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HOT AIR BALLOON OWNER
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Discussion Starter #1
Hello all, yes I need some info! lol What can you tell me about the Vortec 454?

Injectors upgradable? Cams? Gimme the lowdown on what's around for this... 290cc AFR's bolt up? :secret: If them AFRs won't work, how's the quality of the stock heads... like what's their potential if ported?

Thanks! :shake:
 

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03 Tahoe
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1,364 Posts
Yes, you can change the injectors. The marine injectors are the most common upgrade. The 454's are MPFI, not like the CPI 305's and 350's, so there are upgrades. I'm going to ditch my secondary whipple computer w/ the 2 extra injectors, upgrade the stockers to the marine units and then have the stock computer tuned to handle everything.

As far as a cam....I'm not sure if any are out specifically for them but they can be made....

I don not believe there are any aftermarket big block vortec heads out. AFR units could work....edelbrocks could work...it would depend on the intake bolt locations really. I've never looked so I'm not sure if they would match. I have heard than a good port and polish helps a good bit.

Cameron
 

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HOT AIR BALLOON OWNER
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14,932 Posts
Discussion Starter #3
Physh1 said:
Yes, you can change the injectors. The marine injectors are the most common upgrade. The 454's are MPFI, not like the CPI 305's and 350's, so there are upgrades. I'm going to ditch my secondary whipple computer w/ the 2 extra injectors, upgrade the stockers to the marine units and then have the stock computer tuned to handle everything.

As far as a cam....I'm not sure if any are out specifically for them but they can be made....

I don not believe there are any aftermarket big block vortec heads out. AFR units could work....edelbrocks could work...it would depend on the intake bolt locations really. I've never looked so I'm not sure if they would match. I have heard than a good port and polish helps a good bit.

Cameron


I'd assume stock injectors are around 24lbs/hr do you know what they are? How large are the Marine 454 ones? It appeared the ratings were 290/410 stock. Do you know if these suffered from TqMgt also?

Yeah I figure the stock cam is pretty weenie, looks like it falls off around 4300rpm or so. lol Is this a roller cam?

I saw some pics of the intake manifold and it appears it's two pieces so it could be ported potentially. Here's what the ports look like also.

454intakeports.gif


Stock head -
454heads.gif


AFR -
AFR290s.gif
 

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HOT AIR BALLOON OWNER
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14,932 Posts
Discussion Starter #4
Looking close it doesn't appear those AFR's will work. Damn the luck. These Edelbrocks do tho'...

Edelbrock2.gif


Edelbrock1.gif
 

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03 Tahoe
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1,364 Posts
I an 99% certain it's a roller cam. From what I can tell, there is zero torque management. I believe GM started using this on the NBS trucks. Sure, the stock cam falls off early....motor is made for torque...not massive revving.

The intake is a 2 piece, cast aluminum assembly. The upper plenum can be removed to access the stock injectors. Both can be ported but w/o head work or new heads it would probably be useless. You may be right about the edelbrocks...they look like they would fit :think:.

Cameron
 

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HOT AIR BALLOON OWNER
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14,932 Posts
Discussion Starter #6
I've never owned a BBC before so I wasn't sure what to expect with the powerband, my bud used to have a '72 Fleetwood with a 472! It'd do monster burnouts down the street but we had no idea where it shifted at WOT as it had no tach. But this is a tow-truck/tq animal as ya stated.

I'd assume a cam will add mad HP up top and maybe even a broader range of TQ too. I too think it'd be a roller cam.

If those 'Brock's wont work, do you think it'd be worth the time/money to work up a set of the Vortec iron heads?
 

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03 Tahoe
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1,364 Posts
Well, remember than when you get a cam for HP, it's usually for higher RPM and you'll sacrifice lower RPM torque. IMO, if your gonna drop a cam in it, do the intake and head work. When I get my truck back from the shop, I'll likely add a different cam..something a little more favorable to my whipple, do some head and intake work...should be a nice increase. It would be worth it IMO to work the heads.....if you cam it you really need to make sure the intake and heads can flow better to really benifit from the cam.

Cameron
 

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HOT AIR BALLOON OWNER
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Discussion Starter #8
I'd like to see this 454 making power to about 5200rpm and shifting around 5500. I don't think it'd need to pull to 6K for any reason. What are the stock WOT shift points?

I bet you could get some good power from those iron heads but if those aluminum's will work, I'd prefer those.

We'll see what progresses and go from there. lol
 
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