What is the max rev the HO Springs can handle? I figure when setting the rev limiter when it comes to tuning, the valve springs will be the first thing to let go and blow the motor on my motor build.
paul has been revving to 7500 for years. no issues (yet) *knock on wood*
BUT... you have more lift and duration. so... (honestly i wouldnt have even used ho's)
well my cams were made to be a mild drop in on HO motors....
my tuner said 7500 should be fine, but i should find out if the springs can handle 8000
IIRC, Gilles was revving to about 8000 with his HG2's.
...but like Brad said, there's more to it than just RPM. Increased Ramp rate and max lift will both decrease the max rpm before valve float.
I have no signiture
so maybe i should stick to like 7200 then?
i would... and even if they are 'good enough' im sure the bastards would wear out in no time at all.
odds are the engine will probably pull good to 7500, you'll lose some 'grunt' but you'll at least have peace of mind.
idk, what does Q4F say on the subject? i know those boys love 'risking' it.
We all need somebody to believe in something...
Yea I would love to know because id be quite pissed if I changed my springs out for a damn mild 200 rpm MORE at 7200 than I revved my Mantapart springs(7000).
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
In my opinion 7500 should be fine.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
WHITECAVY(the bash falln one) wrote:Yea I would love to know because id be quite pissed if I changed my springs out for a damn mild 200 rpm MORE at 7200 than I revved my Mantapart springs(7000).
well it depends on head flow etc but usually the HO cams make power to around 7000.
i would think the cranes would go to 7500.
We all need somebody to believe in something...
WHITECAVY(the bash falln one) wrote:Yea I would love to know because id be quite pissed if I changed my springs out for a damn mild 200 rpm MORE at 7200 than I revved my Mantapart springs(7000).
You upgraded your MantaPart springs because the HO cams would have put you at (or extremely close to) coil bind,crashing your valvetrain. I wouldn't run the Manta springs with anything bigger then the Secret Cam setup.
"The FACTS are always subject to CHANGE once the TRUTH is applied"
"In the entire history of man the only stupid questions are the ones that don't get asked"
john317(AKA Gary the Old guy) wrote:WHITECAVY(the bash falln one) wrote:Yea I would love to know because id be quite pissed if I changed my springs out for a damn mild 200 rpm MORE at 7200 than I revved my Mantapart springs(7000).
You upgraded your MantaPart springs because the HO cams would have put you at (or extremely close to) coil bind,crashing your valvetrain. I wouldn't run the Manta springs with anything bigger then the Secret Cam setup.
agreed.
full out LD2 cams would be ok to though... no bigger than .375 lift for both cams.
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Gotcha
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
so are we saying 7200 for longevity, or 7500 will hold up?
were saying we dont know. but just to be on the safe side we (or at least i am) recommending you go easy, nothing above 7200.
only like 2 people have ever used an LD9 with these cams.
We all need somebody to believe in something...
Are these OEM quad4 springs with some miles on them? New OEM springs? Napa replacements? Did you check spring pressure at open and closed heights? Your using 2.3 lifters, are they the newer, lighter style? Going by the cams profile in your mods list, they are very similar to mine. Having taken a lot of weight off my valve train by using the lighter lifters, titanium retainers and SS valves I still had issues with craptacular napa replacement springs above 7000 rpm. I think in my case, 2.3 springs of proper spec wouldn't have had a problem, even up to the current 7600 rpm limiter. The thing you should do is test them for proper pressures though. Combined with your even lighter valves and the lighter lifters, doubt youd have a problem up to or just past 7500. The big question would be if you make power up there, thats all.
13.934 @ 97.82
ALL MOTOR
i have i wanna say "Sealed Power" HO springs... i know they are advance auto part's brand.
*snip* Work internet can really be "win" sometimes!
Edited 1 time(s). Last edited Wednesday, March 10, 2010 2:14 PM
*snip* Work internet can really be "win" sometimes!
Edited 1 time(s). Last edited Wednesday, March 10, 2010 2:16 PM
makes me wonder if paul actually got HO cams or not... hes got these 'dreaded' napa springs and goes to 7500 all day long. stock 2.3 retainers, ss valves, and lightweight lifters. maybe its just a matter of time?
*caugh* (this is why i wanted the actual GM ones you cant find any more.
)
We all need somebody to believe in something...
HAHA Brad I was able to order a set and they came from my local GM dealership, there was 17 available (how????I have no clue), but the guys had them on the self with about a pound of dust lol
"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my ride." -Amen
well.. you can still get them through "GM" but at $16 a piece plus shipping i doubt anyone will want them at that price when the napa's are $80 a set.
and possibly my search was limited to just US dealers...
We all need somebody to believe in something...
I was lucky enough to get the HO springs from the dealer.
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
So the Napa replacements aren't up to spec? Has anyone tested them compared to GM HO springs?
I'm pretty sure I can test spring force at work, I'd do it if I could find a HO valve train, haha
Paying someone to install parts and bragging about it being fast, is like watching someone bang your wife and being proud to raise their kids.