need help finding titanium springs
 

All,
I'm trying to find some place that sells lighter valve springs, but with the same strength.

I found some places (Patrick Motorsports, TurboKraft, etc..) that sells the springs, but they are a higher strength.

As I've been reading that a higher strength spring puts too much load on the cam and is only useful for engines running well above stock rpm limits, I was looking for something that provides a faster spring response to keep from floating valves, but not wear down the cam.

Any suggestions?
Thanks all for your help.

didnt know anyore made titanium springs. They make titanium retainers and locks. My motor has the eibach high pressure springs and titanium retainers and locks from Xtreem.

How high are you planning to rev it?

I don't want to go over 7500... but I do wind out the engine to the upper RPM limits when I drive.

You are confusing strength and stiffness. The stiffness of a spring, or spring rate, is a measure of the force required to compress the spring. Measured in lb/in or kg/mm. The strength is basically a measure of how much force it takes to break the part.

Thanks for clarifying it for me. So are you able to help me find a spring that has stock stiffness, or spring rate.... but is made out of a lighter alloy than the original OEM springs?

IMO, you aren't revving high enough to worry about an issue with the stock springs. The Ti springs are great for a race motor that comes apart and gets rebuilt often. For even the most serious street rod build they tend to be overkill. I am currently working on a 2.5l short stroke engine with 7500 rpm rev limit and I will be reusing my stock springs. If I spend the $$$ for titanium in my build it will be rods, where the rotating mass matters.

Thanks Matt... but I've already had to do a rebuild thanks to my valves floating.... I don't want to do that again... thus why I'm looking for springs that can keep up with the engine. Obviously the stock springs aren't doing the job.

The Eibach 911 valve springs would suffice.

Ryan

Look for lighter valves, retainers and keepers. Lighter springs are not the answer.

For what it's worth we've used the Aasco performance springs with Ti retainers on the track for years with no issues. This is with a 7k rpm limit and occasional over revs. After about 4 seasons of racing the cams had minor pitting on a couple of lobes.

I'd use AASCO springs and Ti retainers

Ti valves too if you really want to ice the cake.

Valves are definitely something I will look into, any suggestion on what to look for?

What's a good place that sells highly reliable, lighter valves?

http://www.delwestengineering.com/documents/Del_West_RTS_Catalog.pdf

perfect! thank you! Have you used them or know anything about this shop?

The Eibach springs are indeed sufficient for your intended rpm range. As the other guys indicated, the AASCO spring & retainer kit is a good one too. Been a great choice for a long, long time. So is EBS Racing's VMax kit. Kibblewhite also makes a kit for the old 911

Racing Spring Kit, Titanium, 0.540" Lift, Porsche®, 2 Valve - 911/930/964,Â*| Kibblewhite Precision Machining, Inc

But if you're not moving away from the 3.2 intake manifold, you're losing a TON of power and not able to take advantage of that increased rev limit. You also need to strongly consider stronger rods at that rpm level. The 3.3/3.3/3.6 rods are at their limit at 7000 rpm with ARP or Raceware bolts. Push them to 7500 all the time, especially a sustained duration like running to the top of 4th and into 5th at a track with a loooooooong straight and you're asking too much of those rods.

If you go with titanium valves, I believe you need to use a valve guide made of different material than the standard guides are made of. Or is it the valve seat material in the head? I forget......

They are a premier parts provider for the racing industry, I called and spoke with them about making valves for a Porsche engine.

They said they would but would need a minimum order of 16 of each to justify the tooling set up.

You might give Chris at turbocraft a call to see if he has any ideas, or see if anybody on the board wants to have some made.

Patrick motorsports might be another place to check, they do retainers and keepers but no mention of valves.

You don't need Ti springs... Get some valves with reduced diameter valve stems..valves that fit..Beehive springs.. and Ti retainers and keepers..

Well... I am planning on having my intake manifold ported & polished. I also thought about going with some carrillo rods, but some have said that the 3.2 rods are plenty strong as long as you put some ARP bolts in them.
On top of that, I am going with some 3.4 p&c and having just about everything I can be ported & polished.

Finally... I am going with 964 profile camshafts.

But you also bring up a good point... my concern is that I don't want to mismatch parts and find that getting a stronger or lighter part means that I am stressing another component beyond its limits.

We have a couple sets of the Eibach valve springs in stock if you want to go that direction.

Thanks Ryan... what spring rate are they? and what material are they made out of?

Porsche valve spring specs are at the top of page 6

http://eibach.com/sites/eibach.com.m-america/files/catalogs/evs-catalog.pdf

The imbalanced flow of the 3.2 intake isn't its only issue. Yes, having it extrude honed to balance the flow across each runner is a big help. And slightly enlarging the throttle body is a proven modification to help the engine breathe more. But the issue of power peaking is the intake's physical shape creates the limitations from an RPM standpoint. The 3.2 intake basically hits a HP wall at 6200 rpm. Look at numerous dyno plots for naturally aspirated engines, with various cams and exhaust configurations, using this intake and you'll see the HP go over the peak @ 6200 and predictably fall off beyond 6200. I'm pretty sure that condition with the 3.2 intake is what prompted Porsche to do a major redesign the intake for the 964 3.6.

My point of mentioning this is that while your engine may be able to withstand 7500 rpm, you're not really gaining anything by going there if the power isn't there. A good example of this that comes to mind is the nice engine combo JeremyD built.

http://forums.pelicanparts.com/porsche-911-technical-forum/270504-oh-dyno-we-will-go.html

He did a good job of building a complete system of stuff that worked together- Mahle 98mm 9.8:1 compression pistons, 993SS cams, good exhaust, flow balanced intake, good final tuning. Made excellent power. Look at his dyno and you'll see the peak I speak of. Go to Steve Wong's 911chips.com website or look at his facebook page and you'll see those 3.2 based engines pretty much all have the same peak around 6200 or slightly above. When you look at the dyno plots you'll see pretty much none of them go beyond 7000 rpm. Sure, they're looking for the power peak and that's why the dyno plot is terminated at 6500-7000. My point is nobody's pushing them out to 7500 to see how much power the engine is making out there because there's no benefit in going there.

Most of the feedback you'll mine from around here with respect to the 3.2/3.3/3.6 rods is cursory DIY sort of experience with them. Look a little deeper and you'll see the pros tend to shy away from them because they aren't willing to take the risk and they've seen some failures to substantiate that concern. I suspect this concern is biggest in the larger bore engines like the 3.6 with the big 100+mm pistons. The bigger the piston gets, the rod is exponentially stressed by that larger mass. In a 3.4 with 98mm pistons, maybe the loads on the rod are still in the safe zone.

Speaking of rods, if you're thinking Carrillo I would also look at Pauter. They make a really nice rod, are fantastic folks to work with in terms of support (i've sent them a few sets of their rods to be inspected and reconditioned) and they'll make whatever you specify for the price of a standard set of rods. If you're looking at lightweight this and that in the engine, they have a set of their 3.2/3.3/3.6 replacement rods that are a lightweight spec and save 30g per rod over their typical 3.2/3.3/3.6 rod. 30g is a LOT of weight savings. Or just get titanium rods like Matt said

Porsche Rods - Pauter

EDIT: And take a look at the different rods on that Pauter page. Look at the second to last column titled WT OA (overall weight). Notice how the 2.0/2.2 rods differ by SEVENTY SIX grams between standard and lightweight. The 3.0L SC style rod differ by FIFTY NINE grams. Whereas the 3.2/3.3/3.6 rods differ by only 30. That leads me to believe there's something inherently different about the sizing of the 3.2/3.3/3.6 rod that limits its strength. Seems like the big end (BE) of the 3.2/3.3/3.6 rod is not as beefy and that limits its strength? Just a broad, wild-azz assumption/observation on my part.

Great information as always!! Thank you for this.
as for the power above 7000rpm... I completely understand this... but my thought is that I'm not really looking for more power above 6200rpm, but having an engine that is reliable to wound up to 7500rpm (if needed) as fast as possible.
This will allow me to shift into the next gear with that much added power going in. In an auto-x course, sometimes I have to make a 1 second decision to either stay within a gear on a turn or shift up to the next gear. If I can wind out the engine a little longer without hurting it, it will help me maintain speed through the turn and shift up once out of the turn within a better powerband.