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EFI/N2O JUNKIE
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Sounds like my former builder, no real reason why pick up tubes not welded to pump on sbc, no reason for shaft rockers spilling its needles out, (retainers hitting, not clearanced as per instructions), then leaving needle bearings in head and pan , while off, and reinstalls with bearings , still in pan, my list goes on, wrong pistons, paid for good ones , got junk ones. I hope its not the same idiot in new jersey, alot of fucking assholes out there just assembling shit
Don't know what I will do when my guy retires..............
 

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Discussion Starter #23
What do the piston to valve clearances check out as ?
I'm not sure but I ran this set up for 4 years without issue. Then I had my heads redone, same springs, same valves, same gasket, same rockers, new titanium retainers. Geometry was the same. So I don't suspect I had any P/V issues.
 

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Discussion Starter #24
Where is this engine builder, what State. Who's cam, grinder. We have quite a few Vipers go thru the shop and all made power. So but more info and we can help some more.
Missouri and the cam was Comp Cams. The car made great power and I did have any issues for 4 years. Its only when I replaced the retainers with titanium that there was an issue. I had previous used tool steel.
 

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Discussion Starter #25
If it matters, the car was driven 500+ miles and had over a dozen dyno pulls before I got it home. I drove it home over 5 hours myself.
 

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Missouri and the cam was Comp Cams. The car made great power and I did have any issues for 4 years. Its only when I replaced the retainers with titanium that there was an issue. I had previous used tool steel.
What valve springs were used? Do the valve springs have dampers?
Flat dampers that many dual springs have will damage Ti retainers in short order.
Why the switch from tool steel to Ti?
Sounds like a foolish choice for a high mileage streeter.
Many these days are switching from Ti to light weight tool steel for street longevity.
 

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Ok got it. We usually use Comp to grind our V10 cams. Your power seems inline with what we usually get with a Gen II top end kit. Dyno pulls and milage is nothing on your deal shop has many Viper with that power that run the streets for years. Have a Gen 4 that make 688 to the wheel and he drives almost 3 hrs each way.

Now why the Ti retainers are scrapped????? No idea
 

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Discussion Starter #28
What valve springs were used? Do the valve springs have dampers?
Flat dampers that many dual springs have will damage Ti retainers in short order.
Why the switch from tool steel to Ti?
Sounds like a foolish choice for a high mileage streeter.
Many these days are switching from Ti to light weight tool steel for street longevity.
Comp Cams conical springs, part #7230. Specs below. Made it was too stiff for titanium? I asked them to use titanium. I thought it would save some weight. I guess it was a bad choice.

Max Lift: 0.665
Installed Height: 1.9
Coil Bind Height: 1.175
O.D. of Outer: 1.060/1.332
I.D. of Outer: .660/.932
Spring Style: Conical
Spring Rate: 519
Seat Pressure: 145
Damper: No
 

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Discussion Starter #29
Ok got it. We usually use Comp to grind our V10 cams. Your power seems inline with what we usually get with a Gen II top end kit. Dyno pulls and milage is nothing on your deal shop has many Viper with that power that run the streets for years. Have a Gen 4 that make 688 to the wheel and he drives almost 3 hrs each way.

Now why the Ti retainers are scrapped????? No idea
What is the name of your shop?
 

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Comp Cams conical springs, part #7230. Specs below. Made it was too stiff for titanium? I asked them to use titanium. I thought it would save some weight. I guess it was a bad choice.

Max Lift: 0.665
Installed Height: 1.9
Coil Bind Height: 1.175
O.D. of Outer: 1.060/1.332
I.D. of Outer: .660/.932
Spring Style: Conical
Spring Rate: 519
Seat Pressure: 145
Damper: No
Spring excitement will mow through a Ti retainer in a hurry, especially when using a single spring.
 

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What is spring excitement?
Every time the the valve goes up and down, the spring is exercised. Add the changing RPM of the engine and the amount of exercising over a period of time is the frequency it gets exercised - basically how many times it gets compressed per second. The frequency the spring gets exercised at is usually not a big deal until the springs nears its resonant frequency. A spring's resonant frequency is when it vibrates with excessive movement - a tuning fork is a perfect example of a resonant frequency, except a tuning fork is designed to resonate, valve springs aren't. This is known as "being excited" - the spring may be being exercised near its resonant frequency, not quite enough to be an issue with the spring but might be wiggling on the retainer enough to mar its surface. Ti isn't particularly strong so the mar, or scratch from the end of the spring which is a stress riser, gets stretched and stressed, and eventually fails. You state you have a single conical valve spring. A single spring with those rate numbers is going to be heavier than the outer spring of a dual spring system. Heavier springs typically have a lower "excitement" frequency than lighter springs, hence why Warp mentioned a possibility of what may have caused the retainers to die prematurely.
As long as the spring doesn't weight more than 100grams, you should be fine in that respect sinced your limited to less than 7000rpm..
Comp lists Ti retainers for that spring along with three other flavors of steel, hmmm....
 

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Discussion Starter #34
My titanium's have been running for years. BBC, Stainless valves, solid roller, 800# open and 8000 RPM along with a lot of street use. Something wasn't happy if they got messed up.

JIM
I know many cars that have run Ti retainers for years with no problem, but it's interesting that when I spoke with Comp Cams and Crower Cams, they both said they didnt recommend Ti for street use.
 

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If you know someone running Ti successfully, you need to get all the details of why they are successful. The old saying, the devil is in the details. How far from coil bind were the springs setup with the Ti retainers?

Just a thought - personally, it can be a problem telling a builder what to do/use (especially if he/she is not familiar with the details using the requested parts) vs letting the builder know what you're trying to accomplish and get his personal recommendation (what would he do if it was his setup for street application?) This assumes he is well versed on your setup which is why you brought it to him to begin with.
 

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Advancing the cam will take away P/V clearance on the intake valves; lose p/v clearance on the exhaust valves. Advancing the cam will ad bottom end, it will not take away HP. The cam makes the HP, the position of the installed centerline determines the RPM range where it will happen. Friend just advanced his SBC cam last weekend. It went from 106* ICL to 102* ICL in 2* increments and there was 15# additional compression at 102* vs 106*. 100* ICL lost compression; therefore, 100* was to far advanced. He will now have better bottom end times; the car will accelerate quicker which will help the front half of the track.
I guess if your racing Boneville retarded ICL would be good? I don’t know, I’ve never been there.
 
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