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  #16 (permalink)  
Old 06-10-2005, 03:22 PM
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454C10,

what cam would you pick ? theres a bunch of cam choices, i picked that one for the 1800 to 5800RPM Range, thats why i'm askin so i get the right combo, you help is appreciated ! what cam would you pick ?

scrol down to see cams
http://www.northernautoparts.com/Pro...uctModelId=380

i'm guessing you have a big block C10 P/U ? you have any pics ? any advice about building one ?


thanks

mustangsaly
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  #17 (permalink)  
Old 06-10-2005, 04:13 PM
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Do you need to buy it from northern? Because summit racing is cheaper for this cam. Cam and lifters for 79.95. The sum-k1104 or sum-k1105 would work for you. I like the k1105 because, like I wrote earlier, "it is a good idea to run more cam duration on the exhaust valve due to typically low flow ratios (intake/exhaust) on stock exhaust ports, plus heavy cars with small engines like more exhaust duration. (good for a truck with a 350)".

So this is know as a split duration cam which normally has more duration on the exhaust than the intake. This makes up for weak flowing exhaust ports and helps little engines in heavy cars. A how to modify a small block book will have all this information in it. You should get one at your local book store.

Yes, I have a 70 C-10. 454 cid with 8.75-9.0:1 cr, Holley 750, very mild roller cam, 781 heads with some flow work, msd ignition, cold air induction, BBC corvette exhaust manifolds, 2.5" exhaust, tachometer in factory location, 4 inch front drop and 6 inch rear drop, 1.125" front sway bar, all new bushings, 5 lug with 15x8 rallies, front disk, 3.08 with alburn LSD, 400TH, AC with 134b, power steering, power brakes, remote and power locks, 2.5" exhaust, runs mid 14's at 98 mph, 4100 lbs, 8 mpg city, 12 mpg highway, factory green but needs paint, sorry no pictures.

BBC's suck gas! The 350 that was in there before did 12/16 mpg.

My advice is to find a truck ready finished and buy it. No way my truck would sell for all the money that I have in it, not even counting the work!! I wish I had installed a used 6.0 LS1 and transmission for a heavy duty gm truck instead of the 454.
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  #18 (permalink)  
Old 06-10-2005, 04:32 PM
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i just seen northern had that cam (Plus a Bunch of Others) but i liked the 1800 to 5800 RPM, this truck will run headers, (or is there a problem with headers fitting these trucks ? ) this will be a frame off 71, i seen the truck last fall butt didn't pay much attention. what about the 10.25:1 CR i want to run ? think thats good or bad ? ( i'm thinking it will end up being a little lower than that, it's not a daily driver ) 350 turbo tranny with a stall converter with 411s..











Mustangsaly
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Old 06-13-2005, 07:32 AM
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Headers fit fine on these trucks. The problem with these trucks is getting the exhaust around the rear axle.

Well, if you are running a 4:11 and 10.25:1 cr then you should go up a little in the cam. You were talking about using a 3.73 gear before so the smaller cam would be needed in a 4000lb truck. So now, look for a cam in the 230 to 235 duration at 0.050 range (around 280 advertised). But then the valve springs become even more critical. Weak springs with a big cam really kills performance. Valve float is an ugly thing. You need the 1.5" diameter springs (dual springs). Don't use the HP Z28 springs. If you go cheap on the valve springs with this cam, the engine could be down 50hp!

10.25:1 cr with a cam in the 225 duration at 0.050" in a 350 sbc will have detonation issues. Retarded timing would be required even with the high octane pump gas. Power drops quickly with timing retard, so any power gain from higher compression is quickly lost. A bigger cam bleeds off the cylinder pressure and allows normal ignition timing.

The better choice for the street would be, 9.5:1 cr pistons along with the smaller cam (270 comp), 2200 stall, and the 3.73 gear.

Just weekend hotrodding, 10.25:1 cr, 4.11 gears, 2600 stall, 280 cam with good valve springs!.
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Old 06-13-2005, 09:16 AM
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454C10,

sorry i posted 411s butt meant 373s,(thinking one thing and writing another) with 373s in your opinion is that 1800 to 5800RPM Cam a good choice ? plus i was thinking with a starting point of 10.25:1CR, i will end up around 9.7:1 to just under 10.1:1CR or so (i'm guessing) , with head gasket & piston in the hole counted in the formula, what did you do for tail pipes ? what did you do for a fuel cell ? are you running stock height Spindles or 2" Drop Spindles ? you have a wood or metal bed floor ?

where did you get most of your body and interior and suspension parts ?

Thanks
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  #21 (permalink)  
Old 06-13-2005, 09:54 AM
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I think the 10.25:1 cr in the piston spec does include the piston down in the cylinder and the head gasket.

Yes, that would be a good cam for a 3.73. You could try the 10.25:1 cr and if it is too high then use a 2mm thick copper head gasket to lower cr.

I ran 2.5" outside the frame rails then over the axle and out the back. This clears the factory style ladder bar suspension.

I used Early Classic Enterprise's rear drop springs and shock reallocator kit.

For the front, I used 2.5 inch drop spindles plus 1" drop springs. The truck has 73 to 78 Chevy truck front suspension (a-arms, 5 lug disk brakes, sway bar, brake lines, etc). Got parts from a local junk yard and the springs, spindles, and bushings from Summit Racing. The rear axles are also 5-lug from a 73 to 78.

The truck has a metal bed (LWB) and the stock tank. I plan on building a fuel cell for myself later and will mount it between the frame rails behind the diff (20+ gallon). The rear mount fuel cells that are made for these trucks are very expensive. So I will make my own from 1/8" aluminum plate.
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Old 06-13-2005, 02:32 PM
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tell me what you think of the $250 Heads i've found for a 350cid build ?

they have 2" stainless intakes and 1 1/2 stock exhaust valves. The intake ports are gasket matched and the chambers have been polished. They have comp springs and retainers. The heads are clean as the valve job had only about 3000 miles on it. They are 76 cc chambers. They do not have screw in studs or guide plates. Casting # is 3970126.


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Mustangsaly

Last edited by Mustangsaly; 06-13-2005 at 02:37 PM.
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Old 06-13-2005, 02:57 PM
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If you're on a serious budget then those heads will work.
what is the spring diameter?
are the studs pinned?
If the studs are not pinned you need to add screwing studs. The heavy spring pressure required to runs a big cam will pull the studs out. Guide plates are nice while making high rpms.

But, those old heads just don't make as much hp as the new designs. The ports are small and don't flow well. A new set of AFR heads would make 50 more hp than those old style heads with the same parts!

If you can, get a set of 64cc trickflows, dart iron eagles, vortecs, or AFR's. The vortecs are cheapest but require some machining, special intake, special rockers, and special valve covers. But if you haven't bought any parts yet, using vortecs is no big deal.
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Old 06-13-2005, 05:08 PM
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re: heads

Just my opinion, but I don't think those heads are even worth $2.50!! Not to me anyway. 76 cc is to much. It's basically a smogger head. I think what you need for the compresion ratio you want, and for decent power would be a 64cc head with 2.02 intake and 1.64 exhaust. Also something around 200cc intake runners. I think the best "bang for your buck" would be the worlds sportsman 2 heads. both Summit and Jegs sell this head for as cheap as $879 american complete. The heads itself is $599 a pair bare. My dad purchases a pair of these before for his 350 race motor. they prove to be very good quality and you basically can't go wrong with the price. Their is room to port the intake runners if you decide to go a little bigger in you motor displacement or if you decide to turn your motor into something with more power. But the basic setup in my opinion is fine for the street aswell. I'm currently building a 327 for a street/strip car and these are the heads I personally will be using. Also, just my opinion, Their is lots of used carbs out there, I wouldn't use the quadrajet carb. Holly four barrel (or similar styles) are easy to tune and play with. sorry for running on here, good luck!
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  #25 (permalink)  
Old 06-13-2005, 05:47 PM
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454C10,

i know what your saying, i like these http://www.paceparts.com/index.asp?P...D&ProdID=24756

http://www.jegs.com/cgi-bin/ncommerc...43&prmenbr=361

http://www.primediapowerpages.com/cg...titionproducts

but i think i can make a strong street thumper with these $250 heads, those vortecs are $600+ then add intake. when my trucks ready for that serious power i will go that route and use this 350 in something else. i have plenty of other places to put my money in this truck. did you put late model stock type 3point harness seat belts in your truck ? i'm thinking of mounting or welding a seatbelt bracket in upper cab corner, and picking up some belts out of a salvage yard, might be good insurance or peace of mind with my son driving this with a 350 or 375HP motor in this SWB truck. how did running the exhaust on the outside of the frame rails work out ? did it take different headers ?

thanks

Mustangsaly
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Old 06-14-2005, 07:52 AM
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Running the exhaust over the rear axle is not a problem unless the truck is lowered. I'm not using headers so it is easy to turn the pipes quickly outwards to the outside of the frame rails. However, the pipes can always be turned to run outside the rails at any point under the cab.

Nope, just regular seat belts for me. But, I do have bolt holes in the upper cab corners already. ????

I have an idea for you..... Install a set pistons to make 9 to 9.25:1 cr with a 350 and 76 cc heads. Then install a mild cam, like a CompCam 260. This will get the truck running strong, even with the stock 3.08 gears. Good gas mileage, smooth idle, and safer hp for your son. Then you can up the hp later with 64cc heads and a cam after you have spent the money and time doing all the other things that you what to do with the truck. And will give you son time to get familar with the truck with a lower hp. FYI, good brakes, suspension, and tires will keep the truck and your son in good shape

It still would be a 300 hp engine with 350 ftlb of torque with the smogger heads and mild cam with headers. 325 hp with a little bowl smoothing in the heads.
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