Ok,
So Im reading through one of the vizzard books, and its pretty good, some stuff isnt really explained and a tad confusing but Ill get to that later.

I did some searches but didnt really find what I was looking for, so without further adieu:

--What heads would you use on a 350 thats being dedicated solely to the race track? Now narrow that list by what is cheapest, and what requires the least amount of work.

--If the budget allows, on a race engine, would a mechanical roller be the proper choice?

--What years did the strengthened lifters come in the chevy engines and what models?

--Is there a decent budget rocker that can take a higher spring pressure? Also, what are the 'good' choices for high lift rockers?


I do not have the rest of my components chosen out yet and I dont really understand the concept of making an estimate on final torque and horsepower numbers solely from the components. But I will be attempting to put together a high compression setup paired with a cam with large lift, low duration, decent overlap(not sure whether to go hydraulic roller or mechanical roller, if budget allows, otherwise it will be flat tappet).

I was thinking of the vortec head swap but not sure if those are capable of producing the numbers Im lookingfor, within my self imposed budget.

Limitations and specs of overall package:
Output: 450 hp around 6.5-7k rpm
Compression: 12-14.5:1
Budget: 2k$ overall, assuming parts can be gotten used, no issues within the assembly

Any issues with the above numbers please explain why they are not feasible and dont just flame.

Cant really think of any other questions right now so just post and If i remember, Ill add it. Also, please try and be constructive with comments, even negative ones should offer some sort of advice.


Thanks

 

Are you talking about the Vortec Fastburn heads? Those appear to be nice. Otherwise what about a set of AFR heads? I hear good things about those too.
Greg

 

I think your "budget" is COMPLETELY unrealistic.

You'd be hard put to do a STOCK REBUILD re-using YOUR OLD STOCK HEADS for that little coin. Let alone, a race motor that's going to actually win AND hold together.

Yes a roller will outrun a flat-tappet, every time. For a race motor I wouldn't fool around with anything else.

That said, if I were building such a motor and wanted to go directly to the desired results IN ONE SUCCESSFUL STEP and avoid re-doing stuff over and over because it broke or I didn't like the results, here's what I'd do:

Dart Pro1 215 heads set up for solid roller, like these http://cgi.ebay.com/ebaymotors/Dart-...QQcmdZViewItem I have no clues about this or any other seller, I'm just using the product as the example.

Solid roller cam, in the 245 - 250° @ .050", and (for those heads) slightly longer exhaust duration but maybe slightly lower lift; maybe 6° and -.025" difference

Single-plane intake; Brodix HV, Dart, Edelbrock Super Vic, etc.

1¾" headers minimum

12½:1 CR; I'd recommend flat-tops if at all possible, milling the heads down to whatever it takes for that CR; rather than domes

Enough bottom end prep to avoid scattering it after 5 runs; that would entail a non-stock forged crank, non-stock forged rods, and various block prep


I doubt you can get that combo even for $4000 though; depending on how much of it you already have. You'll need rocker arms, push rods, timing set, bearings & gaskets, MACHINE WORK, some head porting would be beneficial, etc. etc. etc.

In a word, you might want to either re-think your goal, or your budget. The 2 don't match.

 

Sofa--
quick addup new parts(not off a parts warehouse site), not really looking at specs just a REALLY fast addup:
cam 150- comp cams magnum
crank 150- scat cast
pistons 200- speed pro flats
rods 150- scat forged
pushrods 50
rockers 200- comp cams magnums
springs 50-??
rings 100- federal mogul moly
lifters 300- comp cams

thats a 1300 into the bottom end and rebuilding whatever heads are bought

that leaves a 700 for heads/intake manifold

assuming:
headers are found at junkyard
carbs im recieving are usable
I know thats missing about 500$ in random stuff(bolt kits, studs, bearings, plugs etc).

but if your not on a time constraint(which Im not) it is highly possible to find these things at a lower price, or possibly used for even less. A rebuild 'kit' with these items(pistons, rings, stock cam, rods lifters, etc) can be gotten for 200-400$, knocking a large chunk off the price of lifters, pistons, and covering the required bearings and plugs(then the other stuff that your not using can be resold and the money added back into the budget).
But the one thing not fitting into my budget currently is heads and intake manifold(intake manifolds can be gotten cheap used and likely hood of them being unusable is low).

Im trying to take my time and understand, to put together a good combination of parts and recieve a good output. I can do work on them so used parts or less than 'perfect' parts that can be gotten cheap are what Im looking for(in the way of heads and intake manifolds). Thats why I was thinking the vortecs.

Possible to do it within my budget, Yea I think so. With patience, a sense of frugality, it should be fairly simple to do it. Might require some work rather than just 'bolt ons' but I think its possible to get 450 or around there...

I do plan on having machine work done to prep the block and meet some of the specs(like getting the heads anglemilled to hit the correct CR). I also plan on doing as much as I can myself to save money in the budget rather than spending a fortune on parts and dropping them off at the perf. shop, spending an arm and a leg to have it all done for me.

I know I may seem a little optimistic, but time does make for alot of room within a tight budget....


Now that my counter rant is over, why the flattops over the domes If I may ask?

Oh and as for rethinking the goal, the budget will probably change over the time I have, to increase, initial budget is just what Im setting to get a list together to get some sort of idea what Im going for and if its possible to hit the goal with low dollar parts. Budget is not set in stone for me, but I will try and be frugal and concious of prices and keep my eyes open for used parts that fit put me on the road to my goal without breaking the bank

My main reason in listing a budget was to avoid heads that cost over 800 a pair off ebay(no afr, or new brodix/dart heads)


codename47--
both of those are nice but outside of anywhere feasible within the budget. I took a look at S/Rs and Motowns(and the other World Products heads), they can be gotten under 500 new and used.
Though, stock latemodel vortecs can be gotten for under 250 used at a junker, which was why I was thinking of them.



___________________________

Rather than whats the best heads...

Would vortecs, properly machined be capable of reaching a high output cam and meet the goal of 450 hp?(and a decent CR?)
Failing that, among the choices of world products heads or other BUDGET aftermarket heads, what would be a good candidate for the job(assuming they are worked over to meet the required specs).

 

SOFAKINGDOM is correct about the budget, but if you didnt mind used part you may have a chance, your machine work will run you at least 400-600 bucks, you can use a good aftermarket cast crank and maybe some hyper pistons, but spend some money on the rods. If all your looking for is about 450hp all you need is a good hyd flat tappet cam. If your handy with a grinder and can clearance your own block, I would look at getting a 3.75 stroke crank and make a 383, they make good reliable power and you dont have to rev them so high, wich in turn will save alot on your valve trane and make it last longer. As far as heads spend your money on your induction, thats where you make the power, maybe get a used 750 holley and buy one of those HP center sections they work pretty well, and maybe a used RACE VICTOR JR. Edelbrock makes a good 23deg head for about 1000 bucks and itS good for about 500hp according to your combo. But you will for sure need some more cash, if you could save about another 750 or so you could maybe have a pretty good engine if you just take your time and look for some deals. GOOD LUCK.

 

sorry about the long rant earlier, but sofa gave me exactly what I was trying to avoid by posting a higher budget(I can come up with likely 3-4k). But just cause I can do it doesnt mean I want to or should, Im looking for an alternative, if possible, which is why I was asking.

I do have a question to pose to you guys though, rather than a straightfoward, "will this work"...


How do you match the specs of a head with that of a cam for max output?
I did a search but didnt find anything, I think I understand head specs but Im not really sure... So I guess what Im saying is will one of you guys making a suggestion for heads explain to me how your coming up with these setups(how you match them)? is it mathematical or purely based on dyno research? if its based on the dyno is it someone elses dyno research(ie magazine or something) or your own?

Im wondering if I can get more out of this by understanding how to make a combo rather than having one of you tell me what I should do.

 

matching heads to cam: You want your complete motor to match, cam heads, pistons etc.
CR and desired RPM range basically.

So with heads-cam, lets say you want a 350, to run in 3000-7000RPM range, a high rpm type motor. So you get a big cam, lets say a comp292 or something. Now if you use a head with a 170cc intake port, that won't work well. You'll want a larger volume intake port, to support the higher flow (either higher rpm, or larger motor, both act the same in the end). So you'd want a 200cc port say.

However, if you want a smaller revving 350, 1500-5000RPM, say, more of a towing/truck/mild perf motor, 200cc heads will give poor low end power, due to bad port velocity.

I budgeted $3400 for my motor rebuild, I think i'll be coming in a bit higher, but not a lot. However, i'm only shooting for 350HP or so. Machine work is expensive.

Yes!

 

Buy yourself a 350 shorblock that is in known good condition 4-500 dollars. Take it appart and freshen it up. If you want get some of those aftermarket cheap 5.7 rods for insurance(might break your budget though). Get yourself some running good 305 higher flowing heads, get yourself the porting kit with the stones and what not. Get a book and spend alot of time reading on how to get the ports,chambers to flow very well.(it can be done with enough time) Use some steel shim gaskets and you now have a high compression motor(this is a race motor so you can only run race fuel (premium in a pinch(not to race) but timing must be reduced to about 25 total with a lazy curve and vacuum can disconnected). Put a decent size flat tappet cam in it. and you might have that 400-450hp for that budget. Oh and get some roller rockers to squeeze you to 450 or so. :-)

 

well just to let everyone know, my dad decided it would be better to have a shop we know build it so the engine was warrantied. theyre doing a sbc 400 and a th350

 

Build a 400sbc with forged flat top pistons and vortec heads. Mildly port and clean up the heads ports ( don't try and reinvent the wheel) and machine them for screwin studs guide plates and comp #987 springs. Use Manley 2.02x 1.60 stainless valves "O deck" the 400 block. use 350 5.7" rods and ARP bolts. use this comp solid flat tappet cam. Clearance grind the rod bolts to clear tthe cam after degreeeing it in on 103 intake C/L
Comp Cams #12-502-5. use comp pro magnum rockers 1.5:1. Your cr will be 12.28:1 if the 30 over block is O decked and the heads are milled about .030" to 60cc using a flat top piston Use a Edelbrock performer RPM and a 850 holley.
A good 10" 3500 stall is all you'll need. You'll make way more than 500Ft lbs and more than 450 horse on the worst day. Won't need to rev it any higher than 6500rpm. Use a 1/3/4" race header (Hooker is good)

make sure you have the car pointed in the direction you want to go when you
"Rug It"!!!
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is that a familiar combo f-bird?
12.3:1 CR? what on earth would you DO with that? run jet fuel in it???
.
.
.
ooops, you wanted that range of CR in your first post.... why?? is mixing your own gas something you want to do? I dunno, not my choice, but to each his own I guess.

 

This motor needs 110 octane fuel. Don't recomend mixing the fuel. Run straight 110.
If you want a pump gas street motor just build it the same using D dished pistons. (18-22cc)

 

I dont know what its gonna be, dad went into the shop told them what he wanted it to have in the way of power, they gave him price and they have free range within that( hes paying). They do good work though alot of the cars at the track are worked on by them, and they dont screw you out of money like some of the performance shops.

 

CONGRATS, I sure do wish I had someone to BANKROLL me.....LOL. Now take the 3 or 4 grand you can get together and make it a badass engine.....And thats great that you found someone that will warranty a race engine, Good luck with that.

 

I had to get great grades(to get the car) and to keep them up to get the engine and transmission