Budget 454 build

I have no vacuum advance at idle (has a vacuum cutoff for idle, first and second on the MT). Initial advance falls at 11.

I had to modify the idle circuits of my Qjet to get more AFR at idle. Before I modified, it was running too lean...around 14AFR at idle. Idle was crappy....more of a lean roll. My BB likes 12.5AFR at idle. Idle is lopey but consistent at roughly 700+ RPM.
 
Do you have enough vacuum to run the vacuum brakes?

I think I'm, going to try a 830 double pumper from a NASCAR team. It's the only larger carb I have right now

Did you get your engine dyno'd?

I imagine it's probably worth while to get my engine dyno'd and tuned.

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I'm getting about 11" vacuum. Should be enough to run the brakes. My brakes are manual.

Are you putting on headers? Don't you think that 830 might be a little much? Bigger CFM carbs are better at higher RPM's. I am running my 750 and it runs much better than my 800. The secondaries are opening earlier on the 750 which gives me more power at midrange RPM's. If you are going to be off-roading, I would think that you probably want better low/midrange torque..no?

Run your truck and specs through the holley carb selector. It will tell you the size carb you should get.

I had mine dyno tuned. 530 ftlbs tqe at 3400 with 460+HP at around 5400. Had a problem with the stock distributor...it crapped out on the dyno at 5400. Have a DUI on there now and it pulls to 6k....I haven't revved it any higher than that.
 
Yeah maybe it is too big, it probably flows more than 830 also

I think I have another carb, but it's vacuum secondarys and I'm not sure what size. Hopefully it's a 750
 
Not so much anymore :smash:

I was planning on having more money after the build to do some other things, but it looks like those will have to wait a bit

Edit:

Heres my retrofit lifters from crane

2u6d0ye.jpg
 
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Yellow73SB said:
Yeah maybe it is too big, it probably flows more than 830 also

I think I have another carb, but it's vacuum secondarys and I'm not sure what size. Hopefully it's a 750
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A have a 750 Holleythat might be good for what you're doing.... needs a rebuild kit with new gaskets but is clean and complete.... I posted about this carb before:

http://vettemod.com/forum/showthread.php?t=3843&highlight=carb+holley

I found the rebuild kit, it's like $50 (page 2 of that thread)
 
It looks like this was actually originally a 600 cfm

and the vacuum carb is a 750
 
Yep, bottom end is good to go

I should be putting the heads on today and hopefully the valve train

Now I have more of a carb problem :smash:. We rebuilt the 750 and put it on my dads 502 because I told him it would run better and well I was right.

Now I have a 600cfm double pumper and 870 vacuum secondary carb.

I should be able to get $200 out of both though and buy a refurbished 750 from holley.
 
Yellow73SB said:
Yep, bottom end is good to go

I should be putting the heads on today and hopefully the valve train

Now I have more of a carb problem :smash:. We rebuilt the 750 and put it on my dads 502 because I told him it would run better and well I was right.

Now I have a 600cfm double pumper and 870 vacuum secondary carb.

I should be able to get $200 out of both though and buy a refurbished 750 from holley.
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You going to break it in on a stand or in the truck?
 
MYBAD79 said:
Yellow73SB said:
I should be able to get $200 out of both though and buy a refurbished 750 from holley.
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see my post above.... if you want it it's yours, it just needs a rebuild kit....
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Appreciate the offer but is that a square bore pattern?

SmokinBBC said:
Yellow73SB said:
Yep, bottom end is good to go

I should be putting the heads on today and hopefully the valve train

Now I have more of a carb problem :smash:. We rebuilt the 750 and put it on my dads 502 because I told him it would run better and well I was right.

Now I have a 600cfm double pumper and 870 vacuum secondary carb.

I should be able to get $200 out of both though and buy a refurbished 750 from holley.
Click to expand...

You going to break it in on a stand or in the truck?
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I'll break it in on the truck. With the roller cam It won't be much of a hassle.
 
I think I may try the 870, I did the carb recommender thing and it was one on the list

I just looked up all the factory settings and I'll put them back

It ran like shit on my dad's 502, probably because he changed everything and didn't really know what he was doing :crylol:

I don't really have a clue either, so I'll probably be asking for help soon
 
Yellow73SB said:
It ran like shit, probably because he (the previous owner) changed everything and didn't really know what he was doing :crylol:

I don't really have a clue either
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we have something in common :D :clap:

The dry rotted gaskets didn't help either.... it will run fine with new gaskets and correct size jets.....

it's sitting here in a box collecting dust, if you don't want it will go in this years Christmas giveaway thread...
 
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