349 CI on the cheap

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6,500 is where the power peaks and then falls quickly, so turning it any harder is not necessary. It would go higher but the cam would have to have alot more lift and then the compression ratio would have to come down some. Or a meeting of the parts would happen. Also too the engine is cammed for the heads and the flow that they have. So adding a larger cam to this engine would be a waste. Thats whats so nice about this engine, it makes alot of HP and TQ without the high $$$$$ parts. I'm going to be doing one for a customer for the street with 10.5 compression next month.

Love this thread.

Let us know how the customers car goes as well if he runs it!

Keep up the mad work bobby!
 
I don't think that he will run the car on the track, as it's going into a very nice 74 Cuda, B5 blue with white interior. He mainly wants it for street use and have the power to kick some butt if need be.
 
Hey don't worry as were in the process of getting one ready for a buddy of mines duster, that the 322 is in and then we'll be able to give you what it should do in a street car.
 
Well Friday looks good weather wise and I've been ready. Just went out and fired the car again and man it had a big smile on its face. The weather for Friday is showing to be 92* and I'm sure about 80% humidity, so the corrected altitude will be some where in the 3800 to 4200 ft elevation, but who knows. I'll let you all know what it does on Saturday.
 
Well as I figured that there would be some tuning to be done, and there was. The first pass the engine was way, way too rich for the air that we had last night. So I dejetted the front and made another pass. The first pass was a 7.73, the second was a 7.63 so I was in the right direction. Then on the third pass I dejetted the rear jets and left the front alone. I figured that I would try to give the engine a little help as the track was hooking real hard. So I put more air in the tires from 11.5 to 12.5 lbs.. The car responded by running 7.61. Then I put another 1lbs. of air in and retarded the timing just a few degrees so now I'm at 13.5 lbs of air. I go back and make another pass and the car runs 7.478. At this point time trials are comming to a end so I had to leave things as they were.

I go in for the run for the money (basically another time run but paid for) in this closest to the dial in without braking out or red lighting wins the money. In this you only have 1 shot at it. So I dial in at 7.47 and the car runs a 7.493. But they didn't have super pro so I backed up to foot brake class. Figuring that the car would be slower I dial in a 7.54 and to my surprise the car decides to run like a scalded dog. I drive it to about 500 ft or so and lift and hit the brakes thinking that I'm surly not braking out and the car runs a 7.49 on a 7.54. Man I killed 13 mph.

Being how much that I dropped it by and how far I went under the dial, this thing was on a low 7.30 run or quicker. So in the 3rd round I dial a 7.35, the car leaves with the wheels up and man this thing is on another good run. The only thing that I was thinking of was just dont brakeout. So I'm shifting the gears and this thing is pulling hard, I get it to high gear and something feels like it's holding back or putting a heavy drag on something. I get about 80 feet from the finish line and the car locks the wheels up and I'm sliding across the finish line. The car is now stopped about 100 feet past the finish. I cut all the swiches off and get out. The emergency crew comes hauling butt to me to see if I was OK. I was fine but don't know what happened, some said that I broke a rearend, and others said that they could see sparks comming out from under the car, and yet some others said that there were bright blue flames comming out from the hedders. To me from inside the car it acted like the timing was way too far retarded, but I knew that this wasn't the problem, but it sounded like this. Popping and back firing out the exh. But anyway something broke. I was thinking how happy I was to have just put a new transmission blanket on the car. Later after talking to some spectators I knew that the rear end was fine as the car rolls easy and no clunking. So now it has to be either in the engine or transmission. The thing is it never dropped a ounce of fluid from anywhere. Oil pressure was up and the temp was fine, but something has the engine locked where it won't turn over. As of this time I'm not sure what happened, but I'll have a look today to see if I can see anything. When we looked last night everything looked normal. But where were the sparks comming from. I'm thinking that maybe the converter bolts were comming loose and one of them lodged between the block and the flywheel. But I'll have to get it apart one day this week and see, if I get the time.

From others that I was talking to, they figure something in the transmission gave up. As the engine was running to smooth and pulling to hard. But as of now everything has to come apart and be checked. Including the engine, transmission, and rear end. I'm not taking any chances of this happening again. Next time I may not be as lucky. Good thing I have a fresh Big block and trans. ready, so guess whats going in next. I'll let everyone know what I find when I find something.
 
Glad you're alright is the main thing. If it in the trans it really had to lock down hard to start a slide that long. I bet that was a scary little trip.
 
Marlan,
It went from running somewhere around 90-100 mph to 0 quick. Believe me it got my full attention. We took the plugs out today and found that every plug was colsed up and silver looking, like they were coated like alumni-coating them. But how, when they can't be hit by the pistons did they get this way? Well after more inspection it burned every piston in every cylinder, and between the pistons comming apart and the heat in the chambers it kept the valve open on #2 cylinder which when you have close tolerences isn't a pretty site. So now I know where the sparks came from and the bright flashes out of the hedders.

I'd like to have aluminum heads but not this way, although they were coated very nicely. So next time I'm going to drop the compression down a bit and run a bit thicker head gasket, maybe a bigger chamber head.

I wonder if now that they are coated, that they will dissapate heat quicker? LOL. Oh well I'll fix the engine when I can and try it again. But it will be the end of this year or first part of next year, as the Big block will be going in, in the next few weeks. Hey it's nothing that can't be fixed, it's just going to take some time. And as this is play work must come first.

Thanks for you concern!
 
Crazy!
Glad to hear your ok though bobby.

Your best time that day,
what would that equate to on the quarter mile roughly?
 
nemesis,
The 7.478 would be a 11.50 or so. But had I not lifted it would have run a low 7.30 or upper 7.20 with ease. But you have to keep in mind that this was only the first runs on the engine, and it was still freeing up and the tune up wasn't where it really need to be. Also to the air temp. went from upwards of 100* to upper 70's to low 80's in a few hours, so trying to keep the tuneup right and on the first day without enough time in between rounds may have caused the problem.

The 7.30 or 7.20 that it may have run would have put the engine running in the low 11's. A low compression version of this engine should be able to run upper 11's with ease. Keep in mind also that I was running a .473/.494 lift hyd. cam with 107* of overlap. When I redo the engine I may change the camshaft to something smaller, and then the compression won't have to be as high. I was really looking for the engine to run in the upper 6's which would put the engine running upper 10's in the 1/4. Had it not had the problem I believe that the next time out with more tuning it would have gone that fast. From the start to where I finished on the first day was 3 to 4 tenths faster, but not where it should have been. But I just ran out ot time for tuning.

Would I do this combo again, yep. It's a very powerful combo. And it will be again. The nice part about this is it can be vary streetable with less compression, and this is just a remachining of the piston tops. A smaller cam and .060 off the top of the pistons and you would be around 10.5:1.

Oh the 60 ft. times were in the mid 1.50's, they varied from 1.54 to 1.58. I just figured the HP on the brakeout run, it made 465 HP at the FW. 371 to the tires. And there was more in it.
 
So Bobby, do you reckon it was -

Too lean?
Too much timing?
Pistons too thin?
or something else?
 
Mal,
The air changed drastically, and the altitude dropped almost 1,000 feet. The day started at near 100* and when the engine went away it was 20* or more cooler, let alone the humidity went from 52% to 88% and air pressure went up .2. What this means is that the air was getting alot better and the need for more fuel was warrented, but I didn't have the time between rounds to make the corrections. Had the air not moved so much so fast everything would have been fine. I've ran into this a few years back and it did the same thing. It's just one of those times when theres nothing that you can do except hope for the best and go. Could it have been prevented, yes I guess it could have, had I had more data on this engine. But the engine was new and not yet settled, so I gave it what it wanted, I made 6 changes in 4 passes. Between chassis and fuel and timing. Everything was going the right direction until the air changed. So I guess you could say it was my fault for getting too greedy to fast, and wanting the engine to do the best that it could on day 1.

What I should have done in hind sight is, just went to test and tune and not raced. But I had alot of confidence in myself and the engine. And in the end I stubbed my toe. Hey thats how you live and learn. Now I won't see the air do that again for another couple of years. As it does it about every 5 years or so, where the air changes quickly at night. It'll more than likely get me again then, as you tend to get into a comfort zone. And you never know when it's going to happen.
 
Those were impressive runs for the first time out. It's to bad the engine ate itself up. Air can be a tricky thing when you start that hot. It would be almost like turning NOS on with no extra fuel. Makes silly putty pretty quick. I would love to see what a pump gas version of this engine would do.

Jack
 
Jack,
After talking to my transmission guy HT and Kenny Ford my converter guy they both said that the transmission and the converter should be OK. Kenny said that the worst that could happen is it would have stripped the input spline out of the converter hub. They both said that if the transmission would pull or move the car that it would be OK. Hey thats what I have these guys for, they really know there stuff when it comes to transmissions and converters. Anyway now that I know that I'm planning on staying with the 344 engine, instead of going to the big block.

This is the way that I'm going to redo the engine, so hopefully I won't have this happen again. It's going to be more on the street side, but with a bigger cam. I found pistons that I'm going to remachine but will only yeild 10.7:1 when machined. Then I'm going to use a comp cams 290-A, which is the same grind in the 322. It has .540 lift and 255 @ .050, what this will do is allow me to build cylinder pressure and run a lesser comp piston. Thus giving me more V to P clearence and maybe not have to valve relief the piston but .100 max. If that. It actually showed more TQ and a bit less HP. I'll lose about 60 HP but the TQ gains about 10 ft. lbs., but hey thats not a bad trade off considering that the compression will be 10.7 verses 14.96, and the duration will be 255 @ .050 verses 275/272 @ .050. Either way I'm still looking for 6 second passes or 10's in the 1/4. The nice thing is I already have a tuneup for this cam and head, and intake combo. With lots of data.

Anyway thats the direction that I'm going to be going. Hopefully I'll have it back together in the next few weeks. Also too the weather won't be changing that much as it will be cooler and the wild swings of temperture won't happen.
 
Looking forward to when you head out an give it another crack again!
 
Right now I'm in the middle of a engine for 72Scamp_Swinger. I'll hopefully have it finished by the weekend, then I have 5 sets of heads or so comming from Wedge Performance from Baton Rouge, LA. in a few weeks. So maybe in the mean time I'll get the chance to get back to it. I havent even messed with since it had the melt down. Maybe I'll get the chance to get the heads off this week. It only takes 30-40 mins. to take it apart.
 
Well, I took it apart today and #2 is missing a piston completely. I found a piece of the piston pin reenforcement in the intake runner of #4, a part of the top or second ring in #8 cylinder. And numerous parts of the piston in each of the other cylinders, and behind many of the valves. Needless to say that all the pistons will have to be replaced as they all have damage to them, from parts flying around. I'll have to replace some bent valves too, as there is parts of the piston behind them to. The worst of the damage is to the head as it will need a seat and a sleeve in the cylinder as it has a couple of good scar's.

But with some time and a few parts, and it will be ready to go back. I guess as blowups go this one was vary forgiving, as it could have been much, much worse. And especially at RPM's. It could have been lean but it's hard to tell when there isn't any burn pattern on the pistons. Everything is as clean as when assembled, other than piston parts and debris.
 
Well it's been a while since I saw a post from you How are you doing ? any news on the 349s you built for your customers ? ie build variances , dyno sheets , track times etc... , I'm still looking at going this route with my 318 and now that I'm on layoff I am cleaning out the garage to make room for a little work space and getting ready to start getting her out of the car and stripping her down . Hope to here back soon thanks -Chris
 
Chris,
Funny you should ask as I just today put it back in and it's up and running. The other guys that want one are still getting $$$$ together, parts aren't cheap as everyone knows. But anyway I'm going to the track track this Sunday, so I'll have some better results hopefully, as long as parts breakage doesn't happen again. But as of right now things are GOOD. I know that I'll have to do some tuning but looking for some very good numbers, as I have a base line from the old engine and tuneup.

Thanks for asking
 
Funny how that works eh!lol glad to here your ready to give her again , what changes did you make? I know you were talking about dropping the compression down to something that might run on high-test pump gas , I was hoping to hear about some other combos but I know as well as anybody about the price of parts and labour I got laid off a month ago and am just now expecting my first pogey { sorry a Canadian term for unemployment } cheque this week , lucky for me I was prepared for it to happen months ago and have a little reserve built up but it's still hard to tap into it knowing it could very well be 6 months or more before things pick up enough around here for my union number to come up . Enough about that crap forward ho we go I'm still on board for a 349 or slightly larger since I was told my block was 30 over when I bought the car I may have to go up a few piston sizes what is a 40/60 over build anyway ?
 
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