IRACE87

For those who followed this thread https://www.thirdgen.org/techbb2/sho...hreadid=249054

Here is where I am so far, please bear with me.

I changed my lifter for the comp cams 875-16 over my stockers, adjusted them at .002-.004'' preload but I don't see any differance at all. With my stockers adjusted at 1/16 of a turn preload I was able to reach 6375 rpm same with the new lifters.

Only difference is that I don't have to worry about the stock wire clip that keep the guts inside the lifters from falling off with so little preload.

Made a run tonight with my WB and need some opinion as to what is happening.
I went WOT at 3150 rpm in third gear the AFR drop to around 10.30 for 0.25 sec (pump shot) then it goes around 11.80 and goes slowly leaner until it reached 5950 rpm with 12.64 AFR.

From there it will go richer from 12.64 AFR to 10.61 AFR at 6375 rpm.

I set my bin. for an AFR of 12.5. So I know that my VE table is not perfect yet since it's richer at the lower rpm.

Two things comes to mind first is it possible that since the engine get so rich it is the reason it doesn't want to rev any higher. The funny thing is that the engine starts to go richer as soon as I reach 6000 rpm with the injectors right at 80%.(I'm still set at 12.5 AFR in PE mode at 6000 rpm and 6400 rpm).

Or the other theory is that my AFR springs # 8015 are to strong with an opening pressure 355 lbs and the lifters are squashing. That would be the reason I see the AFR rich on the WB since the valves are not openig all the way anymore. (The injectors giving the right amount of fuel at X rpm but the valves are not letting the air in anymore).
By the way I should be able to make power up to 6600- 6700rpm with my set up

Anyway thanks to anyone who took the time to read this.

PAT

Grumpy

If your doubting the ecms ability to run at that RPM, and or what your calibration is doing, an ecm bench would handle that.

At 6K RPM your basically out of time for a single coil ignition system to develope a good spark. A good CD becomes mandatory, or more coils.

11sORbust

The engine is not going to rev very well with all that fuel. Lean it out below/above 6k. Then see what happens. The a/f at WOT should never dip into the 10/11's . It will reduce your ability to rev. I thought you had that lined out (in the last thread)


I do agree with Grumpy too...

level

my maf/383 car doesn't have a problem reving to 7500rpm this is with the air/fuel ratio being off..

IRACE87

Quote:

an ecm bench would handle that.

I'm thinking about building one, I guess it's gonna be a winter project.

Quote:

A good CD becomes mandatory,

Hopefully my accel 300+ is up to the task. What is funny it seems that everyone can rev to the moon with basic set up but me.

Quote:

Lean it out below/above 6k. Then see what happens. I thought you had that lined out (in the last thread)

I'm afraid to lean it out above 6k because like I said below if the problem is related to the vavetrain I don't want to hurt anything.
My DC at 6000 rpm is 80% and at 6375 rpm is 87% DC ????? seems right ??? I thought I had it lined out but I never really see that pattern (AFR going richer) since the engine wasn't reving that high when I did most of the testing.(read shutting down at 6100 rpm).

Quote:

my maf/383 car doesn't have a problem reving to 7500rpm this is with the air/fuel ratio being off..

What kind of valvetrain do you have ??? Spring pressure ????

TRAXION

It's the heavy valves that AFR uses combined with the springs you are using. A friend went though this exact same thing awhile ago. He converted to different valves and springs and the problem disappeared. It has nothing to do with your BIN. You might have better luck on the TPI board.

Tim

MTPFI-MAF

Well Nice to see you on the boards Trax, What Brand Valves and type of Springs Would you Recommend.

I recently read a Article in a Mag Comparing a Regular Valve Springs to Comp Cams New Behive Valve Spring and the Results Were intersting, I can't Remember Which one of my supscriptions it was in.

tpep

I just had a thought. Don't mean to ask a dumb question, but how are you recording/watching RPMs? Factory or other tachometer, or datalogging software?

Reason I ask is that on most P4 ECM's I have logged, 6375 is the max RPM which will come out of the datastream. The single byte RAM variable can only go to 6375 (255 x 25 = 6375).

When you posted 6375 RPM, this is the first thing that came to my mind. But I admit, I have not read the whole thread.

todd

IRACE87

Quote:

It's the heavy valves that AFR uses combined with the springs you are using.

Are you talking about AFR stock valves because the one I have are from the upgrade kit # 8032 (valves & springs). The valves are the stainless steel 1 piece swirl polish HP they are intake part # 7002 (REV CL-1636) and exhaust # 7057 (REV CL-1632).
I have no idea how much they weight ?????

Quote:

He converted to different valves and springs and the problem disappeared.

Do you know what are the springs he used or if they had a smaller diameter, open/close pressure etc...
I will probably try new springs before I change the valves but I will have to do some research first as to what I should use.

Quote:

I recently read a Article in a Mag Comparing a Regular Valve Springs to Comp Cams New Behive Valve Spring and the Results Were intersting, I can't Remember Which one of my supscriptions it was in.

If you can find that article I would be interested to know what they say exactly.

Quote:

Don't mean to ask a dumb question, but how are you recording/watching RPMs? Factory or other tachometer, or datalogging software?

Datalogging software, and my ECM is a 730.

Thanks everyone.

PAT

Moderator: RBob you can move this thread to the TPI board also,
Thank you

11sORbust

10.3-10.6 will slow down the rate of acceleration. I didn't say that was his problem though. IMO,He should have the tune lined out before anything.....

All the 8d/730 equiped cars I have scanned displays over 6375rpms.

MTPFI-MAF

Ok the magazine is HOT ROD Sept 04' The name of the article is Valvetrain power Test page 108
I am looking for the article on their web site but with no luck yet. any ways they take a Crate ZZ454 with a Hydraulic Roller cam 211/213 Duration @.050 .510/.540 Lift that Experienced Hidous Valve Float at 5900 RPM and Well after Swaping on the Behive Springs The engine Was able to Rev farther and Didn't Experiance Valve Float until 6,600 RPM.

It says due to their Design it alows for the springs to be Lighter and also Because of design Lets the Retainers to be Lighter also.

Not to mention that the CompCams Behinve Springs had 50lbs less seat preasure and 45lbs less Pressure at max lift.

They Got My Vote!!
just my .02

JJ63

iTrader: (1)

I'm having the same problem only at around 5800 rpm. Could it be my springs?

Lunati
Installed Height 1.750"
Installed Pressure 115 lbs.
Pressure @175" 115 lbs.
Pressure @1.25" 250 lbs.
Coil Bind Height 1.080"
Outside Diameter 1.450

Hope I'm not hijacking topic.

IRACE87

Quote:

IMO,He should have the tune lined out before anything.....

The thing is that the WB shows the AFR going richer at the same time that the valve float or lifter squash or whatever is probably wrong with the valvetrain is happening.

So if let's say I have lifter squash that in itself may be the reason I see the AFR this way. Then if I change the AFR at the upper RPM for something like 13.0 and change components in the valvetrain that resolve my problem I may be way to lean after that.
I may be wrong in my theory but I just don't want to destroy anything yet. (this project took me 5 1/2 years to get where I am now)

Thanks MTPFI-MAF for the info I'll be giving a closer look at those Behive springs.

Quote:

I'm having the same problem only at around 5800 rpm. Could it be my springs?

From what I see your springs are way to weak but you should ask your cam manufacturer.

Quote:

Hope I'm not hijacking topic.

Time will tell........

Thanks

PAT

jjvette

A bad coil will produce a very poor flame which will also show up as extra fuel in the exhaust. i.e. Richer AFR's.
Don't over look the coil.
John

TRAXION

The valves that AFR uses depends on the year your heads were assembled. Their valves (exhaust particularly) weigh in the neighborhood of 115g. That's pretty hefty if you want to spin her to 6500+. The first thing that I would try is new springs. I ran CC 987 springs with roughly two 0.060" shims under each one (I say roughly because I blueprinted each spring individually ... almost all of them required two 0.060" shims in order to achieve my 140# initial and 350# open pressures). The 0.060" shims are in this link: http://www.bescaredracing.com/LEFIPC.../DCP_1917.JPG. The 987's drop right into the standard AFR spring pockets. Perfect fit. Then just slap on the correct CC titanium retainers (the stock AFR titanium retainers won't work). Great setup. While you are there make sure you swap out those crappy valve seals with a set of vitons from TEA (http://www.bescaredracing.com/LEFIPC...y/DCP_1943.JPG).

Good luck. Don't worry about the valves unless those springs still don't work. Keep in mind that I was using those springs along with the AFR HydraRev ... and my AFRs were older. I think I had better/lighter valves than my buddy who went through this.

Tim

IRACE87

Thank you TRAX for this info, I guess I will have to get a set of new springs now and cross my fingers.

Those beehive springs are really interesting I will do more research on those before I order anything. Here is a good article on the beehive springs.
http://www.babcox.com/editorial/ar/eb50354.htm

And a little pic of my set up for those interested.

Thanks

PAT

11sORbust

The beehive springs are similar to the ls1 conical spring. From what I understand they work great...

Matt87GTA

Damn Pat! That sucks that you are still having problems....

I took a look at some datalogs of mine and with Datamaster mine only shows it go up to 6375 and then it just stays there. However, with the throttle still at 100% in second gear, I pick up 10 MPH before I shift to third after it reads 6375 RPM.... And I have a Harlan shift light set to 7000 RPM right now and it will definately spin to 7k without a problem (the light comes on). It isn't exactly pulling nice and smooth and hard up there just yet as I have yet to tune it above 6k, but it does pull fairly well up there and really doesn't feel like it is running out of RPM at all even at 7k - which makes sense since mine should make peak power at at least 6500 RPM (probably more like 67-6800) and it should by no means be a peaky power curve up top given the components involved......

Yours should be pretty similar.... I think there is definately some room for improvement in the tune if you lean it out a bit.... Try just slowly working a little bit of fuel out and see if it has any affect at. If it is that rich you shouldn't have to worry about hurting anything even if you do lean it out some from what I can tell.... Might be worth a try before throwing more $$$$ and parts at it.....

I guess you have totally ruled out the lifter issues as being part of your current problem but it sounds like backing off the preload helped out some. I'm glad to hear that as there has been some debate on this issue locally. Running too much preload is definately a potential problem with setups like ours (high revers with hyd cams) and I think it is safe to say both of our engines like having very little preload on the lifters. I even tried this on a friends 396 LT1 and he picked up a solid 300 RPM with no other changes before it fell off....

As for me, I was really hoping to get back to the dyno later this month but another road course event has opened up on the 23rd for an unbeatable price and I just can't turn it down so the GTA's tune is on the back burner for now since it does drive fine. I have just been short shifting it for the most part aside from when I wanted to see how it felt up top and whatnot..... Should pull pretty good numbers now . I notice my MAP signal is always in the low 90s too and actually drops off some as the RPMs go up so I really think my air intake and TB size is hurting me too. I am looking for a deal on a 58mm currently (anybody have one and want to trade for a 52mm???? ) so hopefully that will all be ironed out before I hit the dyno as well.

IRACE87

Quote:

I took a look at some datalogs of mine and with Datamaster mine only shows it go up to 6375 and then it just stays there. However, with the throttle still at 100% in second gear, I pick up 10 MPH before I shift to third after it reads 6375 RPM.... And I have a Harlan shift light set to 7000 RPM right now and it will definately spin to 7k without a problem (the light comes on).

???? That's funny I'm using datamaster also, had my autometer shiftlite set at 6400 rpm and it came on, was seeing a little over 6500 rpm on my stock tachometer when I lifted. I wonder if anybody else seen that with datamaster.

Quote:

I guess you have totally ruled out the lifter issues as being part of your current problem but it sounds like backing off the preload helped out some. I'm glad to hear that as there has been some debate on this issue locally. Running too much preload is definately a potential problem with setups like ours (high revers with hyd cams)

There is someone for sure that knew this at comp cams since with my new 875 lifter I had to adjust them at only .002''-.004'' preload and this is just shy of 1/16 of a turn like you told me to try in the first place.

Quote:

I was really hoping to get back to the dyno later this month

Worked late at night last week to change those damn lifters hoping to make it to the dyno session that was schedule last week end, guess what..... I'm gonna have to wait....

Quote:

I am looking for a deal on a 58mm currently (anybody have one and want to trade for a 52mm???? )

Hmmmmm !!!!!! no thanks I'll keep mine.

Thanks

PAT

11sORbust

Ok, I checked my logs and the rpms does stop at 6375. You need to download the beta version of datamaster 8D. Then you can see the actual RPMs via RPM16

from datamaster beta....

92Z

iTrader: (1)

Trax,

How high were you spinning your motor with the 987 springs and titanium retainers? I just found out that i have the standard valvesprings on my AFR heads. They float around 5700 RPM. I have a 383, AFR 195's, Comp 236/242, Miniram. I'm looking to upgrade springs to get more RPM. Comp says the cam is good to 6000. Miniram good to 6500. Any info greatly appreciated.

TRAXION

My Stock AFR springs w/ hydrarev and titanium retainers could tap out at 6500. They floated somewhere around there. Once the 987's were in place the motor spun so freely. I hit off my 6800 rev limiter without a problem. A lot of people AFTER me had problems with the AFR springs and that they could only hit 5700-6000 rpms. I checked my springs and I had about the same pressures as their springs. I think the problem lies in the weight of the valves and that AFR must have switched valves somewhere. A heavier valve can make a huge difference in terms of RPM-ability.

Tim

IRACE87

Quote:

My Stock AFR springs

Tim, are you talking about the AFR # 8020 springs or the # 8015, just wondering because the heads comes stock with the # 8020 unless you ask otherwise.
I ordered mine with the # 8015.
I talked to a tech guy at AFR and he doesn't understand that I can have problem with his set up, he was convince that the problem was related to my lifters.

PAT

92Z

iTrader: (1)

Trax,

I'm interested in what springs you had also. I'm also running the Hydra-Rev kit. AFR tells me that the #8020 is a 325 lbs rate 1.45 O.D. The upgrade hydraulic roller spring #8032 is a 350 lbs rate 1.53 O.D. I pulled the valve cover and have the 1.45 O.D. springs. What lifter were you running? I'm running the Crane Cams 10530-16. Now i'm wonering if i need to change lifters also. Just trying to sort this out. Thanks for your input. BTW, my heads were purchased within the last two years or so.

IRACE87

92Z,

Just to make sure no one is confused over the part #'s and spec.

AFR-8020 1.437 OD 120# @ 1.800
.720 ID 300# @ 1.250

AFR-8015 1.530 OD 140# @ 1.790
350# @ 1.190

AFR-8032 is a kit from wich you get the 8015 springs and some different valves, the intake one is part # 7002 (REV CL-1636), exhaust part # 7057 (REV CL-1632) Those are stainless steel 1 piece swirl polish high performance valves with chrome stems. .050” Over Stock Length. They are not the valves that come stock on the AFR heads.

This is the kit I got because I didn't want to have any problem in the first place and the reason the tech guy was surprise when I told him what was happening with my engine.

PAT

P.S. By the way I do have the hydrarev kit.

92Z

iTrader: (1)

IRACE87,

O.K. I thought that the 8032 was just a valve spring upgrade. So, i have the heavy valves and the lowest rate springs. Do you (or anyone else) think that just a valve spring and retainer upgrade will cure my problem? You have the lighter valves and better springs, and you still have trouble with valve float. I'm wondering if the heads are going to have to come off to change valves also.

IRACE87

Quote:

Do you (or anyone else) think that just a valve spring and retainer upgrade will cure my problem?

First I would try to now from your cam manufacturer what is the spring rates that should be use with your cam.
One thing is for sure AFR doesn't recommand those springs on a hydraulic roller lifter set up, so better springs would be your best bet.

As for me what I now for sure is that me and Matt87GTA couldn't rev pass the 6000-6100 rpm zone with a 1/4 of a turn preload on the lifter. Now with only around 1/16 of a turn preload the engine is a different animal now, we can now rev higher.

There was something going on in the valvetrain either, valve float, lifter squash, lifter pump up ???????

Now my engine can rev higher but is straining pass 6000 rpm, that is either due to the same problem I had with 1/4 of a turn preload but with less side effect.
Or the fact that my engine is to rich pass 6000 rpm (still think that one of the above problem can make my WB read richer than it really is).
And the fact that datamaster is recording only up to 6375 rpm (the version I got) didn't help pinpointing my problem at all.

Anyway my next run will be with the datamaster beta version and I will lean it out a bit and see how the engine will react, before I spend more money on a new set of springs.

PAT

TRAXION

I was running the STOCK AFR springs (8020) ... 1.437". You don't get the better springs unless you specifically order them - and of course PAY IMHO, the 'optional' spring upgrade package should not be an option, but it is.

I agree with what was said about lifter preload. Use as little as possible. I used 1/16 of a turn.

Tim

92Z

iTrader: (1)

Trax,

I totally agree with you. AFR should know that their heads are most likely going to be used in a performance application. I think that the "8032 upgrade" should be standard on their heads. Looks like i'll be doing a spring and retainer swap, although i haven't decided if i'll go with the 987's or the beehives. The beehives look great, but WOW what a price difference over the 987's. Thanks for the input.

IRACE87

Update,
I downloaded the beta version of datamaster thanks to 11sORbust for pointing that out. Now I can see how high exactly the engine is reving. (reached 6687 rpm today easily going up a hill)

I changed the AFR in PE mode above 6000 rpm and I can see a big difference in how the engine behave (no more straining).
With all this I gained 10 mi/h in third gear.

Conclusion: - couldn't rev pass 6000-6100 rpm with 1/4 of a turn preload on the lifters. Around 1/16 was the way to go.

- Engine was straining pass 6000 rpm because it got to rich. Thanks to my WB for pointing this out. This thing was money well spent.

Now I can focus on more tuning and I can't wait to see how fast she will go at the track.

Thanks everyone.

PAT

11sORbust

nice:rockon:

jrg77

Any updates?

Damon

I've done a LOT of valvetrains for a weekend warrior and there's one thing that has always proven true about lash and valve float.

Using a very small amount of lash is a CRUTCH for inadequate valve springs. In other words, you're masking some of the symptoms, but you're not getting to the root cause.

Here's what's REALLY going on inside your engine when you experience valve float:

The lifter is NOT squashing down. It's EXPANDING and holding the valve off it's seat, killing cylinder sealing and, obviously, power. The lifter plunger expands when the valvetrain goes into "float." Contrary to popular belief this is rarely at maximum lift, although it can occur there and is more likely to do so with roller cams. Mostly it happens when the valve comes back down to rest on it's seat. The spring is inadequate to control the valvetrain at high RPMs and the valve literally "bounces" off the seat. This momentarily opens slack in the valvetrain which is immediately taken up by the self-adjusting nature of the hydraulic lifters. This is what the old timers like me call "pumping up the lifters." It happens hand-in-hand with valve float.

Now, when you use a very small lash setting what you're doing is gving the lifter nowhere left to "pump up"- it's already at the top of it's adjustment range. So you mask part of the symptoms of valve float, but beleive me, the valves are STILL FLOATING at the same RPMs they were before and you are STILL giving away power in the upper RPMs, but not quite as much.

Do as others have suggested and get some springs on those heads that are adequate for the cam you are running. A hydraulic street roller cam will typically have springs that give about 135-140lb seat pressure and about 350-375lb over the nose of the cam, give or take. A hydra-rev kit may help marginally, but don't think of it as a suitable substitute for having the right springs.

Matt87GTA

After going back to the dyno recently and seeing what happened with mine I have to completely agree.

Mine would not pull at all past 6k-ish before and now will spin to 7k+ but when looking at my power curves, and what my cam/heads/intake should produce for a power curve, there is still something wrong with the valvetrain. I have eliminated any other restriction (air intake/TB/intake/exhaust) but mine still plateaus at 6k and does not pull any MORE power after that point. It still spins and holds the 440-ish RWHP mark from 6k to 6500 or so but my combo should make its peak power in the 6500-6800 range....

I always understood the problem with my lifter preload to be lifter pump-up but I was thinking that somehow the forces involved were too much for the valvespring because of something being wrong with oil pressure building up but that really doesn't make sense.... There is no way the oil pressure behind that lifter plunger is just going to up and push the valve open. But if the valve floats and the lifer plunger pumps up and takes up that slack it will HOLD the valve open as the oil filling the lifter body cannot bleed out of the feed holes fast enough to allow the plunger to go back down to where it won't be holding the valve open anymore.

So I am thinking that valvesprings will end up having to be changed.... Which is kind of stupid since I had Brodix put in what TPIS said should work.... I haven't done any research on what I should use but I have all winter now....lol.... I also have been leaning hard towards just tossing in a solid roller since I have to change valvesprings anyways and be done with it..... Hard to say....

IRACE87

Update, I've been away from home since september for work, so I'don't have to much time in my hands right now.

Quote:

you're masking some of the symptoms, but you're not getting to the root cause.

Now I have to agree with that statement, after I changed my lifters and preload them at 1/16 of a turn I began my tuning with my WB at the higher RPM level.

First thing I found is that once I pass the 6100-6200 rpm zone the car feels like it doesn't make any more power (keep on going but not with the same intensity). At first it was pig rich at the higher rpm so I thought it was the reason it felt like this. (probably valve float is seen as rich by the WB)

I then burned a new chip to get my AFR in the 12.5-13.0 zone. Didn't change much in the behavior of the engine but I saw that at 6000 rpm I had a DC of 80%, at a higher rpm my DC was in the 74-76% zone for the same AFR so that was telling I was not making any more power past that point even if I should.

Went to the track with it and I shift around 6600 rpm, past the trap in third gear and made praticly the same ET and MPH (114) than when I was shifting at around 6000 rpm and past the trap in fourth gear. So now I'm pretty sure there is something wrong with those springs.

Quote:

Do as others have suggested and get some springs on those heads that are adequate for the cam you are running. A hydraulic street roller cam will typically have springs that give about 135-140lb seat pressure and about 350-375lb over the nose of the cam, give or take.

Right now I have 155lb seat pressure and 350lb over the nose, and everybody I talked to tells me that those are what I need ?????

Matt87GTA, sorry to see that you are still in the same boat than me. If you find a solution to your problem let me know, because me I won't be able to work on the car before christmas time.

PAT

P.S. BEEHIVE SPRINGS

Matt87GTA

Yeah, kind of sucks knowing there are still problems with the setup even with it making pretty good power. Knowing there is more potential there just kind of makes me want to find it so I can unleash it... lol.

I checked on my springs via the part number on the build sheet for my heads and they are the lightest ones Brodix has and are 140lb on the seat and 355lb over the nose. I am guessing that they just plain aren't enough for my setup for one reason or another.

I need to talk to some camshaft experts and find out what kind of limit I should keep in mind and just get the heaviest hydraulic roller springs I can get. Mine are 1.550 diameter with titanium retainers.... 2.08/1.60 valves. I wonder if the valves I am using are on the heavy side maybe..... They are the stock Brodix ones.

IRACE87

Update:

I took the engine apart and inspect every single part........found nothing wrong.

I decided to try new springs. After talking to comp cams and after seeing that TRAXION had good result with the 987's I decided to try them with titanium retainers.

Quess what I'm still having the same problem and even lost 200 rpm in third gear with 1/4 of a turn preload on the lifters. Now I can only rev to 5800 rpm. Those springs do feel differant, with the AFR springs it felt like I was hitting a wall at 6000 rpm but with the 987's there is a tell tale sign of float starting at around 5600 rpm and the engine kind of slowly stop revving any higher at 5800 rpm.

My first idea was to use the new comp cams 918's beehive springs and give them a try, but didn't like the idea of having a single spring because in case of spring failure you destroy your engine, like I've seen on some LSX engines.

So I'm now back to square one with less $$$$ in my pocket. My next winter project will probably be a solid roller cam set up because I'm really tired of this hydraulic lifter setup

PAT

jrg77

I haven't followed this completely, but the gist I get is that the issue is down to mass and a/f flow.

You are not at the beginning. You have a lot of information with which to work.

You have two different springs which you need to check the mass and spring pressure. Youmay be at the same numbers, or bought in the wrong direction.

You have valves to measure their mass. No since in buying new valves unless you know they will be lighter and at least as strong as the ones your are replacing.

And there is no information on whether you built the ecm bench.

And the lifters need to be verified that they are not pumping up and throwing off the flow.

It is time to measure and verify, not swap parts.

You might also want to try the old springs with the new retainers, if that is possible.

IRACE87

My AFR #8015 springs spec are 1.540 OD 145#@1.820 and 355#@1.250
The comp cams 987 spec are 1.430 OD 121#@1.800 and 388#@1.200

Keep in mind that I was using standard retainers with the AFR springs and now I have titanium retainers with comp cams.

I did lost 200 rpm with the comp cams springs.

So from what I can see I need springs with more seat pressure.

[This a quote from Matt87GTA that describes what is happening to me and him. The valve floats and the lifter plunger pumps up and takes up that slack it will HOLD the valve open as the oil filling the lifter body cannot bleed out of the feed holes fast enough to allow the plunger to go back down to where it won't be holding the valve open anymore.

So I know what is happening to me I just don't know how to get around that problem. The band aid fix is to preload the lifters with 1/16 of a turn but the engine will stop making any more power at the exact rpm it used to float. The valvetrain will still be unstable with less side effect.

No I can't the OD of the new retainers is to small. And usualy I should see a 200 rpm gain with Ti retainers over steel so that should in theory help me rev up to 6200 rpm with the old springs.

PAT