cutting down the valve guides- now springs are too big

[International47]

Hi as the title states, I cut the valve guide down for more seal to retainer clearance.
This is on a set is 193 heads.
Now I have a problem ( I guess i always did, I just didnt measure)

I used a Howards cams cutter ( Just like Comp Cams) to lowered the guides 5mms and the cutter narrows the diameter to .520" , flexible positive valve seals fit fine.
I left majority of the guide base intact.
Problem I found is both my Alex's .500 lift spring kit and the factory Ls beehive spring are too big for the bases.
Vortec bases measure out at .880 diameter, the TBI bases are .754
Vortec uses a single spring. Tbi uses the same spring, with an internal dampener.
I had thought I could use the vortec springs or the beehives.... because the TBI uses the same vortec spring.
Guess the factory cut the bases down for the inner spring.

I've looked at ID spring locators, but cannot find one that has the ID of .520 and an OD of .880
( I can finish cutting the valve guide all the way down to make the ID .520 instead of the .754)
but then the locator is also .60 thick, so it adds height back into the installed height.

My thought was that I could have a collar or sleeve made up. ID of .520 and OD of .880,
so it would be about .360 or 9mm thick.

But then I would not have to way to secure it to the head/ assembly--- maybe a tack weld.. if you can even mig weld cast to mild steel?

Anyone ran into a similer issue or can think of a possible solution?

possibilty something like this and drill out the center to fit?
Trick Flow® Valve Spring Cups TFS-31400433

 

[Hipster]

Pictures are worth a 1000 words. Trying to get my head wrapped around what your describing. On a single spring you only need to locate the outer diameter. There can be several tools involved. The beehive springs are larger than .880? If that's the case a seat cutter is needed. Got a link to the springs with more info? You don't want to unnecessarily keep shortening the guide with the dual purpose cutter.

 

[Erik the Awful]

I did zero cutting on my Vortec heads to put my beehives on and I run a .515" lift cam with no issues. My 193 heads did not have any "internal retainer".

You must be registered for see images attach

 

[International47]

Stock LS beehive spring and stock Vortec springs, and most drop in .500 lift vortec spring kits all have the same internal diameter of .880
The stock vortec guide base is .880, so yes they are a direct swap.
The TBI and Vortec seat pockets are the same diameter at 1.26.
TBI and Vortec have the same height from seat to guide tip.



the TBI uses the same stock vortec .880 spring....but it also has a inner spring (flat tappet cam vs roller cam)
I had assumed that TBI had the same guide base diameter... because they used the same spring.
I didn't account for or think that they made it slightly smaller to fit the inner spring.

All I did is cut the guide tip down for more retainer clearance and slightly smaller for a positive style valve seals. .520-.530 is a common size. The bases were not touched.

As described before, because the guide base's OD is smaller than the ID of the spring
( the stock vortec spring, the LS spring and Alex's .500 kit spring)
the spring will move around on the seat... which would lead to a broken spring.

Using a spring locator- used on lots of aftermarket aluminum heads-also called Spring cups on BBC's. Keeps the spring in a centered position.

my issue is that the ID of the locator or cup is not a common size.
(and I dont need/want the extra .60 in installed height)

So All I would really need is a sleeve or collar to fill up the space between the guide base and the spring ID.

The Pictures show the stock valve guide and the newly shortened valve guide tip.

 

[Hipster]

my issue is that the ID of the locator or cup is not a common size.
(and I dont need/want the extra .60 in installed height)

So All I would really need is a sleeve or collar to fill up the space between the guide base and the spring ID.

If the od of the spring pocket is larger than the 1.26 replacement springs it would have been too large for the stock 1.26 springs. I'm still not really undertanding because with a single spring all you need to worry about is locating the od. If the od of the spring pocket is too large or too small then an .060 deep seat cut at the diameter of the spring cup is the best way to approach it. Tbi heads aren't really worth the effort as they are out of breath and fall on their face @ 4.5k rpm. I thought springs cups could be had in .030 thickness but might be mistaken. Not advisable to tack hardened steel cup to cast. There's also +/- .050 retainers out there, but idk if can be had for beehives.

 

[tayto]

what cam are you going to run?

 

[International47]

If the od of the spring pocket is larger than the 1.26 replacement springs it would have been too large for the stock 1.26 springs. I'm still not really undertanding because with a single spring all you need to worry about is locating the od. If the od of the spring pocket is too large or too small then an .060 deep seat cut at the diameter of the spring cup is the best way to approach it. Tbi heads aren't really worth the effort as they are out of breath and fall on their face @ 4.5k rpm. I thought springs cups could be had in .030 thickness but might be mistaken. Not advisable to tack hardened steel cup to cast. There's also +/- .050 retainers out there, but idk if can be had for beehives.

Thank you for responding and attempting to give some ideas

the issue has nothing to do with the spring pocket.
the spring pocket on TBI, Vortec and LS are all 1.26-1.27.
Vortec and Ls aren't really pockets- more of a flat machined pad,
same goes for the all the intakes on a TBI,
only the Exhaust onthe TBI was machined lower .125"- to allow the use of a valve rotator.
All 3 also have the same OD of the spring 1.250-1.265.
All 3 springs also have the same ID at .880.

The issue is the guide, specifically the guides OD in relation to the Spring ID.
Vortec and LS are .852-.880, to hold said spring into place without moving.
TBI- even though it uses the same spring as the vortec- and same size as the LS- has a smaller diameter guide base.
therefore it will not hold the spring in place and allow the spring to move around- leading to a broken spring.

TBI guide diameter measure out at .754" so it is .126" too small to hold/center the spring.

.754 is an odd ball size as its smaller than gen1 heads (.785).
So lots of the spring locators and cups that are avalible, are not exactly usable without attempting to drill the centers larger to fit over the odd ball guides....or machine the guide all the way down to the seat to use the more common size .520-.530 locator.

yes +/- keepers will move the retainers, but I think +30 is max for the self aligning rockers.

Yes stock TBI heads are not the greatest for higher lifts or high rpm, but for a normally driven street vehicle, they make lots of torque and work great, with a little porting... ok maybe more than a little, they perform as good if not better than a vortec below .400 lift/ 4k rpm.

Vortecs do add a bit more complexity and cost to the swap- new intake, tbi adapter, moving fuel lines, coolent bypass, egr issues or very pricey tuning to eliminate egr, searching hard to find a set not cracked.

Springs/retainers, valve seals (2 valves) gaskets, and my time grinding a crap load of metal away. Is only about $400.
Finding vortecs, cleaning them up, springs, intake, adaptor, tuning is an easy 1k cost.

Thank you very much for the response, and attempting to understand my question/problem.

I guess I was looking for someone who has put newer aftermarket springs on a TBI.
Not just thrown on a set "Z28" springs, which are all over the map for sizes and spring rates.

But maybe that's where I need to be,
anyone put a .500 lift "Z28" spring on a TBI?
(90-100lbs seat, 280-300 open)

Thanks again.

 

[International47]

what cam are you going to run?

I havent decided yet, I have 2 sitting here,

Melling 1336 ( 1995 LT1 copy), and a summit 1102.
both top out at 460ish lift.

I have a running 1995 tbi in the truck right now- non roller flat tappet
And on a stand- needs aligned honing- is a 1993 355-roller motor.

Leaning towards the flat tappet just cause the motor is already running.

 

[International47]

So I have bought the spring cups and summits spring kit to match the cam- ment for older Gen1 heads.
.490 lift summit springs with the inner damper measure a inside diameter .774", the TBI spring base is .761"
Its a much better fit but the springs are still a bit loose.

The TBI's set up seem" loose" when compared to vortec and Ls springs, on the vortec heads, the springs fit snug onto the base and dont wiggle.
Vortec bases .870" vortec spring is.864, LS .854.

Is the .013" larger spring going to be a problem- spring walking around on the seat?

The idea I had was to find someone to machine out the centers of the cups to fit over the tbi guide base.
then the springs are held into place on the outer diameter of the spring, instead of the OEM inner diameter design.

Any thoughts? Or see a problem with using the summit springs?