What I have is a 1977 chevy 400 small block/SM465 tranny and currently it is set up with stock intake and quad carb.

I have a 1990 k5 blazer 4x4 with a 350 TBI/Auto 4speed that develped a knock, (Pulled engine on sat and #1 rod bearing toast). Found a donor Chevy van complete. I plan on pulling the van 350 and putting it into my blazer, which leaves me with a good set of heads/intake (old TBI blazer engine) and all of the TBI stuff off the van, perfect for my v8 swap in my cruiser.

What do I have to do to the 400 for the TBI to work?

I know I need to remove fuel pump from block and get a blockoffplate. Also I know the wiring harness/sensors and new fuel pump need to be used for running reasons....

Main issues are....
Can I use the stock heads, or should I bolt on the 350 heads (for intake issues? (heard that 87 intakes don't bolt up to per 86 heads, correct?)

Any special head gaskets if I go with 350 heads on a 400?, i.e. thickness of the gasket

Camshaft, is the camshaft basically the same or is there a big diff between the older carb/ TBI vehicles, i.e. mainly 350's

Thanks

Not positive on this but from memory, you can use the later manifold (as long as it is not a Vortec)on earlier heads, just elogate the center bolt holes. Early TBI's had hydrualic flat tappet cams, so shoud not be an issue.

Ford pickup trucks (mid 90's I think) had surge tanks that can be used for a reservoir. Also there is a fuel pump, Master PN E2182 that works for TBI applications.

For the funky fuel line fittings these P/Ns have the 3/8" and 5/16" Saginaw fittings on about 18" of hard line to make plumbing the system easier...

Dorman 800-153 and 800-151
HELP or motormite 55187 and 55180

I thought even the vortec manifold would fit on the early heads by rounding out the center hole (is ther another conflict)

your best bet is to just use the heads and intake off the tbi motor

have fun

I might be out to lunch but I thought the Vortec heads had no center intake bolts... Maybe it is just later Vortec heads, but I am most likely wrong...

Anyone else?

The Vortec heads have an eight bolt mounting pattern as opposed to the standard 12 bolt pattern on '86 and earlier heads. Gaskets hould not be an issue as should your choice of cam with the TBI engine. a great source for fuel injection conversion fittings for fuel lines is a company called Godman Performance.

www.godmanhiperf.com
Good luck on the swap!!!!!

Also the computer will have to be modified to run w/ a 400. you might want to give howell a call. let us know what you find cause I would love to turn my 93 TBI350 into a 383 stroker :smokin:

On my particular swap, I am just dealing with the run of the mill TBI from a 350....

From what I found... once you go to MPI/CPI/TPI the intake is diff because of the alum heads, like on the L98/LT1 (Camaro/TA) Don't Quote me ;) older styles should not be too big of problem.

About all I can think of is a inline fuel pump and basically to fab the stock tank with a return and good steel lines, to/from.

Wiring harness should not be too big of problem, everything is in the van, hooked up. Just a matter of eliminating what is not needed. ( too cheap to buy a painless one) :)

On the thirdgen board, basically i found that not to run the 400 gasket, but to use the 350 gasket with the 350 heads. (personally would rather hear from someone who has actually done it) Has anyone used the 350 on a 400 block (should be the same).

I installed a toyota 22re into a suzuki sami and that actuall was not too diff :)

I can help you tune your TBI setup if you want... I have the equipment and software to re-program the EEPROMs based on some some initial educated guessing and real analysis from a program called WinALDL.

I got my TBI setup running just about perfectly on my 2F (it runs a little lean still at highway speeds, which would be easy to correct). You could still use a knock sensor, which would be a great engine-saver if it ever leans way out...

Oh, you'll have to have access to a laptop to plug the diagnostic cable in, and I'd have to know which computer you are using (1227747 is the most popular for tuning software, other versions will cost $25 extra).

Let me know!

Dave

Thanks for the info, I have heard of the WinALDL program when I had my TA, but never got into it. I will send you a PM :D

The computer will more than likely be out of a 2500 vandura (think that is the right spelling) 350 tbi with the auto tranny, stock in van. Will go into the cruiser with the 400/sm465 tranny. I won't know the # on the computer until the weekend.

Hopefully I can keep all the sensors if possible, unless it is better to reprogram the computer and lose some of the sensors.

We actually have a 90 s-10 with the 4.3/tbi that we are going to use for are guinee pig. Basically we are going to try and eliminate all extra wiring except for the basics that make the truck start/run. Should be fun
:beer:

Got lucky and got to strip the van last nite, No puter :crybaby2:

Got all of the sensors and the whole harness and the fuse box. Looks like it will be pretty straight forward swap
into the cruiser....

Anyone know if a computer from a 4cyl or 4.3l chevy is the same as the 350? I know the proms are diff, but I am going to get it reprogramm'd... My buddy has some 4cyl and 4.3 computers, but they are buried in the pile of parts and would rather not go through them unless there might be a donor match

Also on a side note, I assume that when putting a 4.3 TBI intake onto a non-TBI 4.3, you have to elogate the center bolt holes like on the 350?

The computers should be the same. Just the prom is different. You did look for the ECU under the drivers seat didn't you? I just started assenbling my components to put TBI onto my 68 327 in my FJ40. I'm going with the 350 injectors (I've heard 350 injectors are barely adequate for the 350). For your 400 you may want the 350 police injectors as they can put out 15-20% more fuel.

Check out this site. He has lots of info on systems he configures to sell, and also info on how to do it yourself.

http://www.customefis.com/

I am just going to slot the 2 center holes

After reading, you may want to do the 454 Throttle body as it has 2"bores.
I just pulled the harness, sensors, TBI, dist, ECU, EST, out of an 87 Chev truck with Manual trans (no TC lock from the ECU).

just for yourinfo you might allready know

if you use 350 heads on a 400 youwillneed to
drill some vent holes in the heads

ps I recently instaled a pre 1995 manifold
on a 1987 moter I had to elongate the 4
center holes.

"just for yourinfo you might allready know
if you use 350 heads on a 400 youwillneed to
drill some vent holes in the heads"

Not really sure what you mean here, any pics :D



"ps I recently instaled a pre 1995 manifold
on a 1987 moter I had to elongate the 4
center holes."

As in elongate, I guess I am a little lost on that one also, center holes on the head?

Thanks

The 400 heads had extra, small holes (on the head gasket side) that were called steam holes. Because the block has siamese cylinders (no water passage between them) the head had extra holes to help with water circulation. Some 350 heads were used on both 350 and 400 and had the holes. I don't know if the TBI heads had them. I think I would just use the 400 heads.

"slotting the center holes" The TBI intake manifold has the two center bolt holes on each side at a different angle than the earlier manifolds (Look at your 400 and then your TBI) The TBI bolt angles have changed so they are CLOSER to being straight up and down so they wont line up exactly with older heads. Some people use a 3/8"drill, put it into the center holes on the manifold (off the engine!!)and twist the drill to make the holes slotted so the bolts will fit through into the older heads. I am also playing with the idea of making a bushing of some sort to put under the bolt head to take up the different (new) angle. Some people use a dremmel tool to gring the new angle onto the manifold.

There are also some aftermarket manifolds to put TBI on older heads (so i've heard).

I wont be starting my change over for a little while. I'm just collecting all the parts now. Just have to modify the Chev harness to use with my 71 and figure out how tho put the knock sensor onto my 327. Might use the coolant drain hole on right side, or drill and tap a new spot.
David :usa:

I'm working on a 91 TBI 350 now, and it's knock sensor is screwed into the water jacket drain plug on the side of the block!

I guess theres no problem now.

I just bought a set of TBI heads this weekend, so no slotting of manifold needed.

David:usa: