Sinister_Z28

Ok so up until yesterday i hadn't even heard of Ballistic Speed or there small bore ls3 heads. Has anyone ran these heads or know anything about them like if they are legit. Because they seem too good to be true. Now what about the GMPP small bore ls3 heads? They seem like a decent budget type head but there flow numbers look super low. Anyone run the GMPP small bore heads? And does anyone do good port work on them? Thanks in advance guys.

LS1MCSS

iTrader: (18)

Go to their site and add good springs to the stage two head option. It looks like you can get a much better flowing head for about $100 more money.

Sinister_Z28

Ur talking about the Ballistic Speed heads right? Is Ballistic Speed considered a trusted company here on tech because ive never heard of em so i was wondering if any of u have.

Sinister_Z28

Oh im considering these heads for my 408 if that helps

Jimbo1367

TEA TFS 235 or AFR 230s would be my choice fort a somewhat small bore engine. AI TFS is also worth checking into. AI's DARTs is a good choice if money is getting tight.

Sinister_Z28

Im wanting to stay square port because thats what i am already set up for and i dont wanna spend 4k to go back to cathedral port. So has anyone ever used or seen any results from GMPP small bore LS3's?

KCS

iTrader: (20)

I've seen some results from some ported GMPP small bore LS3's and they were worse than a stock set of LS3 heads, however, the cnc ports were questionable at best. The bowls were blown out and the cnc cuts were pretty rough. It definitely looked like a mass produced CNC port and not a good quality job.

Ballistic Speed seems to be relatively new, and nothing I've read would make me think anything bad about them. It seems all they do is take the stock "as cast" LS3 head and cut the seats to use smaller valves and that is the Stage 1. There are results posted, and as expected, I think the 383ci results were pretty good, but on the 346ci engine, they seemed to be kind of a dog. I think it may be too much for a 346ci engine, but you can probably bandaid that with the cam specs and/or manifold sizing.

DietCoke

iTrader: (18)

they're just procomp chinese castings. nothing wrong with them. port velocity is slow for a 346

KCS

iTrader: (20)

How long ago was that?

KCS

iTrader: (20)

I want to say it was around early to mid 2012. The heads were supplied by someone else, who is pretty well connected as far as getting parts, so I'm not 100% sure where he had gotten them from.

Sinister_Z28

So the Ballistic Speed Stage 1 small bore ls3's did alright on a 383 so how good do u guys think a set of there stage 2 heads would do on my 408? Also is it even worth trying to find good set of small bores or should i just run ported LS3 castings?

KCS

iTrader: (20)

Ballistic Speed states they use GM castings, not ProComp.

KCS

iTrader: (20)

Either option should do well depending on who ports the heads, but between the two, I probably wouldn't mess with the small bore heads on a 408. You have enough bore for that 2.165" valve IMO, but some people would disagree.

Sinister_Z28

So what head would make more power, a LS3 head with a 2.165" valve on a 408 or a ls3 head with a 2.000" valve on the same 408. Also both heads would have the same port work and what not. Also when does valve shrouding come in to play.

KCS

iTrader: (20)

Those are all loaded questions and you can ask 10 people and get 10 different answers. The Ballistic small bores use a smaller 2.08" vs the 2.165". On a 4.030" bore, cammed appropriately, there probably won't be much of a difference, but I would think the bigger valve could make more power.

Sinister_Z28

I see where ur coming from. So will a 4.030" bore shroud a 2.165" intake valve? Also why do most people say LS3 heads dont make big power on a 402/408? Is it because people dont set them up right?

Sinister_Z28

That makes sense.

Sinister_Z28

So if ballistic Speed just changes the intake valve couldn't some one do that on there own and have someone like AI port the head or does changing the intake valve require crazy machining?

briancb1

okay explain whats the typical wrong way to set up a 408 LS3... and whats the right way?

Sinister_Z28

Im not trying to say people are wrong and right. Im just trying to figure out what i think is the right way to set up my 408. It just seems like all the 408 builds with LS3 heads all make very similar power and im trying to do it different. Like i said im not trying to say there is a right and a wrong way to do a LS3 408 im just researching what i think is the " Best Way For Me" to set up my 408.