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-   -   454 needs more power (https://67-72chevytrucks.com/vboard/showthread.php?t=484809)

68bigblock 09-17-2011 03:39 PM

454 needs more power
 
Hello, I recently started building a 68 chevy short wide. I just dropped a 454 in it with roller rockers, and an rv cam. The block has been bored 60 over. I have a tb 350 with a b&m shift kit and a 2500 stall. This is my first time to really mess with a motor so I am clueless. The truck has plenty of power but it's slow. Runs 80mph tops. Any info or suggestions would be greatly appreciated on how to make my big block run like a champ. Thanks
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68bigblock 09-17-2011 05:07 PM

Re: 454 needs more power
 
I don't have any idea where to start to gain horse power. A cam? The heads? I have no clue but I'm very interested to learn all I can about how to build a powerful motor
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oldblue1968chevy 09-18-2011 12:01 AM

Re: 454 needs more power
 
What rear gears and more specs on motor? Mod neesd to move this to the engine section..

68bigblock 09-18-2011 07:21 AM

Re: 454 needs more power
 
Im pretty sure it has 410 gears. I've only had the truck about a month. The motor came out of my mud truck. I think it has stock heads. It has roller rockers, and an rv cam, edelbrock 750 carb. The block has been bored 60 over. I just purchased an edelbrock torker intake, summit racing headers, and plugs and wires. I've never worked on a motor, this was my first time to pull a motor and install one. I have a group of friends and we have 6 trucks from 68-72. But none of them will give me any advice on how to hop up my motor. I'm the only one that doesn't come from a mechanical background. My brother had the motor built about 6 years ago and paid someone to do it. Where as I'm different and eager to learn all I can about working on my truck. Thanks for your input. I'm sorry I'm new to the site I just joined yesterday.
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68bigblock 09-18-2011 07:27 AM

BBC help
 
Well I'm a new comer to the web site, and to working on my motor. I have a 454 bored 60 over, roller rockers, and an rv cam. 750 edelbrock carb, and I'm wondering where to start. My 68 c10 has all the potential, but I have no knowldge of how to make it run better. It has plenty of power but it's slow. I would like to know where to start on my journey of building a street rod. Any info would be greatly appreciated! Thank you.
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68_chop_top 09-18-2011 08:17 AM

Re: BBC help
 
What is the condition of the motor; fresh rebuild, old, dont know? What is the condition of the spark plugs? Where is the timing set at? What kind of distributor: HEI or points?

Blue Rat 09-18-2011 09:00 AM

Re: BBC help
 
What are you wanting to do. How much are you willing to change.

68bigblock 09-18-2011 09:33 AM

Re: BBC help
 
The motor was built about 6 years ago for my mud truck. I cleaned it up and painted it, it has new plugs, hei distributer, I just got new summit racing headers. I think we set the timing at a 10. I want to put a different cam in it. But I'm clueless on what size I need. The motor was built to pull. Now I wanna make it run. I have a tb 350 with a b&m shift kit and a 2500 stall behind it. With 4:10 gears in the rear end. It's an awesome burn out set up but it's just slow!!
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tattoed71 09-18-2011 11:26 AM

Re: 454 needs more power
 
machine ur heads or buy some , be sure ur intake, heads and cam match and work well to gether. if it was me i would attack the heads, then go from their,

68bigblock 09-18-2011 03:46 PM

Re: 454 needs more power
 
Ok thank you. That's where I'll start then. I just need someone to point me in the right direction, lol.
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prostreetC-10 09-18-2011 04:52 PM

Re: 454 needs more power
 
Not so fast.......let's first find out what heads you have on there. If they are 781s or 049s, you have the best iron oval heads out there. You really need to provide more info. If I was to simply shoot from the hip, I'd say your timing is way off and killing the power. You can't believe what say going from 8* initial to 18* will do to a 454. You also shouldn't be running an open plane torker intake on a low end power plant. You need a dual plane performer or equiv. RV cam is too general of a term. Give us the cam specs. Do you have an HEI? Where is the vac line hooked on the carb? You also probably are over-carb'd with the 750.

All you need is just the wrong combo of cam, carb, intake and timing to really make a bbc run sluggish.

Oh yeah......SHAME ON YOU FOR BEING NEW AND ASKING QUESTIONS!!!!!! lol
You hang with us and we just might get that lil 454 giving all she's got. I have 3 and they all run hard with little bolt on mods.

One other thought.....do you know for sure it's a 454? Please realize that with that stroke, we help you really get this thing making some torque it's going to eat that lil TH350!!

rusty048 09-18-2011 05:35 PM

Re: 454 needs more power
 
+1 on timing and intake. My worn out 454 truck will do 110+mph, not game to go much faster, bit of play in steering. 750 should be fine, stock carbs are 750. I run 800 and regularly pull 11,000+lb
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68bigblock 09-18-2011 07:04 PM

Re: 454 needs more power
 
I'm really not sure what heads I have, I haven't installed the new intake yet, I work out of town on a biweekly basis. I ordered new headers because my old ones are warped and I have a real bad exhaust leak at the block. The motor as it sets: 454 BBC, stock heads, stock intake. New plugs, old wires, 750 carb, horrible headers. Roller rockers, rv cam. That's the extent of my knowledge about the motor. It was built for a 3/4 ton mud truck. Now I want to turn it into a street rod motor.
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geezer#99 09-18-2011 07:08 PM

Re: 454 needs more power
 
One other thing not mentioned in the bad combo of cam, carb and intake is compression ratio. Lots of 454's where advertised as having 8 to 1 or 9 to 1 compression but where closer to the high sevens. When you yank the heads look to see how far down in the hole the piston's are.

rusty048 09-18-2011 07:22 PM

Re: 454 needs more power
 
My 454 is now 7-7.5comp. Still pulls well. Id redo timing and news leads ect
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68bigblock 09-18-2011 10:27 PM

Re: 454 needs more power
 
Thank you all so much for your input!!! I'm gonna try a cam first then heads where as this is a budget build and I can't find any heads under 800$ so I'm gonna try the easy way. If it's wrong I'll learn from my mistake. Thanks guys.
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prostreetC-10 09-18-2011 11:09 PM

Re: 454 needs more power
 
Quote:

Originally Posted by rusty048;4906041. 750 should be fine, stock carbs are 750. I run 800 and regularly pull 11,000+lb
[size=1
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Just remember a 750 quad and a 750 edlebrock are different creatures. You can get away with it but it's not idea. The quad gets its rating from the huge secondaries. The primaries are quite small and where you stay most of the time.

Be real careful of your cam selection! Go too big and you are pissing against the wind. You comp and valve train won't support anything real big. It doesn't take much to get good power for the '73+ low comp 454s. put a 260-268H comp cam, dual plane intake, 600ish carb, good HEI, 1 5/8th - 1 3/4 headers.......most importantly have your timing and carb correctly set up and she should do just fine. You can run a lot of initial timing in those low comp motors. Don't be afraid to run 18* or a little more for initial and 34-36 all in.

GASoline71 09-19-2011 09:37 AM

Re: 454 needs more power
 
One more vote to ditch the TH350 behind that torque monster. Need to look into a TH400.

That's about where my knowledge of BBC's ends. :lol:

Gary

blazer2007 09-19-2011 10:51 AM

Re: 454 needs more power
 
Quote:

Originally Posted by prostreetC-10 (Post 4905975)
Not so fast.......let's first find out what heads you have on there. If they are 781s or 049s, you have the best iron oval heads out there. You really need to provide more info. If I was to simply shoot from the hip, I'd say your timing is way off and killing the power. You can't believe what say going from 8* initial to 18* will do to a 454. You also shouldn't be running an open plane torker intake on a low end power plant. You need a dual plane performer or equiv. RV cam is too general of a term. Give us the cam specs. Do you have an HEI? Where is the vac line hooked on the carb? You also probably are over-carb'd with the 750.

All you need is just the wrong combo of cam, carb, intake and timing to really make a bbc run sluggish.

Oh yeah......SHAME ON YOU FOR BEING NEW AND ASKING QUESTIONS!!!!!! lol
You hang with us and we just might get that lil 454 giving all she's got. I have 3 and they all run hard with little bolt on mods.

One other thought.....do you know for sure it's a 454? Please realize that with that stroke, we help you really get this thing making some torque it's going to eat that lil TH350!!

just trying to brush up on my timing skills,when you mean intial timing ,that is at idle with no advance. So your talking 8* btdc. and if so isn,t 18* btdc alot?

prostreetC-10 09-19-2011 12:45 PM

Re: 454 needs more power
 
1 Attachment(s)
Yes idle with vac line off and port plugged. 8* initial is 1974-75 gas crunch chiltons/haynes setting for zero performance and ultra fuel savings. You need advance to correctly burn that leaner idle fuel mix. These lower compression 454s LOVE as much initial as you can safely run. The motor below is a slightly warmed up 454 with similar specs as I wrote above. Nothing special and you better wear a diaper when I give you a ride. She flat gets it. I'm somewhere between 18*-20* initial with ZERO pinging/detonation.

When it was in my 6,000 lbs 3/4 ton, it was a stump pulling monster!

GRX 09-19-2011 06:22 PM

Re: BBC help
 
My suggestion would be to search this board (and others) to see what others with similar set up and goals are running - cam, gears, fuel system, etc ...

68bigblock 09-19-2011 07:06 PM

Re: 454 needs more power
 
Yesterday I talked to a friend of mine about a cam and he said he has a comp 305 Hydraulic cam, springs and valves. He said it work great in my truck but all the info I've read it would be way to much of a cam for my motor. So my question is, what does a motor run like if the cam is to big? Just so I'll have a clue. My motor was built to pull. I've up rooted trees, stumps or what ever when it was in my 3/4 ton. Now that it's in my 68 all it does is burn the tires. It has no get up what so ever, or top end. I love the low end but I want it to be faster and get there quick!
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LONGHAIR 09-19-2011 07:27 PM

Re: BBC help
 
Quote:

Originally Posted by 68bigblock (Post 4905286)
It's an awesome burn out set up but it's just slow!!

You have to cure that first, burn-outs are not "fast". You are just spinning the tires and not moving.
What do you have as far as tire size, leaf or coil, LWB or short, etc.

LONGHAIR 09-19-2011 07:34 PM

Re: 454 needs more power
 
Merged, Please don't do this, it is confusing for everyone trying to help....and for you trying to keep the answers straight. It's against the rules for a reason.

Quote:

XIV. Multiple Posting - It is simply not acceptable to post your question more than once, or to post it in more than one forum. Choose the forum that your question or post best fits in, and place it there and only there. If, after posting, you feel it should be in another forum, private message the forum Moderator and ask if they would move it for you.


ItsRandy 09-19-2011 08:36 PM

Re: 454 needs more power
 
Quote:

Originally Posted by prostreetC-10 (Post 4905975)
...SHAME ON YOU FOR BEING NEW AND ASKING QUESTIONS!!!!!! lol


Ricky Bobby...I shake my head every time I see one of your posts. Cracks me up!


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