How do i check ptv without removing the heads?

 

I will place an order from Al at Manton tmr for 7.383 pushrods.

Thank you sooo much bud, im glad i finally can go forward.

 

You do it with a dial indicator and rotating the piston from 20 degrees before to 20 degrees after TDC of the exhaust stroke. You need a set of check springs though. It is rather time consuming, but if you have time while waiting for the pushrods it really should be done just in case.

 

Ok i will look for a how to tonight. Can i start re assembling the accesories/timing cover/ crank pulley befor receiving the pushrods?

 

Also, where could i order the check springs? Ill ask Manton if they have..

 

No, you will need to able to see the timing marks. Look for check springs at JEGS or somewhere. They are simply light springs that are easily compressed and replace the valve springs on one cylinder so you can compress them by hand. You may find something at a hardware store if you can get some dimensions from JEGS or somewhere.

In a nutshell, you set the crank about 20 degrees before the top of the stroke on the exhaust stroke so the exhaust valve is closing (so if you are still at the top of #6 firing stroke, then move the crankshaft 340 degrees and measure #6). Then use a dial indicator in line with the valve and depress the valve until it just contacts the piston. You do this for intake and exhaust. Write down the measurement and move the crankshaft 2 degrees so you are 18 before. Repeat the measurement. You do this in 2 degree increments until 20 degrees after the piston has reached the top. Since you don't have a degree wheel mounted to measure your angles you will have to use the teeth in the crank gear. Each tooth is 8 degrees (45 teeth) so you have have to take measurements each 4 degrees by putting a mark on the motor with a sharpie that lines up with your starting tooth (mark the starting tooth with a sharpie as well) and then move 1/2 way between, measure, then next tooth, measure, etc. so you are moving 4 degrees each time. You need to find the minimum clearance for each valve, i.e., the minimum distance it will move before hitting the piston. Not sure where the minimums will occur, depends on the cam overlap, LSA, etc. Since you will have marked the starting tooth you are using and where the minimum occurs. You may need to go back and do smaller measurements at the location of the minimum depending on the numbers you get.

Hope that makes sense.

 

This seems pretty complex...do you feel it is absolutley neccessary?

 

Just my input but the ms4 cam is designed to be a max effort cam in a "stock" motor meaning unmilled heads, stock size valves, stock head gaskets, stock pistons. Every motor will have some variances, some will have slightly more and some slightly less ptv clearance than others but numerous people have ran that cam with no issues just make sure to use good and the correct valve
springs because you don't want to run into any valve float issues

as far as the pushrods the 7.4 should work, that's the size most use when doing cam swaps and using stock rocker arms, now the thing to remember is most of your aftermarket cams are ground on a smaller base circle probably somewhere around .060 this would mean you would need roughly a .030 longer pushrod for the correct preload so basically a 7.425, using the 7.400 on a cam with a smaller base circle typically gives you the "sewing machine" sound people talk about after a cam swap

I would just run the pushrods you have now and since your not thrilled about the quality of them you can always swap them out later for a better brand and different size if needed, I'm sure you'll get the pushrod length tool figured out at some point you may just be overthinking it, your doing a lot of work at once but hopefully it will all come together, it's definitely going to be a completely different animal once you get it running!!!

 

Your call, many have run it without checking. I would personally check it on my car.

I would also upgrade the pushrods to a larger 11/32" OD that Manton makes as well.

Did some more reading this morning. Before ordering, did you by any chance measure the base circle? I am not familiar with the MS4, but it appears the intake and exhaust have two different base circles. You might want to discuss with TSP before calling Manton. You might want to check the dial indicator on the other valve on cylinder #6 too.

 

Al was saying 3/8ths last time i spoke to him

 

That would be great, not sure they fit in stock heads. I have done a lot of reading this morning, I see pushrod lengths all over the place. It might be best to use the dial indicator and check the preload on 6 both intake exhaust and then rotate the crank 350 and check #1. The numbers we came up with last night seem short in comparison to what others seem to find but the dial indicator doesn't lie. Since you already have the 7.400" pushrods it might be best to double check.

Note also that since you have stock 243 heads with the lightweight valves, the valve heights are different which will tend to shorten the pushrod over an LS1 head. A quick check will verify.

 

Do you have any advise once i bring it to the dyno shop? Like rpm limiter etc...?

I will be my first time ever getting a tune on any car..

 

All I can tell you is I worked with Tony Mamo when I did mine and he wanted me to set the limiter to 6,800 RPM. I didn't feel comfortable with that so set it to 6,600 RPM. You can probably get by with 6,800 but I would be concerned about rod bolt strength going any higher. Many guys simply slap in new rod bolts, but because of the way the rods are made they actually ovalize the bearing doing this.

 

What cam are you running? So all i need to do is request the rev limit and the tuner will set it into the tune/computer?

 

No! i did not measure the cam before putting it in...

I will check the other valve...but also, when i removed the dial indicator, and the plunger sprung out, it was still reading .0880.. Maybe i didnt depress the plunger enough when I did it yesterday...

 

Not sure I understand, was the dial indicator still reading that value once removed? Do you have a "hold" button on it (noticed its digital)? When you did this, you essentially set and measured the lifter preload directly.

Here is what I am seeing. Some guys with LS1's seem to run the 7.425" pushrods with the MS4. However, you have LS6 heads (correct me if I am wrong) that have a 0.024" longer valve than the LS1 heads. So, 0.024"/1.7 = 0.014" shorter pushrod or 7.410" (~0.014" shorter than 7.425") The one you measured is in the ballpark but I am concerned that if they run two different lobes on that cam you may have a different result on the other valve. Best to check it prior to ordering the pushrods.

Before I forget, one word of warning. When you start the motor the lifters will be very noisy because the measuring etc. has pushed some oil out of the lifters. They will need to pump back up so don't be surprised that the lifters are extremely noisy on first start. Just let it idle until they all pump up and are quiet.

 

Should.i squirt some oil on them befor adding the dropping in the pushrods? I also ordered the Redline assembly lube and comp brush.

I feel like putting in the pushrods the kit cam with and down the line if its too noisy to check with the IOEC method?

I really just wanna start the damn thing. Up here in Canada, summer is very short!

The guy at the dyno shop said I cant get a tune unless i have some sort of engin managment system... efilive? I really thought they would supply all that..

 

Put them in dry for measuring. Use the assembly lube with the final pushrod setup. Once you order the pushrods, unless you check PTV, you should be able to put the front on and radiator, ect.

However, you will need to rotate the motor for pushrod tightening (no spark plugs). I made a wrench to do that so I can rotate it with the motor together. Here is the wrench I made, just a simple cut off socket and a bar welded on. Others have simply ground flats onto a socket so you can use an open end wrench.

Also, someone posted that this works from Lowes if you have one around: Lowes Socket

 

A ratchet wont fit in there i guess?? Im sure i can make something work similar to what you have made

 

That socket from Lowes looks simple if you can find one locally. The issue is once the steering rack is back in place its a tight fit.

Also, don't use a longer bolt to re-install the harmonic damper (pulley), rent, buy or make a tool. Don't use the seal to align the timing cover, it will offset the seal and you may have leaks later.