In an effort to justify to my self my decision to get the 4.8 insted of the 5.3. (the thory was 'Im going to do a 6.0 or 5.7 swap, save the money') Im thinking, 'why cant the 4.8 with the proper cam, valve train, and programing rev. And rev high..' The 4.8 has a VERY short stroke and the ls1 bottom end is strong. Why can't the 4.8 (with cam, valve train, and programing) rev to say 7,500 RPM. the good old chevy small block 327 could rev that high and the 4.8 has a stronger bottom end and a shorter stroke.

What do you think???

 

Several car guys have had the same ideas about the 4.8 crank. Some have enev thought about sticking the shorter crank into a larger bore block, but I have't heard of anyone actually doing it. Most of the time, the thought of more displacement wins out.

Pick up a good sized stall and get a cam with fairly big duration numbers but try to keep lift down. Look for a cam with durations in the mid 220s and lift in the .530s. Run some 918 springs (or better) with titanium retainers to keep weight down.

Look at the last two under Xtreme RPM cams:
http://www.compcams.com/information/...003/Page-3.pdf

BTW- I'd like to try the new comp 212/218 XE265HR with the XE lobes in my 5.3.

 

This is the exact project I'm going to do. I will be running a high lift cam though. 222/222 566/566 112, 3500+ stall. Gonna play with edit first for a while.


Greg

 

there are other parts that would need to be changed also. like i would get a better t-chain and the factor lifters are only good for like i think 6600 or 6800 rpms. just my .02$

 

That may be a good idea in something lighter, but in these heavy trucks, the guy with the bigger motor shifting early is gonna win every time. you also lose much more streetability with a built smaller displacement motor

 

i would love to see you prove me wrong and make that 4.8 run like mad but i am prety sure a 6.0 will be faster, less expensive and more fun to drive. 7500 sounds cool and all but wouldn't you rather be quicker and spining to 6k?

i shift at 5800 <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

yup, i agree with parish and OOsilveardo. these engines dont need to spin 99 million rpm, they need to make good low end torque to get us moving combined with nice hp (like a 400+ci solid roller 3500+ stall direct port nitrous setup for example <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> )

 

lol you guys are forgeting about me see if you throw some turbos into the equation then it is totally different

marc

 

My drag car runs ten and I shift at 5200. But my drag car has just under 500 cubes.

My evil ex-girlfriends supercharged Honda would shift at 8500 all day long and was very streetable. Low end torque is not an option on a Honda. But her Honda was well in the 13's

Then I think of the old SS Impalas, of the 60's, with the 327 that would haul ***, and they weigh just as much as our trucks.

I still think it can be done. Now if some one want to sponsor me... I'll let you all know how it turns out <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by redaddiction:
<strong> lol you guys are forgeting about me see if you throw some turbos into the equation then it is totally different

marc </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">the guy with the more mellow 6.0 with turbos would beat the crap out of you too.

Of coarse turbos would help, but it doesnt make sense to do this because you can do it cheaper and moreeffectively with a lower revving motor.

the only way you could make a high revving motor do good, would be to put a huge cam and huge converter in, and go down the whole track at 4500+ RPMs. and the guy with the more mellow 6.0 will still be right up with you, and his truck will last twice as long and get twice the mileage

theres no replacement for displacement