Double wall exhaust system, anybody do it ?

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Grit dog

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A carport for shade would be a huge improvement, but as things stand now, on my low fixed income, I am lucky just to keep the house/land/trucks going and have food and other basic necessities.
Any construction projects would be a luxury not in the budget, so i deal with working in the elements.

****, sorry dude. Wish I was closer. I could fix ya up with all kinds of materials. Been trying to give a way a few squares of shingles for a year now...
There's always redneck air conditioning (wet shirt and doo rag).
 

Bextreme04

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That thing still workin Kev?
I’d kill for a mechanical fuel pump....
Anyone want to trade a nice peeenut port Vortec 454 for a mark IV??
Anyone?











Hello??

If yours is truly a Gen VI Vortec 454 without the fuel pump boss... it doesn't have peanut port heads. They are actually great flowing oval ports. The Peanut ports are only on the the TBI 454's. The Vortec's have a "ski jump" in the intake, but there are quite a few flow tests out there that show they flow just as good as the 041's up to about 5000 rpm, which is perfect for the truck motors.
 

Bextreme04

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I have several spare pump rods, I will build up some weld on the end of one, polish it smooth, and see if that works.
It did pump adequate gas when it was installed before with the ticking, so I would think the base circle portion of the cam lobe could be worn down, but the eccentric part to operate the rod was still enough stroke to pump fuel.

I also read a thread where someone was having the exact same issue. It turned out their fuel pump had a shorter shaft than others for some reason. They were able to put a thinner mounting plate on it, which took the slack out and got rid of the ticking while still pumping. I still don't think you have a worn cam lobe because it pumps. If it was a worn lobe, you wouldn't have any pumping action and you still shouldn't have any ticking as it would wear the lobe off, not a groove all the way around the cam.
 

Grit dog

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If yours is truly a Gen VI Vortec 454 without the fuel pump boss... it doesn't have peanut port heads. They are actually great flowing oval ports. The Peanut ports are only on the the TBI 454's. The Vortec's have a "ski jump" in the intake, but there are quite a few flow tests out there that show they flow just as good as the 041's up to about 5000 rpm, which is perfect for the truck motors.

sorry for the thread jack Kev....
I believe it’s a Vortec motor based on the 6 bolt timing cover.
Haven’t had a valve cover off though. No leak means no touch!
If that’s the case, good to know. Makes me feel better about it.
I thought both models were small port heads.
So in the last 2 days I’ve definitively determined it’s a GMC and it has a better motor!
This is like the Geico commercial... now if only my high school hair do would grow back!
 

Catbox

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That thing still workin Kev?
I’d kill for a mechanical fuel pump....
Anyone want to trade a nice peeenut port Vortec 454 for a mark IV??
Anyone?

Ohhhh man.
My kid has been trying to get me to put my whole L-29 Vortec 454 into my truck instead of the Mark IV that is in it now...
 

Bextreme04

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Ohhhh man.
My kid has been trying to get me to put my whole L-29 Vortec 454 into my truck instead of the Mark IV that is in it now...

DO IT!!! Then we can have three in the PNW! There's another guy up in the seattle area that has one with a carb on it in his Burb... With just the cam and fueling upgrades I'm hoping for around 400hp and 5-600 lb-ft of torque... It's higher compression than the TBI motors too because the chambers are 99cc in the vortec heads. I recommend sending the cam up to Delta camshaft in Tacoma.. they can regrind the roller cam for whatever you want. I got a towing and torque cam grind on a 114LSA and about .520 lift. The factory roller cam retards the timing by 7 degrees and is not great. New cam is considered the single biggest improvement for the Gen VI. Only cost me $140 shipped and took them about a week.
 

Catbox

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I have a another set of the Vortec heads that I was going to install onto the Mark IV in the truck.
I was going to put the L-29 454 into my '54 Bel Air.
But he keeps pushing me to put the whole thing into the truck.
I told him maybe, but he would have to find and pull another 454 Vortec when the time comes for my car to get one....

For the cam I was going to do the simple ZZ-502 cam as it sounds like a winner to me.
xc_hide_links_from_guests_guests_error_hide_media
 

mtnmankev

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Okay kids, here's the official update-
It was 94 degrees today, and I had to make the 120+ mile round trip to the big city.
Not a single hiccup, never tried to vapor lock even once.
I did notice the driver's side tank needs attention in the vent department, it has pressure when the gas cap is loosened, but it never once affected the engine getting fuel.
 

Bextreme04

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Ohhhh man.
My kid has been trying to get me to put my whole L-29 Vortec 454 into my truck instead of the Mark IV that is in it now...[/Q
Okay kids, here's the official update-
It was 94 degrees today, and I had to make the 120+ mile round trip to the big city.
Not a single hiccup, never tried to vapor lock even once.
I did notice the driver's side tank needs attention in the vent department, it has pressure when the gas cap is loosened, but it never once affected the engine getting fuel.

Nice! you considering the big city Prescott? I haven't been back in a while, hopefully I can get back for the october career fair at Embry-riddle once this corona panic is over
 

volcanomike

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Okay kids, here's the official update-
It was 94 degrees today, and I had to make the 120+ mile round trip to the big city.
Not a single hiccup, never tried to vapor lock even once.
I did notice the driver's side tank needs attention in the vent department, it has pressure when the gas cap is loosened, but it never once affected the engine getting fuel.
If it is positive pressure that is ok, negative pressure is bad.


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mtnmankev

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Nice! you considering the big city Prescott? I haven't been back in a while, hopefully I can get back for the october career fair at Embry-riddle once this corona panic is over

Yes, Prescott.
When I first moved there in 1983, Prescott was an old indian word that meant "You gotta go to Phoenix, because we ain't got it here"
26 years later, the growth and a few other issues told me it was time to move out, so now it's a 60 mile drive each way to get there to shop.
 

mtnmankev

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If it is positive pressure that is ok, negative pressure is bad.


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Definitely positive pressure.
I know if it had a vacuum the fuel pump would have trouble.
 

Bextreme04

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I have a another set of the Vortec heads that I was going to install onto the Mark IV in the truck.
I was going to put the L-29 454 into my '54 Bel Air.
But he keeps pushing me to put the whole thing into the truck.
I told him maybe, but he would have to find and pull another 454 Vortec when the time comes for my car to get one....

For the cam I was going to do the simple ZZ-502 cam as it sounds like a winner to me.
xc_hide_links_from_guests_guests_error_hide_media

Yup, the zz502 cam is a great way to go if you are going to run it in the car... It is as big as you can go on the stock L29 heads before you start hitting stuff. You also need the zz502 springs to match. I'd stick with the original noin-adjustable valvetrain and rockers too. The roller rockers tend to be too heavy and make a lot of racket with the stock roller lifters. I went with the 454HO dual springs, custom cam grind, and left everything else factory. The heads have had new guides installed, positive viton valve seals, and a complete refresh. I'd be super happy if it sounds like that chevelle in the video. Most likely it will be a bit smoother and milder sounding with the MPFI though.
 

Bextreme04

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Yes, Prescott.
When I first moved there in 1983, Prescott was an old indian word that meant "You gotta go to Phoenix, because we ain't got it here"
26 years later, the growth and a few other issues told me it was time to move out, so now it's a 60 mile drive each way to get there to shop.

yeah, that's pretty hard core.... i might have considered outside Chino or something as far enough away myself, lol. All the snowbirds have really taken over. It's a nightmare getting anywhere around there with all of them going 35mph in the fast lane everywhere. And of course all the retired snowbirds really have driven up the cost of living there. You can go down to phoenix and get anything for about 20% less
 

volcanomike

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Definitely positive pressure.
I know if it had a vacuum the fuel pump would have trouble.
Good to hear everything is working. My Camaro always has positive pressure on a hot day. The K10 doesn’t but it has vented tanks and a charcoal canister.


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