Bsxpress

Hi everyone,
I have a lead.....well better than a lead... on a set of 80-81 OEM tube ramhorn headers.
I was “on the line” checking on what people are asking for them and I found set of OEM tube center dump manifolds from a C4 for cheap and was curious which ones were better.
The car is a 76. The motor is a 95-99 non-Vortec tbi that I’m carb swapping. It has non cated true duel exhaust.
Any information will be appreciated.
Brian S.

Kacyc3

tbi = 86-95, you will be disappointed with this engine in a sports car.
vortec = 96-01, chances are this engine doesnt have the hole for the fuel pump rod drilled and possibly no lobe on the cam to actuate it..

Which engine do you have?
Most people chose center dump ram horns from the 60s- mid 70s when choosing to use manifolds.

7T1vette

If I am not mistaken, the LT-1 engines of 1970 used the same exhaust manifolds as the L-48 engine. That tells me the exhaust manifold was not the 'weak link' in making "decent" power.

Also, bigger is not always 'better' when it comes to outlet manifolds. Some amount of back-pressure is beneficial.

cv67

The 92-96 LT-1 manifolds are better than the TPI pieces (if that answers the question)they are cheap enough
The 80s tubular pieces were pretty restrictive (motors suck also)

Bsxpress

My motor does have the hole and cam lobe for the fuel pump. So I’m good there. As far as “ it’s not a good motor for a sports car”. Well, it’s better than the POS L48 that’s in it now. And the price was right.
Im not trying to make it go faster so much as I am trying to make it more reliable.
And I want to drive this car as much as I can so I want mileage. At least the best I can get without going fuel injection. I have an o/d transmission that I am going to put in as soon as I can get the rear gears (3.55 ish).
I’m going to put the tubular ramhorns on it and go.
Either way I’ll be glad to get rid of the long tube headers on it now. They need replacing anyway and I don’t like the heat they put off. And all the pinholes..... I could go on but I’ll spare you that rant.

So I just got home from doing a little work on the motor and after removing the oil pan I discovered 2 things:
1 it DEFINITELY has the lobe for the fuel pump and
2 it’s a 2 bolt main.
It is so clean inside that I really wish I knew how many miles are on it.
Not many by the looks.
I know about the intake and will have one here an about two weeks.
And as I have stated above. I’m more about going the distance than going gas station to gas station.
My plane is to run this engine until I can afford to rebuild the original motor that I’m removing.
I just cant afford to do it “right” all at once and I want to drive the car not look at it.


And just so all of you guys that have responded ti this
thanks I really do appreciate all the information and I would respond individually but having a hard time figuring out how without filling it up with “quotes “ lol.

Bsxpress

Oh and the only info I could find just lists 95-99 TBI.
It’s got 880 in many different places on the block and is the last 3 digits in the engine number. Iv read that this is the same block that gm uses for the zz creat motors along with a factory 383 stroker (I, personally have not heard of this from the factory).
Anyway..... ;-)

jackson

OP
does your 880 block have a roller cam in it now?

Bikespace

80 had cast manifolds. I have a set I can give you for the cost of shipping. 81 may have had shorty tube headers. All are likely to have AIR tubes obstructing the exhaust flow.

I think most had 2" outlets. If you want cast manifolds, look for the ones with 2.5" outlets. Lots of repros available at Jegs, Summit, etc.

Kacyc3

1 Thats good.
2 I wouldnt bet on it, my 87 tbi truck was flat after 3k rpm, it revved but didnt pull. 3 the intake manifold uses different angle bolt holes in the center you may have to get a different intake or drill new holes. Those tbi engies were engineered for low rpm torque and mileage. it will need new heads and cam if you want to upgrade it.
3 Far as I have found these are the best flowing manifolds in stock form.
4 I just read a post where a user bought stainless steel long tube for dirt cheap on ebay, you could also wrap the stainless with header wrap to remove the under hood temp.. I have to do the same.

carriljc

If your car has been modified to true earlier C3 exhaust (through the center crossmember) then I would suggest the 2.5" ramhorns (various different options available) with the 1964 2.5" downpipes, then the rest of the regular 2.5" exhaust system of a C3.... that way you'll have 2.5" all the way to the outlet of the stock mufflers (they're 2" as I discovered on mine). Here are some stories and mine:
https://www.corvetteforum.com/forums...c3-79-a-2.html

OldCarBum

If you want a good quality cast manifold, check out these from Sanderson Headers.
They also produce the highest quality tubular short tube and mid length headers I've seen on the market.

Bsxpress

no it does not.

Bsxpress

So I just got home from doing a little work on the motor and after removing the oil pan I discovered 2 things:
1 it DEFINITELY has the lobe for the fuel pump and
2 it’s a 2 bolt main.
It is so clean inside that I really wish I knew how many miles are on it.
Not many by the looks.
I know about the intake and will have one here an about two weeks.
And as I have stated above. I’m more about going the distance than going gas station to gas station.
My plane is to run this engine until I can afford to rebuild the original motor that I’m removing.
I just cant afford to do it “right” all at once and I want to drive the car not look at it. (After reading this over it sounded kinda harsh. NOT at all how it was intended)


And to all of you guys that have responded to this
thanks I really do appreciate all the information and I would respond individually but having a hard time figuring out how without filling it up with “quotes “ lol.

derekderek

No roller cam. Post pics of lifter valley. That MAY be ready to install a roller cam. The dog bones, spider and OEM lifters are cheap. What casting number on the heads? The TBI heads are crap. You would have a hard time finding worse ones. Valve seals and lap the seats in your orig heads will be an improvement. Not much of one though...

Bsxpress

I’m not going to do a roller cam at this time. Maybe later on.
The heads on the engine in the car now have MUCH larger valves. I changed my head gaskets not that long ago(they were bad but it didn’t fix the issue hence this motor swap) and the valves looked like they might be 202/194s. Which makes me also think they are not original to the motor.
When I have more money in the budget I’ll have them gone over and probably use them. Orrrrrr I’ll pick up some Vortec heads.

Kacyc3

look for casting numbers on the heads, if they end in anything other than 191 or 193 they have been replaced. Vortec heads may require you to fab/modify,swap your accessories due to being mounted using intake manifold bolts.

Bsxpress

It has the 193 numbers. I believe what I’ve read is that these are the less desirable of the two do to them being from a truck.
I’m ok with that. I like the thought of mileage over high revs anyway.

Kacyc3

Ever drive a tbi fbody... They're what you're in for except they had better cams than the truck engines.

Bsxpress

I have not driven an fbody tbi. But
I am very much looking forward to this swap.
I’ve put about 60 miles or so on the car sense Friday and the old motor just sounds like it wants to come apart.
Not really, but the spark knock and gutlessness upon pressing the gas pedal is awful. And it runs around 200° +\- so im not sure if it has a thermostat in it.
I’m not going to find out until I swap the motors.
I need the housing(and yes I’m putting a new thermostat in regardless) for the new motor.
I still have to get the correct intake for the carb swap and all the key major parts are taken care of.
Once i have all that done I will pull the old motor, swap the accessories over and drop the new one in.