i want to stroke a 305 to a 335 or 340 whatever it is with a 30 or 40 over bore...(and i dont want to hear any just stroke a 350 to a 383 crap please) but anyway i know about having to notch my block and all the other crud, but will i need to reprogram my prom?? its all ready programed (id call it a stage 3 reprogram for lack of better words) to match it up better with the open breather, headers, full exhaust not cat, hot ignition, etc etc.......also running 1:6 rockers.....sorry if this is in the wrong section, modarator please move this if its in the wrong section

I'll be brutally honest with you - you're the one talking crap.

It's just a crappy way to spend performance $'s. As sofa might say - a lot of maze for very little cheese.

I won't even say "stroke a 350 to 383", because the 350 is a whole bunch better than a stroked 305.

There isn't any "right" place to post this, because doing it just wrong.

I dont want a 350 did I not make my self clear, Im tring to be nice about this and your acting like an *** if I wanted a 350 or a 383 I would ask a question about one, if you not going to make a post that helps people than make no post at all, some of us like to be diffrent, like the guy on here who wants to put a 4.3 in his 3rd

I think stroking a 305 is a great idea. It's an uncommon combination, I'd rather have a 334 stroker then a 383 stroker for the originality factor alone. Don't forget that you'll get better mileage and also slightly better torque down low vs a 350, right where you need it for daily driving.

To answer your question, to get maximum performance and mileage, you'll need to re-tune your computer. You could probably get away with your other prom, but it would be far from perfect.

I'm helping more than you apparently realize. I'm not being an *** (and watch your language), I'm being realistic. You can be sure that I'm am not going to allow another flame-fest on this forum about stroking a 305, because it's been argued ad naseum in the past, and it is clearly a non-positive-benefit performance-dollars approach; nothing you can say will ever change that. And, the more you argue about it, the sooner this thread will get locked.
There is absolutely nothing "original" about it, nor is it "great". It was first done over 2 decades ago - it was a bad idea cost/benefits back then, and it's no better (and probably worse) now. It is "uncommon" for a reason. "Slightly" better torque? Certainly too "slight" to justify the cost.

Hey dude I'm all for positive debate on an issue and I know that it's not a "new" combination at all. But seriously, when was the last time you talked to a guy who had a stroked 305 in his ride?
That's what I'm talking about when I say originality. With a stroked 305 you'd be one of maybe a handful in any city you reside in.

Is the benefits of stroking a 350 "slight"? Most guys would say no. Then why is stroking a 305 such a bad idea? Anything you can do to a 350, you can do to a 305 for almost equivalent gains.
I ran some combinations through Desktop Dyno to see what I came up with.
Stock Vortecs, 10:1, Big block TBI, Small Tube Headers with Mufflers, Comp XE256H non roller cam.

305 --- 321hp@5500 360ft-lb@3500
305 stroked --- 324hp@5000 382ft-lb@3500
A gain of 3hp and 22ft-lb or a 6.1% increase in torque

350 --- 329hp@5000 403ft-lb@3000
350 stroked --- 328hp@4500 433ft-lb@2500
A gain of -1hp and 30ft-lb or a 7.4% increase in torque

So as you can see, the difference is nearly the same. Just my opinion, but if you have a 305 to start with, it's a good base. Not every guy wants to go to the junkyard to find a 350 block. Since I also don't like flame-fests, this will be my last post on this issue.

LOL oh my god. Your #s from your virtual dyno are way off. You do realize that people see big HP gains building a 383 with all the same parts as a 350? The virtual dyno is a very rough guess at best, and it's only as good as the info you put in.

And yes, you will need to totally redo your prom. You should burn your own chips and datalog with a wideband O2 for a crazy project like that. Anything you get off the shelf or through the mail is junk, as far as chips go.

Is there anyone out there that thinks $800 for 3 hp gain is a good deal or a wise use of hard-earned performance $'s? Or that a 350 will only have 8 more HP than a 305? Or that a 383 will have 1 HP less than a 350?

Tell you what, since this is really a TBI tuning question, we'll send this over to the TBI forum. If the guys there feel like addressing it, I'm fine with that.

The prom part is easy. Just like a carb or anything else youll have to retune it once the motor is complete.

As far as being different, the 4.3L is a lighter powerplant (3/4 of a 350), so its a good choice if you want a near perfect 50/50 split weight dist. Externally, a 305, 335, 350, and 383 are all the same and similar in weight. The 350 has the advantage of larger cylinders for larger valves, more cyl. volume, and more power. The 383 has everything a 350 has and more stroke. Theres not a whole lot to be gained from using a smaller bore motor and more to be lost. Some things to consider before you spend money on the 305. Id personally just say leave it as-is and upgrade the heads and cam. This will make about 2x the power of just stroking the motor and keeping the stock heads and cam.

I agree, spend those dollars on good heads and cam. The heads can be used later on for just about any sb build. Going extreme on cam and heads will be a chore to tune aswell. I love my 305 (we share a twin size bed), but still stroking it wouldn't be as usefull as heads and cam combo. you could easliy see 360ftlb with an extreme combo. Not that your idea is bad at all, just that when you go to machine the 305 the money you could spend on heads cam combo would out wiegh hp per $. Not to ramble our insult, after all you did say you wanted to stroke and not to tell you to go 350,but what i'm saying is..........it's a waste of money.....unless of course your reallllly insane and do it all, stroke + heads, cam combo. which may just make you as happy as a pig in poo. more power to ya.

i kinda like the fact nobody does it, the power gain aint worth a crud wagon i know that, could care less if it has 100hp more or less than a 383, its not going to the track or anything, i just like when someone rides with you or whatever and cant belive its a 305 block....if i were to do it i would get good heads,cam, intake combo

Unfortunately people will always tell you not to do it. It just comes with the territory of building a 305. They think they're doing you some kind of favor, as if they are enlightening you to the fact that a 305 makes less horsepower than a 350. Duh. I'm persoanlly tired of hearing both sides of the argument. Although if someone doesn't know that a 305 is less powerful than a 350 then they shouldn't be building anything! If insane horsepower is your ultimate goal, then a 305 is not your friend. If you're just building a motor, want it to make a good amount of power and you have a 305 waiting to get built (I have 3), then why not. It can make a fun motor and can still be decently gas friendly. As far as stroking a 305, well thats more money. Certainly more than a stock rebuild. If you feel like it go ahead, it will make more power than the 305 will with just a .030" overbore. It's up to you if you feel it's worth it, even if it is just for the confunsed look on your friends' faces when you say "it's a Chevy 334."

No where in this post did I say a 305 or stroked 305 would make more power or torque than a 350 with the same parts installed or money invested into it. It won't. Ever.

As far as the original issue is concerned (prom), you will need to tune it yourself or have it tuned by someone. As mentioned, off the shelf proms won't help you.

Do what you want, don't worry about what everyone else thinks. If the 305 is your thing, good for you.

As far as the comments about 305's vs. 350's. This is supposed to be a Third Gen family, so start acting like one and give your fellow Third Geners some support and less criticism. Telling someone that they would be better off with a 350 vs a 305 is one thing, but when you start telling them that what they have is crap and is not worth working on or doing anything too compared to what they could have with something else is not what this site is supposed to be about. We've all heard the arguments over and over again, so give it a rest allready. Allright, I've done my preaching for today.

Can I get an Amen? Allright, now im done.....

Sure.

As long as it isn't couched as the "right" thing to do.

Or the best way to spend your money.

Or that being different justifies it.

Or that it's the only way to get confused looks from passengers that it's a 305 block.

All of the goals can be obtained without spending the money on a 3.75" rotating kit.

(And I never said what he had was "crap". What I was getting at was the premise was.)

Nobody jumps off bridges, does that mean its a good thing to try just to be different?

There is a reason why people build 350 and 383 engines. They are less expensive, the combos are already set up for you by people who have done it, and the parts are more plentiful.

No you did not call it crap, and I was not saying that you did. I meant most people on this site call the 305 a dog or crap engine and automatically jump on the 350 band wagon. Anyone that has been on this site any amount of time has heard the argument and most likely does not want 30,000 people screaming "don't do it" every time they mention doing something to a 305.

He described in his post that he wasn't interested in a 350 (although he could have phrased it in a less demeaning way) and the first post you made went straight to the 305 vs 350 argument and nowhere in that post did you even address his initial question. You even went as far as telling him that it was just wrong. What's right for some is not right for all.

As far the being different part, it very well may be completely justified in his eyes just to be different. There's nothing wrong with being different.

"Nobody jumps off bridges just to be different" what kind of comparison is that, really?

Allright, I'm not trying to offend anyone, that's just my opinion.
And you know what they say about opinions!

As long as he doesnt keep the god awful stock heads and cam it should do alright even with the smaller bore.

Now would also be a good time to mention that youll also want to upgrade the computer to something else like EBL or a PCM. The stock ECM will really hold it back due to how limited it is.

whats the difference between a PCM and ECM? what is involved in swapping to a PCM rather than having an ECM?

The PCM was the latest and greatest to come from GM for TBI. It was much more versatile. It has lots of new features such as vastly better idle control, seperate spark and VE tables for run and idle, TBI or TPI/MPFI firing modes, faster ALDL, better fuel control, support for the 4L60-E and 4L80-E, etc. Basically you have to buy the PCM from a j-yard (93-95 TBI trucks had them) and connectors and repin your harness. After that you edit the prom to select the correct transmission and engine options and calibrate it to your motor.

This has ALOT of information about converting a TBI system to the PCM and a 4L60E in place of a 700r4.

http://www.thirdgen.org/techboard/tb...i-project.html (3.1 TBI Project Update)

$$$$ not a issue, i know it will cost more than a 350/383......plus the wierd look you get as metioned before when you tell people what it is, is always cool......i seen the posts/article on reburning your prom wondering a little more about it... dont see the need to spend that money when i can send mine back to the guy who burned mine in the firstplace, costs under $100 for a custom reburn, with a life time warr.

can the newer style computer work with a 700R4? i just spent bookoo $$$$$ to build my 700 almost bullet proof and super fast shifting......hate to lose all that $$$$ just spent, it has less that 1,000 miles on it < and lays rubber like the smilly just did LOL

But he'll never get it right unless he is right there in your car seeing the live data. Otherwise he's just guessing. You get what you pay for.

I too agree that you have to do it yourself. No other way to do it.

EBL still supports the 700-R4s and manuals just like the ECM. The TBI PCM supports manuals and most longitudinal 4-speed autos (700-R4/4L60, 4L60-E, 4L80-E). Read up on each and see which one you want to go with. Id definitely upgrade to something other then the stock ECM, as it really sucks.

anyway...............the progaming look like it has alot of steps, not hard i dont think.....but how much computer skills does it take to do this? like scale of 1-10 ...... 1 being someone who has never turned a computer 10 being the guy that makes websites and designs video games and also give me the "simple mans terms" on how a get this "live data"............down the road when this is all said and done (have no idea when) i like to get a real dyno run just to see what #'s we are looking at before and after the computer work on the prom.

Its not real hard, maybe a 4. Does require some computer skills to get it done, but nothing you cant pick up. More then anything else, it requires a good knowledge of how engines work. If you dont have a good basic understanding of whats going on, then your just plugging numbers in.

yea sound like i can do it, just not real good when it comes to some of the modern computer cars, but 89 is such a primitive computer, i think i will have no problem....... just glad it isn't some kind of act of congress

still how do i get the live data to know how to adjust it my setting

I recommend reading the stickies and doing a search on the subject. The information is all around you here. But basically, to aqcuire the information you'll need a laptop computer, datalogging software (which is available for free), and a cable to connect your ALDL socket in your car to the laptop. As far as the cable goes you can buy one for quite a bit of change, or make one from parts available at radio shack for less than a $10 total. That will at least give you the ability to datalog and see the information your ECM is generating.

read the tech thingy, just wanted it in little bit easier read format, just to figure out if its worth the hassle.....looks worth it to redo the prom

I wanted to do this with my camaro when I had it just to be different. If money is no object and being different is what your after there are better routes. You could always build a 327 by destroking a 350. I'm sure you've never heard of a 374, cause I know I never had before I read super chevys 374 vs 383 build. In case your intrigued a 374 is a 400 block destroked with a 350 crank.

Its all up to you but personally if I was out to build something different it would be one of the above. A 327 shows alot of respect for GM muscle car routes. They're the little small block that could that dished crazy numbers(for the time) in early 60's vets. Then theres the 374 which just makes people scratch their heads and go wtf came up with that ci.

yea the de stroking the 400 was another idea.... just havent had good luck finding a 400 block........305's are everywhere here, im not doing it to my stock one as i was the original casting #'s to match my year for later on down the road, i figure get a 305 from a truck, that way if something happens to it i destroy a block that means nothing to me as its casting numbers are not to my year...... should of also said a little different about the $$$$ no object, its not a MAJOR issue, but not a top concern.

Even if you were to stroke the 305, which isnt as hard or pricey as people like to say, you would still likely need new heads and a new intake to get the performance out of it. I would wait until you absolutely had to tear into the lower half of the motor, before even considering it.

Dude...you should do whatever you want...its your dollar...spend it how you want...I like the idea. Fast actually built a 305 that had big power...so it can be done and its economical on gas too.

You should at least read this article...I know its an LS series but it is still a small cube mouse that puts down 435 horsepower at 6000 rpm. I don't know if you have ever thought about an LS swap but if money isn't a problem then...it would be a cool idea....its kind of a "Flashback" engine from 1969.

http://www.auto-power-girl.com/speci...o_concept-1134

Camaro 302 Concept

The engine was built by Norm Brandes of Silver Lake, WI. I know the guy and he is pure genius...he'll put what ever engine he wants in any car...he has no problem letting is creative genius run wild. He just built a 383 topped with an Accell 4 Barrel FI system for a guy I know here at work and it put down 650hp at the wheels....I don't even know the TQ numbers...I guess you can use your imagination.

JB

Check this website out. He goes into the particulars of every thing that you ask. He goes step by step, addressing TBI upgrades, intakes, heads and finally stroking a 305. It really isnt as hard and expensive as some of these guys say, you just have to do your homework first.
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http://www.goingfaster.com/spo/modthel03.html

Ohh god no.....it's ......I can't say it..............it's "THAT SITE".


That guy is completely clueless and most things he says on there is dead wrong. To find out how to make power with TBI just read the stickies at the top of the page.

That site comes up every couple of months, it's like the black echo bouncing around the net.

I dont think that he is completely wrong, but he is too enthusiatic about it. I wouldnt stroke a 305, not because of cost, but because of reliability, and like I said before, in order to get the most out of it, you will still have to completely change the top end anyway. In the end you basically end up with a 350.

well i was planing on going with a little bit bigger cam, a ebelbrock TBI intake with a sprial spacer, some brand of a higer CFM "Chevy TBI" with bigger injectors a good set of heads off of Jegs, and a good set of 1:6 rockers, not going forged on the bottem end, getting Keith Black hypereutectic pistons, not sure on my connecting rods yet , going eagle on the crank, and a gear driven timing also.

regardless i liked the websites, as said before i think he is a little to happy about it but it was worth a look wierd how the nubers on the lift on the edelbrock cam are small, seems all the do is give you a little more "cam lope" . no bodody has to prove or sell to me that you can get some good #'s out of a 305, seen it with my own eyes on some 305's


i may have to make another post for the next 2 ?'s i got but i will try on here first, does anyone know a good aftermarket direct plug in bolt on TBI unit with better #'s than stock, and the next one is how radical of a cam can you run with TBI and a reprogram on your prom

Ive seen some on summit and jegs that advertise flow above 600cfm. I think that they are truck units. Sounds like you did your homework. Which I bet some of these guys dont do. Stroking a small block chevy, is relatively easy and cheap compare to a ford or mopar. I would consider talking to crane and getting a custom grind for your cam. The problem with any computer controlled motor is it monitors airflow via the MAP and Vaccum. Big cams decrease vaccum, so a custom chip will have to be a must. Im not sure that I would do what you want to do, because of reliablity issues (trying to make so many mods work at once), but I basically did the same thing with a small block Mopar. It runs like a raped ape.

LOL....what BMmonte is trying to say is that...uh...he never wants to see that link posted up on Third Gen ever again! LOL...hold fast BMmonte...hold fast...LOL....

Unfortunately...there are a lot of far fetch theories on that and although the idea is there...the guy wrote it during a time when TBI was in its infancy and the knowledge was limited. I don't even think TBI tuning was barely up and coming at that point. The TBI after market consisted of Jet Fuel Pressure regulators, Hypertech chips, Holley after market TBI's...etc...etc...and on Third Gen...TBI was brought to the forefront on the backs of a dedicated few like Grumpy (not forgotten) and other early TBIr's.

Well...Xtreme FI has good bolt on TB's that are made good. I have talked to a lot of guys that have bought them and they are done right. Some people have said they did not like their fuel pressure regulators though. CFM Technologies and Turbo City make good higher flow TB's also but be prepared to drop and arm and a leg for one from them.

As far as a cam...I have always been told to look for an LSA that is between 112* and 114* to allow for proper idle because a cam with too much lope won't allow it to idle without a vacuum assisted pump to run the brakes and accessories that need the proper vacuum to function properly. I called Comp Cams and they said they have computer compatible cams that are good for some stock PROM's...they also have a list of cam's that need PROM tuning, gears, high stall torque converters..etc...etc...I would say call a cam company to start out and then bug one of the TBI gurus for some advice on the ultimate one.

I think the LT1 cam may be a good choice for you to start with...I knew a guy that had a Caprice with a 305 and an LT1 cam and he actually had some good success with it at the strip. I don't remember his E.T.'s anymore but he was doing all right actually...I think he was pretty close to alot of stock 9C1 350 TBI Caprices. Its been a while but I rmemeber that his numbers were decent for a 305. He had true duals w/Tri-Y's, some slight head work done...1.6 rockers and DIY port work. Put it this way...he had beat that engine up so bad...he started suffering from crank walk...

Preach on brother John....bring that beutiful tbi tech


Like John said there are very few cams that will work with the stock programing. The reason for this is simple, TBI is a speed density setup and the only downfall of this setup is that you MUST retune for any mods that make more power. Once you are able to tune you can run ANY cam with TBI, being able to tune is like having a whole box of jets, springs, and boosters for a carb.

89formula=happy vbmenu_register("postmenu_3487459", true); i seen the truck units as far as i know they are the same as the camaro, except for later models that had 2 hold downs for the breather (WTF?!??!) ............ as for the cam issue i kinda want lope, regardless if i need to add an aditonal vac canister, maybe a 278 duratuion would give a little lope with good vac, to me half the fun in the cam is the lope (and solid lifters sound even better LOL but to much trouble to keep adjusted unless the is some new tech in the solid lifter cam industry im not aware of) put it this way i get it form my dad, when i was a little kid we had motorhome to a 454, it had headers, glass packs, and a nasty sounding cam, along with so other mods, well i fell in love with the lope ever since.....hell we got a motorhome brand new in 1996 and the first thing my dad did to it was get the Gale Banks intake, headers, exhaust and computer....... i guess it runs in the blood wish he was still around to see my camaro but...., anyone see the TBI's on ebay that are high CFM??? i rather go with the holly ones in jegs......another question, or asking opinion....should i go with a edelbrock TBI intake, or get a bigger carb intake and use the TBI adapter?

as for the ECM i know the guy that burned my for my curent set up, well that burn was like night and day..... anyone know how radical i can go (cam wise) with that TBI and burning a chip with the factory 89 ECM

I have a flat tappet Comp 275 DEH flat tappet hydraulic camshaft with around 1500 miles on it, with matched and numbered Comp lifters, that I just pulled from a 327 in order to do a retro roller cam install. I was running the Comp 275 with MAF EFI (custom tune by me of course) and a Stealth Ram on top. It has a nice lope to it at 800 rpm idle but it still made great tire burning low end power. I could make you a great deal on it if you PM me.

dang it, my power went out and i had a long reply typed out.................

but anyway as said before i want a cam lope........ but i want TBI to keep it as stock looking as i can.....lope IS an issue, if im going to put a cam it in i want it to lope, but anyway thanks for the help so far

If you want it to lope, you need to learn to burn your own chips. No way around it, if you know some one close that can burn a chip with the car in hand then you are better off. Keep in mind though that with a really big cam the stock ECM is lacking. You would do yourself good to look into the EBL or the newer PCM's.

You can get away with a lope with MAF TPI with no tuning. That is one of the reasons I used MAF from the start -- since it ran decently with no tuning I figured it would take a lot for me to screw it up, since it is actually measuring airflow.