top dead center. Both the intake and exhaust valves are open and the piston is near the top. During this overlap point is when you want to measure the piston to valve clearance.

The piston is so close to to the top that you can push down on the nose of the rocker and actually feel the valve making contact with the piston. Now; with your feeler gauge set to 0.100, insert the feeler gauge between the valve stem tip and the rocker arm. If you can insert the gauge at 0.80 for the intake and 0.100 for the exhaust then you have enough piston to valve clearance.

It may take you some trial and error before you can identify the prescise overlap period at which you need to check the clearances, but this is a good way for someone that does not want to take off the heads.

I highly suggest you go through the steps above several times, it is VERY easy to miss the overlap, resulting in very unaccurate measurements. Work slow and this process can be accomplished by just about anyone.

Final note, if your measurements are say less than 0.10, for example there is .090 clearance on the intake you can retard the camshaft and play around with that but remember that will also affect performace charactersitics of the cam.

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Yea but .530/.540 is quite a bit for flat tops.

In 2 weeks, I'll be running .565".......

And with that picture, you have MY answer (guess the cat's out of the bag :hick: )

HP,,, guess

Reply #10 – February 19, 2009, 05:56:50 AM

Quote from: V8Demon;257633

For the Umpteenth time Lift has almost NOTHING to do with piston to valve clearance!

I knew that .....that was another reason i was planning on custom, tell them my set up, what i want out of the car and they deliver !!!!!!!!!!

HP,,, guess

Reply #11 – February 19, 2009, 10:20:23 AM

OH GOD v8 demon TAKE A FREAKIN CHILL PILL!!!!!!!!!!!
As he said we knew that but we don't need to go into literal time consuming about that right now.
He asked a simple question and the cam i suggested with those rockers will not work with his flat tops.
90% of people in here are not going to go through the calculations or sit and waste time with a degree wheel or clay.
Hell i won't and i'm a tech,went too school once don't want to do it again!!!
Read the post before you start freakin out.
Nobody needs it including me.

HP,,, guess

Reply #12 – February 19, 2009, 11:01:43 AM

The only way to truly know is to go through those measurements. I can surmise that since my post was longer than one sentence, you didn't read it. I DID read. You gave an erroneous answer.

Question:

Quote

I just wonder if i would be able to run that much lift with my flat tops(no reliefs)

Dominator's answer:

Quote

No you can't run that much lift with SO pistons.
Around .500 is the max,ask vinnie.

For a "tech" you do that on occasion. I'm sure you'll respond to this with something along the lines of how much power your car has. Just because you can follow an instruction sheet on how to mount a supercharger does not make you all knowing.

I've told you this before. THIS IS A TECHNICAL THREAD! IMHO it's better to be thorough. Perhaps by doing so someone will actually learn from it.

HP,,, guess

Reply #13 – February 19, 2009, 12:35:20 PM

Thanks for the info v8demon. That was the first time I've read how to check PTV clearance. And congrats on the custom cam.

HP,,, guess

Reply #14 – February 19, 2009, 02:04:27 PM

Let me add this, the bigger the lift will matter, because the exhaust valve will be out there longer to hit the piston.
I would be curios as to what valve Vinnie bent? There is a lot more to it than that. besides the floating without the right springs, with bigger cams.