3.73 to 4.10's worth it?

[SUX2BU99]

I would look first at your carb. You bought it used but do you know how it is calibrated? I had a HUGE difference in part-throttle performance once I dug around in my carb and changed some things. First thing I found was one of my accelerator pump nozzles was plugged. Fixed that and went with the next step up one. Then I adjusted the hole that the pump arm was using, that also made an improvement. Then I bought an Edelbrock carb tuning kit and found that my carb had the lightest springs in it on the metering rods, which also choked power. Before I bought my truck the guy tried to get it through emissions so I think they totally leaned it down. I stepped up the springs and went one size thinner on the rod and my truck is a different animal now. And it's way easy to do on those carbs. Changing the jets is a bit of a pain as you have to remove the top half of the carb but not a huge deal. Look into that and where your timing is and you might see great results.

[westsidek20]

So i posted a few weeks ago about changing 3.73 gears to 4.10's, and most of you thought that i radder swap the thumpr cam (i don't recommend to any one!) to something that gives me more torque, to be able to move faster from the stop... my truck isn't able to smoke the tires!!
Its a 78' K20 with a 383 has 170cc runners, 67cc World S/R Torquer heads, 2.02/1.6 valves, Roller tip 1.52 rockers, 600cfm,
Flat head pistons, Edelbrock RPM intake, MSD ignition system, 14 FF Rearend with 3.73, 16.5x33x12.50 tires.

So now that i made the mistake of putting a "thumpr" cam, its soo slow from a stop, i beg for your input on this, i want to get the right cam for the truck, i want it to be faster from a stop, mostly street driven, light offroad, no towing.

I filled out the Compcams Camshaft recommendation Request with all my info, and they suggested the XE268H, Xtreme energy Hydraulic Flat Tapped Cam, the specs:

RPM Range 1600-5800
Lobe sep 110
Lift@.050  224/230
Intake Centerline 106     Valve lift .477/.480

Does any body here have any experience with this cam? or comment on it?
Any other suggestions??

[codyC10kid]

comparing that cam to My cam I'm gunna buy(I'm getting a extreme 4x4 from comp) your cam you listed is just a lil bit better than mine.and they said mine is good for low to mid range torque witch will get you moving....So id say that would be an alright one to go with

[bake74]

     There are only a few people here that have built alot of engines.  Do you have a speed shop or racing shop near you. 
     You are asking for specifics from most on here who have 1 or maybe 2 differnt try's at different componets in a engine.  A speed shop or racing shop who have built hundreds and done the experimenting would be able to help you better, then you should ask questions on here about what they recommend.
     I don't build engines, but that is what I plan on doing when I get to the engine on my build, I am looking for a specific engine to do a specific job, so I figure talk to the ones who do it for a living, then ask advice from the hobby crowd.  Just my thoughts.

[454Man]

So i posted a few weeks ago about changing 3.73 gears to 4.10's, and most of you thought that i radder swap the thumpr cam (i don't recommend to any one!) to something that gives me more torque, to be able to move faster from the stop... my truck isn't able to smoke the tires!!
Its a 78' K20 with a 383 has 170cc runners, 67cc World S/R Torquer heads, 2.02/1.6 valves, Roller tip 1.52 rockers, 600cfm,
Flat head pistons, Edelbrock RPM intake, MSD ignition system, 14 FF Rearend with 3.73, 16.5x33x12.50 tires.

So now that i made the mistake of putting a "thumpr" cam, its soo slow from a stop, i beg for your input on this, i want to get the right cam for the truck, i want it to be faster from a stop, mostly street driven, light offroad, no towing.

I filled out the Compcams Camshaft recommendation Request with all my info, and they suggested the XE268H, Xtreme energy Hydraulic Flat Tapped Cam, the specs:

RPM Range 1600-5800
Lobe sep 110
Lift@.050  224/230
Intake Centerline 106     Valve lift .477/.480

Does any body here have any experience with this cam? or comment on it?
Any other suggestions??

Back when I was dreading for a truck I can across a truck with that cam.sounded pretty good, but it had a 2000 stall convertor in it, thing got off the line darn good

[SUX2BU99]

As I was reading your description and the motor details I thought to myself "Hmm, the XE268H that I have would probably work well for him and then I see that's what Comp recommends! I really like that cam and the 268 grind has been a workhorse for Comp. It seems to work well in most milder street applications. I have a 3.40 rear end but shorter tires but otherwise a somewhat similar setup to yours. My truck before the cam, heads and rear end change could barely do a brakestand. Now if I am rolling at about 15 mph and stomp on it, it will light up the tires and spin them into 2nd gear too. My truck being a 2wd shorty is lighter than yours but even still, your combo with that cam and a well-adjusted carb and distributor should get the tires spinnin'!

[VileZambonie]

First, Why start a new thread on the same issue with the same ride? Second, you say you have a thumpr cam which tells us absolutely nothing specific about the cam. You need to post the specifications and how you installed the cam (timing).

Now before you do anything else, tell us about your ignition system and how you have your timing set.

[westsidek20]

sorry for starting a new thread, its just that i thought that the initial post isn't the topic anymore, and wanted to get as much feedback as possible.
The thumpr cam's specs:
Operating range 2000-5800
227-241 at .050
471-456 at 1.5:1
107 lobe
I do have a B&W torque master 2000 stall in it.
The ignition system is MSD Streetfire dizzy, 6AL ignition box, wires and plugs.
I appreciate all your help.

[VileZambonie]

No need to be sorry but if there's more information available then keep it together.

Your whole set up doesn't sound like it's a good fit for your truck. What transmission do you have? You may want to put the stock converter back in. Where is your timing set at?

[Fairlane514]

What kind of a torque converter do you have? What stall speed? That can make a big difference in how the  truck responds from a stop.

[westsidek20]

Sorry for the late response, but i will update once i figure it out, thanks for all your comments.
For now i will take it to a pro shop, first thing i will have them check out the tranny (TH400), from then maybe the cam.

You are right Vile, im guessing that the set up was wrong, when im going around 70mph is when i feel the power and it got scary at around 95 mph (imagine the 33's on the K20 with the trampoline bench jumping around) but its not that good from the stop, thats why i might swap the cam.
I was thinking about posting a video of the truck in action, so you guys can see.