I wrote them the following letter today.

Hi my name is Chris and I am a fellow TBI modder and enthusiast. Let me be the first one to congratulate you guys for doing the Mission 305, Vortec TBI swap. 305 TBI cars make great little performers when the right mix of parts are added to them. Modding them has become increasingly popular these days and strays from the normal "get a carb 350" mentality. I have a couple of questions though regarding your swap. As a TBI board moderator on www.thirdgen.org I have accumulated multiple emails and responses from people who have similar set-ups with sub par results. The consensus from the members seem to be a little confused how you guys got your numbers, or in that fact how you got the car to run. Your parts selection was perfect and the best TBI modders out there could not have picked a better combo. However, we are all in shock that you guys could get the car to run throughout the whole powerband and make that much power with the stock computer tuning. Pretty much all TBI cars that have an aftermarket cam will not run properly. They will sputter and run horribly rich. Ones with head swaps run even worse. This is only cured through computer tuning and upgrades to the fuel system. Most TBI cars with heads and cam swap will run slower ET's because they are using the stock tune combined with the inability of the stock fuel pump to maintain the necessary psi for WOT fueling. We are all simply floored that the stock tune worked so well with such a big cam and high flowing heads for your test car. We always recommend a high flow fuel pump and an extensive amount of computer tuning when suggesting cam swaps. They go hand in hand and should always be added to your cam swap parts list. We hope that your readers do not take your numbers to literally. I think you will find that with your planned dyno tune you will be able to change the chip and make much more power along with the car having better idle and throttle manners. You will also find the limitations of the stock injectors once you get your tune dialed in.
I noticed in your article that you mentioned you have yet to hear of anyone with this swap. There are a few board members, including my good buddy, that have done the vortec 305 TBI swap. Most go with a vortec carb intake with a TBI adapter plate. They all had tuning and fueling problems at the start and ran horrendous ET's. The ability to burn your own chips is essential to dialing in the right tune with such a swap. It is fairly easy to do and usually takes a few data logs coupled with a few re-burns to get the chip right. All have since done that and their cars are running much better.
Anyway, great article and I cannot wait to see the results of your dyno tune with the larger TBI unit. Feel free to check out the TBI forum at www.thirdgen.org. It is one of the best resources for TBI tech and advice on the web.

 

Hey guys great news. John Nelson from CHP got back with me and wrote me the following. Turns out the car didn't run as well as we all believed.

"Chris,

To be real honest with you, I'll be damned if I know how we got the numbers, either. I was on deadline and ran out of time for tuning and high-flow throttle body, so we threw the car on the dyno with the stock stuff on it, and that's what it did. I d idn't mean to imply that it ran well, 'cause it really didn't, but those were the peaks it put out. Then again, we put it back on with the new throttle body and chip, and it ran like crap. Then the thing seemed to adjust to the new tuning--I don't know if that's possible--and we made numbers that make what you saw look sick.

Our delay has been becuase we blew the .015 gaskets. But even with .039s in its place, and with the new chip and throttle body, this thing is a monster. I didn't want to believe it, but we've backed up the runs, and verified the dyno, too. Let's just say that this thing we built is regularly kicking the crap out of a '97 SS. Again, I didn't want to believe it, but I've seen it.

I guess I need to check out thridgen.org in a bit more depth. I use the info and specs areas pretty regularly, but haven't went much further.

I'll be back with part 2 in our September issue, and all will be explained. I may also address some of the issues you've brought up--our builders haven't recommended a higher-flow fuel pump as of yet, though both throttle bodies have adjustable regulators on them. We'll also make a trip to the track to see what's what. I'm not gonna make any predictions, but this is one vicious little RS. If this is what throttle bodies are capable of, I can't wait to start messing with my crossfire Vette. "

 

Looks like the september issue will be interesting, I just hope it's beliveable and they have track times to back up their figures.

Steve

 

wow thats neat, CHP is a quality mag

Im not sure a higher flow fuel pump is absolutely necessary. I know of people who have pushed them into the low 13s. I cant comment on the actual flow ratings but I dont think the thing is that stressed to meet the flow requirements.

The one thing it lacks is the ability to withstand high pressures though and that is one of the most important peices of the puzzle when it comes to TBI modding since we only have a limited assortment of injectors and our stock injectors can handle so much fuel pressure


I hope they have some track times too (hey CHP if you are reading this bring it down to carlsbad raceway in a couple of weeks, ill be there with my 305 and we can race )

 

What does a 97SS normally run? ET's? HP?
Do you all think this is true?
If all this is true, what do you think the HP, TQ, and ET numbers look like for this "vicious RS"?

 

Hmmm.... Maybe a key point to their swap was the .039 gaskets? Maybe the computer reacts easier to the lower compression. I'm running a milled down .030 head with .015 or .017 gasket. And I think Chuck's is close but not as high as mine. But I have seen the prices on Turbo City's chips, they are really expensive for custom burns. Maybe they cranked out a nice tune for them, especially since they picked the cam. I may have given my left nut for my car to react that well that quickly. To bad we gotta wait till september.

 

From the numbers I've seen posted a SS LT1 was 305 hp and LT4 SS was 335. Probably both mid 13 cars.

 

My heads are milled .020 with the .015 gasket, so Im real close to you fast lookin. Their heads were decked .060 so even with the .039 gasket they still got a little more compression than us.

I just have a real hard time believe that it put down 220 rwhp untuned. I still dont have any wot tuning, only fuel pressure with the stock throttle body and my traps are consistantly 91 mph, I pulled a 93 but that was on a slow 60. I'll tell you that without tuning you lose just about all torque. Id be really interested if they would post a stock dyno graph, if they are making 220 rwhp I bet its very peaky and the torque curve is horrible, not flat like it would be with proper tuning.

 

Chuck is right on. John, the editor of the article acutally called me today to talk about the car. He said that the car made great numbers but were all above 3000 rpm. He said the dyno graph below that was choppy and all over. He also enlightned me on asome of the future projects for that car but I will not tell until the articles come out. With Turbo Citys new TBI unit (not the one they have been selling all along) they are hoping to get some great track numbers when combined with thier tune. John told me how hard the car pulls up top and said that they have beat a C5 and 97 LT1 with the car so far. We all know anything on the street is possible but that is not the point here. So keep on the lookout for some of my quotes in the next article.

 

the chopiness a tuning issue? Also, i read that article and I saw that they kept the EGR setup working and that they're based in California. Is it really possible to get that thing to pass Cali's strict emissions laws?

 

They should pass the sniffer without a hitch. They have EGR and AIR entact. I would worry about visual inspection. I never thought to ask him that yesturday.

 

yeah, i would like to know that also, because i was thinking about going with vortecs on the 350 i plan to get within the next year or two.

 

good point w/ the visual... i was wondering though, you think the emissions people are likely to know exactly what the EGR setup is supposed to look like? Down here in texas where im at, they really dont give a crap whats under the hood or been done to the exhaust is as longs as it passes a sniffer. I, luckily, dont have to pass a sniffer yet but i do have to pass a visual, which has NEVER once been done to my car. In fact, i've never had to even get out of my car to get the sticker. just a simple five minute procedure where im from. But i know the sniffer tests are coming so im trying to plan for the future. Goodbye vortec headed 383 of my dreams...

shifty, you say they should pass emissions with ease. I take it that would be after the tuning cause i remember reading an article on this site that HC or something came from rich/lean conditions. After their tuning is squared away, the car should pass? Thats a little suprising b/c thats a fairly decent size cam they have their and they're using 1.6 rockers.

BTW, Why the hell is the engine so peaky? I didn't think the cam was that big

 

They should pass after the tune. As it sits now I doubt that they would. The cam they are using is really big for a 305 and it will make its bet power up top past 3000 rpm. However, they should still see power gains down low compaired to the stock cam.

 

bah, thats not a big cam

 

you know, learning that really bugs me. in the article, they definitely lead us to believe the car has great power AND driveability. i'm sure it'll get there, but i'm also sure there are tons of less informed tbi owners who will read that article and try to duplicate it without the required chip tuning.

 

they say "...we were able to tap into the Edelbrock TES headers for exhaust gas, thereby keeping the Golden State's smog police happy"
I take that as passing the sniffer and visual inspection because there is no way you can make the CA smog people happy unless you have a car that will pass visual. If i was one of these less informed TBI owners and i did this to my car and failed smog (visual) i would be PISSED.

 

Yeah, me too.

Actually, I have the Hooker 2055's on my car (smog legal), and I FAILED my emissions test w/ flying colors. It turns out, that if you run a VAFPR (such as myself), and you richen up the mixture a little bit, you end up failing the NO part I believe. Oh well, I guess I be emissions legal for about 30 minutes this week.

 

I made sure to mention that to him how important tuning was. Sure the car pulls hard but only after 3,000 rpm. Fear not though , the next article should make everyone happy

 

Gunny Highway.....what county are you being tested in?

 

Cherokee

 

A good vortec head article::::


http://www.chevyhiperformance.com/howto/97458/

 

just picked up the new chevy high performance .... no part 2 of the 305 tbi project

: (

 

Damn, it's out already??? Besides the fact that we got robbed (intimidation maybe?), how's the mag otherwise?

 

its gonna be in the September issue, not this one, this is July's issue

 

Correct. John told me to look out in late august when it comes out. Man that is a long wait.

 

well, we should get September's issue by mid July because its only mid May and i just got my July issue

 

Anyone know where I could pick up the released issue? They are not available locally.

 

Check out their website for a subcription. Any news stand will have it. Even Krogers, meijer, walmart etc etc.

 

man, getting subscriptions to those magazines was one of the worst thing i ever did. last august, i subscribed to hot rod, car craft, super chevy, gmhtp, chp and pop hot rodding. the "free issue" each of them offered with the subscription turned out to be the one currently on the stands, i've gotten dozens of spam emails and telemarketing calls, despite the fact that i opted out of their "special offers by phone or email" option when i signed up. three months after i signed up, i started getting "don't let your subscription run out!" junkmail (i've gotten over 50, so far, and they've all sent issues with covers on them saying "this is your last issue" this month, even though i'm supposed to recieve one to two more of each (depending on the magazine).

what a ripoff. i can find one saturday a month to go to my local newsstand and spend an hour leafing through the car magazines, buying only the ones i really want. their loss.

 

Well the latest article is out and the results are. Although they will have track times at a later date they finalized thier vortec 305 buildup with 257 rwhp and close to 300lb ft. They didn't go ingot detail about the tuning since the guy that did it apparently likes to keep it "secret". Well, my geuss is that his secret was just data logging and burning a whole bunch of chips until he got it dialed in like the rest of us. In the end, it is slick build-up that shows what these little buggers can do with the right amount of detication and money. People rarely take them this far because of sub-par results mostly due to their own niave sense of TBI. Now that we have seen the light on what an unlimited budget can do to one of these things we can put the "TBI is junk" to rest. I will try to clean up this thread and make it a final sticky with all the tech stuff you need to compile such a swap. Make sure you chime in if you have any added tech to this saga.

 

new story jsut came out, they didnt really go into detail and they didnt mention shifty capones input, guess you missed out on our fifteen minutes of glory dude!

 

Read the letters section I'm there My letter was cut short in the mag for obvious space reasons but he appologized in the article based on what we disscussed during our phone conversation back in april. He didn't go into enough detail on how the car behaved with the stock tune and I brought that to light as to not confuse his readers.

 

i've been doing a lot of thinking about vortecs since reading this article. i thought it might make sense to look into rebuilt vortecs as an even lower cost alternative to the sdpc heads.

there's a head rebuilder i've done business with several times and have been very satisfied with the price, quality and service. i called him to ask what he'd want for a set with the seat and spring upgrade and milled enough to bring the combustion chambers down to at least 60ccs. he said he'd strongly recommend against it, that the heads were prone to cracking in stock form and milling them the .030-.040 necessary to get to 60cc chambers would make them even more vulnerable to cracking. he went on to stress how serious a concern this was, saying the main reason rebuilt vortecs are so much more expensive in relation to the price of new replacement heads than the many other heads he remanufactures is the scarcity of uncracked cores. he said he has to throw away more than half of the vortec cores he gets in after magnafluxing reveals cracks in them.

what he did recommend was looking around for pro-topline vortecs. he said they're getting hard to find, but they're not prone to cracking like gm vortecs, have enough deck thickness to allow their being milled to 60cc chambers and even flow a little better than gm vortecs.

out of curiosity, i checked with two other head remanufacturers who do vortecs. they said the same thing. when i mentioned chp's milling more than .060 off of a set to one of them, he laughed out loud, saying he could virtually guarantee they'd crack within 20,000 miles use.

i remember seeing the pro-topline vortecs all over ebay this time last year. i checked today and don't see any. did they stop manufacturing them?

 

wtf! I didn't get mine in the mail yet!!
That mail man better have not swiped it, I'll kick his a**!!
LOL

Oh well I guess I'll sit here and hope it comes in tomorrow!

How come CHP doesn't find a Camaro owner that will let them do what they want to the engine? Like swap a 350 or stroke an engine? I think that was a poor excuse to mess with the 305!
I think they just wanted to throw something together so they would satisfy us TBI guys a little.
I don't think that's right!

 

The 305 TBI build-up was a nice change for them. It makes for good reading material and tailors to all the millons of people out there that have TBI equipt f-bods and trucks that cannot afford a carb build like you find in 99% of their articles. Who wants to read the same thing over and over. I bet their fan base has jumped big time.

Sean,

They did mill the heck out of those heads but you do not have to go that low. You can safely go .020 from what I understand and use a .015 gasket and have a CR about exual to stock. Chuck! runs this exact same set-up and his heads are just fine after tons of abuse and 20K miles. I thought the Pro Top line heads were still in production. They are the better of the two like you said.

 

man, i wish someone definitively knew how to calculate the effect of milling on combustion chamber size.

i found out this evening that pro-topline went bankrupt and is in the process of reorginazation. i don't think they're currently producing heads.

they've also stopped calling their vortecs "vortecs". i was told gm sued them over copyright infringement. here's a link to their vortec replacement head that's no longer called a vortec: http://www.protopline.com/2236494906.asp

there's also something VERY interesting on their price page. it's not listed anywhere else, but check this out:

223 5894 059 Pro- Stock Replacement 305 - 58cc chamber 1.940 Intake valve $463 (pair) $232 (each)

if that's a 58cc version of their vortec head, that would be awesome! i've emailed them about it; we'll see. the price they list is for bare heads. sdpc2000.com lists stock bare vortecs at 249.95, and they will still need be milled for compression and have the seats cut!

 

That would be pretty slick. I wonder if they are similar in design to the 305 GM vortec heads. Hopefully much better. Make sure to respond back with their reply.

 

dude, are you nuts? the commonly held belief among virtually everyone is that the 305 is a total piece of junk and isn't worth messing with. these articles prove that wrong; emphatically. when you factor in parasitic driveline loss, 257 rwhp works out to well over 300 flywheel hp; and look at the torque! they're in a position where that lowly 305 can run with mustangs and lt1s!

i still think it's crazy to put money into a 305 shortblock, but this project proves it's also crazy to just write off a perfectly good 305 already in the car.

 

Don't get me wrong, I think they did a great job, and made alot of 305 TBI owners worthy!:hail:
I would have rather seen what kind of monster they could really build, if the owner would let them do what they wanted! I mean these guys have the tools and money, most 305tbi owners are either going to swap a whole new FI system in or do the 350 tbi.
Well there's always hope they will do a TBI build up again!

 

Well when I talked to John the reason they kept the 305 was because it only had 30k on the clock. The owner did not want to stray away from the 305 because like us, he wanted to keep it and make power from something that most people throw away.

 

I understand that, I read it in the mag.
But in reality, how many of us on this board are running around with 305s that have 30k or even less than 50k at that???
Not many of us, we'd have to open up engine any way. So why not just throw in a 350 like most of us have done or plan on doing? I'd would like to keep my 305 and make power but I'm sure at 150k+ it's probably not making enough compression, rings and piston sleeves are probably worn?

 

i'd bet there are 10 times more 305 tbi owners on this board who still have their 305s than those who have swapped to something bigger. my car is a perfect example. i bought it a year and a half ago running perfectly with 90,000 on the clock. it had been well maintained and the compression and leakdown check i ran on the car before buying it were good, so i made no immediate plans to do anything to the engine.

last summer, i broke an exhaust manifold stud off in a head while upgrading to headers. then i broke the easy out off in the stud trying to get it out, so i had to pull the head. the cylinder bores looked perfect and the guy at the machine shop who drilled out the broken stud/easy dissassembled the head and said it looked great, further validating my decision to stay with the 305 till it's used up.

you see people posting on here all the time saying they want to swap in a 350/383/406 etc. but, when you talk to them, you usually learn they're expressing that not so much because they need to swap engines, but because they've been led to believe any money they put into their 305 is totally wasted.

i, too, would like to see a swap done on a tbi f-body, but not as much as i wanted to see these articles. most people on here are modding their cars on a budget. it makes economical sense to both get as much use out of the 305 as possible and to do all of the infrastructure mods one-at-a-time as money allows, saving the swapping to a 350/383/406 short block till a later date.

truth is, if you do it that way, by the time you actually do swap short blocks, you'll know enough about the car and tuning it to actually be able to make the swap work.

 

You are right about the budget part.

Well since I haven't got my mag in the mail I haven't been able to read up on it. What TB did they end up using?

 

A new turbo city unit with 1 13/16 bores. They bored out a stock unit. They are now currently for sale.

 

Congrats Shifty!

Good to see the TBIs get some coverage.

But just port and polish a set of 081, 416 or 601 heads yourself and you will save a fair chunk of change because you won't need a $250 Vortec intake as well.

F-Bird'88 has gotten them flowing just as well as Vortecs but this all only costs about $350 to $400 total. Plus you can use your stock intake or just go buy a fairly inexpensive single plane.

Follow the link at the end of my sig

 

that's misleading.

first there's the cost of the heads. say you pick a pair up for 100.

then you have to get a valve job. 150 at the machine shop if you don't need any valves, guides or extensive seat work). you're now at 250.

if you don't have a die grinder (like most of us), you'll have to buy one. 80 bucks or so.

then you'll need the head porting kit. Jegs has it for 39.99. after shipping, figure 50 bucks.

when they're done, you'll need a set of springs. 75 bucks.

then there's the manifold. if you're still running the stock one, you'll have to get another. edelbrock performer tbi. 225.99 (plus shipping) at jegs (there is no savings in running the single plane. the weiand 7525 is arguably the best intake choice for tbi. carshopinc.com sells them for 209.95 and you need an adapter that sells for between 25 and 50 bucks.)

you now have 455 bucks in these heads (over 780.00 if you count the intake), not including the hours and hours of labor needed to get the porting done. and since the average diy'er doesn't have access to a flow bench, there's no way to be sure you've gotten it right or if the respective ports flow evenly. and, at the end of all that, you still have a set of heads that only flow as well as vortecs, AT BEST.

sure, you could save some money. maybe someone gave you a set of heads. maybe the heads looked ok so you skipped the machine shop (crazy, in my book). maybe you have your own die grinder and your next door neighbor's brother-in-law's boss' second cousing already has the head porting kit and will loan it to you. maybe you can pick up a set of used or off-brand springs at a swap meet (crazy). maybe you can find a good used intake on ebay.

maybe.

here's a simpler way. call jim at tri-state cylinder head (800 270.0095). he sells pro topline vortecs for 450. they're an improved design which aren't prone to cracking, don't need the seats machined for cams with lift of over .460 and already have springs good to .500 lift. after shipping, you'll have 500 bucks in them.

you'll need to have the heads milled. vortecs have 64cc chambers, the l03 has a 58cc chamber. according to jim, you have to cut .006 for every cc, so the 6cc difference would be .036. he wants 150 to do it. that's too expensive. check around your area for pricing, but it shouldn't be more than 100 to do it.

that's 600 in the NEW pro topline vortecs versus 455 to port your own heads. sdpc200 has the gmpp tbi intake for 309.50 versus 225.99 for the edelbrock performer tbi. a difference of 85 bucks.

so, the vortecs over the self port will cost an additional 230.00. also, while you may get the same flow numbers out of those heads, you won't get the same flow pattern, velocity and quench area. vortecs make horsepower not just from how much air they flow, but from how they flow it.

is it really worth hours and hours of drudgery at the grinder, your mouth filled with that iron dust, your hands numb from the vibration to save a little over 200 bucks? is it worth the risk of running used heads versus new, of your screwing up the porting, of the lost power due to the old-style combustion chamber design on those heads?

i don't think so.

 

Well, a whole bunch of us on the thirdgen boards have already done the 305 port and polish routine and are quite pleased with the results.

Why would you pay $100 for an old set of heads? I don't know anyone who has. Most of us get them for free or for a very small cost at the wreckers, usually around $30 for a pair.

Your notion of $455 to do a set of heads is about $100 too much. Read the entire thread, I included a copy of my bill from the machine shop for all new valves, springs, etc.

We can even provide you with a set of templates so you can know when your porting and polishing is done right.

It is NOT torture to do your own heads. Most people get a HUGE sense of satisfaction from doing them and then feeling the additional HP you created with your own two hands.

Give it a try, you might like it

 

i've done a few sets myself. it made sense when aftermarket heads were so expensive. it's not that way anymore. even if you lop off another hundred (which i don't agree with, i hunted a set of 305 tpi heads for over six months and couldn't find a set for under 125). additionally, my costs didn't include valves, which you'll absolutely need. what sense does it make to port them if you don't go to bigger valves? i just got off the phone with the machine shop i use. refurbish heads and install 1.94/1.55 valves. 225.00 (labor) because he has to cut the seats. 175 if i stay with original size valves. i still say, for the average person, the difference is less than 250.00.

you obviously have ported a number of heads and enjoy it. i'd bet you have a nice workbench in a garage to work with and have probably built or bought a variable-speed foot switch, too. what about the guy who lives in an apartment or has to work in his driveway? how many mothers or wives are going to tolerate night after night of porting on the kitchen table?

and what about the time? the last set of heads i ported took me over 30 hours, all told. that didn't include running back and forth to the rental store every weekend to get and return the die grinder (i rented a professional grade grinder after burning up one i bought at sears).

and template or not, it's both critical and difficult to make sure all of the intake ports and all of the exhaust ports flow within a few cfm of each other. the only way to do that is with a flowbench. get it wrong and you can kill the engine. i've seen valves burnt because of over lean conditions caused by head porting creating inequities in airflow. it takes experience and know how to properly port a set of heads.

please understand i'm not raining on your parade. it's obviously you get a lot of fulfillment from doing it yourself. conversely, leave a little room for people who've done it and didn't think the savings were worth the time, effort and grief, or who might like to try it but don't want to buy tools they'll probably never use again, or who might like to try it but don't have the space, etc.

there are guys who live for building tiny ships in a bottle, and there are people who'd rather stick there dingie in a fan than to have to build a ship in a bottle. neither is wrong. one is in a LOT of pain.

 

Sorry the porting experience was so negative for you.

I do agree that decent heads are now getting to be a reasonable price.

But you should NEVER have paid $125 for a set of 081 castings. Man, they are in every wrecking yard on the continent for very cheap prices. 601s and 416s will also work just fine. If a person just follows the instructions I laid out they will have a very nice set of heads that should provide at least 30 more hp on a 300 hp engine. Just doing what Standard Abrasives recommends with their kit got them 19 hp and they didn't enlarge the intake valves at all.

My port and polishing thread DOES include the cost of larger intake valves and the cost of machining the combustion chambers to accept them. I also included the cost of a variable speed switch and anyone can rent a die grinder for about $30 US a week. The $350-400 cost included all new valves, springs, the WORKS! So much of what you complain is clearly dealt with in the thread. You need to read the whole thing.

PS I don't have any sort of fancy setup for working on heads. Used a WorkMate, bought some carbide cutters and also the Standard Abrasives Deluxe porting kit, which you really don't need anyway. It is all included in the price I quoted

I do agree it is a fairly dirty, not to mention time consuming, job, though. Not something for the kitchen table, as you said

I spent about 20 to 25 hours on my set of 601s.