Thread: newbie help building engine

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TJB is a 73, 74, 75, and 79 350 cubic inch TRUCK motor with a single 4bbl and manual
trans. It is also the code for a 92 305 engine from a truck with TBI

Is there any other ways of knowing without tearing anything apart?

sbc retro roller kit .spring .seal. locks. retainers. cam. lifters. timming set. under $900. have to call but it was under $850 .then buy set of flat top cast piston $45. ring $20.bearing set $60. oil pump$20 gasket set $30 freeze plug kit $7.00 if bores are not bad then a hone and go with the flat tops . same with crank check size and polish and re bearing it . may need machine work no cheap way out. heads will need work block should be hot tanked and bored .if you do not want the roller cam then use a E903K ELGIN CAM KIT hyd flat lifter kit is the 350Hp chevy cam will run good and sound good

If you put that fosdick thumpr cam in the motor without raising the static compression ratio, you're gonna end up with a turd that won't pull the hat off your head. It'll lope, but that's all it'll do. With a static compression ratio of ~8:1 and a cam that closes the intake valve at 35.5 degrees ABDC @0.050" tappet lift, you will end up with a dynamic compression ratio of 7.05:1, leaving a full point and a half on the table.
Lope normally comes as a side effect after you choose the proper cam timing to work with the static compression ratio of the motor. You guys that want to start with lope, no matter how the cam affects the rest of the motor, deserve what you get. If I were doing it, I'd raise the SCR to mid 9's. Either that or install the proper cam for the SCR you have now. Maximum intake valve duration 195 degrees @0.050" tappet lift......NO LOPE......You don't have enough SCR to support lope and a stout motor at the same time, it's one or the other.

One of the ways to raise the compression would be different heads right?

Kind of gets back to what I was saying in the first place.You should face the fact how old of a engine your starting with<because it is a matter of fact>,it's current condition,the recommendations Pat has made combined with Tech's post.
To answer your question directly,yes a head swap can raise the compression ratio,but all for not if the rest is worn like a engine that old would likely be.

Originally Posted by 1gary

Kind of gets back to what I was saying in the first place.You should face the fact how old of a engine your starting with<because it is a matter of fact>,it's current condition,the recommendations Pat has made combined with Tech's post.
To answer your question directly,yes a head swap can raise the compression ratio,but all for not if the rest is worn like a engine that old would likely be.

yes and thats is were the flat top cast pistons can come in to play with what . decking the block will help and many sbc have very bad deck s for finish older sbc not bad newer ones can be bad . that is why i really do not care to post any thing any more anywere. i do not build engine for sound or buy smaller CR chamber head just to put bigger cams in for more sound . for me it,s the parts all working together to give the best output at the RPM range were the engine will see use. now i must go warm up my shop to work on some engines built for power

C4110 C 285 - K08-07tjb this is what i found on the front of the block.

Gotcha. Perhaps this may be more than what i was planning to do. Taking everyones advice i've learned alot about cams and compression

I'd go so far as to say a 51 chev pickup with a 350 v=8 was rad rod enough----

I think thats the way its starting to look jerry

Mike if and I'm not speaking for anyone else,but if you came up with say $1,500,it might get you closer to what you want and would work ok.

Tell you what,talk to Pat further.Ask him if you went to a flat tappet hydro cam,would that amount of money allow you to freshen up the bottom end,cast flat top pistons,and get a better set of heads.

Thing is your grand is certainly good seed money and might put you on your way to a nice cruise engine.

Your grand will cover the machine work. Parts are additional.
Check main bearing bores for being round and parallel. Correct as necessary.
Mount block on the main saddles and cut the decks to the required block deck height for the stack of parts you will use, so that you can use the proper head gasket and arrive at the proper squish (0.035" to 0.045").
Bore and hone with torque plate to the proper diameter for the piston and piston type used, using the proper grit number for the style and material of piston rings to be used.
If planning flat tappet lifters, finalize lifter bore diameter at lifter diameter plus 0.0015" clearance so that lifter can spin properly in its bore.
If necessary, machine intake manifold surfaces to be parallel with cylinder head intake port side. If these ports cannot seal properly due to non-parallelism in the X and Y axes, the motor could have an internal vacuum leak that you will never find. With the intake valve open and the piston ascending in the bore, the piston can draw in oily vapors from the crankcase and cause the motor to be an oil burner and could also cause oil-fouled spark plugs.

most of the small bore head gasket have gone away so i do not go by piston bore size but fire ring size used on the job for size of deck plate . like BBC 396/402 4.090/4.125 bbc and sbc 3.875 283 . hard to find smaller head gasket end up using a bigger fire ring gasket so my BBC deck plates are 4.400 and then up to 4.600 then 4.625 bore so 4.635. the one for 1/2 deck studs for 4.600 bores so its 4.635 sbc 4.125 . sbf 4.165. far has lifter bores on a worn 100.000 mile engine yes they should be checked . but not from to small for bore.i never seen it. but seen them worn out . GM and others did use over size lifters .hard to find . one has never cross my path but there out there. many time its a burr in the lifter bore. not from a small bore .a simple check and a BRM hone will fix this. i do the lifter bore in honing machine after honing the bores. has for new block with race roller lifters bores are fitted for the lifter this is done with my sunnen p190 and a mandrel with diamond adrasive all work getting varified by using sunnen /mitutoyo /sharrett .fowler .kine.ABS .goodson .magnaflux others and tooling along with many jobs i could cover two pages of work threw out the build along with many other $$$ tools . the just machine work would be under $ 1000. BUT it would have to do with what the engine neededs to be done to it? a tru -deck with BHJ and bore with deck plates is $310 that the least i would do to the block. less the line bore is hurt then about 150 to 170 for that job. but that is what it cost for me to work on your engine. this may cost you more or less were you live . my shop is full of work so i not looking i am just saying what the cost is around here and some jobs i get more for then other shops do it for

Originally Posted by rspears

Bull! I agree 100% with Dave. You want to change out your cam and lifters, not build a race engine, or plan to build one later. That fine article from the Crankshaft Coalition, (written with a lot of input from TechInspector1 who sometimes graces us with his input here and who knows more about cams and integrating them into any engine) provides excellent guidelines on choosing the right cam based on the engine you have. Don't let anyone belittle you about what you want to do or the amount you have budgeted. You don't need any master plan if all you want to do is swap a cam. You can use the information you have to get a modest HP increase, and also pick up a modest lope that will let everyone know you're not running a stock engine. Forget about horsepower goals, torque goals, and all the other high performance, high efficiency falderal. Dave very accurately pointed out that you're going to need to go into the engine and do some machine work to worry about such things, so pick out a cam that's not too wild for your compression ratio, have a ball, and ignore anyone who tells you you're wrong to buy a cam and lifters for an otherwise stock engine. Been done that way for many, many years, and you can always go bigger down the road, when you have the need, and maybe the extra bucks to play bigger. Have fun!!

I am in total agreement with Pat and Tech as I stated before they posted.All too often a question about a "simple cam swap" involves more than just slamming a cam in.It is irresponsible to advise old school in cases of a engine that is say 30 yrs old.The risks involved with doing that does not out wt the benefits.It is just a simple matter of applying common sense that has nothing at all to do with a one of a kind race engine.And to advise a O/P of those facts is not to discourage him in anyway.It is for certain to protect him for the money he is investing.

This stems from the 40+ yrs I have been involved with hot rods and that is combined with a background in mechanics as a engine tester at the Chevy engine plant and yrs of working as a wrench in repair shops.My professional opinion.

I think there is a compromise between the grand he says he is willing to spend and not much more for a economic rebuild.I agree that a grand might only cover the costs of the machine work needed depending on what is found once the engine is checked out,but with a sensible rebuild of cast pistons,flat tappet cam and kit,and good set of heads maybe later down the road is the best way for him to go.That is far,far,away from a race only engine.