LONG: Faster revs, not more revs...

[pl4yboy]

Do you have any idea what the guy's name on LS1tech is?
If by 377 SBC you are referring to a 400 block and 350 crank, yes - same idea.
I consider 11:1 to be the threshold for 91 octane compression. More compression generally means more power so I figured it made sense to run all the way up to the maximum practical limit there. Also, higher compression keeps the throttle response snappy so that it doesn't "hang" at higher RPM for an undue period of time. I have also read that you can modify your IAC to help drop RPM quickly after rev up, but I don't know how that works.
I understand the logic behind the vacuum pump, but wouldn't that mean more parasitic loss to running the pump than just directly moving the crankcase air?
Yeah, 6.0 or 6.2 was considered, I guess I said Gen III but I just meant Gen III+. I had thought about a 6.0 Darton sleeved block at 4.200" bore and either a stock or (reverse) offset ground 4.8 crank. Since the RPM limit is 7,500 I think that the stock crank should hold up fine, if offset ground I am less knowledgeable on their strength limit. Also, I have no idea what rods could be used with an offset grind. Some import part in a custom length?
ITBs? What does this mean, individual throttle bores? I see from a cursory search of Google images that most images for it appear to be velocity stacks and the like...
60% underdrive - WOW. Out of curiosity, is it useless for street because of inadequate cooling from the pump running too slow, inadequate charging for the same reason, or both?
Any thoughts on the small/light/light spring vs larger (and inherently heavier) valves and springs?
What about the dog bone vs double roller timing set?
...and will the 6 bolt heads work on a 4 bolt clock or not?
Thanks for the replies guys! Keep 'em coming!

Yes, the 400 block with 350 crank setup. RetroLSx is the one doing the motors. Here's a link to his forums. They aren't very active and I don't know his exact name on LS1tech.

[Lincolnman]

Sorry for the really technical questions, that's just the way my mind is wired. I understand that the forum is intended for trucks and that this build is contrary to the conventional thinking, especially considering the weight of your vehicles. I am not a member of LS1Tech (yet) and I joined over here because I ALSO own a 1993 K3500 that will be getting a Gen III+ motor (totally independent of this theory based build). I just thought that you guys would be a good place to begin asking. I have seen Nelson's name tossed around quite a bit on the forums, and when I do my truck I will likely look to him for a tune, but this thread is about different breed of build. I will look into LS1Tech more, though. "They seem to like getting into deep theoretical discussions and there are alot of members over there that have knowledge to the point where I can barely follow what they are talking about." I have had that feeling on other forums before, I know what you mean.
ITB - okay, so that was what I was thinking I just said bore rather than body. Thank you for the video link, I will look into ITB setups more. I had kind of guessed that the 60% under drive would be totally useless, but I thought I would ask anyway.
Skeet, you have the right idea, I think. I am just trying to hammer out ALL the potential little possibilities for a "total picture" build. (STILL THEORY ONLY!)
Thanks again, guys. I'm off to LS1Tech, but I'll be back!

[Slammed96]

this thread intrigues me...mainly because I also am always having ideas on theoretical builds for my own projects and always like seeing other people's ideas. I have to say though I'm surprised nobody has mentioned using a full roller valvetrain (unless I overlooked it or it was simply assumed in use) for reduction of friction and quicker response.

[pl4yboy]

http://www.retrolsx.com/forums/


Ooops. I forgot to post the link!

[skeet]

this thread intrigues me...mainly because I also am always having ideas on theoretical builds for my own projects and always like seeing other people's ideas. I have to say though I'm surprised nobody has mentioned using a full roller valvetrain (unless I overlooked it or it was simply assumed in use) for reduction of friction and quicker response.

i was gonna mention it but i got the impression was the guy was set on hydraulic roller

good post though

[Duct_tape123]

Justin, I hate you. And he stated that he would be using a full roller valvetrain.

[Slammed96]

Justin, I hate you. And he stated that he would be using a full roller valvetrain.

hmmm...i must not have read it very well then...what i get for staying up late killin time on here

[Paulster2]

... I understand the logic behind the vacuum pump, but wouldn't that mean more parasitic loss to running the pump than just directly moving the crankcase air? ...

The vacuum pump is electric and causes no parasitic losses. I would bet every hard core racer out there is running one (or should be). It also helps the rings seal better as well.

[SCIV]

There are guys running 11.5:1 + compression, but that is on 93.

[Frenchy]

I was planning on doing this a little on the cheaper side, with a 4.8 bored out to LS1 specs. Gives you a 313, and the same bore/stroke ratio as some other revving V8s, like 289's, 302's, 340's