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How well will this perform?

F

Fry

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I'm planning my motor build up, doing some research to come up with a good low buck combo for a 350.
How do these parts sound?

GM Performance parts Vortec Heads (12558060) 1.94/1.5, 170cc intake runners, 64cc combustion chambers

GM Performance parts Vortec High rise aluminum manifold (12366573)

MSD HEI Distrib

Comp Cams 4x4 Cam (12-235-2) RPM Range 1000-5200, Advertised Duration IN-254 EX-262 @.050 IN-210 EX-218 Lift IN-.447 EX-.462 Lobe Sep Angle-111degree

Performance Q-Jet (not sure which one yet, mine has too many rebuilds so I'm looking into a new one)

Headers & Dual Exhaust

Obviously more parts than that but these are the performance makers, good combo? Any HP/torque guess's?

Thanks
 
Check into the pro-topline heads. Should be able to save some money. That cam has too much lift (arguably) for the Vortec springs.
 
The heads say they will accommodate a maximum camshaft lift is .475 and the cam is supposed to have .447/.462 lift.
I'm not up on my engines very well, have only ever known street engines not off road motors.
I need something that will achieve decent torque and some good hp say 300 but still get decent mileage on the long highway trips.
The vortec heads retail for around $250 which seems fairly cheap, are the pro-topline heads cheaper?
I'm open to anything, I haven't bought anything yet so I'm not set on anything.
 
I like edelbrock for a street truck but seems to not be the best combo for offroad, judging by my search on this forum.
 
Depends on what you want.

Vortec heads will force you to buy a Vortec only intake...if you have a good intake you want to re-use, that right there will save you approx. $150 over the Vortec swap.

If EGR or hot air choke is an issue, Vortec heads again cause problems, as there is no provision for te exhaust crossover needed for both in older stock setups.

The valve spring retainers are EXTREMELY close to the valve guide at just over .450" lift. Can't remember what clearance minimum is supposed to run between retainer and valve stem, but with anything over .450" lift, you are really pushing your luck when it comes to stock Vortec spring/retainer clearance specs. (I think what I read was you want .030" min. clearance there at max lift) FWIW stock Vortec cams were something quite small lift-wise, like .420", that is why these issues exist.

You can buy retrofit valvetrain stuff for new Vortecs, or you can buy heads that are just as good or better, for about the same price, and not deal with ANY of the above hassles.
 
I hate them for street too. Way better cams out there. I like my edelbrock intake and carb(love the carb actually). I've considered going to Vortecs but my motor now is fine, if I ever get new heads they will be aluminum to lose some weight.
 
Ran the setup you have in mind through DeskTop Dyno-

+/- some variables that I'm not sure about your setup, you'll be around:

2000 RPM; 78 HP...204 TQ
5500 RPM; 290 HP (peak)
4500 RPM; 295 TQ (peak)

______________________________________________

Now, I ran the same setup but changed the cam to Comp 12-206-2

2000 RPM; 136 HP...357 TQ
4500 RPM; 291 HP (peak)
3500 RPM; 365 TQ (peak)

______________________________________________

Cam changed to Comp 12-249-4

2000 RPM; 139 HP...364 TQ
4500 RPM; 285 HP (peak)
3500 RPM; 367 TQ (peak)
 
no egr, no emissions and no current intake or parts (other than pulleys and junk like that). What heads would you say for the same price?
I think aluminum is too expensive for what you get, not worth the extra $2-300.
What would a good intake be?
I was just thinking vortec since its a good price and has the right valve size for being street with decent mileage.
Maybe a guy should just step down a cam size?
Any suggestions?
I had edelbrock power package in one of my old camaros, I liked it made good, efficent power but not really what I'm looking for here.
Thanks for the help so far
 
interesting, thanks for doing that. The 12-206-2 looks appealing, a bit high on the RPM Range but sounds torquey. /forums/images/graemlins/thinking.gif
Also with a lift of .440 its closer to the range of the heads, if I choose to use them.
 
For heads I'd go with Pro Topline Iron Lightning or Pro Topline SR . The Vortecs are also a good choice, but the Toplines flow better and allow the use of standard intakes, as well as allowing higher valve lifts without machining. SDPC Vortec Heads are available with the upgrades already done, but they are a little spendy. For the intake I'd use an Edelbrock Performer. The MSD is a great distributor, but the stock HEI can be upgraded with a new module and coil if you're on a budget. For the cam, I'd stay with Comp, but I'd call their Cam Help line and ask them which one to use. Before you spend a few grand on a new motor, you might want to drop 50 bucks on Desktop Dyno 2000 so you can run combos before you spend the money. Finally, this page Dyno page has lots of combos that have been built and tested to look through.
 
I agree with most everything bowtiepower said.

Desktop Dyno is good for figuring out which cam is potentially the best for your combo, although the output numbers CAN be somewhat incorrect.

Don't forget about Crane Cams, I think a lot of their grinds are similar to Comps, but I know for my roller, Comp offered nothing close to what Crane did, which on paper anyways, is a much better grind for my application than what comp offered.
 
thanks for the links.
I don't really want to use any parts of my current 305 and would like to start fresh with a new distrib, I was also thinking maybe a summit distrib or something also.
I would like to get heads that will just bolt on since machining costs $$, so I rather not have to port or anything.
Are the Pro Topline SR the same as World Products SR heads? The SR heads in the link appear to be for a fuel injection motor, can they be run with a carb?
I was thinking maybe crate motor but I can't just go ahead and drop 3000 on a motor, dropping a couple hundred a month for a few months on parts isn't so bad though.
 
The Pro-Toplines are a better flowing head than the World heads. The PT heads are available in a variety of configurations, in this case the "fuel injection" was referring to the intake being of the 87-up bolt pattern. The pre-87 pattern is also available. On another note, GM makes a great 350 replacement Universal 350 for about $1200 that is new from top to bottom. A cam swap would really bring it to life, and you could always throw on some better heads down the road. You should be able to get this motor at your local GM dealer for a decent price to avoid shipping.
 
Yeah I seen that motor, new 4 bolt main, looks decent.
I was wondering if it would really be worth it to try and look for a 350, get it machined, buy a crank, pistons, rods, etc, I think it would be hard to get the price under what that motor is worth, and how many motors are going to be in close to new condition.
It would probably cost a guy $1000 worth of accessories to complete it but it would be a completly new motor.
Stock it has around 250hp & 300lbs/ft
Another one I was looking at was the pace I guess you could call it a do-it-yourself crate motor...
PaceParts Package
$2,427.00 PAC7353
350 4 bolt block
260 HP, 350 lbs/ft torque
8” GM Balancer
Flywheel
Oil Filter adapter
Thermostat & housing
AC Delco wires & Plugs
Edelbrock Performer Intake, Fuel pump & 600CFM Carb
HEI Distrib
AC Delco starter
ARP Hardware
Chrome GM air cleaner assembly
Needs water pump, pulleys & brackets & final assembly.
/forums/images/graemlins/thinking.gif
decisions, descisions
 
[ QUOTE ]
I need something that will achieve decent torque and some good hp say 300 but still get decent mileage on the long highway trips.


[/ QUOTE ] You just read the mind of just about everyone else on this board. /forums/images/graemlins/cool.gif
That cam should be very nice, I personally like higher lift cams for the sound and extra midrange to higher RPM HP.
With 1.6 rockers, I should be getting around 484" lift with my 406.
 
this one is pretty much my original idea isn't it?
Sounds like what I'm looking for. 325 hp, 375 lb-ft torque
p142581_image_large.jpg

http://www.chevyhiperformance.com/techarticles/71298/index1.html
 
heavy4x4 should plug that crane cam into desktop dyno and compare the numbers to some of the cams he already tested. /forums/images/graemlins/smile.gif

Those Crane numbers seem to run consistent, a lot of lobe seperation, which to my knowledge, will build a lot of cylinder pressure, which is fine with the Vortec/Fast burn combustion chamber.

The lift numbers may be a lot different between the comp and crane cams, but if they are equal, I bet the Crane looks better "on paper".
 
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