Inliners International Forums General Discussion Engines Newbie: Chevy 250 help

Ive got a 79 chevrolet nova with a 250. Im saving money to mod the engine. Here are my questions:

-What are good places to purchase parts for my engine?

-What kind of setups do you guys have on your 250's and what type of performance do you have.

-Does anyone know any books or websites to help me learn a little more about the 250 (Im only 16). Im a grease monkey in progress.

thanks in advance.

A book entitled Chevrolet Inline Six-Cylinder Power Manual by Leo Santucci is a wonderful source of tons of information, good luck!! As I remember, it might even be available thru Wal Mart.

Genocide
Welcome to the inliners World. Well One good site to start at and stay Is right here. You can also Order that Power manual right from our Club and I do believe you can oder it right here on line from our club stuff link is on the left. Now Big #1 Question is what are your Plains Fo rthis Build? Street,HOT street,Race? This will help Us give you some better Ideas.
Hope this helps.}[oooooo]

Ps as to what I was running Before Building a Fresh motor after 17yrs well it was a 250 block .030 over 12-1 307 pop up pistons Milled to clear the 586-607 lift cam My own custom Built 3x4(3 450 holleys) tunnle ram Intake m20 4speed 60s style Hurst inline Shifter. rear wheel dynoed at just over 300hp putting V8thing to shame

Thanks WTBQ and Twisted.

Im gonna take a look into that book sounds like what ive been looking for.

Plans for this build... Hot street would probably be the term to use out of the three givin. I want it to have more juice than your average car but I also dont want to guzzle 1 mile to the gallon. Oh and I want it to sound like a V8 lol. I want heads to turn lol.

Just if you guys are interested in my car. It is a 1979 Chevrolet nova. Obviously it has a GM 250. The interior has been sent out to my upholterer/my cousin and I have rust proofed the entire floor. Ill get up some pictures if anyone is interested. thanks in advance.

Here are some more of my questions:

-What type of intakes to you guys recommend?
- 3 2bbl
- 1 4bbl

-What type of carbs would you reccomend?

-What type of exhaust would you guys recommend?

Thats all for now thanks in advance

What to run will depend on what your plans are for the car. It all has to work together so be realistic about how the car will be used. A big lopey cam with all sorts of compression added sounds wonderful and certainly has bragging rights but if you plan to drive the car you need to skip all the drag strip parts or you won't enjoy it. Putting big parts into and onto a small engine doesn't always work. On the other hand if it will be mostly a legitimate drag car then milder street performance parts won't make you very happy.

Here is what I am running in my 250. A .030" overbore to clean it up, a ton of head work including larger intake valves and semi serious port job. Compression is 9.8 to 1, Offy 4 bbl manifold with a 500cfm Edelbrock carb, Clifford street rod headers into 2 inch dual pipes and mufflers. The engine is fully balanced and clearanced and runs a fully upgraded HEI and an electric fuel pump. Comp 260H cam and spring kit and Crane roller rockers. Behind it is a 15# flywheel and M20 Muncie 4 speed turning back to 3.36 gears in the rear.

This thing runs excellent in traffic and on the highway and can dust off some very surprised small block V8 drivers. The engine has no bad habits and sips down gas at that rate of just under 21 mpg on the highway at 70 mph. Its been in my 37 Chevy for 2 summers now and has recently turned 10K miles.

Get a copy of Leo Santucci's book and read it until the print is worn off the pages. His recommendations are well thought out and will save you time and frustration in the long run.

Take your time and do your homework. You'll be glad when you see the end results.

Mike

My idea for this engine as far as performance is definetly not drag racing. I dont have that kind of money, unfortunatly. Really, I want to add performance with out compensating fuel economy. I would mind burning a couple Mustang 5.slows at my highschool. Im not going to be doing the engine work until this summer so I figured I should plan ahead.

37 chevy... **** that is an old car. I thought mine was old lol.

thx

I believe the 79 Nova originally had the intake manifold integral (part of) the cylinder head. If where you live does not have smog/emission checks it will probably be worthwhile to find a pre-1975 head with the separate intake manifold. The integrals tend to crack and have very limited performance potential. It might be worthwhile to find a complete earlier 250 to rebuild as that way you can take your time with the rebuild and still keep the car on the road.

Yes -- get rid of that integral head. As far as a mild performance build goes there are lots of ways to do it without breaking the bank. For example you can score a small quadrajet, or a Rochester 4GC, off ebay and avoid spending a ton of money on an Edlebrock. Get the older -nonintegral- head, and anybody with minimal fabrication skills and some welding ability can split your exaust manifold and modify your intake to take a four barrel, saving you around $500 bucks. The list goes on and on, but basically with a mild cam, bumped up compression ratio, mild port work, bigger exhaust valves, a good working 4 barrel, and dual exhaust, running into a T5 tranny and a set of 4.11 gears with powertrax differential locker you can make your pony car buddies look like idiots in any 1/8 or 1/4 mile runs. The down side is 4.11 gears do not make for good gas milage; I get around 14 with my LWB 70 Chev pickup.

Now, about this business of sounding like a V8, you have evidently never heard a hot inline 6. They sound way cooler than a V8. A hot 250 running through a set of glass packs at 4500 rpm sounds like something is coming to kill you and eat your family!

It's great to see a guy your age taking an interest in old school motors. Remember 3 things:
1) God hates a coward
2) Wrecking yards are full of 250 chevies so parts are plentiful and cheap.
3) If you have a cutting torch, a welder, and a sufficient supply of coffee, nothing is impossible!

Above all have Fun, and keep your rod between the ditches with the shiny side up!
Boo

Just reading the last post and have to say that its not true that most wrecking yards have 250s anymore the price of scrap steel is too high to keep them sitting around for 20 years like they once did.

I would go by them all up left and right if I were you for $50.00 a piece or less becasue you can always say to the guy look at the metal place you will only get $20 or $30 for that engine.

Its nice to hear some young folks are interested in inline 6s but lets treat them like lost sheep and look after them and give them a good home before they go get crushed or sent to Mexico.

Thanks for your input. Please dont think that i have heard this stuff before because i havent.

Unfortunatly I dont really have access yo a welder nor do I have the skills required for welding. Though I am trying to find a job at a local body shop. I will look into the non intergral head see what i can dig up on ebay. Just for a quick reference what is a good price for a Pre 75 head and also what is a good price for a quadrajet?

thanks in advance

You have a great car to run a 250 in, so just patiently work through the learning curve, and you will end up with a really cool hot rod.

I wouldn't recomend fooling with ebay to much. Most stuff sells for way more than it's worth. Scouring your local wrecking yards and swap meets is a better idea. Along the way you'll meet good people and build lasting and valuable freindships.

You shouldn't pay more than $75 for a head because all you want is a rebuildable core. As for a q-jet, you should be able to find a good one for under $50. I know guys that have buckets full. The thing to decide is how wild are you going to go with your build. The q-jet came in several sizes, and you do not need a 650 or 750 cfm carb for a mildly built 250. For example, the engine I described above works good with around 400 cfm. That leaves a bunch of options; a pair of Carter YF carbs, a 425 cfm Rochester 4GC off an old small block, a Holley 390, a Pair of Holley/Webers, et. We could easily add to this list.

Get Santucci's book, plan your work, and then patiently work your plan.

boo

Thanks for the information. Just for everyones information I do not plan on starting any type of engine modification for a while now. I am saving up to get the body taken care of. Thats why im asking questions out my a$$

The plan while the body is getting done is to the motor pulled. Then ill be able to do what I need to do to the engine while the body gets finished up. Right now, Im just asking questions to help me figure out what direction I should be going in when it does come time to mod the engine. So thank you all for you help and not getting mad at me.

Now that you bring up the sizes for the CFM is it possible to over "Power" and engine with a carb that is too big? This may be a stupid question but that would mean im a stupid person....

Too large a carb won't overpower the engine, it just slows the velocity of the air and causes the carb to be inefficient, lots of stumbling and no low end torque.

The Q jet off a v6 is a good match for our 250s And most 250 heads around me in the bone yards go for about 150.oo 300.oo for the whole motor.

Ps there is no such thing as a stupid Question If You don't know You just don't know. And You'll never know if you never ask.
LOL LOL besides If their realy was a thing as a stupid Question I'm sure we could find some stupid answers LOL LOL
but hope this helps }[oooooo]

Hmm interesting bout the carbs i figured there wouldnt really be a difference but i guess that would just make it to easy.

Here is another question I had: Is 1 4bbl better than 3 2bbls?

What type of intakes do you guys recommend for a 4 barrel set up? I guess intended use of the engine would be involved again so I would describe it as a daily driver with a$$.

I think this weekend I might go to a local junk yard (im right out side philly and there are literally 20+ junkyards withing 20 minutes) and see if i can locate the heads you guys are talking about.

Any tips for finding a head that is a prime candidate for a rebuild? If it has a 4bbl intake mounted on I assume it would be easiest to just grab the whole thing, including the carb? This will be my second time to a junkyard and the first for my own purposes.

Well thanks again for the help.

For a newbie/novice to building and tuning engines, and for a mildly built or stock street six cylinder I say go with a small (very small) 4 barrel or a 2 barrel. For best performance keep the 4 barrel at around 400 cfms and the 2 barrel no more than 350 cfms.

Twin one or two barrels would burn more efficiently I'm sure, as the carbs are set closer to the ends of the engine. And you'd probably get better throttle response and overall performance from 2 two barrels versus a single 4 barrel. But for maintenance and tuning purposes the small 4 barrel would be your best bet.

Either the Clifford or Offenhauser 4 barrel intakes will work fine. Unless you make your own they're your only two bolt-on choices for a street engine. You'll have to adapt water heat to the Offenhauser and the older Clifford intakes that don't have the water jacket built in. Unless you've done some extensive head work and have beefed up the cam I recommend the Offy, as the Clifford has larger intake runners for better upper RPM performance. The Offy should work best for low-mid RPM torque & HP. And from what I've seen over the last year or so the Offy generally goes for about $100 or so less on Ebay than the water heated Clifford 4 barrel intake.

-magic mike-

Genocide,I'll tell you what.Since you live near Philly and I have a 1968 250 head sitting on my bench collecting dust, I'll email you my phone number or email me,and if you can make it over to South Jersey, it's yours for FREE. It's good head, but should probably be checked out by a machine shop. It had about 80,000 miles on it when I wrecked my truck.

Yea, I was talking with my boss who is a mechanic and he was telling me that if you have the on carb in the middle, the outer cylinders will run lean.

Thanks catdog Ill have to talk to my dad about making the trek down to southern NJ to pick up that 250 head. If I cant make it down would you be interested in shipping it, if i covered the shipping costs of course. thx ill let u know wat my ol'man said

Here is another question I have about the choice of heads: Is there any year head that had its intake ports on one side and exhaust on the other?

If so what years was it produced?

Are they worth more than other production heads?

Thanks again for the help. Im sure ill have more q's by the end of the night.

Chevy doesn't have a cross flow head for our L6s Unless it has been a V8 head cut up and rewelded. But the blocks have to have mods made to them as well as You have to make your own side lifter cover. Hope this helps }[oooooo]

This is a great thread. Keep up the good work guys!
Boo

Gonocide, Get the book referenced in this thrad "Chevrolet 6 Cyl. Power Manuel". I got my copy last week. It has a TON of information in it!

Yea it seems that book is the key to all knowledge lol. well thx ill have more questions soon enough.

Update... I have decided to do the body work myself. I dont trust myself with a spray gun so i wont do the painting but im going to strip my car down by hand. Ill get some pics of my nova up soon so that way u guys can see wat im working with. thx for all the help.

Genocide,
Thanks for the question and gathering some great answers your making it easier for me. I have my 250 out, ready to be rebuilt and I was looking for ways to add power. Just two questions for all;
Will I notice a big difference in power if I add a 4 barrel, intake, headers and keep the internals stock?
Will changing any of the internals as well make a big enough difference?
I am driving a 69 chevy truck, adding a T5 trans and the rear end is a stock posi-track, but I don't know the ratio.
Looking for ideas before the engine is torn down snd how much it will cost.

And it will be a daily driver that will be pulling a boat, hopefully a lot!

while you are thinkin about carburetion, 9or anything else) remember this acronym:KISS. it stand for Keep It Simple, Stupid....if you can do something several ways, choose the simplest way. That comes to carburtors..youll find one 4 bbl easier to deal with than 3 2bbls. But then, 2 2bbls looks a lot cooler than one 4 bbl, thats for sure. Youmay well have to.....how often & what kind of smog checks you gotta deal with where you live? To pass, not only are the emissions havin to be within spec, all the stupid crap they hang on the engines has to be there too. out here its every 2 years, so Ill have to yank the manifolds, hang the stock crap back on it, get it tested, then put all the good stuff back on. What you may want to do is pick up that head the fella offered, do all your mods etc, but get the car smogged before you actually do anything to make it run better. KEEP THE OLD HEAD & parts! keep all the stock crap- youll need to swap everything back for the test in the future. **** Democrats. Consider it practice. And like the guy said, rear gears that get you down the road drag style takes a toll on your mileage, while tall gears that let the engine RPM stay low at highway speeds slow your out of the hole acelleration....keep all us old farts posted, you picked up a couple dozen instant uncles....mutt, Ca.

well in pa. you can get a reconstructed title and be exempet from the emissons test.or get and older truck or car. i am putting my 72 c10 back on the road. it is all just a money making scam.