Stunt_Man

Hello to everybody. I have Firebird with dead 305 TBI. I have access to 403 oldsmobile from 2 gen trans am. My th700 will be ok with that 403?

Apeiron

It won't bolt up, the bellhousing bolt patterns are different.

Tuned Performance

iTrader: (92)

BOP

Stunt_Man

i can buy that 403 with th400. that combo will work in thirdgen? what about drive shaft?

Tuned Performance

iTrader: (92)

http://www.hawksthirdgenparts.com/pr...haft-Loop.html
The th400 uses a 32 spline yoke. I think you should put your money into a 350 sbc not somme bastard amc setup.

Apeiron

It will work if you're willing and capable of putting in the effort needed to adapt a non-factory engine to the platform.

Stunt_Man

Transmission and torque arm mount isn't a problem. I'm worried about drive shaft length. th400 isn't shorter than th700?

Tuned Performance

iTrader: (92)

sofakingdom

iTrader: (1)

The drive shaft is a piece of cake. Least of your worries. Measure, call drive shaft shop, pick up on way home from work. Done.

Same for the trans bolt pattern; all that takes, is an adapter plate.

Frankly, for how weak that TA 6.6 usually is in stock trim, I wouldn't bother with swapping in the 400. Not necessary.

The fact that you started your "worries" there, shows that you really don't know what you're getting into.

The fact you're wanting to transplant a transmission but aren't concerned about the torque arm is a big red flag reinforcing the above observation.

The fact you haven't asked about exhaust yet is even more of one.

Don't disable your daily driver to do this swap. You'll be riding the bus for MONTHS at the rate you're going so far.

Stunt_Man

sofakingdom, i'm not worry about disabled my car. now we have a lot of snow and i don't use my f-body so if i have trans bolt pattern adapter i can do this swap with th700? exhaust? it's can be a problem? i know for sure it isn't plug and play but i can do new exhaust. I should worry about space? or what?

thanks to all for your replies!
sorry but i'm not from USA. my english isn't very good

ibmtech

iTrader: (1)

What Sofakingdom is trying to say is that your wasting your time putting a 403 that will take more time of adapting the transmission and exhaust to that engine and you could just put a good 350 or 400 in it. Even if you were given what I presume is a used engine for free, It is going to cost you alot more in money and time than getting a used small block chevy.

Stunt_Man

OK! so i will swap to 350

sofakingdom

iTrader: (1)

Well, that means it will be MUCH harder to get that 403 to work... you probably don't have junkyards full of cars to pick from.

Problem with exhaust is, the stock manifolds on the 403 will almost certainly have their outlets pointed at some feature of the chassis that will make it totally impossible to fit a pipe to it. The 2nd gen and 3rd gen chassis is quite a bit different in that general area. If there were any aftermarket "swap" headers, you could possibly go that route; but I don't know of any.

A Chevrolet 350 would be the best way to go.

ex-x-fire

Google "350 olds in 3rd gen camaro".

diablizzard

iTrader: (8)

I've put a 307 olds into an 85 trans am before. I didn't complete it though, it was for a buddy who joined the army right before I could complete it. It was from an 85 G-body. I used trans dapt adapter to the 700R4, and the G-body frame mounts. Because both motors were set up with the quadrajet I could just move the wiring around and plug it all in. The exhaust was the only main issue when I did it. I forgot what it turned into and hit, I think it was the fire wall on the Passenger side.

Ingram78

403 olds is a turd!

ex-x-fire

A cheap way to add alot of compression to a 403 is to swap on earlier olds 350 heads, worth about 2 points in compression. Keep the q-jet carb, add a modern cam, & headers. For even more you can add the 403 valves to the 350 heads.

sofakingdom

iTrader: (1)

Compression doesn't make too much difference when you can't install the motor.

ex-x-fire

This guy got one installed, looks like headers fit. Most likely block hugger type headers.

sofakingdom

iTrader: (1)

Common sense.

Practicality.

What the man can find, on the ground, where he is, now, today.

Not a good idea even if somebody else did it.

I personally knew someone at one time, who was out skydiving one day, and his parachute failed to open; and he survived. Now, would it be A Good Idea for me to go around advising other people that it's OK to jump out of an airplane without a parachute, see here, I know for a fact this ONE guy did it and he's OK, I've even got a picture? This falls into the same class of things... just because ONE guy managed it ONCE, doesn't make it A Good Idea for this person.

ibmtech

iTrader: (1)

There is another thread going on at the same time where someone is going to put I believe a 440 dodge motor in his car.. I think if someone can do it, let them go for it.. It was different and I agree that not everyone should try it..

Street Lethal

iTrader: (16)

Go for it if that makes you happy. Swapping the 403 with the tranny from the 2nd gen and modifying the driveshaft, or simply getting an adapter plate for the 700R4 is essentially easy thanks to the internet, just be prepared to spend more if your out of the country. The 403 will run fine with the stock TBI system, just get larger injectors, and an adjustable fuel pressure regulator, and get it close to the 128 BLM target as possible. Haven't seen Joe on here in awhile, but he did a similar swap, but with an Olds 350. Here are some pics (your welcome in advance), and its' first start up video (see below). The guys on here mean well, as they don't want to see you make the same mistakes we all did when we first started so they're going to deter you a little, but it's your build though, and if you want to go with a 403, then so be it. Good luck...

Donnie(91rs)G

Question here guys, I have a 91 camaro with a 305 tbi and I'm wanting to run true duals off headers but my car has that b.s emmisions that has lines off the manifolds and a line that ran from my cat (no longer there) back up to motor, line is still in exhaust but I'm wanting to know can I take that california emissions off or will my computer freak ****? I wanna run headers and get rid of my manifolds is it possible?

Street Lethal

iTrader: (16)

You will be fine, I only noticed a slight surge at idle when doing that w/the '730 ECM's, but never with my old LO3's. If you pulled the EGR valve too though, be sure to disable it in the chip, as it will have an effect on your timing...

Donnie(91rs)G

How would I go about dis abling that?

Street Lethal

iTrader: (16)

Chip needs to be reprogrammed, and if your going to disable the EGR in the chip, then have the patcher doing the work disable the AIR while they're in there, too. If your going to keep the EGR functional though, then don't worry about disabling the AIR in the chip, just pull the smog pump, plug the exhaust manifolds with 1/4" plugs, and leave the chip alone...

Donnie(91rs)G

but how exactly do i reprogram the chip? i need to know what to buy or where to take it, and im going to run shorty headers and a new open element air filter so im going to eliminate everything i dont need but need to know how to reprogram it.

Donnie(91rs)G

after looking at how to reprogram the chip it seems like it would be a lot easier and cheaper just to leave the emissions control on there, way too much b.s to deal with buying a programmer and then going through all the steps then the possibility of it not even running right afterward

Street Lethal

iTrader: (16)

Emission equipment does nothing but take up room, it doesn't have that much of an effect with how the engine performs. Did so many before and afters at the track, and we're talkin not even a "tenth" in ET difference. It is really no big deal to have it done though, there are vendors out there that will burn you a chip to do whatever you want it to do. My autoprom is long gone, and I don't burn chips anymore, but there is nothing to it for the guys that are still working with proms. The engine will run fine so long as the chip is programmed for the correct injectors you are running. There's nothing to it...

Donnie(91rs)G

I live ouside of des moines iowa and idk any1 that will reprogram my chip for me and the problem is ill be self installing my headers then going to the exhaust shop to have my true duals put on and this car is my daily driver so I can't be driving it while its out of time because of the emissions control so if you have any ideas to what shops might do it I'm interested and a general price range thanks

Street Lethal

iTrader: (16)

I try not to link any information to those who will burn chips, as this website is essentially centered around the DIY community, and has always encouraged members to learn to do it for themselves. That being said, I will PM you some information that will at least help you find what you are looking for, because I don't like when members are left out in the cold...

Johnny Blaze

iTrader: (15)

Replacing a small boat anchor with a larger boat anchor seems counter productive to me.

Street Lethal

iTrader: (16)

A 4.351" bore, 3.385" stroke, 2.00" intake and 1.50" exhaust valve is hardly a boat anchor in my opinion. The weakness of the internal webbing of these blocks have always been questionable, but again, for a street engine you don't need to worry about stressing the engine at high RPM. It will do very well for what it is...

Johnny Blaze

iTrader: (15)

Then why is there hardly any aftermarket support for them?
Why are they not tearing up the local race track?

Ask anyone with a 2nd gen TA that came with a 403, they are turds.

Sure they have a big bore, and a short stroke, a combo that most engine builders will say is great for building RPMS and power, but the heads will not support that.

This is stragiht from a Major Olds site,

"The 403 was made from 1977 to 1979 and used across the Buick, Olds, Pontiac and Cadillac vehicle lines. It was also used in other applications like motor homes, boats and some industrial applications. It was sort of meant to replace the previous use of big block engines in the BOP line. Stock specs on a 1977-79 403 are: 185hp@3600 RPM, 320ft/lbs torque @2200 RPM, 4.351 x 3.385 bore/stroke, 8.0:1 compression ratio.

Big pistons and a short stroke are an excellent combination for a high-RPM engine, but here the other inherent 403 weakness comes into play: Windowed main webs, and to a lesser extent, siamesed cylinders. The bottom end of this block is not suitable for extended use at high rpm with very high cylinder pressure. "



In the case of swapping into a 3rd gen.

You are swapping in an engine that has less aftermarket support, meaning parts are harder to come by and more expensive.

Add the cost of custom exhaust, trans swap, and it just keeps sounding like less and less of a good idea.

Street Lethal

iTrader: (16)

Aftermarket support lol? I gave you the valve sizes in the heads, although the exhaust valves might be a tad larger, I honestly don't remember off hand. Compression came low with these engines, but the heads can always be cut to raise it where it needs to be. Plenty of aftermarket camshafts and intakes out there, and they can run on fuel injection or carburetion. What else do you need in terms of aftermarket? What...?

Are you kidding me? Plenty of Olds 403's racing here in e-town by me...

No, I don't need to ask anyone, I am asking you. Ever own a 403? Ever build one? I have, and they are decent engines for what they are, they just need to be cammed with a little more static compression just like every other engine that came from the late 70's, and they will make excellent power throughout the RPM band. The only problem with the 403's was the strength of the block, as that led people away from them. But again, provided there is adequate cooling, and RPM's don't get out of hand, they are excellent engines...

Johnny Blaze

iTrader: (15)

I built a 455 olds for a guy 2 years ago.

Never built a 403, but my brother had one in a 78 TA, and hated it. Limited choice of intakes and they were double sbc prices.

I could understand making one work, by swapping pistons and working the heads over to get a compression ratio that is decent, if it was a numbers matching car.

But swapping one into a non olds platform just seems like a waste of time and effort.

It will cost more then rebuilding a 305 or 350 and the results will be less then if they were put into the SBC.

Look at parts required.

There are plenty of off the shelf parts for sbc in 3rd gens.

You are going to spend MORE on headers, exhuast, accessory brackets, a Transmission that will bolt up, etc.....

While you may not agree with my thoughts, you can not deny that it will cost more to put an olds 403 in a 3rd gen f body, and what will the increase in cash get you?

Is the 403 olds a more efficent design?

Will it get better milage than a 305?

Will it make more HP and or torque then a 305?

Will it decrease front end weight?


Tell me, what are the benifits of the swap?

Street Lethal

iTrader: (16)

What do you mean "built"? You assembled a 455 for a guy? Any engine that displaces over 400 cubic inches has the potential to make excellent power. In the 403's case, it has a very short stroke. Port the stock heads and mill them down, add a better cam and stroke, and you will have a fire breathing 403 SBO for the street...

If you already built a 455 (which I HIGHLY doubt), then you should know how easy it is to work over the stock Oldsmobile cylinder heads. That right there is a tremendous savings over spending money on the Edelbrock heads for the SBO, and they flow incredible once they are ported. Camshafts cost money, decent one's do for that matter, and we all have to pay for quality. Plenty of intake manifolds out there as well. If we are going to get into the spending money issue, let's just say that its cheaper to build a Chevy than it is to build an Oldsmobile, but then again it is cheaper to build an Oldsmobile than it is to build a 3.8 GTR engine. It's an expensive hobby, and I don't nickel and dime my builds, especially those I build <cough> for people <cough>. Quality costs money...

Swapping pistons lol? Get a bone stock 403, pull the heads, port them out, cut them down to achieve a much better compression ratio over stock, cam, intake and carb and you have an excellent engine, no reason to go too crazy. Horsepower can give a crap which engine it is being squeezed out of, it only knows air and fuel. More air allows us the potential to burn more fuel, which equals horsepower. Power turns a prop, and a dyno measures the resistance. That's all it is...

Perhaps. I know for sure that I wouldn't do it, but hey it's his car, let him enjoy it. No reason for us to discourage new members. We can give an opinion once, but if their mind is made up, we shouldn't keep clouding the thread with dissent. If we don't want to help because of the direction they are going in, then avoid the thread...

He wants a 403, it isn't our project.

Not everybody is concerned with money, some people build engines simply for the fun of it. Some are not concerned about recouping expense. I for one only care that he enjoys his project, as that is what hot-rodding is...

Efficient design? Are you referring to combustion? Fuel atomization and quality ignition systems gives us our combustion efficiency. A fuel injection Mondello Oldsmobile engine is way more efficient than any SBC engine that came in a 3rd gen, what is your point...?



Now your suddenly "for" the 305? A few posts up you referred to it as a boat anchor...

Are you serious lol? Umm, yeah, it will...

If weight is now a concern for you, then invest in aluminum SBO heads...

Tell you what lmao? It isn't your car, and isn't your engine, and if you are against him doing the swap, then why even be in this thread arguing an irrelevant point thatg is taking you nowhere? I'm sure the BBC 3rd gen guys that are reading this now suddenly have a change of heart because of your wisdom, and will pull their 454's out immediately...

Johnny Blaze

iTrader: (15)

The op has already said he is going with a 350.

But yes, I 'built' a 455. We pulled the engine, striped it bare, polished crank journals, had it bored .030", I cleaned up the ports and had a 3 angle valve job done.

Why do you 'doubt' I have built an engine?

Rebuilt my first one over 20 years ago. Do I need to post a pic or me tourqing heads?
Do I need to post pics of me welding quarters on my 1955 Bel Air?

Those questions I posted were just attempts to figure out why swapping to an Olds would be a good idea.

A bbc is a different animal then a 403 olds for sure.

My "wisdom" is obviously missed. I was sipmly trying to state that a 403 olds is not a logical swap for a small block chevy in a platform that never came with a 403 olds.

I'm sure the 'big block guys' would understand.

I love the 427 in my belair, its no 403 olds!

About 2 years ago I sold the 427 out of my third gen, and am replacing it with a basically stock tpi 350.

Street Lethal

iTrader: (16)

Reread all "five" of the OP's posts. He ended his last post with OK! with an exclamation point. It sounded like he was getting frustrated to me, and was just humoring everyone because nobody was really helping him in his endeavor, rather everyone was trying to get him to drop the idea entirely. He hasn't said anything else since. Poor guy lol...

Johnny Blaze

iTrader: (15)

And, my first post came after his, simply stating that I thought it was not a good idea.

You then decided to pick a fight with me, and question my ability to have ever even assembled an engine?

Yeah, I can see why people get scared off.

2007xl50

Only made them a few years and rated at 180HP. They can be built up, but not worth it in a 3rd gen. Swap in a 350 or 400 SBC and be done and happy. The only way I would mess with a 403 is if I had a second gen TA that came with one and I was keeping the car original.

Johnny Blaze

iTrader: (15)

Dems fightin wurds.

Johnny Blaze

iTrader: (15)

Perhaps you should take your own advice.

Street Lethal

iTrader: (16)

Not really. People who know nothing about engine building, and who quote factory horsepower ratings are not to be taken seriously. He obviously knows very little in terms of the potential an engine already coming with a large 4.351" bore to start with has, so he recommends a 350 which will hit water at 4.125" or 400 that can't be taken out much more further than that. Offset ground crank to 422 with the right rods, and you will see an easy 600 horsepower with the right heads and cam...

Meh, but what do I know, stick with the 350, 400 and LSX crowd knowledge...

Street Lethal

iTrader: (16)

No, perhaps you should stop trolling somebody elses thread "trying" to make yourself sound intelligent, and post up an actual engine build. Do you have any video's that you can boast such self proclaimed knowledge? Any dyno runs? Ever actually break 13's in the 1/4 lol? Ever make more than 250 horsepower, even? Talk is cheap my friend, and those who know about engine building can see right through you, believe me, but for the sake of the moderators, as well as for this poor guys' thread, that is all I am going to say about your flawed concepts and knowledge. You want more, take it to PM...

Johnny Blaze

iTrader: (15)

I posted a simple reply, that followed thr same sentament as most others in this thread.
You then chose to attack me, and say ice never even built an engine.
I was simply defending myself.
I have been on this forum just as long as you.
I did know I had to post my resume after each post.

You can see my latest build a 1969 C10 on pro toting.con
same user name.
Got a 1971 camaro to replace it, as my daily driver.
Haven't "broke 13's, lol" local track is 1/8th mile, but the 55 ran consistant 6.80's last time out. Took it apart, did a ton of bodywork, will be shooting base coat on real soon.

Guess I'll start a build thread for it.

Stunt_Man

Hey. I bought 350 in good price. How to decipher the numbers?
3970010 on rear side
K0524DRB and 19120292 on front side.

sofakingdom

iTrader: (1)

3970010 = the single most common 350 block ever made; from 1969 to 1980

The K number tells what kind of car the block was originally installed in. Would tell you what size carb it used to have (2 or 4-bbl), approximately what the carb & distributor calibration was, and such as that. The vast majority of motors built with that block had 993, 624, 882, or 339 heads; a few had 186 or 041; there were a few other #s but that covers probably 98% of all those motors. Very near 100% of them would have had the 929 cam. Won't tell you anything at all about what the motor IS NOW...

That block casting was used in everything from 160 HP phone company work vans to Z28s and Vettes.

You can look up the codes here: http://www.nastyz28.com/chevy-engine...ngs.php#suffix Don't be surprised if it comes up something you'd be ashamed of. But don't worry, what THE ENGINE that it was part of when new, is not related in any manner way shape or form to THE ENGINE that's built out of it now, unless it's COMPLETELY untouched and in absolutely original condition... which the odds of that, for a 70s block, are probably less than 1 in 100,000.

If you look right next to the casting number, there will be a 4 character code, 1 letter and 3 numbers. It will look something like B126. It's the casting date. The example would be the 12th day of the Bth month (2nd, Feb) in a year ending in 6; which would be 1976 for that casting.

The stamping is worthless if the motor has been TOUCHED, let alone rebuilt. All blocks are equal, as far as anything that code can tell you; it carries no information any more. The other number, I don't recognize; if it's stamped along with that other one, it's the last 8 of the VIN of the vehicle it came in.

Stunt_Man

thx! i have what i need

2007xl50

Oh yeah, welcome to the site man. I guess there is only one person who knows stuff on here and the rest of us are just dumb, but hey-we will still try to help when we can-sorry about all the internet tuff guy stuff going on in your thred. Hope the swap goes well for you.