Confuzed1

iTrader: (4)

Just posted this to clarify some questions on a swap I'm in the middle of.

I'm swapping from a '83 305 to a 74-78 400 SBC. I know there should be no probs with the basic install, such as mounting, but are there any diffs between the 305 and 400 I should be aware of? The 400 is internally balanced, so bolting up the T-5 should be easy.

I'm still trying to figure out which throttle cable and cruise control cable brackets to buy. I have only found throttle brackets so far.

I've heard the temp sensor may interfere with the headers on the 400, but it looks like the shop has a brass extension screwed into the hole, so hopefully that will be a non-issue.

I have also removed my computer and ECM harness without having to cut any wires. I was amazed at how easy that was! Also changed out the motor and trans mounts. So anyways, you guys that swapped up to the 400's....anything else I should look into before dropping this in the car?? Thx in advance!

EDIT: Oh, and the 400 has a driver's side oil dipstick. I doubt it will clear the headers. Are the flexible ones good for this?

Air_Adam

Yep, check out Lokar, they make flexible dipstick sets. I think they cost around $40 or so.

As for differences between the 305 and 400, I'd check the starter bolt pattern. When I installed my '79 350 in place of my '83 305, the bolt pattern was different, and a new hole had to be tapped into the 350 for it to work right.

What oil pan do you plan to use? You might need to find one that will fit your chassis, but also work with a block that has a drivers side dipstick. Again, the same thing with my 350. I got a pan from a '79 Z28 (Any pre-80 SBC-powered 2ndgen pan will work) and it fit great. I don't know if any other pans will work, but I know the 2ndgen pan will work fine. It did for me.

Why can't you use the original throttle cable and cruise control brackets?

If you are using the mechanical linkage on the T5, better make sure your 400 has a threaded hole in the side of the block above the oil filter boss for the ball joint thingy.

I don't really see why the temp sensor (fan or gauge) would interfere with the headers... they would be in the same place as on any other SBC, wouldn't they?

You prolly wanna make sure your cooling system is in primo condition too, because 400" is gonna make alot more heat than only 305" will.

TPIMarow6.6

I recently swaped a 400 into my car, a few things to get first is the balancer for the flywheel, it goes between the flywheel(Can buy them at engine shops) and the crank , its because the 400's are EXTERNALLY balance, i didnt know if you made a typo or what not, but anyways, make sure you use the 400 harmonic balancer, or crank balancer because it is made specifically for the 400 and if you have an aftermarket timing tab then make sure its the right one for the engine, 305 timing cover wont work. also the starter problem will be an issue, on mine it only had one pattern and it wasnt the right one, because if you look at different starters the bendix shaft and cone are placed more in the center of the bolt holes where other chevy's are offset more, that will be a problem also getting a starter with a small enough cone to fit into your T-5 bellhousing, and if its a T-5 and not a T10 he should have hydraulic clutch linkage. i had tap a hole in my block for the starter and i had to buy a starter from a 92 camaro and i ground down the head so it would fit into the housing. if your block(which i think it will) might have both patterns for the starter, dont mistaken the extra hole close to the oil pan as a bolt hole, cause its not. lol as for the dipstick, i used stock manifolds on mine for a short time and couldnt use the dipstick because the exhaust outlet came out right in front of it, so i bought a pair of SLP 1 3/4 headers and now the stock short dipstick works perfectly. so if you get headers they will be just fine. as for the throttle brackets depending on the intake the stock ones should work fine like Air_Adam said, also make sure you go buy a pilot bearing for the end of your crankshaft, and be carefull putting it in you dont want to mush the end,then youll have to use a rat tail(file) and grind down the end, also the oil pan issue, i used the stock one from a 73 caprice convert. and it worked perfect. also about the coolant temp sensor, if your going to use stock 400 heads(72-76 CC low comp) then the threads will be different, they are coarse thread and the 305's(at least my 85 is) fine threaded, maybe they make an adapter for it. sorry for the long post but id figure id help you out. let me know how its going for you.

--Andrew

Confuzed1

iTrader: (4)

Thanks Air_Adam!!

As soon as I read this, I went out and looked...I don't have the hole for the clutch crossbar!!

But, on a good note, I can clearly see an indention of where it supposed to be. Looks like I'll have to drill and tap it out... that was one thing I never thought of!

My stock cable brackets won't work because the carb sits up higher on this intake. I already had to tweak (bend) them around when I got the Weiand intake once. This intake is a little taller.

I have a 7 QT pan on it that should fit - drivers side dipstick. I got a high volume water pump and a pretty new radiator so I don't think I'll overheat. Again thx for the heads-up!! I think you saved me from a lot of pain!! No way to drill that hole with the engine in.

TPIMarow6.6 : Thanks for the info! Sorry, I meant that I had MY 400 internally balanced when it was built. lol

The only thing stock in the bottom end is the block. I also had them verify the bolt holes for the starter...thier there.

I have a stock type oil tube, and I already have headers so I'll see if it'll work!

I'm running Dart heads, but for some reason the shop put this brass looking extension piece in the temp sensor hole. Maybe it's an adapter like you say. Makes sense!! - I knew about the starter thing. I had the shop ensure the holes were there for a normal 350 starter..

A lot of good info on this post!! I appreciate it! Anything else I should look into?

Looks like I need to break out the drill....

Air_Adam

Yea, I didn't know about the crossbar **** either untill late in the swap... but I got lucky because my 350 already had one in it.

And yea, it would make sense that the plug in your head could be an adapter. I had to use an adapter to make my stock fan switch sensor thread into my old '79 882 heads.

I can't think of anything else right now, but if anything else comes to mind, I'll post it here.

Good luck!

Confuzed1

iTrader: (4)

I could have sworn it would fit when I ordered it. My oil pan is interfering with my Y-pipe.

Turns out the drivers side header tweaks inward towards the oil pan at the collector, and the "kicked out" portion of the pan won't allow me to bolt up my Y-pipe.

Looks like the only way to get around it is to have some type of "custom" Y-pipe made. Guess I'll have to see if it's worth it. I know the pan wasn't cheap, and I'd really hate the thought of not being able to use it.....this s*cks.

Air_Adam

Whats the interference problem? Maybe you can modify the y-pipe you have with a torch to bend it a little to fit right.

Confuzed1

iTrader: (4)

Let me see if I can post a pic....


Well - guess file is too big. Anyways I think it may end up being too sharp of a bend if I try torching on the Y-pipe at home. Def. need the tools, like a tube bender.

Air_Adam

Ick... yea, I'd just have an exhaust shop either modify the one you have or make you a new one. Sounds like thats your only option, by the sound of things.

Confuzed1

iTrader: (4)

Just got the engine in the car. I ended up swapping to a stock pan. The more I thought about how tight the bend would have to be, and how it would flow afterwards, I decided to take it off.

Of course I lose the benifit of a windage tray in doing so.

Now I'll end up selling it for a loss.

But - so far everything's bolting back up nicely!!

Air_Adam

Too bad about the pan, but good to hear everything else is working out for you

I probably shouldn't be saying this here, but if you aren't going to be re-using the L69 scoops and flexible ducts, would you wanna help me out with a set? PM me if you you are interested.

Confuzed1

iTrader: (4)

Just figured out finally how to post pics. Here's one of the engine a few weeks back. It's finally in the car, and should hear it run by the end of this week I hope.

The new one:

Confuzed1

iTrader: (4)

The L69 that came out.....which still runs awesome BTW.

Confuzed1

iTrader: (4)

And here's why I had to get rid of the nice oil pan....
You can also see the missing hole for the crossbar on the clutch too.

Air_Adam

What manifold is that on the L69? Doesn't look stock, but has the stock EGR location...

five7kid

iTrader: (14)

From his sig: "Weiand Plus intake".

Air_Adam

Riley's35089rs+

Here is an alternate to drilling...I bought one and it works great!
http://cgi.ebay.com/ebaymotors/ws/eB...EBWN%3AIT&rd=1

Riley's35089rs+

another... these guys have great customer service!!
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2476175768

Got it in 3 days!!

Confuzed1

iTrader: (4)

Looks like your car's coming along Riley!! - Let me know how it's going.

I didn't have to drill any holes for my starter. Luckily the right ones were already there.

On another note....My 406 is now ALIVE!! Man, it has a choppy idle!!

Got it running yesterday, and I attempted to tune it. This engine has more cam than I'm used to, so I had a few problems setting up the timing/carb.

Initially I was trying to set the timing at 10 degrees advanced, which I think is were I was going wrong. It wanted to run hot, and the exhaust had a "popping" sound.

I then looked closely at my dyno sheet to see where it was set (under optimal conditions), and it said 38 degrees advanced. I tried that, and it ran smoother and cooler.

Only problem is when I set it that much advanced, the car doesn't want to start. The starter tries - but cant turn it. So I ended up backing the timing at idle down to aound 28 degrees and now it will barely start.

Does that sound right to you guys running a simular setup?? Should it be that advanced?

Do I just need to get a high torque starter or am I timing this thing wrong? Or what??

I haven't had it on the road yet because I have a few small things to do to it, but when I blip the throttle it really winds up fast. Seems real promising!!

Thx for any help in advance.

EDIT: Hey Riley....I looked at the starters you put the link in for. Isn't the t-5 flywheel 158 teeth?? So neither of those will fit my car right??

Confuzed1

iTrader: (4)

TTT....anyone??

RB83L69

You'll want a high-torque starter. BTDT.

Get one of the ones that has both bolt patterns (4 holes) on it.

I ended up with the CVR one. Works great on my 400; and 305 too.

Your timing is going to want to be somewhere around 36 degrees static + centrifugal when you get it dialed in. You'll just have to find the optimum combination of the 2. Usually 10 or 12 static and 24-28 of centrifugal starting at about 1200 and all in by 2800 is about good. Then you'll want 10 or 12 of vacuum advance on top of that.

Make sure you have the vac adv disconnected when you're setting the static; and hook it up to the ported source, as a start to your tuning.

Confuzed1

iTrader: (4)

Hey, thanks RB!....

A couple of questions on that though. What do you mean by "36 degrees static"?

I assume that's initial timing? If I time it there, it runs at it's smoothest but I can't shut it down cause it won't start. The starter tries, but it acts like the engine isn't timed right. As said above, the engine was dialed in on the dyno, and the top of the sheet says 38 dgrees BTDC...but that's using long tube headers etc...but it still runs smoothest close to that even with my exhaust. (TES/Hooker)

And when you say +centrifugal, I assume that means the spring/counterweights for the mechanical advance....the shop already set those up I think. I don't have vacuum advance, just mechanical.

What does "BTDT" mean??

And one more thing...I know a few of you guys have or are running this cam. The idle on mine is NOT what you would consider smooth. Normal???

Regardless, looks like I'll order another starter in the morning. So much for the "lifetime" warrenty from Autozone!! lol

BTW...Thx alot for your help and advice during this long expensive project RB....as well as others. Hope to meet up with you guys one of these days!

RB83L69

36 degreees "total" timing, including the initial or static setting, plus the centrifugal advance

As I described, a street motor will usually run best with 10 or 12 or 14 degrees of initial timing, and then however much centrifugal to take it up to where it makes the most power, which is usually around 36 degrees. 38 degrees sounds believable.

BTDT = Been There Done That

I had that cam in a 400; I thought it was pretty smooth, actually. I guess that's a matter of judgement. It idled considerably smoother than the 282 solid that it replaced, even though they have the same .050" duration and very similar lift.

Vacuum advance isn't necessary for a strip car. But it REALLY helps gas mileage in a car that sees any significant cruising duty. I's suggest adding it.

As far as the starter, the design of the Delco-Remy starter is very poor for producing high torque. In fact, it's just a poor design, period. You could get one of those to work factory-perfect and it still wouldn't have enough nads to turn that motor over. You simply need a starter that's better designed to begin with.

The aftermarket mini-starters are almost all biult out of either a Nippondenso motor (my CVR is that one) or the Hitachi motor (the Powermaster and Summit one are that kind). Either one seems to be so far superior to the old Delco design from the 30s, that you won't recognize how your car starts. The LT1 starter is of a similarly improved design.

five7kid

iTrader: (14)

Your dyno sheet meant total timing - initial plus centrifical/mechanical. The full advance. You certainly don't want to set your "idle" advance there, because then the centrifical will be added to that.

Do you have timing tape or a marked damper? I can't tell from your pictures. If not, you'll need a timing light with advance feature - you dial-in what advance you want, and then set the timing so the damper mark lines up with the "0" mark on the timing tab.

You should set the timing with the distributor making full advance. That means you need to rev the motor up until the distributor doesn't advance any more, then adjust the timing. If you don't have timing tape or a marked damper, spend your money on an advance timing light before you go out and get a high torque starter.

The only other option is to know how much advance your distributor is making and set the idle advance that many degrees below 38.

Riley's35089rs+

that starter is for the 168 tooth flywheel and it works great on my setup...I just tuned and timed mine today, I also have a very choppy Idle Especially for a roller. It wants to Idle around 1000 rpm this motor would have no street manners at all...I love the sound...the inside of the car is gutted now and everything rattles like a can full of rocks
I am very happy, and I should get some track time in real soon.

Confuzed1

iTrader: (4)

RB and 5-7:
So from what I’m gathering here – I have some more tuning to do. The manual that came with the carb said most performance street engines need around 18-24 degrees advance for the initial timing. I already know my car will not run right at all with 8-10 degrees of static advance.

That’s what I tried yesterday. It tended to run pretty hot (220-230), was really rough, and the fan pretty much ran constant. There was also a “popping” noise coming from the exhaust that I never had with the 305, so I knew it had to be the timing causing those symptoms. The lowest it seems I can set the timing for and have any kind of smooth idle is around 20 degrees.

I do have a timing light, although it doesn’t have an advance feature. The balancer is marked at TDC and goes up to at least 40 degrees advanced. The pointer was spot welded to the cover by the builder.

So I guess this is what I’ll do. Set the initial timing at around 20 degrees and rev and hold it at around 3500 RPM’s to see where the timing ends up. So that reading should be around 36-38 degrees in full advance right?? I have a bad feeling this could get ugly unless my distributor only advances 18 additional degrees when I rev it. Sounds like that will leave me at idle with a setting it won’t run on. I’ll find out tomorrow.

Riley:
Glad to hear yours is running too!! Now you can travel up this way and get mine tuned! lol
I have interior (some) in my car, and it still sounds like a box of rocks like yours! Problem is, my engine's not near as radical as yours. I hope I can figure mine out soon.

No one I know has dealt with trying to tune an engine set up like mine, so this is pretty much the only place I can turn to and ask some experienced guys on how to get this thing right.

Confuzed1

iTrader: (4)

Well, I now have the static timing set at 18 degrees BTDC, I have the carb adjusted to idle OK and total advance is set at 38 degrees. Idle set at 850-900

Problem seems to be engine temp now. running just a tad under 240 and that's with the fan running constantly. Of course that's also with it idling after 30 minutes or so. I think it would be worse with the hood on. I haven't driven it yet.

Something's just not right, and I cant figure out what it is. I did replace the temp sender during the swap. I have no reason to believe that the gage is lying because of the fan running. Oil is clean and no leaks anywhere.

I don't hear any missing at all when it's revved up. Smoothes right out. Still pretty choppy at idle though. Any ideas?

five7kid

iTrader: (14)

You might want to consider getting a vacuum advance-type distributor. You can run less initial timing (easier on the starter) because the vacuum advance will come on after starting at idle if you have it hooked to manifold vacuum. And, believe it or not, more timing at idle/cruise can help the engine run cooler.

Hopefully your pump, radiator, thermostat, & fan are up to snuff. And the heads were drilled for the steam holes.

RB83L69

A brand-new motor will typically run somewhat hot for the first few miles. It should settle down within 5 or 10k though.

Like five7 said, a dist with vacuum advance is usually better for a street driven car. Vacuum advance gives you 10-15° of additional advance when the throttles are open and the engine is under light load (high vacuum) which corresponds to cruising conditions. It can be worth as much as several miles to the gallon. And, like he said, more advance while cruising will help it run cooler, from being more efficient at extracting the heat energy from the combusted gases and turning it into work (which is also where the gas mileage improvement comes from).

I don't recall whether you're still using the stock starter; if you are, get rid of it, and put a good gear-reduction one on there. You won't believe the difference.

Confuzed1

iTrader: (4)

5-7:
Yes I know a vacuum advance will give me less initial timing on a startup, but I didn't think running a mech. adv. dist. would have this much of an impact. Radiator, waterpump are new. Entire cooling system practically new. Not sure if I even have a thermostat in it though - I have'nt had the water neck off yet to see. And yes, steam holes were drilled supposedly. At least that's what the spec sheet says.
If I continue to have this temp problem (and I think I will), I'll try a vacuum advance dist. Really pi**sses me off that the builder was animate about not running a vac. adv dist, and now it's looking like I might have to. Another 240 bucks I paid for this distributor going to waste...for nothing. I'll just put it next to the $150 dollar oil pan I couldn't use either. I think a call to the builder is in order to see if he'll give me credit if I return these.
But you're right, this thing sucks down some gas! I've went through over 1/2 tank of gas trying to just tune it the past three days.

RB -

Yes I am still running a stock starter for now. I just have'nt bothered ordering one until I get the engine straight. But I will def. get one within a few days. Now that I have adv. down to 18 degrees initial, it starts but just barely.

So by what I'm gathering by both your response and 5-7's, I shouldn't be too terribly concerned about the temps for now? My 305 was a full rebuild and I didn't have these problems...but it was still CCC....not now.

Only things I have left to do is hook up 2 vacuum lines, brake booster, and figure out what I need to do with the hoses from the carbon canister. Oh, and find a air cleaner that will fit under the stock hood I still need to put back on also.

Then I'll give it a test run around the block and see if any of this has been worth it!

RB83L69

Most street distributors have both vacuum and mechanical advance.... it's not either/or. For normal highway operation you need both. You don't need either for a race car alot of the time.

Riley's35089rs+

That seems a little bit warm to me, but what do I know. Im running a mechanical fan..and just a washer in the thermostat. I ran it today on the road pretty hared..the warmest she got was 180, What a fun ride that was I might add. our LT-1 cant touch it!

Confuzed1

iTrader: (4)

Yeah, I know most street distributors use a combination of vac. for initial advance, then a mechanical takes it from there. - Thanks!

RB83L69

No, not exactly.... all distributors use "initial" or "static" which is determined by where the dist is installed (rotated) in the motor; they use "mechanical" (centrifugal) advance to change the timing according to engine RPM; and they use vacuum advance to change the timing according to engine load. The end result of all 3 settings or calibrations produces the advance curve that the ignition system actually supplies to the engine.