3500 swap

[SappySE107]

With proper porting, they can increase flow over stock valaves. I use the stainless valves with my own angles cut on them t give similar results. I don't know what they do on a dyno though, only what they do on a flowbench.

[gectek]

but ported?

[SappySE107]

They are lighter but I dont know if they will help power wise on stock heads.

[gectek]

so are the 3500 valves that much better and lighter design to give a better increase in power when used on the 3400 heads?

[SappySE107]

Yes, they are a direct swap.

[Identity Crisis]

so let me get this straight. I can install 3500 valves in my 3400 heads?

I am using the H272 Crane Cam with the COmp Magnum Rolelr Tip 1:6 Rockers, LS6 Valve Springs.

[MidnightriderZ24]

personally what im doing is swapping in my built 3500 and just putting a 3400 plenum on it... or a 3100...

[gectek]

ok cuz i just dont want all that coolant buildup on it again when i do the swap. when i changed my lim gasket it looked like crap in there, like the carlsbad caverns...lol. lookin to change to a diff anitfreeze but cant decide which one yet

[SappySE107]

I clean it out but I don't use a die grinder on it.

[gectek]

do you clean out the coolant passage in the lim when you port(or remove casting flash and marks) or would that just hurt coolant flow and heat exchange?

[SappySE107]

You could have the cam welded and then ground if you want to dramatically change the profiles. Crane, comp, crower, lunati, most cam companies will offer a regrinding service. I am getting 2 regrinds setup tomorrow.

By the end of feb, I will have a nice setup ready for the 3500 engines.

[gectek]

ok so the larger valves would increase air flow especially at lower lifts, so i could expect alot better flow with my headers and cai. well i think the 3500 swap sounds good, and i think i would like to keep the 3400 upper, just to keep it looking stock, but switch out the springs and retainers if you offer them for the 3500 head. I guess also grinding out the seats and getting bigger vavles would be good too, just to get more ump out of it. but i really dont want much of a lope with all the porting on the heads. ill prob look at doing all this the last of feb.

so who could i get to regrind my cam? and i dont know what the LSA is stock, but obviously i couldnt change it that much from stock on my regrind could i?

[SappySE107]

I would use the lighest valve possible if you want stock size. Going larger increases the airflow, most notably at low lifts. Seats aren't a problem, as I have done this before.

[gectek]

and why would i want to go larger on the vavles than stock size, do they choke down the intake and exhaust? and would you have the seats for those, if thats what i wanted?

[gectek]

so then if i am looking for better power through the revs up to 6k rpm or higher, then should i go with stainless or the 3500 stockers, keeping it NA.