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Discussion Starter #1
Hi all. I joined to ask for your insight. I'm new to setting up valve spring height on the small block stock heads. I'm working with a set of E7s. How do you address the difference in valve stem cap length between intake and exhaust valves? Stock installed height on intake is a strait forward 1.77". The exhaust, without the rotator and using a standard retainer is only about 1.68". If one were to order a set of springs and matching retainers, you would be faced with how to get the exhaust spring installed height to 1.77".

- Dan, aka Digger
 

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Comp and other sell offset valve keepers, + .050, -0.050. [email protected] can get you what you need, he's done a few I suspect. ;)
 

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you need to play with locks, retainers And shims to get the correct height.

you need .100 so a + lock and retainer.

gets expensive to play like this and the reason most order a kit from Alex’s parts which takes into considerion the valve tip length.
 

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I was told that once the engine has been run spring height will increase approximately .020" due to keepers being pulled tighter into the retainer. Well respected engine builder told me that, I've not personally verified it. I would imagine that the more spring pressure used would vary that, as well as retainer/keeper angle and material.

Jay
 

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Discussion Starter #5 (Edited)
Thanks for the lead. I looked at the Flowtech Induction website but am not optimistic Of forty "kits", the floor is 154# seated pressure and the sky's the limit on rates. FTI obviously caters to the high performance market. Sent RFI to them anyway but feel like I'm probably wasting their time.

I am working on a 1986 F-150 as a daily driver with a .470" lift cam and will use springs with a seated pressure ±100# with a 180# rate. Also, stock, stamped steel rockers. Plan B is to return the new Crane364211 cam and fall back to stock springs, intake valve retainers and exhaust rotators with a '94-'97 truck cam.

Edit: Crane part # is 364211
 

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I've ran a stock HO cam on explorer heads with 1.7 rockers using comp 942 springs. Its a single spring with a high enough pressure and doesn't require any machining of the heads.

 

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Discussion Starter #7
I have the springs I want to use. Erson 3300 . My machinist's proposal: cut the difference out of the exhaust spring seat or use -.050 keepers and call it close enough. Or -.050 keeper plus .030 intake shim and have them virtually equal but with slightly higher pressure.

Trying to keep the pressures as low as tolerable to promote longevity. Do this job once and not revisit it ever.
 

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Discussion Starter #8 (Edited)
FTI did respond almost immediately. I'm out of luck as they don't do low power setups. A+ for customer service though. Looking high and low for a stock dimension exhaust valve that features a .393" cap as opposed to the standard .481" cap. All aftermarket valves I have found have only the latter unless you go to a larger than stock valve head size.
 

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Discussion Starter #10 (Edited)
This seems like a lot of work when you can go to Alex's Parts and order a complete set to work with the OE valves for $125ish.

This sounds like it might be a flat tappet cam. Is that correct?

Crane 364211. It's a roller. Alternative is a F4TE roller cam. The spring kit you took the trouble to look up (thanks for that) does have the pressure and rate I was seeking. The fact that it comes with retainers that compensate for the cap length difference is promising. That it is listed for flat tappet leaves me with more questions.

I have e-mailed Alex's with my questions.

As mentioned, I'm new at this spring stuff. I believe I understand why rollers want more pressure and higher rate. So, my thinking is that I don't necessarily need the extreme open pressures when my build will rarely see over 3500 RPM. Stamped steel factory rockers will perform better/last longer at closer to stock rates. I'm trying to cram all the power as low as possible. With 3.53 gearing and a 4AOD I cruise well below 2000 RPM. No hard acceleration here either. I'm have even been considering using E6SE heads for basement power. Please don't comment on the E6s, I only bring this up to stress that I would be willing to give away a lot of high end HP for some gain below 2000.

Edit: Crane part # is 364211
 

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Discussion Starter #12
Crane 364211 specs
Intake Duration at 050 inch Lift:198
Exhaust Duration at 050 inch Lift:208
Duration at 050 inch Lift:198 int./208 exh.
Advertised Intake Duration:260
Advertised Exhaust Duration:270
Advertised Duration:260 int./270 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.445 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.470 in.
Valve Lift with Factory Rocker Arm Ratio:0.445 int./0.470 exh.
Lobe Separation (degrees):112
Computer-Controlled Compatible:Yes
 

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Discussion Starter #14
Crane 364211. It's a roller. Alternative is a F4TE roller cam. The spring kit you took the trouble to look up Here (thanks for that) does have the pressure and rate I was seeking. The fact that it comes with retainers that compensate for the cap length difference is promising. That it is listed for flat tappet leaves me with more questions.

I have e-mailed Alex's with my questions.

As mentioned, I'm new at this spring stuff. I believe I understand why rollers want more pressure and higher rate. So, my thinking is that I don't necessarily need the extreme open pressures when my build will rarely see over 3500 RPM. Stamped steel factory rockers will perform better/last longer at closer to stock rates. I'm trying to cram all the power as low as possible. With 3.53 gearing and a 4AOD I cruise well below 2000 RPM. No hard acceleration here either. I'm have even been considering using E6SE heads for basement power. Please don't comment on the E6s, I only bring this up to stress that I would be willing to give away a lot of high end HP for some gain below 2000.

Edit: Crane part # is 364211
Alex's has not responded to my email questions but digging deeper into their site I find what I believe is exactly what I need. These, or another suitable solution, these. Regardless of what I choose, Alex's appears to address what I am asking for here. Thanks @tjm73 for putting me with Alex's site.
 

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Discussion Starter #15
Alex's took my call today and were very helpful. Even though I already have springs and retainers, I'm leaning toward their spring and offset retainer kit. They also like the flat tappet spring kit being used with the mild performance cams. The Crane or the stock HO.
 
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