I bought a 89 5.0 TBI with a carb conversion. They added an adaptor plate instead of replacing the Intake. Its looks more like a 1/2 spacer. So can i use this spacer instead up replacing the intake? If so will it run any worse than if i replace it? Thanks in advance.

 

Anyone have any input? I was going to get a new exhaust right after the carb install and then a tune up but should i get an intake instead? I'm getting the 1406 Edelbrock Carb.

 

If it's working now it won't hurt anything, but performance - as long as it's the right adapter for the carb - you mentioned getting an Edelbrock 1406 - what's on it now?

The TBI intake is very restrictive, as is the exhaust, and heads.

You need to think into the future, and decide where you're going with all this. For instance, if a 350 swap is in the cards, then you need to decide on what 350 BEFORE you waste money on an intake now. An older 350 will need a different intake than a newer one (pre-1986 heads vs. post 1986 heads) - they have different angles to the intake bolts. This can be resolved with some creative drilling/reaming of the holes in the intake, but why not get it right the first time. Also, I think you need a different yet intake for a Vortec setup, so if Vortec heads are in the future,

I'd say of the 3 (intake, exhaust, heads), the intake is the least of your concerns for performance, and so I'd stick with the intake I have as long as it all works, and concentrate on other issues like exhaust. Heads I wouldn't bother with unless I was getting heads that will work equally well on a future 350 swap - heads are alot of cash to throw at a 305 knowing a 350 is coming.

Then, worry about intake when you have a definite plan and when all those final pieces come together. Make sense? Intake is $200+, kinda silly to get one now that matches your post 1986 heads if you think by next year you will be swapping in a carbed 350 with pre-1986 heads, or better yet Vortec heads or even a carbed LS1.

 

what's on it now?
a Holly

I'm going to move forward an order the Edelbrock 1406 today and get the exhaust installed next week then tune-up at the same shop. Thanks, and i'll keep you posted.

 

I'm curious why your swapping to an Edelbrock from the Holley. Most folks would prefer a Holley to an Edelbrock. I have an Edelbrock, but it's what came with my motor, I haven't had any issues with it and so I've stuck with it. Anyway, I'm just curious.

There won't be much for tuning required on the Edelbrock - 99 times out of 100 they literally run right out of the box. You can do some tuning with the two screws on the front - might save yourself some labor money by seeing what you can do on your own first. Timing will be more crucial than the carb settings.

 

I'm curious why your swapping to an Edelbrock from the Holley.

The Holley I have is VERY old (and the guy i bought the car off told me to throw the old thing away) and i like the "out of the box" of the Edelbrock has. Next is exhaust then getting the tune up.

Thanks for all the help.

 

OK - just curious. Hope it all goes well!

 

Do you mean that they adapted a 4bbl onto the stock TBI intake? Maybe I'm misundertanding, but if that's the case I've never seen that done and would definitely not recommend it.

 

Yes it is a TBI original intake with a Edelbrock adapter. On the Edelbrock website it says the adapter is made for these types of conditions. Why do you not recommend this? Next question is what should I do to remidy the issue? Thanks

 

Are you sure its a TBI intake underneath? I dont see how you would adapt a 4 bbl carb to a 2 bbl TBI intake. It just doesnt seem possible. Id be willing to bet that its a stock carb intake with an adapter. Can you take some pics?

 

"TBI" adapter plates refer to when you do a TBI conversion from a carbed car...effectively turning a 4bbl carb intake into a 2bbl TBI intake. I've never even heard of it going the other way around.

 

I am trying to find a pic while i'm at work but i'm not having much luck. The area where the Carb goes has 4 holes in the intake.

 

Here are a couple of pics. Thanks


https://www.thirdgen.org/forums/albu...ictureid=15810



https://www.thirdgen.org/forums/albu...ictureid=15811

 

That's not a TBI intake. TBI Intakes have a two-barrel hole, and a 3-bolt spread pattern. This is another carb intake, that has been adapted (badly) to fit a different carb type. I believe that carb pattern matches that of the Rochester 4-barrel carb and intake that I removed from my boat to convert to TBI. It may match other carb types as well, but I don't really know carbs that well. I've always been a fuel-injection guy, personally.

It will 'work' as it is, but it's so mismatched, it won't work very well.

I'd either get a carb that actually fits that intake without an adapter, or replace the intake with one that matches whatever carb you get.

At the very least, is that red insert removable? If so, I'd take that out for sure, since it looks like it would lessen the restriction around the intake bores.

 

i guess i'm confused. is the silver part the intake or the black piece that has "firing order" on it? If the black piece is the intake is the silver an adapter? The firing order listed on the black part is the same as any v8 chevy. How difficuly is it to change an intake? Can a novice do something like that? Thanks

 

The intake is the black thing with the firing order on it.

The silver/red thing is an adapter plate.

Intakes aren't super hard to do, but you do have to pay attention to what you're doing. It requires the removal of the distributor, and everything that bolts onto the intake. There are water jackets that go through the intake, so you have to be careful not to get coolant into the oil.

You also have to pay attention to the gaskets, when you put it all back together. There's one gasket on each of the 4 sides, and you have to make sure they all line up with each other.

Then, you bolt it all back together, put the carb on it, hook up any vacuum lines (including the brake booster!), make sure you put the distributor back in with the proper orientation. Hook up the spark plug wires, start the engine up, and set the timing with a timing light (you can rent them at Autozone, if you don't have one).

Now's a good time to check for any vacuum leaks as well. An unlit propane torch works really well (just run it along the edges of the manifold, and listen for a change in engine speed). In a pinch, a can of carb cleaner will work too, but not as well.

Get a manual, and you can probably do the whole project in an afternoon, taking your time, and making sure you do it all correctly.

I have a friend who is, mechanically, a complete idiot, and knows nothing cars, and he replaced his intake manifold gasket on his Camaro, many years ago.

 

Adapter plate looks to be installed upside down.

 

the intake manifold is a stock rochester spreadbore(two small holes in front&two big holes in back),the adapter plate is upside down for what they were trying to acomplish, and the holley carb is a square bore(four equal size holes).
flip the adapter plate and use new gaskets on both sides, bolt the carb back on and your in business.

 

So what type of engine is this or was it?

I am switching to a Edelbrock 1406 Carb. Will this adaptor be acceptable or should i look at a different one? Thanks everyone

 

Honestly if I was you I would just go with the whole setup. Get the edelbrock carb and get the edelbrock intake that matches up with it. Go to your local autoparts store and they will set you up with part numbers to get you rolling. with the setup you have on there now is just gonna jam you up in the future if you start having problems with performance. Just go with a matching set from eldebrock.

 

I just checked at Summit and the 1406 is a square flange carb just like the holley you have now.
flip the plate so the square side is up , use new gaskets on both sides and bolt the new 1406 on and your ready to go.
If its the original motor somebody put that carb'd manifold on there ,I dont think they used carb's in 88, or maybe it's an older motor.

 

thanks guys. I'm going to move forward with the plate and look at upgrading when there is some snow on the ground. I will be working on this tonight so I'll keep you posted.

 

I'm not sure if this will matter now but here are the shots of the intake with and without the adaptor. Is this now the proper orientaition?

https://www.thirdgen.org/forums/albu...ictureid=15844

https://www.thirdgen.org/forums/albu...ictureid=15845

When i took the adaptor off i noticed gas in the gasket. When I re-oriented the adaptor only 3 of the 4 bolts would tighen up. Does this mean of the threads are striped? Do I have any options or do I have to replace the intake? Thanks.

 

Nope, that's not correct either. If you were to take it and flip it front to back (don't rotate it, just pick it up while standing in front of the car, and flip it over away from you), that should be correct.

If the bolts are just spinning freely, and not tightening, then yes, they're probably stripped. If that's the case, there are other options, like drilling the hole bigger and tapping it, and using a larger bolt; or drilling and installing a "heli-coil".

Even so, I still think you'd be better off getting a new intake that is actually intended for the carb you're going to put on it.