already want a bigger cam

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woodsrider250

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What are the differences in gearing? The -20 probably has a locker in it. Converter makes a huge difference too. Sounds like you're where you need to be for your power delivery desires without getting into a stroker crank or going big block.
 

1low4x4

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6020 had 4:10, open diff. this truck is a 373 with a limited slip
 

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I designed my own cam using the comp cams 4X4 Xtreem lobes. I wanted peak torque to be around 3,500 with a 5,500 RPM shift point. I was intending on using a 2,000RPM stall later down the road but wanted it to also be small enough to use a stock stall. I originally ground it for a street strip S10 I was building. I thought I might be putting it in a 4X4 later down the road like I am now so that was also a factor in cam choice otherwise I would have built a lot wilder motor cuz the cost of the parts were the same. I could have had about 50 more HP for the same cost but would have lost low RPM torque. The Specs are... (Roller cam) 214*/224* @0.050 - 263*-273* - .475/.475 lift - 110LSA - 106 ICL. I ordered the cam before I had my heads machined :( I did not wont to machine them. If I would have known my springs were not going to fit and I was going to have the work done I would have went with more lift and maybe a little less duration on a wider LSA. When they machined my heads they lowered the valve guide seals and my heads don't have binding or guide interference tell .580" lift and I now have screw in studs which was not part of the original plan when I ordered the cam. This is the cam I would have ground if I would have had the heads machined first. ( 210*/220* @0.050 - 266/276 Adv - .500/.510 - 112 LSA 108 ICL ) Pretty much if I am doing a full build on a motor now I will be designing my own cam from here on out. When I build my 454 I will also me grinding my own cam for that too. Its going to be a solid lifter though and spin 6K+. Don't be afraid of tinkering with stuff. The vortecs like a wide split in duration so if you find a cam you kinda like but its not perfect than have one made. You cant screw things up too bad. If running an automatic keep the LSA in the 110-114 range and have it ground +4 ICL. The wider LSA will give you a wider power band but less total torque usually. Smooth's out the idle a little to.( Depends on set up ) If you have some killer heads than wider is some times better or if you have a lot of duration. Advancing the cam will lower the whole RPM range the cam operates in just a few hundred RPM and will increase the cylinder pressure by closing your intake valve earlier. It will also smooth out your idle a little to though. That is so weird the taller geared truck has more power. Did the other one also have a 700R4? Weight and gearing can have a slight effect on jetting needs for the carburetor so maybe the carb likes the new truck better.
 

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Thanks for all the input...the truck really does well, im not sure why the engine is so much more powerful jn this truck (k10 short) vs in my long bed c20, cam is only difference. I figured they'd be about thw same weight, one being half ton 4x4 and the other 3/4 ton 2wd. By I have no idea. In the c 20 it wouldnt Break the tires loose at all. And was not a bullet by any means. Now, in the k10, I can do a massive burn out and the truck pulls strong thru the gears. Its really nice I just want a little more with maybe a little more cam sound but without sacrificing power for noise

I know you probably want to stay with the roller cam but have you considered a Comp Cams 12-230-2 ?
 

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My cam is flat tappet.

Yeah the c20 had 4.10s but a 4L80e. All I changed in the engine is the cam and lifters but this engine is a beast in this k10 compared to the c20. Crazy, wouldn't even break a tire over in the c20 but will do a nasty Burn out in the k10
 

1low4x4

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I know you probably want to stay with the roller cam but have you considered a Comp Cams 12-230-2 ?

That looks like a smaller cam than what I have...just a lower power band
 

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All of the cams we are talking about are in the same ballpark, and are about all you can do (assuming 4bbl, dual-plane, and headers) without going to higher compression pistons or different heads. The simulated dyno curves hardly move at all.
 

1low4x4

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Well, damn. What's the next step up as far as heads go from a vortec?

Rich, does your software estimate the hp and torque produced from an engine setup once the components are typed in? Curious as to what im making and ive read that the software numbers are real close to the real numbers
 

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Don't put too much faith in the simulator. Have had a few fast motors the simulator would have told you wont work.

The difference in power is the transmissions. The 4L80 had a 2.48 first gear if I remember and the 700R4 has a 3.06 this is the great thing about the 700R4 the low 1st gear. Gearing is that important. I just replaced the 2.73 gears in my Camaro with 3.73 gears before I sold it and OMG night and day. This is why I am swapping over to an overdrive in my truck. I want lower gears in it for better acceleration and to lower my cruising RPM at the same time. Well in the end 2nd gear wont be that lower final gearing but 3rd and 4th will be closer. Swap some 4.10 or 4.11 in your truck now and it will have even more low RPM grunt. This might yield better results than a cam swap. I want to run 4.56 gears with my truck with 33s after I swap to an overdrive. I want to smoke old 5.0 mustangs at stop lights.
 

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Don't put too much faith in the simulator. Have had a few fast motors the simulator would have told you wont work.

The difference in power is the transmissions. The 4L80 had a 2.48 first gear if I remember and the 700R4 has a 3.06 this is the great thing about the 700R4 the low 1st gear. Gearing is that important. I just replaced the 2.73 gears in my Camaro with 3.73 gears before I sold it and OMG night and day. This is why I am swapping over to an overdrive in my truck. I want lower gears in it for better acceleration and to lower my cruising RPM at the same time. Well in the end 2nd gear wont be that lower final gearing but 3rd and 4th will be closer. Swap some 4.10 or 4.11 in your truck now and it will have even more low RPM grunt. This might yield better results than a cam swap. I want to run 4.56 gears with my truck with 33s after I swap to an overdrive. I want to smoke old 5.0 mustangs at stop lights.

I think you meant to say new mustangs.:)

Joe has the right answer to your question Nick. You have to remember you went from a longbed to a lifted shortbed. You dropped probably 200-205 pounds just with the bed alone. Not to mention the fact your driveshaft is probably shorter in the new truck with a lift than the old truck with the 8 foot bed. More power to the rear end quicker with less weight. :)
 

1low4x4

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And shorter exhaust!

Pretty sure he meant old 5.0....new ones are hard to beat esp in a truck lmao
 

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And shorter exhaust!

Pretty sure he meant old 5.0....new ones are hard to beat esp in a truck lmao

The old 5.0's are no slouch. I never raced one. I did race a Dodge Daytona and a Trans am back in the early 90's. We were rolling about 15 - 20 mph and hit it. These were fairly new cars back then too. Both were standard shift also. Both lost. The guy in the Daytona was pissed too. Oh well. Daytona was in town at night too. No red lights and a long run up the main drag. I thought I was going to lose my license that night too. The 406 laid the hammer down. I went around the Trans am as he was shifting into 2nd. He never caught up.:) The good old days.
 

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No my truck will not beat the new 5.0 a guy has one at work. I only am laying down around 350 HP. I do plan on spraying my motor but I don't think my 6,000LB+ truck will ever beat him. I am going to take the truck to race wars though and am hoping to hit a mid to low 14 sec quarter in my 4X4 with out the NOS. I have drove the old 5.0s and have a pretty good idea of how fast I have to be to be able to beat one. Not too hard to do but as of rite now my truck weighs 6,500 LBS. Hope to shed some weight later. Lower gears are the best way to combat the weight of a heavy vehicle if you cant put it on a diet. Gears multiply torque and torque moves weight.
 

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That's 350+ at the flywheel not the rear tires ^
 

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If your looking at new heads than pretty much anything will make more top end. It is hard to beat the low RPM power of the vortecs though. Your best bet would be to keep the vortecs and have them milled to raise compression a little. If I was to step up and wanted more power I would look at the chevy small port vortecs. There a little larger runners, larger valves, thicker deck, have screw in studs and handle more lift out of the box with out being too large of a runner for a street motor. If you want more power I would use these but would also use a slightly larger cam with them to get the most out of the swap and if your looking to just build a bad street motor and are not too worried about loosing a little low RPM torque I would get these heads, RPM air gap intake, 750 DP and a cam with about 220/230 duration @0.050 and run a 2,500 RPM stall but you would never want to tow with it again but would put you around 400HP or so. Just be good for street light runs and mud drags. I think some one on here recommended a big block to. I just picked up a good 454 for $700 that ran its whole life on propane and has never been rebuilt for my next build. Even with stock heads getting 400Hp and 500FTlb or torque is like falling off a log. For the price of new heads you could almost get a running 454 and have it in the truck. A 400 HP 454 would be very street friendly and have torque for days. Pretty much just need a cam swap and a few bolt on to get there.
 

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