OK here is the current build (all purchased & on a delivery truck somewhere)...
Forged 408, -15cc Diamond pistons, WCCH Stage 2 Heads, 60lb injectors, Walbro 255 in-tank, Yank 3000 stall.
New cam ideas???? ;)
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OK here is the current build (all purchased & on a delivery truck somewhere)...
Forged 408, -15cc Diamond pistons, WCCH Stage 2 Heads, 60lb injectors, Walbro 255 in-tank, Yank 3000 stall.
New cam ideas???? ;)
I happen to know a guy with a big FI cam for sale. I bet you he'd make you one hell of a deal on it. Maybe trade you for broken parts. :rock:
http://www.ls1truck.com/forums/sale-...as-got-go.html
What's the compression and what do you intend on using the truck for, and is it FI or NA?
I will give him the broken parts, but the motor is going NA for now. This is expensive stuff building a new motor!!Quote:
Originally Posted by RedHeartbeat
Turbo will wait for a year, then new cam.
DD road warrior.Quote:
Originally Posted by farmtruc
NA for now, will switch cams later for FI.
CR will be 9.6 with .040" Cometics
TSP just got me their recommendation...
232/234 .595/.598 114 LSA
I would say that is pretty damn close. I like it, you will hear it lope a bit but will be streetable. I would go with it if I were you.Quote:
Originally Posted by SCIV
that sounds like a nice cam...do it! are you going with dual springs?Quote:
Originally Posted by SCIV
918's are on the WCCH already.Quote:
Originally Posted by 2k5Squirrel
well, got off the phone with Erik at HKE and he said my cam was too small. :laugh: COMP CAMS 54-448-11 GEN III/LS1/LS6 350 XTREME XE-R XER287HR CAM FasterThanThem.com
He says this is a nice safe/sane cam for a 408 :eek:
I seriously doubt that :lol:
He said my engine needed about another .060" lift and another 20 degrees of duration plus it should be indexed 4* positive. Right now it's only +1. He says I'm easily leaving 50 HP on the table using this current cam.
Quote:
Originally Posted by SCIV
I hope your not gonna run the 918 on that cam you just described.....did I read that wrong.
I wouldnt consider going over 590 lift with those, they are only good for 600 and you have things expanding and contracting in there.....might check that out. I could be wrong to! I did have a comp represenitive tell me not to run the 918's on a 581/588 cam.....so n e way I hope this helped you or keeps you from breaking something.
jarrod
So you are saying that Comp 918's which are claimed to be good to .600 lift, are NOT good to .600 lift???
What kind of :bs:am I getting sold here?
What should I use, the 921's? If that is the case, then I will probably go with TSP's 1st cam recommendation...
233/239 .595/.603 114 LSA
EDIT - Forget the 921's...I just saw their price!! What should I use?
I ran my old cam with the 918s and it was not an issue at almost .610 lift.
Just an fyi, we've used the 918's on big cams before, they work fine. Actually, I would rather use the 918's over any dual springs anyday for a semi daily driver, we don't experience any valve float, we have had one break, yet, and the combination seems to make the valve train quiet.
SC, we put a 240 cam in a daily driver GTO, 408, it runs great.
Then how about that cam? 233/239 .595/.603 114
I don't want to ruin a $5,000 setup over a $100 part; you know what I mean?
FWIW, Erik at HKE says to run the springs shimmed close to coil bind. He expressed concerns about my Patriot springs and is shimming the springs up .060" to the way he prefers them. He told me that if I were to ever replace the heads, contact the manufacturer of the head and tell them how much lift I planned on running so that the springs could be setup to their specs. He recommended not buying off the shelf heads unless you're going to have them shimmed properly. I think he said that he likes them shimmed within .050" of coil bind.
Hmmm...Quote:
Originally Posted by RedHeartbeat
I really don't understand how running them closer to bind is better?
Yeah, I don't quite understand it either but he's the one building 408s turning 9000+ rpm so I'll let his opinion stand on this small issue. :D
It's supposed to prevent valve float.
What max RPM?Quote:
Originally Posted by RedHeartbeat
6500 is where mine was set
how about my stock 4.8 turning 6700 RPM's...should i change my chit or don't worry about cause it's a lil 4.8
I think the 4.8 might make a difference. But what do I know, I am on here asking questions like crazy.
got it brother....that's a lot of money. don't want to mess it up going to the 7-11 for a slurpeeQuote:
Originally Posted by SCIV
Quote:
Originally Posted by RedHeartbeat
that sounds right!!!!
.050 from coil bind, this is extremely safe. But you can only shim tighter, unless he cuts the spring pockets to let them drop down....this being said....918's are good for .600 and the cam he wants is .602 or something so that means he is in coil bind by .002.....when turning high rpm's, something could very well break!!
SCIV
If you are dead set on running the 918's then I would stay at .588 or lower, if you are wanting to run the .602 lift then I would definately go with a double spring capable of .640 or .650. The key here is to help you from breaking something. I have built several engines and all to which I wanted to be able to beat the crap out of and luckily I have been successful. Allen did say that he would run the 918's on a big cam but he didnt say anything about exceding the max lift that the springs were capable of. They are a great spring and I went with them myself...my cam is a 228/230 585/585 on a 112.
I know this is just a forum and its hard to take advice from people so you can decide what you want to do, but either way I hope I helped you out. Your springs will also stay stronger longer if you arent at the max lift of the spring.
Hope that all made sense, shoot me an email and I can give you my telephone number. maybe I cqan help you out over the phone. jasdan86@hotmail.com
Thanks everyone.
I am leaning towards a 228/232 .585/.588 112
Quote:
Originally Posted by SCIV
that sonds like a winner.......You will like being able to purchase the affordable 918's with that as well. That is almost identical to my cam, it seems to be really drivable and have a real nice lope. I dont feel the cam as im driving at 60 like i thought i would. Hope you like it to.
jarrod
Shimming the springs puts more tension on them. As you shim the spring more the stiffer it gets, so shimming it as close as possible to the maximum compression point of the spring puts the maximum amount of tension on the spring to prevetn valve float. The bad thing about doing that is that it wears out sprigns faster and causes a slight loss in HP due to valvetrain friction. Also carfreak before you post stuff about these springs make sure your facts are straight and scare SC into thinking he has the wrong springs for his cam. By doing the calcs with the info provided I get on Comps website I get a theoretical coil bind of .638". Now you wouldnt want to run it that close due to lifter hop(possible), coil deformation(@high rpm), and lifter plunger movement. Even on TSPs website it says .625 lift which would be about right when you factor in everything I listed above. Here is the link
Comp Cams "918" Stock-Diameter Replacement Springs
SC, I think the 228/232 cam is better decision lift aside, it will net you a very nice driving truck and will come out of the hole HARD on a 3K stall.
Quote:
Originally Posted by 1slow01z71
you said get my facts strait but you stated the same things I did!!! Maybe you should read my comments a little closer....pushing the springs to their limit is hard on the valvetrain just as we both stated....i was quting someone else's opinion on shimming the springs...so before you go bashing on me maybe you should read a little closer!
direct quote from one of your posts above, the link I provided shows they are good for .625 and theoretical coil bind at .638 by doing the calcs, maybe you should read what you posted;)Quote:
Originally Posted by carfreak07
Nobody wins. Upward and onward. Gaining no ground going around in circles here.
The point is people post misinformation rampant on these internet forums and it was almost enough to make SC buy new springs or make a decision on a different cam because someone posted the wrong info. Thats my point not that Im right. People just need to check their facts more carefully.
Quote:
Originally Posted by 1slow01z71
tell you what....just give comp a call and see what they have to say about running a .600 lift cam on their 918's....i wasnt posting wrong information, I was posting information to keep him from breaking another engine. You shouldnt guide others in a direction that you have no clue about.....reading only gives you info, doing so gives you experience.....which have you been doing???
Whatever man, its like arguing with a fence post, tons and tons of people have ran more then 600 lift and been totally fine, a big company like TSP wouldnt say they are good to 625 if they werent. Ask Allen to what lift he uses 918s to, its over 600;)Quote:
Originally Posted by carfreak07
Thanks everyone for the concerns and input. I weighed everything and spoke with numerous people before deciding on what I went with.
Thanks again.
S.C.