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removing valve springs

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Old Aug 23, 2009 | 08:23 AM
  #1  
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
removing valve springs

if the heads are still on the car, do you need a air compressor or would an air tank be sufficient to keep the valves closed to compress them. How much psi do you think it takes?
need to measure spring pocket for hopefully a spring that can take 0.495 on intake and 0.503 on exhaust on stock heads. dont want to have to machine so trying to find a spring that will take these lifts so i need the measurement to see what i have to work with.

Last edited by thirdgenlover; Aug 24, 2009 at 09:36 AM.
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Old Aug 23, 2009 | 09:22 AM
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From: Fairview Heights Illinois
Car: 1986 Irocz
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 3.25:1
Re: removing valve springs

Stock heads spring pockets for 083 castings =
083 head spring pocket outer diameter: 1.247"

Most stock 305 & 350 heads have identical dimensions.

Keep in mind that you can also increase clearance for more lift by using different retainers.
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Old Aug 23, 2009 | 09:34 AM
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
Re: removing valve springs

well the engine thats in it now isnt the engine it came with. the number on the head is 14102193. do you think i will have valve to piston issues running those lifts. it was recommended by comp cams and Greg seems to know what hes talking about, really knows his stuff. using stock ratio roller rockers too but their stock ratio for comp is 1.52

Last edited by thirdgenlover; Aug 23, 2009 at 09:40 AM.
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Old Aug 23, 2009 | 10:25 AM
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From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
Re: removing valve springs

Well since you've got those swirlport heads... I'd go find a set of decent performance heads and ahve those setup for the lift. No sense in bothering on those. You can find real TPI 350 heads (look for 083 castings) for $100 a pair easy.
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Old Aug 23, 2009 | 10:33 AM
  #5  
thirdgenlover's Avatar
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
Re: removing valve springs

no sense in messing with them? i cant see it being that much of a difference but heads are not in the budget. if i going to just be replacing with another stock style head ill just wait for actual performance heads when all the work of taking the heads off is worth it
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Old Aug 24, 2009 | 03:57 AM
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From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
Re: removing valve springs

The swirl port heads are pretty bad when it comes to actual flow.



See that giant swirl ramp blocking have your intake valve? Yeah... that thing is great for gas mileage and torque... but throwing a big cam at it will not make power like it would in even an 083 head. Those TPI heads are not bad at all. I personally think the TPI holds them back a lot more than the heads do.
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Old Aug 24, 2009 | 09:27 AM
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thirdgenlover's Avatar
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
Re: removing valve springs

so what does a tpi 083 casting head look like then. Like i said id probably do it but if i have to unbolt my headers (pain especially when some of the bolts fit tightly up against the runners themself) and then go find these heads and have to clean them up which is probably what ill have to do, it not worth the time and money to probably make another 20 hp or so.
plus the tq is a good aspect to still have


If someone had a set of 083 heads fully assembled, cleaned up, and ready to be bolted on, i would buy them right now if someone on this forum has some.

Last edited by thirdgenlover; Aug 24, 2009 at 09:36 AM.
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Old Aug 24, 2009 | 10:01 PM
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From: Fairview Heights Illinois
Car: 1986 Irocz
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 3.25:1
Re: removing valve springs

Originally Posted by thirdgenlover
well the engine thats in it now isnt the engine it came with. the number on the head is 14102193. do you think i will have valve to piston issues running those lifts. it was recommended by comp cams and Greg seems to know what hes talking about, really knows his stuff. using stock ratio roller rockers too but their stock ratio for comp is 1.52
None of the stock heads are going to be good for performance in stock condition without modifications, so I wouldn't worry too much about it.

You can't determine if there will be a piston-to-valve contact issue by just knowing the lift alone. The duration makes the biggest difference, and the best way is to mock the engine up with the cam installed and measure it by turning the engine a couple of times by hand.
Chances are you will have no problem with a streetable duration number.
If it's a stock engine then there should be lots of clearance for a good amount of valve-lift.
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Old Aug 24, 2009 | 10:09 PM
  #9  
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From: Indiana
Car: 87 trans am
Engine: 350 TPI bored .040 over
Transmission: modified 700r4
Axle/Gears: stock spline, 3.73 Eaton posi
Re: removing valve springs

so 305sbc, do you think that if going to use stock heads of course porting and valve train will have to be upgraded but with that cam do you think id be better off not to mess with the 083 heads that are modified and just get some aftermarket heads.
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Old Aug 25, 2009 | 01:47 PM
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From: Fairview Heights Illinois
Car: 1986 Irocz
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 3.25:1
Re: removing valve springs

Originally Posted by thirdgenlover
so 305sbc, do you think that if going to use stock heads of course porting and valve train will have to be upgraded but with that cam do you think id be better off not to mess with the 083 heads that are modified and just get some aftermarket heads.
That's confusing and I didn't say that. I meant that stock for stock, there is little to gain by swapping.

A set of ported & upgraded 083 heads would be a big performance improvement over a set of stock 193 heads.

I think there may be some pics of 083 heads on my photobucket.
www.photobucket.com/olympiadis3
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