Summit has them listed with steel or Ti retainers.

Info I found from "way back" says there are four different spring & retainer combinations, so the purchaser needs to determine which spring option fits their application:
TFS-61617801-C00 1.460″ dual valve springs
TFS-61617802-C00 1.550″ dual valve springs
TFS-6161T783-C00 1.550″ dual valve springs w/ ti retainers
TFS-6161T784-C00 1.560″ dual valve springs w/ ti retainers

I know the 1.560" is intended for a solid roller up to .700" lift, but don't know what the others are spec'd for.

Somebody who actually intends to purchase the heads (or works on them for a living) is a better person to pass on this info than someone like myself who is not a prospective customer and is simply compiling info for other's knowledge base.

A dyno never has been, nor ever will be, a drag strip. It, too, is a tool to measure gains & losses which may (or may not) translate into real-world performance changes as installed in a given vehcile.

This is the question that deserves an answer - so Dwayne what would be your initial thoughts when comparing these 3 heads and which one would have the most potential out of the box and worked over?


Russ

Don't lie to us Brad, we know you want a set

Does he really need another set of dust collectors?

Yes, I do.

And, no I don't.

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I won't lie: I'd already priced it out to see what it would cost to change directions and finish putting my RB 452 back together w/ TFs, and save all my Victor stuff for my fresh RB 451 short block.

Because I've switched to a solid roller, and with having bought offset-intake pushrod lifters and the offset-intake rocker arm setup for the Victors, I couldn't do it cheaply enough to justify trying them out. Especially knowing they're still not in the same league as my CNC'd Victors, it would just be a nice "proof of concept" before putting the other parts I've already paid for into service.

So, unless somebody(s) else wants to pony up a set of heads, rockers & roller lifters to see what they can do on The MoPig, it ain't happening on my dime!

I hear you Brad, these look interesting to me, I'm just running a set of lowly OOTB (essentially) stealths, but the question is do I send them to modern for 1K and get them CNCed or pony up extra and start with the Trick Flows. Flow will be similar but a bigger port with the CNCed Stealth (not exactly sure how much bigger), will have to wait and see, and really investigate the options and the ceiling on the Trick Flows. Plus I may need another set of pushrods. And the money spent at Modern gives me a good VJ, which is sounds like the Trick Flows can use a better valve job like all of the other OOTB heads? I need plenty of other stuff for my car before I even get there though. I know you've invested WAY MORE in that Victor setup how are you doing getting past all of the hurdles?

Contact Modern for the actual price, but if you already have good springs and retainers the price is less than $1k. I just had mine done...

I did send an email, but I didn't make mention of the springs or retainers but I have changed them already. Will have to follow up thanks!

I predict that the market will soon be flooded with used Stealth heads, that'll be good for me and my aspirations.

R.

The big difference I see so far between the TF heads and the RPM/Stelth heads is the extra height. The TF heads are taller, they have longer valves and more installed height. The TF heads allow you to run .700 lift right out of the box and with a valve spring change you can run a lot more than that.

I test fitted my RAS rocker arms to the TF heads yesterday. Geometry looks just fine up to about .750 lift and then the rocker arm starts to roll towards the inside edge of the valve. Really doubt very many people are going to run that much lift.

There is enough room between the retainer and the seal to go .800 lift and the installed height is right at 2.00 inches.

What ratio RAS rockers are you testing Andy? I have a set of the RAS 1.5 and 1.6 now,(they had the first set since late last year or in January of this year) trying to decide what to do with them Now that there are some good investment cast stainless steel rocker arms availble this will probally be the last sets of ductile iron rockers I'll use

I'd definitely throw a used set on my 383 mule, so that makes 2 of us

Andy, the roller springs that come on those heads would likely be suitable for just about any roller cam I would use with them. If I were putting something together that I thought needed an .800 lift cam, I would just use bigger heads.
That Manley spring is like 900lbs open. I can't see myself opting to run that much spring with a normal shaft set up that only has five 3/8" studs holding it in place, and that much span between the studs.
I have no doubt that it won't be long and someone will put a set of these heads on something and run .800 or more lift, and make good power in the process. I just don't feel like that was the type of build these heads were targeting. I'm sure 700hp+will be easy enough to make with a pretty simple 505rb combo and a cam that would work okay with the supplied roller springs........ And that's more along the lines of what I feel is the main type of build these heads were intended for.

Only if Stealth users that swore they wanted to keep the "stock look" are willing to give that up.

I expect you'll see some Edelbrock Performer RPM heads show up for sale, too.

I'm close to ordering and have spoken to both Summit and Trick Flow Tech Lines. Both came back with same selection recommendations based on current engine build, valve train, and intended use provided. Give them a call as they were glad to be of help in making the right choice.

....and thanks for all the advice in the post