Comp springs WTF????

[jpwalt1987]

If the springs were stable it is. Mine were very close but no problem.

I figure the 1203s ought to be plenty stable with the proper locators and what not. When you got the 200lbs on the seat what installed height did you end up at?

 

[bison]

I figure the 1203s ought to be plenty stable with the proper locators and what not. When you got the 200lbs on the seat what installed height did you end up at?

I can't remember exactly but it was about .060 from coil bind on the outer spring. I used machined locks from Tom. The large locks are a no go even with +.050. These shitty short stem valves limit spring availability. The r heads have the longer valves and it's much easier to get springs.

 

[jpwalt1987]

I can't remember exactly but it was about .060 from coil bind on the outer spring. I used machined locks from Tom. The large locks are a no go even with +.050. These shitty short stem valves limit spring availability. The r heads have the longer valves and it's much easier to get springs.

I'll give Tom a call tomorrow to see what he has to say and suggest. I also need to verify how much room I have for spring height. Thanks for the info Brian.

 

[jpwalt1987]

I can't remember exactly but it was about .060 from coil bind on the outer spring. I used machined locks from Tom. The large locks are a no go even with +.050. These shitty short stem valves limit spring availability. The r heads have the longer valves and it's much easier to get springs.

Tell me if I am thinking about this correctly......
The open height on the 1203s is 511@1.200.
If I have a lift of .545 that means I can shim it to a closed height at 1.745 right?? The spec for the closed height is 145@1.8. So the seat pressure ought to be a bit more at 1.745. Why do we need to have to use a keeper that increases the available space for the spring. Help me wrap my
Mind around this.

 

[bison]

Tell me if I am thinking about this correctly......
The open height on the 1203s is 511@1.200.
If I have a lift of .545 that means I can shim it to a closed height at 1.745 right?? The spec for the closed height is 145@1.8. So the seat pressure ought to be a bit more at 1.745. Why do we need to have to use a keeper that increases the available space for the spring. Help me wrap my
Mind around this.

You don't. I had about .050 more lift than you though.

 

[jpwalt1987]

Talked with Tom the owner of Champion Racing Heads today. Great guy and very helpful. The .0245 clearance around the seal to the ID of the spring is close but will be ok. Said he would run it on his own stuff. So a package of springs, retainers, locks, locators and shims is being put together based off of the measurements I gave him.

 

[BEATAV8]

Any news on yours Jeremy?

I installed the PAC1201's. No data yet but the car is assembled.

I went without any shims for now. A little concerned about getting much over 150lbs on the seat with my 853 lifters.

 

[jpwalt1987]

I just got the springs from PAC yesterday. I have to have the comp locators machined because the PAC locators will not work properly. I will end up with an installed height of 1.770 with no shims. Just the PAC retainer, 7*locks, and a .060 locator. Any tighter and I would have needed the + .050 locks. I had to cut the seals off very gently with a sharp chisel. They were on very good !!!! I am hoping to have it together tomorrow by 3.

 

[SloGN]

My current set up has 160 on the seat and 360 open. My cam is a dls grind 214/214 550 lift . I'm having a issue at 5700 were the engine just won't rev .

The spring are the dual ones that ta performance installed when I ordered the heads. I gave them the cam specs

 

[jpwalt1987]

My current set up has 160 on the seat and 360 open. My cam is a dls grind 214/214 550 lift . I'm having a issue at 5700 were the engine just won't rev .

The spring are the dual ones that ta performance installed when I ordered the heads. I gave them the cam specs

360 open ? That seems weak. What lift is the cam. I should be able to give an update on mine tomorrow. Locators are being machined right now.

 

[jpwalt1987]

Got my my springs changed out yesterday and today. What a freaking nightmare!!!! First off, I had to make a spring compressor out of an old rocker arm. Not bad to do. I had to cut the .530 viton seals off with a very sharp chisel being careful not to damage the guide. Took a lot of patience. Got everything measured out and had to add some shims on a couple of the exhaust seats. The locators from PAC would not work. The id for around the guide was too small and there would have been not enough thickness to locate the spring. I had the old locators machined down to .615 so they would clear the ID of the spring. All is good in that area. Installing the new viton seals was a chore on the passenger side next to the heater core. I had bought the proper install tool from comp but it was way to tall to fit. I Cut it in half and used a 3/8ths extension and swivel as an extension. That worked well. Make sure you remove the little springs from the seal. Otherwise they will be damaged. Checked the spring pressures before installing them. All were within 10-20 psi of each other throughout the range. I ended up with an installed height of 1.775-1.780. I have only started the car and let the springs heat cycle once.

I did pull a bone head move through the course of this job. I dropped a valve in the cylinder !!!!! I almost threw up!!! I managed to use a small magnet and a piece of welding wire bent In a cool shape to pull it back up into place. I had to pull the plenum to use the wire. Note to self...... Always make sure the piston is at the top!!!

 

[BEATAV8]

Encouraging early results! A Soft 22psi, 19deg adv, targeted 10.9 AFR. Straight E85. No knock retard and no knock counts. Didn't want to go too fast, so I only went through 2nd gear and a little bit of 3rd.

 

[BEATAV8]

Took her up a bit higher in the revs tonight. Still looking clean! Feeling like a pig in sh!t at this point. Thanks guys!

Will add some boost soon. Hope it will go to 27psi or so. Still on straight E85, no methanol right now.

 

[BEATAV8]

file attached

 

[jpwalt1987]

Took mine out today and caught with a Ferrari F-430 spyder!!!! Traffic was too heavy to get stupid but he saw what was up. Quick little first gear blast and about one second into second gear. Not really a race but got a thumbs up at the next light. Cool guy we all know in town. Anyway. Went outside of town and made a pull. First gear is spin city, so I ran it out in second gear. 6400rpm, 24psi boost, 19* timing, 10.7:1 AFR , alky on 8. ZERO KNOCK and the motor pulled all the way there. I shifted when the check engine light came on via the SD chip. I would say that the PAC 1203 springs did the trick. I am about to start hurting some feeling!!!!! Starting with that Ferrari!!!

 

[BEATAV8]

How much pressure did you end up with on the seat and over the nose?

 

[bison]

How much pressure did you end up with on the seat and over the nose?

Theoretically he should be over 470. With .580+ lift i was at about 510lbs. I dont know the exact number because the inner spring on mine was compressed more than the outer since it sits on top of the id locator for the outside spring.

 

[jpwalt1987]

The springs measured 150-160 @ 1.800 and 500-510@1.200. I put the stiffer springs on the intake valves. I had an installed height of 1.770-1.785 on the intake valves and 1.755-1.760 on the exhaust. I should have put a .015 shim on #6 intake valve. That would have brought it down from 1.785 to 1.770 which is what the majority of the intake valves are at.

Intake open height would be 1.225-1.240
Exhaust open height would be 1.243-1.248

I didn't have time to measure the spring pressure at the open height but i am sure it can be calculated from the measurements I gave.

I am going to reinstall my auto meter tach tomorrow so I can keep the rpms in check. Bison said I should not be over 6200 rpm.

First gear is absolutely useless. Even second gear at about 45mph it spins the MT DRs.

I had to have my comp locators machined to it the .530 guides and the id of the springs also.

 

[KL Mallender]

Is anyone else marking the date? The countdown has now been marked towards a repeat offender stating: WTF?
We will resume at a later date after the OP has a chance to survey the damages.

Kevin.

 

[jpwalt1987]

Is anyone else marking the date? The countdown has now been marked towards a repeat offender stating: WTF?
We will resume at a later date after the OP has a chance to survey the damages.

Kevin.

Yeah Kevin you got me. I didn't realize the title was a repeat of a similar thread I had started until it was already posted. Can't edit the title. I tried. My apologies for looking like a tool. ;-)
Do you have any input on the springs and valve train setup? How to calculate required spring pressure for a given rpm and valve weight?