what all do i need to do/buy to take my 305 to a 335 and about how much would something like this cost? i'm just curious, i tried to search the forums for similar info but the page that kept coming up just said page cannot be found or something like that. thanks.

This has been brought up many times on this site. Alot more as of lately. I looked into doing this myself.

The stroker kit can be found from http://www.enginekits.com they are the only company that sells a kit for this that I know of. Its about $599.99 I think. At any rate you would then have to get the machine work done on the engine and what not. If you assemlbed the whole thing yourself you would save some coin, but if you have an engine builder setup everything the cost goes up. I have found that the whole thing will cost around $1500-1700 give or take.

What are your goals for this car? You may find that building a 350 would suit your needs better than the 335 would. In which case you won't spend a whole lot more if any on a 350 setup.

For N/A power you can spend a little more and get a 350 crate engine that puts down more to the wheels than the 335 would. That is what I am going to do most likely.

the only thing i hear is sometimes, blowers like les cubes, but that's gonna cost ya!

I don't know about the less cubes thing. But Willies setup is FAST. And it uses a blown 305.

the website listed for the 335 stroker kit says that can see gains of around 95hp carb, 115hp with fi... so i'd see 115hp gain with a TBI setup? i plan on puttin on a 4barrel type tbi unit and my friend has a 471supercharger sitting at his garage back home, would a setup like this work?

I guess, but why would you use TBI, unless you have it already.. I'd try to go w/ some type of FI,...and DFI,...and i don't think TBI will see the gains of a carb or FI, but hen again, i have NO experience w/ that. just my 02

my car is a 305tbi setup sadly enough, how difficult AND expensive would swapping to another setup cost? and what would be the best for the money setup to switch too?

well, i'm just afraid of TBI, because i knowit's not great, and you'd hav to upgrade it,....so why spend money on a crappy system to begin with. you probably won't be happy w/ it. I'm not trying to say it's horrible, but you could get used TPI setup, complete, really cheap. The swap isn't simple, if that's what you want, but you can do it,...it'll just take a lot of time. I guess if you need the car right away, stay w/ what you have, and just upgrade the TB and inj. Like i said theough, it's like throwing money away. Anyway, I think alot of guys use the LT1 intakes now, but that's probably more involved than going TPI. Depending on you willingness to learn and do, the TPI swap really isn't that bad. To save money and agrivation, get a MAF (mass air) tpi setup usually found on 87-88 cars. You can peobably get a complete stock system w/ wire harness cpu and hardware for under $500. Or you can piece it toghther cheaper. Even if it's from a 305, the only differnceds are the TB size, inj size and egr valve. u can get 350 inj cheap, used, adn a 350 tb real cheap. you wouldn't even need the 350 tb right away. hope this helps

I would use either after market DFI or modified TPI. I can't stand TBI. From the things I have read about it and I have worked on a vehicle equipped with it once.

i'm trying to keep my costs low low cause i'm just trying to tweak out my cheapy 305, i plan on buying another thirdgen sometime in the near future and plan on spening the big money on that one and keeping this one as my beater/daily driver type. lol. how much is the DFI setup run, i heard like... $2000+... that sounds right?

And another sucker is about to get parted from his money by that "95 HP" bull droppings.... notice that the "95 HP" claim is for some heads, a cam, an intake, exhaust and carb, and oh by the way, the 30 cubes. Nobody in his right mind would actually fall for a line that says that each of the cubes in the motor right now puts out ¾ HP on a good day, but those 30 additional ones put out more than 3 apiece.

Get a "bore kit" instead. It's cheaper, requires no special machine work or unusual pistons or grinding on the block or special smal-base-circle cams or anything; you can even re-use your existing crank and rods. It costs anywhere from $50 to $100 in most locales, and adds 45 cu in to your 305. Much better $$$$/HP ratio.

"Bore Kit" , That's funny 350c.i. power baby !!

But if you still want to go with the 335 I can save you some money.....








You just give me 1/2 your money I'll kick you in the nuts as hard as I can and we'll both go home in a better mood then if you would have built the 335 (I'll have more money in my pocket and so will you and you won't have a peice of crap engine!)


Later, Garrett

I went from 155 HP net rating at the flywheel to 250 HP at the wheels (calculated from 1/4 mile performance). Without doing anything to the bore/stroke of this lowly '86 LG4.

It cost me a bit more than that 335 stroker kit, but then, as RB says, it took a lot more than that 335 stroker kit to get a 95 HP boost.

TBI heads? No stroker kit (or "bore kit", for that matter), is going to result in a 95 HP increase. Just isn't going to happen.

Step #1 is to dump the TBI swirl-port heads.

Step #2 is dump the TBI exhaust - from heads to rear bumper.

Step #3 is improve the cam.

Step #4 is to tune/tweak it so these improvements will produce power improvements.

bore kit... where would i get one of these and what all is included??

ok, i already have a custom flowmaster exhaust, what heads would u recommend swapping to looking at best for the money, same for the cam, what cam would u recommend?? i work on aviation electronics (radar, missile guidance systems, etc), not mechanics, so this is all new to me, but i pick things up quickly

I was being "funny" (I know I know, don't quit my day job....)

You get one at a junkyard. All that it includes is one big piece of cast iron, and 5 smaller pieces that bolt onto the bottom of it. It's nothing more or less than a junk 350 naked block.

lol ic ic.

Another source for the stroker kit is Powerhouse at (661)861-0617. Their kit is complete with a new crank, pistons, rings, bearings, balancer, flexplate, connecting rods and gaskets for about 6 bills. Don't forget that Vortec heads fit on 305's. It is the absolute best modification you can do for the money.

outstanding. do they happen to have a website that you know of?

The above-mentioned enginekits.com link is Powerhouse.

I'd say a stroked 305 w/Vortec heads is far from the best modification you can do for the money. Very, very far, on both counts.

305 + $100 and no special parts or machine work = 350
305 + $600 for special crank and pistons = 335

I can't figure out which one is the better value. Somebody step in and help me here, I'm just really struggling with this. The 2nd option looks mighty attractive since I get to use this "paid for" block. I think I'd better go consult my financial adviser, maybe my astrologer and personal psychic too, to get their help on figuring this one out.

how do you make a 305 to a 350 with $100??

Buy a junk 350 block

You're buying pistons anyway when you're doing a rebuild, and it's revenue-neutral whether you get 350 or 305 ones, maybe even more favorable to buy 350 ones. There's alot more 350 choices than there are for 305 though, by a long shot.

id definetely go with the 350 and lose that tbi stuff. yeah u can build up the 305, but y make things harder on yourself?

as for the type of intake, id go with a carb setup, your engine doesnt need some plastic piece with needles and wires in it telling how much fuel to give, i say let the carb dump the fuel and air in and let the cylinders fight for it!:rockon:

just my 2 cents

Listen, it's like this...

Stroker kits ARE great kits IF... like for example, you have a motor that's not easily replaced. Or.. if for example, you wanted to keep your car stock, well.. numbers matching. You could buy a crank kit... put out a few more cubic inches and give yourself some more power. This way, it's STILL the same original block that came with the motor, and you have more power.

to be totally honest, I don't think you'll see 95 horsepower. I'm just going to figure.. say your motor has.. what, 195-200 horsepower stock? That's a 305. Going to 30 more cubic inches logically would only give you about 20 horsepower.

However, you have to figure that if you're going to spend that money, you're probably going to get slightly better pieces, so I'll go out on a limb and suggest that you'll probably get somewhere in the neighborhood of about 30 horsepower.

The difference between your previous motor, and having the new stroker kit installed would be like if you took the stock motor, and installed a high performance cam-shaft.

HOWEVER... if you have NO plans of keeping this car factory stock, then I'd suggest getting yourself a used 350 somewhere. I would still spend the case on rebuilding it. I would never put someone else's used motor in any of my cars.

If you do go with the stroker kit, you should also just throw in a high performance camshaft.

With a high lift cam, roller rocker arms from Competition Cams, and that 335 stroker kit.. you're likely to see (realistically) about 60-70 horsepower. If you take it a little further and spend $100 bucks having your heads ported and polished.. you could squeeze another 8-9 horsepower out of it.

I purchased a stroker kit a while back. It too only increased my motor's capacity by about 30 cubic inches. But this was on my 1987 Pontiac Fiero SE / V6. Stock, it came with a 2.8 V6/60. I purchased one of those aftermarket crank kits. The kit brings the total displacement up to a 3.1 liter using a 3.1 crank and rods. I then purchased hypertecitc lightweight aluminum pistons, chrome moly rings, roller rockers, a 2030 Crane Cam, port and polish of the plenum, intake, runners, heads. I got headers, free flow exhaust, 19 pound fuel injectors, you name it. The new pistons were also .040 overbore so I ended up with a 3.2 liter. It's not running yet.. heeh, bad fuel pump, but it should be putting out around 195-200 horsepower.... that's a drastic improvement over the 140 it previously put out. However... this is in a 2700 pound car.

What I mean is the Vortec heads are still best bang for the buck regardless of it's a 350 or 305. I would be willing to bet that the Vortecs would give more power than the stroker kit will, if you were forced to choose one over the other. I tend to agree that the 350 would be a better choice if emissions and fuel mileage are not a concern.

And I would argue they are not, especially on a 305.

But, that's another thread (or, should say, has been many, many other threads).

Back to the topic: If you want more performance out of a 305, there are good ways to achieve it without the stroker kit. Bang/buck, the stroker doesn't do it.

If you want more performance, period, get a 350. If you want more performance out of a 350, a stroker kit is a good way to achieve that. In fact, you can buy a 350 block, stroker kit, do all the required machining, and still pay less than you would stroking a 305.

If you think 335's will out-run 383's, then there's no point continuing this conversation.

There's a rule I've always live by....

A good motor does NOT make a good car, but a good car LOVES a good motor.

91 camaro rs w/t-tops, 5sp, open element K&N 14X3, K&N filter top, dual flows, AR 89-92 camaro big block hood w/functional hood scoop and cowl induction

From those mods you have, you're on the right path.

Make the cowl hood FULLY functional if you haven't (seperate the air cleaner from the engine heat).

Get steeper gears (3.42 seems to be good for a street/strip F-body. 3.73's are pushing it especially with TBI).

Get a posi (either a locker or limited slip).

Get headers (as already mentioned).

Then (as five7kid said) get some good heads, and cam to match them, then an intake manifold to match both of those.

The sum is only equal to it's parts. Don't put a stroked 305 in an otherwise stock car and expect good things to happen. It won't.

If you visit the TBI board often, you should have seen A LOT of guys who build their cars (not motors) and are able to shave 1 to 1.5 seconds off they're ET, and they don't break one bolt loose on the intake manifold. THAT is what hot rodding is all about!!

How much do good heads for a 305 cost? How about the machine work?

Depends.

Heads - you can pick up a set of used 081 factory heads fairly cheap, maybe even free. If you do the porting work yourself, it's the cost of equipment and materials. Valve jobs vary by area and shop-to-shop. I just had my 396 heads done for $160, including cutting guides for positive seals (and the seals) and 3-angle valve job by a guy who knows performance (he won't do porting for customers, only his own stuff).

Otherwise, aftermarket heads are typically 350-type, meaning they need to be shaved to keep compression up. Only exception is Worlds, and they need porting help before you bolt them on. They'll run you about $700/pair w/valves & springs. Pro Lightings are slightly lower, don't know if they come clean enough to bolt on as-received, but would need to be shaved, anyway, since they are 350-style.

Again, don't forget about the Vortecs. They are about $450 and with a Vortec Performer RPM, your coming in right around $600. That is cheaper than the S/R Torquers and there is no comparison between the Vortecs and S/R Torquers. The stock 305 LG4 heads are junk, in my opinion, and not even worth considering. They are the reason most rodders hate 305's. They have poor chamber design and this has directly contributed to the fact that stock 305's are detonation prone. Coupled with the poor flow, your basically asking your 305 to breathe through a straw! Bolt on the Vortecs and you can play with timing without fear of detonation. I know the stock LG4 (305)heads come with .045" compressed head gaskets. You might be able to bolt on the Vortecs with a shim gasket by Felpro (Part # 1094) or Mr Gasket that comes in at .015" compressed and not have to mill them.

About everything you said about 305 heads applies to LO3 heads, but hardly any of it to LG4 heads. My '86 had steel shim head gaskets from the factory. Several people have ported 416's/081's (with 1.94/1.60 valves) to flow better than Vortecs out-of-the-box. If you plan on a cam upgrade, you'd better figure on spring upgrades to as-received Vortecs. Without EGR, you'll be fighting pinging with Vortecs, too (assuming you raise compression, and haven't plumbed exhaust up to the intake). Don't forget the need for self-aligning rockers. LG4 restriction is in the air cleaner, cam, and exhaust, not in their heads if ported.

I know it's possible to get good performance out of Vortec-style heads. But, almost without fail, Vortec-lovers look at their installation through rose-colored glasses, forgetting to mention certain details or just plain not telling the straight story.

I listed all of the faults with the Worlds (except center-bolt valve cover fitment - make sure you measure the gasket rail on your center-bolt valve covers, because the Worlds are narrower than some early factory centerbolt covers).

There, now I've listed all of their faults. You're still better off money-wise with Worlds or stock heads, if you're willing to do the port work yourself (took me a grand total of 10 hours, and this was my first porting/polishing attempt).

Well, we've succeeded in turning this from a 335 thread into a Vortec thread...

I don't know. Between the heads and the cam, and all the rest of the mess I can get a crate 350 that's TPI friendly for $2200. And a 383 for 3K. And I think it would be money better spent.

If you are open to going that route, I would certainly do it!!!!

There is no replacement for displacement. My plans are to do everything the way they should be done to get me to my goal of 12's. They don't have to be low 12's. Just in the 12's.

My plans are to get the 383. Then supercharge it. I should have the engine in a month or two. I will do everything I need to do to the car first before I install it. But you get the idea. I want to keep the cost reasonable. But I also want to get results. If it costs me 12-15K then so be it.

I am not going to argue your LG4 heads came with shim gaskets but the GM dealer in my area says the are LG4 heads are thin cast heads and does not recommend the shim gaskets. The new Felpro shim gasket (1094)say right on the cover "Not recommended for thin cast factory heads."

Anyway, Vortecs are good unmodified for lifts up to 465". The largest cam recommended by Crane for a LB9 305 TPI motor is the CRN 113931 which has a gross lift of 440" on the intake and .454" on the exhaust. No spring modification necessary. That recommendation comes right from Crane's Tech Line. It is the largest emissions legal cam they make for a 305 with other emissions legal modifications (ie. high performance cat back exhaust). I have run the exact cam in my truck for 4000 miles now with no problems with stock 062 Vortec heads.

As far as 416/081 ported heads out flowing Vortecs. You can certainly get them to out flow Vortecs but you can't match the chamber design. And thinking you can do a port job that outflows Vortecs without a Flowbench is pure stupidity. Go see the boys at Dyno Pro Inc. in Denver and run that crap past them. These guys make a living out of tuning the hottest cars in your area. Tell them you think the bathtub chamber designs of the '70's can duplicate the current generation of heads. Better yet, find me one crate motor out there that even uses 416/081 heads. Their design is not only outdated, there isn't a firm that would warranty those crack prone pieces of junk! Show me one company that sells performance heads that even uses the bathtub design. AFR, Edelbrock, Canfield, Brodix, Trickflow and not a single head in their line uses the old design.IF YOU ARE USING THE OLD BATHTUB CHAMBERED HEADS OF ANY YEAR, YOU ARE SELLING YOURSELF SHORT. Vortecs are the cheapest heads of this new design. They were deleloped from the LT1/LT4 design and have more than proven themselves in limited racing classes where factory heads must be used. Go check out the podium of any of these limited classes at Rocky Mountain National Speedway near you. You'll see for yourself. If I'm looking through rose colored glasses then you must certainly need glasses!

Calm down man...

five7kid is only saying that the Vortecs need a few other mods to them to be 'performance' ready like the World heads already are.

OK... you buy a new set for ~ $475. Pay a machine shop to have the guide bosses ground down to handle springs that will handle .540" of lift (What World's can handle). Buy the springs, retainers and keepers. Install screw in studs w/guidplates (come on World's). Mill them down to 58cc's for a 305 (like the World 305 Torquer heads), etc. etc...

For the same money spent (or maybe slightly more), you CAN have the Vortec heads, but then you have to buy a new intake manifold (Vortec specific for TBI) and buy the EGR adapter (if you have emissions tests).

Add that do the overall cost and the Vortecs start becoming expensive.

I'll personally vouch for that statement.

91 RS 350 vortec-tbi. Emmisions legal.
PS: And don't forget the vortec intake gaskets. I think I paid $28 for those. Ouch. There are other costs also, but I'm trying to forget those.

S-D

I hear you guys but most of the costs are going to be incured sometime in your upgrade process anyway. I realize that we're not all made of money and have to do things in stages. But you have to agree that most guys that upgrade to performance heads are 1) going to get a performance intake to match. In the case of a carbureted car, the Vortec dedicated manifold will be $50 more but in the case of the TPI, the Vortec base is actually cheaper. Scoggin-D's are $400 versus SuperRam at $537 with TPIS and others close to the same. 2) Going to upgrade to roller or at least roller tip rocker arms. There are no less than three brand new sets of Cat roller tip rocker arms on Ebay right now for a Buy It Now price of $95, these are self aligning and the same price as non self aligning. 3) Will have a rebuilt set of heads milled flat before installation. The cost of milling flat versus milling to gain compression is not that much more. Point is that the cost of Vortecs perceived hidden costs are because the commitment to use Vortecs forces you to make those modifications listed right away rather than in stages like other factory heads.

I will concede that gaskets are more expensive but that maybe because the Felpro gaskets that are for this application are the best made. And I have to tell you that most 305 owners are not going to have to make that guide/spring modification with the lifts that are recommended by cam manufacturers, particularly in TPI equipped cars driven on the street.

I realize I was harsh but I have had the good fortune of working with one of the premier head porters in my area and I can't stress enough about what an art head porting really is. I have watched him work on a set of head for hours looking for every bit of flow. All this measured with the latest flowbench technology. It is so dangerous to think that the common Joe with a Dremel tool and some dies is going to match the quality. And I can't tell you how many customers come in with heads that are junk from trying their own work without any knowledge of turbulence, short side flow, etc. Going in and hoggin' out a port and thinking your doing good without a working knowledge is just wrong.

my friend's uncle has a 383 stroker in his car pushing out 510hp, non supercharged, all natural, running 10's. the other thing is you better think about building a stronger tranny if you got the 700r4. no way one of them will take that kind of powervery long. 700r4 is a good tranny when it works, and when you don't have massive power, but you put power to it and forget it. my dad built a 305 in his truck once, witht he 700r4. it blew the seal out 3 times within MAYBE 6 months. to be running 12's you better definitely be thinking about gearing, if you're going to make all that HP, then you can go with the 3.73's for sure. i've got a stock LO3, it's not the quickest car but it can move. the worst thing about it is the gearing. it's got 2.73 gearing and it's going to be changed to 3.23, i'm getting headers, hooker cat back, lt1 cam, and a chip.. i'm hoping to run very low 15's maybe high 14's. my goal is to stick with an LT1. around here i need nothing massivly fast. all thats around here are cars that think their fast. first time i took my car around my block i didn't even have it on the road i had some ******* rev his engine at me in a bright orange acura then i ignored it kept going and he got on my *** so i stopped he came next to me and we both went and i beat him pretty damn bad, he got me off the line till i stopped spinning my tires which was when i hit 2nd. but all in all a 305 isn't that bad of an engine. if i had a choice it would definitely have a 350 over a 305, but i'm not complaining about a 305, not one bit. especially for my first car.

Do any of you have links or examples (Dyno results) for a LO3 with vortec heads a decent cam and tbi(I was thinking of using the tb adapter)
Also not sure about some intakes, Other than egr (not planning to use) what else do you HAVE to have to use tbi?

Any HELP would be appreciated

Here is one popular link: http://www.goingfaster.com/spo/carcraft325hp305.html

Don't mistake the 305 Vortec heads for the performance variety. Your looking for a 062 or 906 casting...or even better consider the ProAction Topline 906 castings. There is a set on the classifieds of this website as well as sets being sold on Ebay by Yoder Racing. These have an improved port design, thicker decks that can be milled to 58cc or less and are already set up for bigger cam lifts as well as screw in studs. I am probably stating the obvious but which ever Vortec head you choose, resist the temptation to go to a 2.02 valve. The larger valve will not fit your small 305 bore.

I am not familiar at all with TBI technology but this is probably one of the best links for any questions you might have on the subject. Surf around the website for their e-mail address.
http://www.turbocity.com/TBIPowerMain.htm

In this case, more IS more. don't bother with the 335 kit for a 305. The 305 has enough breathing problems as it is, no need to make it worse.

I would just get a 4" bore block and drop your 305's parts into it. You can probably get a decent block for $100 or less, and you will have 15-20 more cubes than the kit, depending on if you get a clean up bore done. And they are the good, lotsa hp making cubes, not the pull-your-house-outta-the-ground-lowend-torque cubes that will make your top end worse than it already is.