Carb conversion for Gen6 454?

[Rede]

I've been trolling around the net for the past month on info for how to convert the Gen6 (96-up) Vortec 7400 to carb for use in my early 80's pickup.

I bought a complete motor for 750 beans that is complete minus accesories and the engine wiring harness (but I do have the PCM).
Basically, the owner swapped out this 454 for a 350 to gain mileage...they gained 3mpg.



Can someone shed some light along with an intake part number so I can physically see the proper intake port design?
I've been told to just get an oval port intake like a performer, torker 2.0 or Airgap 2.0 but if I buy the wrong intake, I can't take it back.


I aslo need to know which flexplate I'll need to bolt this motor to the Turbo400 I plan to run behind it and what to do for accesories...
Can I reuse all my 80's engine accesories from my old motor, or do I need to buy all the 99-ish accessories and go to the serpenine setup?





I found a guy who has a new 502 with factory intake, cam and all the valve train for sale for 500 bucks (which I've been told that the 502 cam is a nice upgrade) but I don't know if its a dirrect swap or not... so I told him I'd try to get some answers before taking the plunge.



Truck will be a winter DD for driving around town/trail/mud toy.
Mileage isn't a large concern as I'm never going very far, but reliablity, winter driveability in the middle of winter are my biggest concerns.


I'm not opposed to going EFI, I'm just trying to keep the build simple and cheap as this truck has been bleeding me dry since I bought it.
I just want to get it running and work out the kinks/bugs before I'm depending on it in the middle of -45C during the winter.

[Rede]

Anyone?

[clinebarger]

Originally Posted by Rede

I've been trolling around the net for the past month on info for how to convert the Gen6 (96-up) Vortec 7400 to carb for use in my early 80's pickup.

I bought a complete motor for 750 beans that is complete minus accesories and the engine wiring harness (but I do have the PCM).
Basically, the owner swapped out this 454 for a 350 to gain mileage...they gained 3mpg.



Can someone shed some light along with an intake part number so I can physically see the proper intake port design?
I've been told to just get an oval port intake like a performer, torker 2.0 or Airgap 2.0 but if I buy the wrong intake, I can't take it back.


I aslo need to know which flexplate I'll need to bolt this motor to the Turbo400 I plan to run behind it and what to do for accesories...
Can I reuse all my 80's engine accesories from my old motor, or do I need to buy all the 99-ish accessories and go to the serpenine setup?





I found a guy who has a new 502 with factory intake, cam and all the valve train for sale for 500 bucks (which I've been told that the 502 cam is a nice upgrade) but I don't know if its a dirrect swap or not... so I told him I'd try to get some answers before taking the plunge.



Truck will be a winter DD for driving around town/trail/mud toy.
Mileage isn't a large concern as I'm never going very far, but reliablity, winter driveability in the middle of winter are my biggest concerns.


I'm not opposed to going EFI, I'm just trying to keep the build simple and cheap as this truck has been bleeding me dry since I bought it.
I just want to get it running and work out the kinks/bugs before I'm depending on it in the middle of -45C during the winter.

The app. guide says this will fit http://www.summitracing.com/parts/ED...ry=Year%7c1996.

You dont need to change the flexplate.

Not 100% sure on the front accessories. But i think they will.

[Rede]

Unfortunatly there was no flexplate included at all so Ill need to know which one I'll need...

The guy with the 502 valve train, cam and intake is selling his parts for pretty much the same price as that intake from summit by the time I get nailed with tax/duty/shipping/brokerage so I'm tempted to take the works but only if it's swappable.

[bwood]

I believe you can just look up a flexplate for the year/vehicle the 454 came out of and it should work.

[Rede]

Okay thanks.
I didn't want to buy the wrong one just incase.

Does anyone know if the 502 valve train, cam and intake are dirrect swaps?

[Rede]

Here's the info I was able to dig up on the 502 valve train but its all greek to me...

Camshaft duration (@.050 in):
224 degree intake / 234 degree exhaust
Camshaft lift (in):
.527 intake / .544 exhaust
Camshaft Part Number:
12366543
Camshaft type:
Hydraulic roller


Rocker arm ratio:
1.7:1
Rocker arms Part Number:
12368082
Rocker arms Type:
Stamped steel

[chubb]

Originally Posted by Rede

Unfortunatly there was no flexplate included at all so Ill need to know which one I'll need...

The guy with the 502 valve train, cam and intake is selling his parts for pretty much the same price as that intake from summit by the time I get nailed with tax/duty/shipping/brokerage so I'm tempted to take the works but only if it's swappable.

You can only use a flex plate for a 454 an none other...an as far as the intake goes I have a 98 454 with a factory 1967 cast iron holley intake on mine...so the air gap edelbrock would be fine...don't forget the distributor you use with it you will have to change the gear on it for the roller cam that in your 454...good luck

[Rede]

It ran well for the moving around in the yard, but on the way across town from my friends house to mine, a hose on the oil cooler split (rubber line to go from the oil cooler's hard lines to the aftermarket cooler's fittings) and puked out all but a few litters...if that.

Truck died literally across from my driveway and the engine is seized solid :cry:

Started getting ready to pull it earlier today and hope to have it out tomorrow night if all goes well.

I bought a 6.0L LQ4 with the carb intake and MSD box to go in the 7.4L's place.
Downside is that ill be down about 50hp and just over 100lbs of toque by switching to the 6L...
Posted via Mobile Device

[finch]

if there are any local engine machine shops in your area it may be best to give them a call and ask about the compatibility of the 454/502 valvetrain stuff.

[Rede]

There really isn't anything here besides you're usual repair shops.
There is a wannabe performance shop, but the owner is the only guy with half a clue and he's more of an old school guy... the joys of living in a smaller comunity! >_>

[Rede]

Just an update for anyone else stumbling on this:

I picked up a Performer 2.0 intake (oval port) that I was told should work.

It's not running yet as I'm doing a few other things (cam and valve train upgrade along with front and rear diffs swapped) but I've been told that it is deffinately doable.

[turp mcspray]

You MUST use a gen V/VI flexplate, or you will have an imbalance problem. They have a different sized weight than the mark IV engines. They also use a different one for forged and cast cranks. The weight looks different as well. I would just get one from your GM dealer. All of you accessories will bolt on the same. I have a gen VI in my 87 one ton and learned of all the differences when tracking down a vibration. (previous owner used the old mark IV flexplate)

[Rede]

I was just asked what the engine was and what trany I was using. (80's th400) Then he asked if it was a one or two piece rear main seal.

How do I ensure I have the proper one?
I just have the oem replacement so it's not a brand name and I don't think there's any parts number to check...
Posted via Mobile Device

[454HO]

I am running a '99 Gen VI vortec converted to carb in my truck. I'm using a standard Performer 2-O intake manifold, part number 2161. The ports on this manifold are actually smaller than the ports on the vortec heads. I wish I had bought the Performer RPM manifold, but I really doubt it would make a huge difference in performance.

The ZZ502 camshaft WILL NOT WORK with stock Gen VI vortec heads. The issue is too much valve lift... the valve spring retainer will bottom out on the valve guide. You may be able to use beehive valve springs and matching retainers to gain enough clearance. Or more likely, you will need to pull the heads and have the valve guides machined.

A possible alternative would be the Mercruiser M1 cam. It has the same .483" lift as the stock Gen VI vortec cam, but it has 225 degrees duration at .050". This is the cam I am running in my engine. See my thread on Team Chevelle for more details.

http://www.chevelles.com/forums/showthread.php?t=264788

[Rede]

Originally Posted by 454HO

I am running a '99 Gen VI vortec converted to carb in my truck. I'm using a standard Performer 2-O intake manifold, part number 2161. The ports on this manifold are actually smaller than the ports on the vortec heads. I wish I had bought the Performer RPM manifold, but I really doubt it would make a huge difference in performance.

The ZZ502 camshaft WILL NOT WORK with stock Gen VI vortec heads. The issue is too much valve lift... the valve spring retainer will bottom out on the valve guide. You may be able to use beehive valve springs and matching retainers to gain enough clearance. Or more likely, you will need to pull the heads and have the valve guides machined.

A possible alternative would be the Mercruiser M1 cam. It has the same .483" lift as the stock Gen VI vortec cam, but it has 225 degrees duration at .050". This is the cam I am running in my engine. See my thread on Team Chevelle for more details.

http://www.chevelles.com/forums/showthread.php?t=264788

I just installed an M1 cam thursday night, but I have a bunch of other stuff to do before I can test it out.
I have the part number of everything from competition products for your valve train upgrade too if you ever want to take advantage of the full cam
If you use a dremmel on the inside of the rotor eliminators, you won't have to do anything to your valve guides and no need to pull the heads (wish I thought of that sooner)
Just test fit, take a little off and re-test. Rinse and repeat untill it falls into place.
The rest was straight forward like any other LS based motor pretty much...
Posted via Mobile Device

[454HO]

Originally Posted by Rede

I just installed an M1 cam thursday night

Cool. The M1 is not what I would call a performance cam, but it is definately a big improvement over the stock cam.

Originally Posted by Rede

I have the part number of everything from competition products for your valve train upgrade too if you ever want to take advantage of the full cam

Yes, I need to upgrade my valve springs. I am still using the originals. Would be interested in seeing your parts list.

[turp mcspray]

Originally Posted by Rede

I was just asked what the engine was and what trany I was using. (80's th400) Then he asked if it was a one or two piece rear main seal.

How do I ensure I have the proper one?
I just have the oem replacement so it's not a brand name and I don't think there's any parts number to check...
Posted via Mobile Device

Just make sure it is for a one piece rear seal. 91 and up. If you compare a mark IV flexplate to a genV/VI, the newer one will have a taller weight, which is very obvious.

[mongoose]

nothing a turbo can't fix.

[suxtobu65]

Old thread recover... Got a question.. $35 BBC roller camshaft.. Are these still available and if so where??? Ive searched ebay and Comp Products and cant find them.. I've been looking for a stock Vortec 454 cam for months now!

Merc Mag Roller
Merc# 431-850478 / GM#12551622
.004 300*/ 300*
.006 288*/288*
.050” 225*/225*
.200” 125*/125*
Lift .483”/. 483”
ICL 109*
LSA 115.5*
M1


Anyone have any clue where to get one of these?? I'm in dire need of one!!!

[Sourdough]

I did this swap in an 84 gmc 3x3. I used most of the info in this very thread to achieve the swap; 96 vortec 454, long duration cam, marine electric fuel pump, low rise intake off a 70's bb, etc, etc....

I know it's an old thread, but figured I'd let everyone here know that this swap is not only plausible, but mine is out in the driveway warming up this morning for the trip to work.

['63GENIII]

Hey Sourdough, how do you like the performance of that 454? I have an injected one in the garage that is going to end up in the '63. There is not a lot of performance information out there for these engines. I read up anytime I find anything on the L29's

[Sourdough]

It's a good engine. Roller rockers. Plenty of torque, and you can run them up to about five grand and be safe doing so. The only downfall with them is you have to do some head work on them if you want to put a bigger cam in them. The valve springs have to be modified. Mine snorted pretty good with the m1 cam. It was plenty for me.

Unfortunately, I blew the valve train on mine last week.....bummer deal, but you play you pay. Haha.

I bought a truck with a tonawanda gen five in it. The old 84 will have a new heartbeat again soon

I recommend the gen six roller engines. They're pretty tough, and you can get 12-14 mpg with them. I actually owned the donor truck mine came out of, and you can't beat em.

[Sourdough]

I like the gen 6 rollers. They seem to last, get better mileage, and have torque all the way through the power band. I've abused mine, and I finally wound it too tight and did some valve train damage. I found another one from a fleet liquidation with 55k miles on it. Gonna gear it up just like the other, and sink it in the same truck. They're good engines.

[mechanicalman]

Originally Posted by Rede

I found a guy who has a new 502 with factory intake, cam and all the valve train for sale for 500 bucks (which I've been told that the 502 cam is a nice upgrade) but I don't know if its a dirrect swap or not... so I told him I'd try to get some answers before taking the plunge.

That's an OK deal, even better if the heads are included. If not, I'd look for some oval port heads with smaller combustion chambers.

I'd swap out the heads, bigger ports, and more cam/valve lift potential.