here's my project with problems and pic's

[MEGALADON]

I have an 82 GMC, the 350 blew up when I got it, so I put a 305 in at the time because thats all I had. I then got a 78 3/4 ton GMC with a 454, well I blew up the 305, then installed the 454. What a big damn difference

Anyways, I put flowtech headers on it and the don't fit worth a damn
it's a hair away from my front driveshaft, and rub's the leaf on the otherside.
These are suppose to be for a 4X4. Oh, and it does rub the front D/S
hard.

So that was problem #1, here's #2

The flywheel was kinda ate up on the 454, so I bought a new one. It had
a 400 trans behind it, but my truck has a 350 trans that I left in it.
When I went to mate up the 454 to the 350 trans the T/C bolt would not even line up, so instead of pulling the motor again, I just grounded the holes out bigger (WISH I NEVER DONE THAT). Is there a special flywheel I need??


So far thats it, If you have read my other threads, you'll see, i'm trying
to figure the best tire and wheel size now. Thanks all.

 

[MEGALADON]

more pic's

 

[Sandman]

The first problem is just the style of headers. I had the same problem and ended up switching to some Chevelle headers to have everything up real high.

kinda hard to see in this pic but well worth the effort to fit them in..

Did you have two sets of holes on the flexplate or just one? They would be offset on each "rib" like thing. The newer ones have 6 holes and each set has a different offset for what style of converter that you have.

 

[MEGALADON]

It had 2 different set of holes, and neither fit the bolt patten for the T/C
I am going to pull the trans and put in a 700R4 that I already have.

I am going to find a suburban front end like yours for my truck to.
Those front ends look bad Ass.

How do I know whats the best header to fit

 

[Sandman]

Maybe search around on here some. I know its been discussed a few times. Maybe you can find a brand name or something.

Yeah, I like those front ends too. I swapped that one in also.

 

[LongIslander26]

Flexplate

You need to know if the motor is internally or externally balanced before you just go slapping any old flexplate on there, or you'll pound the crank bearings to pieces.You need a big block flexplate on a big block motor, if the TC doesn't line up, then you need to swap it for one that does. Also, Flowtechs are just cheap junk. I don't anyone who's had a set that didn't just end up throwing them away inside of 6 months, either for fitment problems like yours, or having to constantly fix leaks. I got Heddmans on both my trucks, and never had problem one with them.

 

[MEGALADON]

You need to know if the motor is internally or externally balanced before you just go slapping any old flexplate on there

First off i'm not STUPID, 2'nd I know what flex plate went on there, it was a new OEM plate for this motor. I'm thinking the T/C is where the problem was.

 

[Sandman]

You need a big block flexplate on a big block motor

Not quite. Only the 400 SB is externally balanced and the 454 BB is externally balanced besides uncommon motors.

 

[seschev3]

more pic's

Not to be off subject, but you might want to put a fan shroud on to help keep that big block cool.

 

[Russell]

Not to be off subject, but you might want to put a fan shroud on to help keep that big block cool.

I'll be off topic too

Do yourself a HUGE favour, and pull that filter off and throw it in the trash. I cannot tell you about how many people have had their rigs go up in flames because of those things, they seriously should be illegal. The problem with them is that the foam absorbs gasoline from the carb, then if your engine ever backfires, you'll have a flaming ball of molten foam. If it doesn't light your whole rig up, it fills your intake, and heads with the melted foam, and makes an enormous mess. Usually melts the carb, and very often starts the fabric on the hood up as well.

Simply not worth the risk as far as I am concerned!

 

[steve_kibbe]

Not to be off subject, but you might want to put a fan shroud on to help keep that big block cool.

I'd lose the flex fan too, either go stock with a clutch or electric

 

[MEGALADON]

I'll be off topic too

Do yourself a HUGE favour, and pull that filter off and throw it in the trash. I cannot tell you about how many people have had their rigs go up in flames because of those things, they seriously should be illegal. The problem with them is that the foam absorbs gasoline from the carb, then if your engine ever backfires, you'll have a flaming ball of molten foam. If it doesn't light your whole rig up, it fills your intake, and heads with the melted foam, and makes an enormous mess. Usually melts the carb, and very often starts the fabric on the hood up as well.

Simply not worth the risk as far as I am concerned!

LOL, yea i know, BEEN THERE DONE THAT , on my 67 impala years ago.
they go up in flames quick. It is temporary, as the throttle bracket wont
let my put on a 14 inch air cleaner I need a 454 throttle bracket.
missplaced the original when it was torn down

 

[Russell]

Why not pick up a spacer? They can be had pretty cheap. Just replace the rod that holds the aircleaner down with a longer peice of allthread, and spend the 10 bucks or whatever it is for a 1 inch air cleaner spacer

 

[MEGALADON]

Why not pick up a spacer? They can be had pretty cheap. Just replace the rod that holds the aircleaner down with a longer peice of allthread, and spend the 10 bucks or whatever it is for a 1 inch air cleaner spacer

I'll take a pic later and show you, its a bubba job right now.
I just wanted to get the truck running and driving to see the difference
of the big block.