468 vs 496

[hotbo]

heres what i have
100cc closed chambered heads 2.25 vavles 1.88.brodix did the heads.oval port we bought them cheap.

i run the #s on my dd and are getting very confused.
im limited to running a hyd,flat tappet.no soild roller or solid flat tappet.yeah it sucks,but hes not a mantinance guy:|err
no hyd roller either.to much money and plus i think they suck:Dlol!!!

it will be 10.1 regardless of the combination.air gap rpm intake,850 race demon{hate demons but thats what its got so be it}
normal stuff roller rockers ect.

im getting only 10-12 hp and torque by going to the 496,huh!!!!!!!!!!!!!!!!!
the flat tappet i have is a 292h 244-550 lift.i can change that but going to anything over 600 lift is a waste on oval heads that havent been heavily worked over.i have punched in everything i can find comp cams,lunati,herbert,crane,ect.nothing seems to be alot better than the 292 all within 10hp of each other never feel that!!!!
why is the 468 putting close to the same out,b/c my heads and i cant go roller,okay i type in roller sure it goes way up but remember no roller for this build so im screwed.

imo the 496 regardless of what the dd shows should be a better build,the boat is a 21ft taylor lp.it has a aggressor a/b impeller and turns 4700-4800- right now with a intake ,carb and mild rv cam,dont know specs on it.

what is your advice go 496 or stay 468.again the dd shows very litlte gain by going to the 496????????

[IMPATIENT 1]

you'll feel the difference with the added stroke;) i say the 10-12hp gain is bs. get the compression up to 11 to 1 trav, that's still safe for pump gas. 11 to 1 496 is gonna feel a ton stronger than a 10 to 1 468.

[hotbo]

you'll feel the difference with the added stroke;) i say the 10-12hp gain is bs. get the compression up to 11 to 1 trav, that's still safe for pump gas. 11 to 1 496 is gonna feel a ton stronger than a 10 to 1 468.
well tom here we go again.alot of compression is going to overcome the fact that i can only use hyd flat tappet.11.1 with cc heads would be to big of a dome have to work them over and hope it doesnt chatter:)hand

well thats what the dd sayd 10-12hp and torque bigger isnt always better the combination of parts has to work with one another,if not it will suck.

maybe the 468 will be better than the 496 b/c i cant let it breath and hell if its gonna really air out inway in a boat that heavy.im hoping it will turn 5400-5500 maybe asking to much????WITH THOSE RPM I DONT THINK A HYD ROLLER WOULD BENEFIT ANY AT ALL.
god i wish i could put solid in it.I HATE ANYTHING HYD.:)st

[cstraub]

The 496 is going to make more power I don't care what DD says. Longterm a hyd roller will be your best bang for the buck. With the Gov. controling what is going into oil formulas, the quality of some flat lifters and cam cores, you wipe one flat tappet out on initial start up you will have more then made up for the cost of a hyd roller.

[cfm]

Going over .600" won't help on oval ports ? Huh ?????

Get off the DD and use your intuition.

Use a single plane on the 496.

I've had good experiences with the marine Demon 850's.

BTW: Will be very hard to overcam a 496 with good oval's . :D

[cfm]

Ooops, I think I missed something. The heads are OEM closed chamber heads that Brodix did work on ? Or are they Brodix Oval Ports ?

[Warp Speed]

The 496 is going to make more power I don't care what DD says. Longterm a hyd roller will be your best bang for the buck. With the Gov. controling what is going into oil formulas, the quality of some flat lifters and cam cores, you wipe one flat tappet out on initial start up you will have more then made up for the cost of a hyd roller.


Need to listen to him on this!!!


We spend our life with flat tappets, and saying they suck is an understatement!!!! :)sphss
Especialy with today's oils.
As Chris said, one problem with a lobe and you have paid for the hyd roller set-up. Going this direction will cost a couple more bucks initialy, but more power and still low maintenance..nothing like having your cake and eat it too!! :)devil

I am sure he could set you up with one that fits your combo like a glove! ;)

[Bigblockbill]

I had the same thing happen to me on the DD going from 522 to 555, and even going from 9.3:1 to 11 :1 on the compression. The program only showed picking up a couple hp. I am chalking it up to my heads chocking the motor down and not flowing enough. When I increased the flow of the intake & exhasut cfm on the heads the numbers jumped way up.

As you go up in cid the heads need to flow more cfm and many times end up limiting things. I am guessing here and trowing a dart with no data to back my claim up not knowing what your intake CFM flow is bet you need more head. Try running the program with something in the 340-350 cc range on the 496 and then see where you are.

[Bigblockbill]

[QUOTE=Warp Speed;64000]Need to listen to him on this!!!


We spend our life with flat tappets, and saying they suck is an understatement!!!! :)sphss
Especialy with today's oils.
[/QUOTE}

I spend NO life with flat tappets. Had two fail a few years ago, now its rollers or nothing for me and the motors I put together. First one took out the cam and all the bearings. Second one was 2 days after I got my new boat home from CA and once again cam and bearings and a lot of work. (was probably dying even before I bought the boat) I would wager a bet at almost .600 lift its one or two in ten that don't make it. (Anyone have a better stat on this?)

If you do run flat tappets be sure and use diesel oil as it has more zinc in it.

[hotbo]

well guys i for one have broke in a ton of flat tappets and had 1 go down my fault to much pressure.i broke in 3 comps last year neah a problem:D


okay thats my point im stuck with these heads is it still worth it to go to 496 and roller?????


i have been told hyd rollers are valve dropper b/c the spring packages are to much for the shitty lifters???/thats why im on here.:Dtell me

[Hass828]

you'll feel the difference with the added stroke;) i say the 10-12hp gain is bs. get the compression up to 11 to 1 trav, that's still safe for pump gas. 11 to 1 496 is gonna feel a ton stronger than a 10 to 1 468.
Tom, 11-1 you may get away with on a shorter stroked motor with alot of overlap on the cam, but on a 496 with a small hydralic cam and oval port heads, it'll rattle its ass off on pump gas. Listen to Chris , he knows what he's talking about. Let him build you a hy roller, We've ran one in a bigblock NOS street car and it worked well, even though the heads dont flow well, if you hang the valve open longer you'd be surprised what they'd do. The 496 is going to be choked with the little heads. I'd stay 468

[IMPATIENT 1]

what are you callin alot of duration?

[hotbo]

well talked to chris on the phone:Dbrodix ix flowing 1 head next week then gotta decide whether to go flat tappet or hyd roller,if i had it my way it would be solid roller all day but its his money and boat.i told him how much for a hyd roller he shit him self maybe hell get over it,lol!!!!!!

[IMPATIENT 1]

well talked to chris on the phone:Dbrodix ix flowing 1 head next week then gotta decide whether to go flat tappet or hyd roller,if i had it my way it would be solid roller all day but its his money and boat.i told him how much for a hyd roller he shit him self maybe hell get over it,lol!!!!!!

so he's goin hyd roller? charlie's sure worked out nice on his 502.

[Hass828]

what are you callin alot of duration?
I didnt say duration, I said overlap. Overlap bleeds of compression down low and midrange , will help not to rattle , but with a hydraulic 550 lift would almost certainly build enough cylinder press. to rattle. You better consider the same on your setup if your going to run that tiny cam, dont run pump gas in that thing. Check your cranking comp. It'll be up there .

[IMPATIENT 1]

I didnt say duration, I said overlap. Overlap bleeds of compression down low and midrange , will help not to rattle , but with a hydraulic 550 lift would almost certainly build enough cylinder press. to rattle. You better consider the same on your setup if your going to run that tiny cam, dont run pump gas in that thing. Check your cranking comp. It'll be up there .

can't you say anything positive to me:D brighten my day some :D
overlap is valve timing, so what numbers are you talking about as far as overlap? io ic eo ec ???centerline?

let me hunt down my cam and i'll pm it to ya, tell me mooooorrrrreeeee

[hotbo]

from my understanding with building and caming harleys,a late intake valve closing will bleed of compression:D

tom do a compression chart kb has one on there website.it will tell you static and dynamic which is corrected after cam timing:)hand

[cstraub]

im getting only 10-12 hp and torque by going to the 496,huh!!!!!!!!!!!!!!!!!
496????????

DD does not take into effect RAM. As we grow in stroke with these engines the RAM effect is increased in the low to mid rpms. RAM is the column of air that continues entering the cylinder even after the piston has reached BDC and is on its way up and as the intake valve is closing.

As we increase stroke piston speed is increased. As PS increases the intake charge is pulled quicker into the cylinder on the intake stroke. The charge then has velocity and mass. It overcomes the piston coming up and packs more air and fuel into the cylinder.

This is why you see these low compression stroker engines with good VE%'s.

[steelcomp]

Kind of a Johnny come lately here on this thread, and I have nothing to add except to reiterate: Your oval ports will work fine on the 496. Quit confusing things in your head with DD. Have Chris Straub do the hyd roller for you, go with a single plane (Edelbrock, Dart, Team G) do what you can to get the compression no higher than 10:1 (don't sacrafice quench) and you'll have a nice running reliable engine. Show this thread to your uncle while you're at it. ;)

[hotbo]

Kind of a Johnny come lately here on this thread, and I have nothing to add except to reiterate: Your oval ports will work fine on the 496. Quit confusing things in your head with DD. Have Chris Straub do the hyd roller for you, go with a single plane (Edelbrock, Dart, Team G) do what you can to get the compression no higher than 10:1 (don't sacrafice quench) and you'll have a nice running reliable engine. Show this thread to your uncle while you're at it. ;)
i go crazy over this shit hell i am crazy:)st

i dont know what to do hes just about spent his limit.so far i have spent 2,500 on crap got nothing really.he got another 2,500 to spend tops{hes screwed}or im getting screwed looks like ill make alot f-ker!!

okay heres where im at budget built 496 with what i have.that will only leave me with about 1,300 at most.
he wants polished bolts braided hoses ect.:mad:
go hyd.roller hes screwed on the rest.go hyd flat tappet give up 50-75 hp and spend the rest on bling,{if it was mine screw the bling they cant see that when you are wot anyway!!!!!

im stuck with these heads, the air gap rpm intake is here to stay.
i can get close to my 10.1 goal and get a good tight squish.
the bad part is these heads have been set up for a hyd flat tappet that he has already paid for cant get the money outta them new springs they have 140lbs seat pressure kinda stout for flat tappet but oh well.

any suggestions.:Di think hes screwed personally:):)punch

[IMPATIENT 1]

pull shims outta the head, spend the 75 for flowin a head, get chris to cut a hyd flat for it:)bulb

[jungledave]

I built a 460 last year with an ohio crank. I went through the same decision process you are with my oval port heads. I really wish I would have went with a 4.25 stroke regardless of the heads. If you ever want to go to an aftermarket block you will already have the 4.25 crank so you have a good start on a 540. a 496 might only give 20 more hp but will give 50 ft.lbs on torque. Get a 496 crank and i'll trade you for a 454

[steelcomp]

my uncle has given me free roam on a build,heres what i have
You should delete that...;) Your uncle has one of your hands tied behind your back. He should try and understand (you should try and explain) engine internals are a buy once, cry once deal. Do it right the first time, and forget it. The bling can come at any time, little by little, or however. YOu don't build a fancy house on a crappy foundation. The people that you (not you personally) think will be impressed will be laughing behind your back.
It's easy for us to sit here and spend your money, but if you're really on that kind of a budget, you've almost already wasted more time here than it's going to be worth.
Just my sometimes never to be humble opinion.

[Hallettbutt]

I agree. You and the Uncle need to get some PM work or start mowing lawns on the weekends so you can do it right.

[hotbo]

well fellas im sorry if you feel its a waste of time,the last 496 i built for my ole man cost 12 grand very nice running mill at that.

i cant help he got fired this afternoon from a job he worked at for 25 years b/c a young foreman under him told his boss he could do his job and my uncles for less money,big fight.oil field guy.
so things have changed some.his pockets werent as deep as he thought.
i told him to start with it would be budget built,not full blown bad boy like we did on my ole mans and it really is no bad boy.:D

if you have gotten agrevatted with me okay thats fine im on here for ideas.
there is no need for him to have full forged rotating internals.so i can cut alot down there im mean he may make 550 wit this motor if lucky.he will never use nos and probably only keep this boat for a few more years,
he wants 20 plus foot pickelfork to begin with.

he has some money to spare on this thing.i can talk him into a 14-71 blower motor if i wanted.or a 600 plus n/a mill,but i dont want to milk him to death.:)hand

im sure i can say hey mark you need to go hyd roller.give me another grand plus some.then is that grand plus gonna be justified in my mind no.he said he will think about it.

i should build it put the 292h in there and let it go really b/c he will be happy i wont thats the problem.:|err

[hotbo]

oh yeah brodix wants a 150 dollars to flow 1 head:mad:thats crazy:):)punch

[IMPATIENT 1]

oh yeah brodix wants a 150 dollars to flow 1 head:mad:thats crazy:):)punch

that's about right for a big head shop. my local place charges 75 but that's 1 head only.

[hotbo]

that's about right for a big head shop. my local place charges 75 but that's 1 head only.
yeah thats 1 head only also:mad:

[cfm]

They probably have a much more sophisticated computerized flow bench than most shops.

My advice on engine build is to build it as you planned - I'm taking into consideration that his income is lost, wants to spend $$$ on bling, and the fact that using a different cylinder head is "not an option."

We do not know the person you are dealing with like you do. No where close ! As we all know, there are a ton more involved with motor build-ups then the motor itself. Personalities, $$$$$, wants, needs, expectations, half truths, misconceptions, vehicle it's going in.

It makes it easier for us (internet) to come up with a build since we don't have to deal with all those miscallaneous's.

When it comes down to general discussions on optimizing things, we can all contribute to that, but not when there are many outside factors going on.

Build it the best you can with all factors involved and we'll just hope that it all works out for you.

- CFM

[hotbo]

They probably have a much more sophisticated computerized flow bench than most shops.

My advice on engine build is to build it as you planned - I'm taking into consideration that his income is lost, wants to spend $$$ on bling, and the fact that using a different cylinder head is "not an option."

We do not know the person you are dealing with like you do. No where close ! As we all know, there are a ton more involved with motor build-ups then the motor itself. Personalities, $$$$$, wants, needs, expectations, half truths, misconceptions, vehicle it's going in.

It makes it easier for us (internet) to come up with a build since we don't have to deal with all those miscallaneous's.

When it comes down to general discussions on optimizing things, we can all contribute to that, but not when there are many outside factors going on.

Build it the best you can with all factors involved and we'll just hope that it all works out for you.

- CFM
well that was very positive my friend:D
yeah the income deal has become a issue but he is avery good fella to me and my family and like i said i could say hey mark you need hyd roller and single plain intake screw these heads bad idea you just lost alot of money i crap lets go with aluminum heads single plain roller yeah baby:)devilhe would say are you sure yeah im sure okay:)handim not gonna do it to him.

he up in the air over the hyd roller.i figured it up and he would have to give me another 1200 at least to go that route:mad:

thanks cfm and to all who has devoted time,travis