ap2002

iTrader: (8)

you are one of the very few on this website that thinks like that, what makes you THINK the 212/218 was not better? it would be nice for you to slap one of those on your truck and then i would like to see your opinion....

InchUp

iTrader: (2)

Here's the deal. I believe far too many members on here confuse their heavy 2-ton+ trucks they're driving with Corvettes and lightweight F-body's. Big camshafts are 'ok' in light vehicles because a lot of low end torque isn't as necessary to get the vehicles moving. It's unfortunate for this Performance Trucks website to be side linked to LS1Tech because I think too many members on here look to LS1tech for suggestions since they, themselves, aren't sure what they're after. For myself, I don't build high performance truck motors to scream past red line and pull like a banshee above 3500rpms, I plan these motors out to do what they're supposed to do; have stump pulling torque everywhere from idle to the red ticks on the tachometer just like a truck is meant for. When I buy or build a truck it's to be used for nothing else than what a truck does; offer comfortable daily transportation with enough motor to get the tough jobs done.

I completely understand some trucks can be made into sporty vehicles. Take hirdlej's newest build, for example, his rcsb 6.0L 5-speed. Now that is a fun classy ride in every way of the sense to go fast with a truck. Even so, that is still a 6.0L with what many would consider a "baby" camshaft being in the 218/224 range. While hunting down unsuspecting prey, we even toss around the idea to step down one "size" of cam to a possible 210/218 or 212/218 just to see how it feels. The same basic idea is still there though, to have a sporty truck that pulls like a bat out of hell all the way to 6500. When you've been raised up even taking your driver's license test in big block vehicles, a high winding motor just isn't appealing. hirdlej's idea to step down in cam size goes along the same thoughts; to try and make a big CID small block mimic a big block's torque curve as best as possible. This is how I build my small blocks as well.

With that said, my reasons for the XR259 vs the XR265 from Comp Cams. (206/212, .515/.522, 112LSA compared to 212/218 .522/.529 on a 114LSA) After being apart of three different Gen III V8 builds within the last 2 years, I felt confident to begin my own and had a really good idea of what I wanted. My truck is a GMC Sonoma ecsb lifted God knows how high since I stopped counting after 15" of total lift...it just doesn't matter to me anymore, I just lift to clear the tires and terrain now. It's a heavy beast compared to most S10's and Sonoma's but I'm still on-par in the lightweight category for many rcsb and ecsb Silverado's and Sierra's. I have driven many 5.3L and 6.0L trucks on a daily basis for work, so I knew what I had to do to make my 5.7L feel the same or even better. I knew from the get go that I wanted a truck's camshaft, to have immediate response when I demanded it right on tap from the 5.7L "keg" of torque. LOL, I didn't want any "boost lag" to come from my N/A motor.

I started browsing through Comp Cam's web pages looking through all the available cam cards. From my previous three partnerships in Gen III builds, I felt confident that Comp Cams was spot on the money with their rev range estimates to show what each camshaft is capable of doing within a motor. Some say 800-5800, others 1200-6000, and some way beyond 3000-7500. It is absolutely crucial to know the displacement of their estimates because a 1200-6000 rpm cam in a 5.7L is a 1400-7000 cam in the 4.8L. I felt this "proof", if you will, in hirdlej's 4.8L with the '01 LS6 cam. It started pulling off-idle and continued well past 6400-6500 and this is because the cam was originally designed by GM to be tamed by the extra displacement of a 5.7L. Since my motor is a bored over 5.3L to 5.7L, I knew the rev ranges specified by Comp Cams would be very close.

Like I said earlier, my original camshaft selection from the start was the XR265 which had an estimated range of 1200-6000 within an LS1 5.7L. As time went on before the cam purchase date I started to think about what my truck really does on a day to day basis. I drive to work and school mostly. Work is 15 minutes stop and go, school is a 2.5 hour drive one way and on top of that I often travel more than an hour to use my truck what it was designed for, off-road and hunting. I have tall 35" tires with Dana 44's at both ends in addition to 4.30 gears front and rear, a 4L60E built by me to handle the stress all finished up with a mean transfer case 4LO ratio. I realized my Sonoma was never going to wind out to 6000+ rpm's unless I was passing old grandma in her Buick on the highway, or spinning in 4LO to get myself unstuck after doing something stupid. I'd honestly say 99% of my tachometer use is below 3500, so that's where I focused my cam. When I eyeballed the XR259, Comp Cams was quoting me an 800-5800 rev range. Compared to the XR265, that means my torque will start 400 rpm's sooner (800 vs 1200) yet I'll only lose 200 at the high end should I need to stretch out the motor's legs (5800 vs 6000). For me that was a no-brainer choice then, especially since I've seen what the XR259 will do within a 5.3L. To counter the effects of the diminishing power band, I swapped heads as well from the stock 706's to milled and hand worked 241's from a Corvette after completely rebuilding the bottom end as a stock LS1. Now I get to have my cake and eat it too; massive stump pulling low end, crisp throttle response, impressive mid range, power all the way to red line, smooth idle, good gas mileage and long valve train life.

I'll admit, it took me awhile on this site to push my eyeballs back into my head from seeing all the monster camshafts being put into these little small block Gen III motors. It took me even longer to step back into reality and realize that I can't control everyone's choices, especially since we're many miles apart and I'm talking to mostly strangers. I realized all I can do is offer my two cents and give suggestions when they're asked for to hopefully give insight on a different approach to engine building. I believe camshafts are like ice cream flavors. There are so many different cams out there you just have to pick the flavor you like most. Most importantly though you (reading this), have to be 100% honest with yourself and know exactly what it is you want your motor to do. Remember, the biggest mistake a newbie makes is trying to get too much power for nothing. The result is ALWAYS a P. O. S. engine that does not run well. The bump stick is a wonderful piece of engineering within a motor, I just don't see it being the all-out performance modification so many make it out to be. I believe the bottom end, attention to detail and heads make up most of the motor. To finish with a quote, I give you this.

"The world's best cam combined with a poor set of heads will produce an engine that's a dog. But bolt on a set of great heads even with a poor cam, and that engine will still make great power." ~John Lingenfelter

InchUp

iTrader: (2)

BTW, I don't usually write that much. I'm sicker than a dog right now with nothing to do on this boring Tuesday night. Plus, that topic has been bugging me for awhile so there ya'll go.

GMCtrk

iTrader: (27)

Great post.

ap2002

iTrader: (8)

it is not unfortanately that we are related to LS1tech, we started off there and learned alot from it and still do, if you would read longer, you can see that combonations from f-bodys to truck combinations are way different, sorry that i dont write long responds like you, but i sincerely believe you give newbies alot of wrong information...... but hey thats my opinion...... and read the title of this a "performance" website, you BIG torque go big cube or get a stall/gears......

by the way i am also sick of ready some of the dumb suggestions you give... buy hey good thing is just the internet and we can speak up freely..... i just hope the newbies can read some more....

InchUp

iTrader: (2)

Wow. This thread went from picking a good cam to suit a smooth idle within the RPM range of idle-6000 to why I picked the XR259 cam to let's be all pissy to InchUp, I like it.

What puts a smile on my face is that I know I am going to keep posting the principles I do because I want other members to see different ideas on engine building. And there aint a thing you can do about it, ap2002. If you don't like what you read when I'm posting, add me to your ignore list so I don't have to see you complain when I ruffle feathers.

GMCtrk

iTrader: (27)

You stick it to him, InchUp. I approve of your posts on this forum.

JakeBrakeIH

iTrader: (22)

lol I enjoy reading your posts...I def. agree about torque being important in a truck...I mean think about it...if I got in a truck that snapped my head back right off the line I would be like holy ****...if I got into a truck that took until 3500-4000 to wake up then pull hard I dont think I would have the same effect...hard to explain I guess but if it started to pull at 3500 you only got another what, 3000 RPMs to pull hard...rather than the whole RPM range...seeing most everyone is concerned about racing I would say the hardest part is getting the big rig movin...I cant wait to see the results from hirdej's dyno results are because after what you guys have been talking about it I will probably follow a similar if not, the same build...

TXsilverado

iTrader: (19)

you have your theories crossed up a little. sure you only have another 3k to pull hard but once your up to that 3k your pulling the same amount of speed as a stock converter but you are getting there faster. it also makes shift extensions better to where when you shift your truck doesnt fall on its face for a second. a converter IS what gets the big rig moving. ive been through a few combos and the only thing to change my 60' was the converter, gears, and traction. you can waste your time with 2.20 60' times with the stock converter or dip into the 1.5-1.7x 60' times in the first sixty feet thats a HUGE difference. my rule of thumb is a tenth lost in the 60' is roughly .15 lost in the 1/4. do the math. theres your wow factor

haha this thread is funny to me for some reason. i enjoyed the novel

first of all...if denali dude is set on a 3600 converter he doesnt need to waste his time with a lil wussy cam. what inch recomended is roughly a $400 stock cam. especially in a 6.0 with a 3600 stall. im assuming our 226 cams are oversized according to inch...i just happen to be on the stock torque converter for now with my 5.7 226/226 "oversized" cam and can still burn the tires to second on drag radials. with a 3000 converter i was doing 1.69 60' times and ap is cutting 1.67 i think...good lord what a loss of down low torque! we can both only brake stall to 2200 rpm before the tires spin so that takes out the "reving to 4k rpm before putting it to the ground" lets chain them up and see who has the most grunt down low. i know where my money is at.

also i think it is great that this site is affiliated with ls1 tech. theres tons of information/EXPERIENCE for enthusiasts to read up on and get the facts straight. with tuning today what used to be considered a monster cam is a joke today.

HUH?

JakeBrakeIH

iTrader: (22)

TXsilverado, your def. right about using a stall converter...I guess what my reply was me thinking out loud about my truck being a daily driver...and seeing that many people that put cams in their truck still use there truck as a dd and not a track queen I think its silly to have your power band 3000+ and barely ever run in your power band...I know I wouldnt wanna drive a truck w/a 3000+ stall everyday to work in stop and go traffic...but hey thats just me...