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how much power is my 454 making now? and what mods should be next?

14K views 37 replies 10 participants last post by  techinspector1 
#1 ·
I have a 67 c10 with a 82 454 with 1300 miles on the rebuild, I have .525 lift cam, edelbrock performer rpm intake, demon 850 carb, the large oval port heads with stiffer springs and new everything, hedman shorty headers, 2.5" true dual exhaust with flowmaster 40s and I'm curious what kind of power HP and torque I should be making to the crank right now and what I should do next, it is 230hp and 390 ft lbs tq stock.
 
#6 ·
what is the cam duration at 0.050"?

why shorty headers?

I would guess around 360hp and 450ftlbs.

A good build if you have a 3.08 gear. You could use up to 9:1 cr, a cam in the 212-218 degree range at 0.050", and would be better with long tube headers. This would be a 400hp/500ftlb 454.

If you have more gear, like a 3.73 gear, then you could use 9.5:1 cr, and a cam in the 230 degree range. This would make around 450hp.

what is your ignition timing setup? initial, total mechanical, and how much more from the vacuum advance?

BBC's eat cams. be careful not to use too much valve spring and use an oil additive. zddplus.com.
 
#9 ·
what gear ratio?

you can change to a thinner head gasket but that will not help much.

To make a differenece, either change to a smaller combustion chamber head or get some pistons with a small dome. 820's heads have 110cc chambers (10cc less than the 781's).

Or, use the 8:1 cr to your advantage and add some force induction (turbos, super charger, blower, or n02).
 
#10 ·
What is the casting number on your heads? You can pull the heads and angle mill them up to about .100". If you do, be sure you have the intake manifold ends cut as well. Your machine shop must also cut the intake side of the heads.
You might consider the Edelbrock 100cc heads. They are great!!!
 
#11 ·
Here are afew things I'd check if I was you!!! ...IMHO

-Check and see what head you have, GM casting the 049 & 781 are the best (perf. combustion chamber) Then I'd add over size vlv.s, hardened seats, & stiffer vlv. springs. NOTE - 454C10 has it right! "BBC's eat cams." I use a flame hardened cam in my engine.

-850cfm carb is too large for a street driven machine, you'd probably do better with a 700 to 750 cfm carb.

-HOPE who ever built your engine used after the market rod bolts!!! Stock rod bolts are abit "stretchy" with a H.P. motor!
 
#13 ·
454C10 said:
what gear ratio?

you can change to a thinner head gasket but that will not help much.

To make a differenece, either change to a smaller combustion chamber head or get some pistons with a small dome. 820's heads have 110cc chambers (10cc less than the 781's).

Or, use the 8:1 cr to your advantage and add some force induction (turbos, super charger, blower, or n02).
I am planning on running a 100 shot soon and some forced induction later on down the road so I probably will be ok with the low compression
 
#15 ·
11echo said:
Here are afew things I'd check if I was you!!! ...IMHO

-Check and see what head you have, GM casting the 049 & 781 are the best (perf. combustion chamber) Then I'd add over size vlv.s, hardened seats, & stiffer vlv. springs. NOTE - 454C10 has it right! "BBC's eat cams." I use a flame hardened cam in my engine.

-850cfm carb is too large for a street driven machine, you'd probably do better with a 700 to 750 cfm carb.

-HOPE who ever built your engine used after the market rod bolts!!! Stock rod bolts are abit "stretchy" with a H.P. motor!
well I currently have a 650 carb on it in an effort to save some fuel but I bought a Barry grant speed demon 850 for when I'm don't and have a nice set of aluminum heads and a nos setup on it
 
#17 ·
techinspector1 said:
Assuming the intake closes at or around 38 degrees ABDC and using an SCR of 8.5:1, I'm gettin' a DCR of 7.4:1 on the KB calculator. This will not be a particularly strong motor. You cannot just reach out in thin air and pick a cam without doing the math.
Cant be to weak since it runs all over the new 412 hp mustang that weighs less than me
 
#19 ·
techinspector1 said:
Yeah, you're right, your motor must be producing 600 horsepower or better. :rolleyes:
I really enjoy coming on here just to ask a general question and there always has to be one miserable old Dick that answers. Congratulations on making everyone that is a part of this forum look bad. If you want to be a ****** bag then please stay off my post.
 
#21 ·
nfreas313 said:
I really enjoy coming on here just to ask a general question and there always has to be one miserable old Dick that answers. Congratulations on making everyone that is a part of this forum look bad. If you want to be a ****** bag then please stay off my post.
you really shouldnt ask questions, or for any help
if you dont want/like to hear the correct info/answers

he just showed you a chart that supports the help/answers he gave you

and you are arguing with him, telling him he doesnt know what he is talking about

techinspector1 is one of the best guys on this board for building engine setups --on paper/in type on your screen -- so you can see what will work and what wont

he will spend large amounts of time getting info and doing dyno sims for your, and everyone elses' set up

techinspector1 is the man when it comes to helping people, and i dont even fell like you deserve to be on your own post with an attitude like that!

but that is just my opinion
 
#22 ·
I appreciate honest answers but there is no reason to give them with an attitude, plenty of other people answered this without feeling like they needed to talk down to someone. His answers are not what bother me, cans are an easy change, but I find it unnecessary to talk to someone who is just asking for **** and giggles the way he did. I did not come on here claiming to have Jesus under the hood I simply asked peoples opinions on it and I did not clarify that I didn't want people to think that meant to get on here and talk **** because they have something better, this is my first build on my own and I still do not fully understand how exactly to select the perfect cam.. I never attempted to contradict his knowledge of engines, all I am saying is that from now on if you feel like you can't answer the question that I have asked without any ******** comments then please do not bother to reply to my posts. I appreciate constructive criticism but I do not take it well if it is delivered in an inappropriate fashion,

Now, all that being said, does anyone have an idea of what would be the proper cam that I should be looking for, after I open up the heads and run larger valves and with a small nitrous shot?
 
#23 ·
Obviously you don't get it. :(

When a new guy comes on here and tries to bash one of the most respected members, (Believe me - you are not the first)
he can expect difficulties getting interest from anyone else. :boxing:

The response to your comments by TI was pretty much along the lines of what we all were thinking. (Nobody believes that your truck is quicker than a 400HP Mustang :nono: , if you outran one - they simply weren't trying. But to be fair I'll happily :) race your truck with my stock 04 GTO [350hp], on any track within 100 miles of Va Bch)

TI's advice was on the money - you can't pick a cam like your picking your nose :spank: , DO THE MATH! That is the best way to get a good result.

I'll be happy to assist any way I can, but you need to show some respect.
 
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