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Discussion Starter #1
I have an FR head and i got it decked/milled .050"
im up in the air as to which cam to get?
crower 2 has more lift then the 3's
but then i may add a JRSC in the future and the FR 3's say they are good with supercharger and n2o. also it says the rpm range is 3-8k im sure i wont go to 8k but im looking for high max power. mlbbaseball makes ma power at 7500 on his 2's? also will the head have to be milled so the cams can rotate without hitting?

Chris
 

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I have FR stage 3's in my FR head. The head is unmodified other than I installed the FR high lift valve springs. It didn't make any sense to me why they ported the head, put larger valves in and used production springs and retainers. I figured while I had it off the vehicle I might as well upgrade the springs...

I haven't dyno'd it yet since the head went on, but will be in the next couple of weeks. Wideband will be installed next week, then tweek the tune and THEN dyno tune the cams.

I have heard some people say that the FR stage 3's are not streetable, but I think the setup is great and VERY streetable.
 

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Discussion Starter #3
where do u have ur rev limiter at? and does it make power all the way to the top. stock u can feel it drop off around 5800. also do u think the fr 3's would be good with a JRSC in the future?
 

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no, they you will get blowby w/ boost, you want turbo/sc cams for boost, else, you have to dial out the overlap. same thing w/ my crowers, thas why i'm debating selling my jrsc!!
 

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Discussion Starter #5
in the description it says its good for supercharger and or n2o
 

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check out the overlap on them. any cams w/ overlap blow out boost. i don't know the FRIII specs, but i'm sure they have a good amount of overlap!
 

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i know you need better springs for the crower 2's but can you get away with stock springs with the FR 3's? does anyone know either on of the lift spec's?
 

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Discussion Starter #8
old crower 2's .374 .374
new .413 .393

FR 3's .391 .391
i have an fr head so iv got the better springs
 

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FRIII's, you can get away w/ stock, but ur springs may not last too long, they are rated at a max lift of .410" people run crower II's on stock valve trains, but i have no idea for how long.
 

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ive heard that .450" lift springs can wear your valve train out faster, is that BS?

also, ive been looking into the FR head and comp 2 combination what do you think? the comp 2's are really close to the spec's of comp 3's so i figured i would lose a little hp (hopefully a little and not a lot) and gain some driveability. consindering they are the same price, do you think that the comp 3's are streetable?

what would it be like driveing a REALLY radical cam? i mean how is it not streetable yaknow?
 

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ive heard that .450" lift springs can wear your valve train out faster, is that BS?

also, ive been looking into the FR head and comp 2 combination what do you think? the comp 2's are really close to the spec's of comp 3's so i figured i would lose a little hp (hopefully a little and not a lot) and gain some driveability. consindering they are the same price, do you think that the comp 3's are streetable?

what would it be like driveing a REALLY radical cam? i mean how is it not streetable yaknow?
 

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high lift springs put stress on valvetrain?

ive heard that .450" lift springs can wear your valve train out faster, is that BS?

also, ive been looking into the FR head and comp 2 combination what do you think? the comp 2's are really close to the spec's of comp 3's so i figured i would lose a little hp (hopefully a little and not a lot) and gain some driveability. consindering they are the same price, do you think that the comp 3's are streetable?

what would it be like driveing a REALLY radical cam? i mean how is it not streetable yaknow?
 

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It feels like it pulls all the way to my 7000 rev limiter, but my butt-dyno may need to be recalibrated. I will know better after I take it to the dyno.

I know there is someone using the fr3's with a procharger and making over 300hp so I assume the overlap is minimal, or can be dialed out with cam gears. I don't have the specs of the cam in front of me at the moment.

Also the FR head does not come with upgraded springs normally. If you look at the info on FR site it says it comes with production springs. That is why I installed the FR high lift valve springs in mine.
 

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Discussion Starter #14
the more radical the cam u make less power down low. so drive light to light on the treet u dont really go over 3500 and the cam wont make power till about 3k in WOT. so it will feel super slow and have no balls untill u mash down and hit 3-4k.
im going with FR 3's iv had two and fell zero difference in drivability.
 

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the idle is really irratic, u will have a really hard time not stalling, ur clutch pedal will become ur enemy. sometimes, you will randomly stall at the lights, and u may have to beat on ur clutch just to get going.
 

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VALVE LIFT DURATION @ .050" ADVERTISED DURATION LOBE SEPARATION
INT. EXT. INT. EXT. INT. EXT. lobe
9.9mm(.390") 9.9mm(.390") 218° 218° 240° 240° 110°

Radical Street/Strip profile. Manual transmission with headers. CNC ported head with port matched intake. Increased compression recommended: 10.5:1 - 12.0:1. Excellent power naturally aspirated PLUS super nitrous cam or with supercharger. RPM range: 3,000 - 8,000.

Is it true that if you want to use crower cams you also have to use there valve spring?
 

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you don't have to use theres, you just have to use something w/ a little stiffer spring rate. the cams push down the valves too far so they can't rebound, thats y w/ stock springs, you can get valve float at like 6k rpm where stock is at 6500 depending on how many miles ur valvetrain has. FR, ferarra, and Crower all make great valvetrains for the fofo.
 

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o, and those cams do look good for FI, or n2o, there is no valve overlap, whereas the crowers have some.
 
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