[77HANDMEDOWN]

I have a 77 T/A with the lower powered l78. The car was all stock when I got it from my Dad about 4 years ago except for the k&n filter. Lol FINALLY done with all my suspension work and all 4 wheel LS1 disc brake conversion. Car handles and stops pretty dang good for what it is. Now I am looking to tinker with the motor a little.

I want to build a 400 based stroker at some point but am looking to have fun with this motor a little first. It has 80k on it. I have a set of Dougs long tubes for it and a pypes exhaust. yes I have committed to d ports for the long haul. Before the headers go on I want to reseal some old oil leaks and remove some emissions equip like the heat riser and EGR and so on. A carb rebuild and ignition tune up are a given. While the valve covers are off I want to adjust the valves and check all the push rods. I was looking at how cheap a factory type timing sets are or how cheap the summit 2801 cam and lifter set is. It seems like for around $200 including gaskets I could reseal some leaks and maybe make a little more power.

I am not looking for huge power just a little shot in the arm to have fun with while I build another engine on the side. My sister and I both drove the car 20 years ago in high school and beat on it. You think it is safe to try and wake it up a little or should I worry? Also aside from setting the timing what else should I do to the distributor? It has a new module cap and rotor but that is it.

Any thoughts concerns or advice is appreciated. Oh it is a th350 with 3.42 gears and stock converter.

[ponyakr]

I wouldn't spend any money on a new cam unless the old one has some lobes going flat. But if you decide to go with a new cam, that 2801 may not be the best choice. I think it is recommended for 9:1 compression, or higher. Also, it has more lift than stock, so will need new valve springs. One thing leads to another.

If you decide to go with a new cam, I'd recommend a Lunati Voodoo 256, with the stock converter, or a 262 with a 2400-2600 converter. You'll also need some good springs, like the Crower 68404-16.

http://www.ebay.com/itm/Cloyes-Gear-...970e3e&vxp=mtr

http://www.race-mart.com/Lunati-LTI-10510701LK.html

http://www.summitracing.com/parts/cr...f3QaAq4Z8P8HAQ

There is some performance to be gained by recurving your dist. By using at least one lighter spring, from one of the recurve kits, you can lower the rpm at which your dist achieves total timing. Most say you want all your timing advance in by 3000rpm. Some say even a bit lower.

I'll leave the details of the dist timing to the experts. I personally would not spend any more $ on a "557" block engine than I had to. Since you're planning on a stroker build anyhow, I'd put the $ into that build, instead of your present engine.

These are just my opinions, and will not be the same as some others.

[77HANDMEDOWN]

I just thought the 2801 cam was ok with stock springs and low compression. I totally know about the one thing leads to another deal. I definitely don't want to go much further that what I described. It just seems really cheap so I figured why not. I know the 557 is not a good block to build on.

[b-man]

Put the 2800 cam in it.

Better match for the low-compression 400 and easier on the current valve springs.

Had one in a 400 with 8.2:1 and it was a pretty strong runner with a 3.23 rear gear and TH400.

[PunchT37]

Or the crower 60240 with stock springs.

http://www.crower.com/catalogsearch/...KRrGBi&q=60240

[1971WARBIRD]

when I bought my 78 TA new, a set of 1.65 rockers, a carb tune, and recurving the distributer made a difference you could feel.

the stock cam has low enough lift that I didn't have any problems with hitting heads.

[Squidward]

I like the 2800 or Crower 60240 suggestions if you plan on sticking with stock springs. If you are going to get aftermarket springs, then I would use either of the two Lunati offerings suggested.

If you go gaskets/seals/cam/lifters/chain, etc, there was a timing chain thread here months ago. For the budget minded builder, the NAPA chain/gear set got high recommendations.

[steve25]

The first things you want to do just to drive it since it has 80k on are these!

1) replace the timing chain a gears, as even with this motors small amount of valve lift it is still a interference fit motor, and if the Chain fails you will find out what interference fit means in a hurry!

2) replace the stock fuel pump and any factory rubber fuel lines on the car since they where not made to handle today's Alky cut pump gas.

3) Along with the Headers if you have a true duel exh system on the car then you motor is going to be running lean on secondary side at full throttle , so you need richer secondary metering rods in that Carb, like 10 to 12%.

[77HANDMEDOWN]

Thanks for the replies. I think I got the 2801 and the 2800 summit cams mixed up when typing.

I think I have pretty realistic goals and expectations. Just want everything to be reliable and hopefully stop leaking.

[HWYSTR455]

The '77 L78 used the 278/298 cam, and with 1.5s, lift is .364/.405 . A simple change to 1.65s would almost be like a cam change, but you need to enlarge the pushrod hole in 6x4s.

I've seen folks do that with heads on the car, but if I personally were to try it, I would pull the intake and valley pan, so there's a straight shot to clean up. If you go to that trouble, might as well change the cam.

As I recall, stock heads can support lift up to about .469 before there's issues. Then there's problems with not only the pushrod, but the rocker to retainer clearance too.

The L78 was a 200hp version, and with a little tuning, think you could prob get another 20-30 out of it. If you wanted a little more, than step up to the 1.65s. I prob wouldn't put too much effort into that engine and just save for the new.

If by chance you were still thinking of a cam, since it's a low compression engine, choose one with short seat timing, to help dynamic CR.

If you want to do the cam, and you need to go through the heads, you would be better off getting a set of already done heads of the 72cc variety. That would bump the SCR, you would have a better cam selection, but then you will start testing the strength of the 557 blocks.

And there starts your domino effect....

.

[beertracker]

Originally Posted by PunchT37

Or the crower 60240 with stock springs.

http://www.crower.com/catalogsearch/...KRrGBi&q=60240

Is this a non-symmetrical lobed cam (fast opening\slow close)? I couldn't tell from the link. bt

[track73]

I had the Summit 2800 cam in my low compression 400 with headers and it was a hoot to drive. Let out the clutch and go. Low end was great for around town.

[Bob Dillon]

Forget the current engine and drive it. Put the money into the new one.

I have the Summit 2800 in my Grandville and it pulls like a locomotive, but I also have Crane 1.65 roller rockers and valve springs on 6X-8 heads. Idles smoothly at 700 rpm and pulls 19" vacuum at idle.

My rule on street camshafts is to pick the one you think is ideal and then check the order form for the next milder cam. It's always worked for me.

[ponyakr]

The 60240 is not a "steep ramp" cam, like the CC XE and Voodoo series cams. The Crower ads say this cam works best with 9.5:1 CR.

http://www.cnc-motorsports.com/crowe...-camshaft.html

One way to get the effects of steep ramp cam, without the increase in lift, is to use an 068 clone, such as a Melling SPC-7, and Rhoads lifters. When puttering around, under 3000 rpm, you'll have less duration and lift. Then passed 3500 or so, the Rhoads will restore full cam lift and dur.

http://www.ebay.com/itm/Engine-Camsh...e992bc&vxp=mtr

http://www.summitracing.com/parts/rh...w/make/pontiac

Yes, I know Jim Hand didn't recommend Rhoads with a cam that small. But, I'm talkin about a specific app here. The purpose is to come up with a low lift cam, for a low comp engine, that will increase performance slightly, without changing valve springs. This combo might work.

I put an 068 with Rhoads, in a low buck, hi comp 400, stock 13" converter, and TJ won the biggest race of the year with it at the Prescott, Ark track, in '77. No, it wasn't the best possible cam/lifter/converter combo, but it ran smooth and consistent enuff to win a big bracket race.

[PunchT37]

I have installed the 60240 in a bone stock '79 T/A PWH 400. Never pulled the heads. Cam is a pussycat. Smooth idle. Quits pulling at 5000 though.

[STEELCITYFIREBIRD]

I'd do a compression and leak down test before considering doing any internal mods. And before doing them I'd run some combustion chamber/fuel system cleaner and some hard acceleration runs on it to try and clean out some of the carbon build up. At 80k, there is wear on the rings, timing set, and build up on the valves. Those test will show if you have a healthy air pump(engine). If it is pumping/chambers sealed well then put a $# on what your willing to put into it and go from there.
The larger long timing cover bolts tend to get stuck in the cover and break off. Project scope creep can set in real quick.
I've seen many a cam change turn into a full rebuild on higher mileage engines.

[77HANDMEDOWN]

Great info here guys thanks! I understand some of you not thinking I should waste money on this smogger. I don't have the #'s anymore but I did a compression and cylinder leak down a couple of yours ago. Which is a couple thousand miles ago. All cylinders were even and compression was pretty high for what it is. I have NEVER seen even a puff of smoke out of this thing either.

I went ahead and got the 2800 cam and lifter set from Summit as well as a new t-stat, gaskets, plugs etc. I found a Cloyes timing set for $19 on Amazon. If all goes well I am going to drive it a while like this. It gives me time to replace some wiring and clean up some clutter in the engine bay. I am also going to do some revisions to the factory a/c system. Basically have a driver while I am putting together a nicer engine as I can on the side.

I am just so glad to drive it I don't care how fast it is. I thought I would never finish brakes and suspension stuff.

[Squidward]

Excellent! I hope it goes well. Whatever keeps you driving is the most bang for the buck.

[rexs73gto]

1 thing I found in your statement about your car you said it had 3:42 rear gears, ?? are you sure of that or did you put them in yourself. I believe that the biggest gear set you could get in 77 was the 3:23's, or it may have even been 3:08's But i don't believe that you could get the 3:42's in 77 from the factory. I think the last year for the 3:42's were/was 74 ?? I may be wrong but please check that out for sure as your next engine or your new engine build for the car will depend on that.

[1971WARBIRD]

http://www.78ta.com/rearcodes.php


going by this 74 is the last year for factory installed 3.42s until they were brought back in 1979, but doesn't mean someone could not have installed later.