tpastorok

Car is a 91 Camaro rs 305 tbi, basically stock except someone swapped it to a manual

It has close to 200k miles on it, not sure of the exact number since the odo and speedo were out when i got it

So I have just been having a ton of headaches that mostly, if not solely, relate to electronics and such and I've been having a few people urging me to just rip it all out. But before I decide to do it I need some info and pros and cons. In terms of ability, I'm not the most experienced in working on cars but I've been learning (gotta start somewhere) and have the resources to figure things out, and I think I have the money. I'm not looking to go to crazy and get huge upgrades, but it would be nice to at least gain a little power along with (hopefully) simplicity and reliability. I know that it'll be the most in depth project I've done so far but as long as it's not way out of reach I'm willing to take it on, but are there some big down sides that I'm missing?

jwfirebird

iTrader: (2)

you are not gaining any power, i did it for simplicity, a little weight and the car looks alot better without all that smog crap. the other thing you gain id easy adjustability for mods. its not cheap either, a few things off the top of my head, manifold, carb, all in one dist, adjustable fuel pressure regulator, sometimes you need to do something with the pump, if the ops is working it will run on that but when you take the pcm out you need a way to prime the pump, i recommend a manual switch, then turn it off and let it run on the ops for safety. having the 5spd gets you out of the electronic trans issues. i just keep a gps in mine, it doesnt care what tires, trans, gears etc you have.

tpastorok

Alright, for me to decide to go through with it I need to make sure of two things: 1) can I afford it right now 2) do I have the skill to do it, or at least be able to figure it out without a huge amount of trouble. I I'm going to need to replace the fuel pump that really turns me off to it a lot just because its such a hassle to get to on these cars. But anyway, here's what I have in terms of a parts list thus far:

Intake and carb kit; holley 600 and edelbrock performer intake-----$502.05
http://www.summitracing.com/parts/cmb-03-0125
MSD Street Fire Distributor---------------------------------------$149.95
http://www.summitracing.com/parts/msd-8362
Hypertech Fuel Pressure Regulator--------------------------------$59.97
http://www.summitracing.com/parts/hy...make/chevrolet

Please let me know if any of this won't fit or if I can go cheaper on some stuff, so far this is just based off what summit racing says will fit the car and I know those kinds of searches aren't always best so some real feed back would be great.

jwfirebird

iTrader: (2)

return or bypass style regulator- you hook up the feed and return to it up in the hood area.
http://www.summitracing.com/parts/hl...03bp/overview/
you need to get a gauge too

dist seems good, carb kit seems expensive for what you get.

this is the summit "holley double" its a good setup for performance street, and its on sale with that bowl connector part, alot of times those have the fuel gauge port on it.

http://www.summitracing.com/parts/su...s/applications

then get a performer type manifold for your engine and square bore carb, this is a gen 1 sbc, i have read i think all you need to do is slot out the holes to use one. they have ones that are for 86+ but might be more expensive
http://www.summitracing.com/parts/su...-size/5-7l-350

and you need a made for holley 4150 type drop base air cleaner

http://www.summitracing.com/parts/edl-1223/overview/

jwfirebird

iTrader: (2)

this is just turning bolts not difficult if you take your time. you will need to learn how to tune carbs, this really makes the swap. a improperly tuned car is not even as good as a failing tbi. that one had a book with it too, the sticky here for holley is good too. look at some of the threads tuning on vacuum secondary carbs.

ebay is a good place for jets, and tuning parts, jegs had a store on there and i got each size for 5 bucks shipped.

tpastorok

Thanks jw, that's exactly the type of info I'm looking for. So based on what you said this is what I have now:

Summit Street & Strip 600cfm------------------------------$260
http://www.summitracing.com/parts/sum-m08600vs

Edelbrock Performer Intake---------------------------------$200
http://www.summitracing.com/parts/edl-2104
I'm willing to pay the extra for the one for my year just because of simplicity considering my lack of experience

Edelbrock Air Cleaner---------------------------------------$30
http://www.summitracing.com/parts/edl-1223

Holley Fuel Pressure Regulator------------------------------$73
http://www.summitracing.com/parts/hly-12-803bp

MSD Street Fire HEI Distributor-----------------------------$150
http://www.summitracing.com/parts/msd-8362

How does that look in terms of all the parts I would need? And would I need to do anything in terms of the fuel pump? I know the first response mentioned something about a way to prime it without the ecm I think? Thanks again

ownor

iTrader: (5)

i don't know how hacked up your car or electronics are, but i think for the same amount of time and money you could also make the TBI run right.. that said, this will also depend on the engine mods you have/are anticipating.
also since it seems you aren't familiar with carb tuning, you would need to get to know either system anyways.

jwfirebird

iTrader: (2)

the stock pump is fine, unless it fails for some reason but you are feeding the same engine and if you have a return style regulator it should be fine. the pumps need fuel to keep cool and the other style regulator "dead heads" the pressure and is alot more stress on the regulator. the prime would be finding the pump relay, cut the wire that goes to the pcm, get a regular on/off switch and wire one side to the wire you cut and the other to +12v somewhere convenient. the pcm energizes this wire to control the pump, i think on my car it is by the vacuum booster. dark/green white trace. some people find the ops is bad, because normally you would not know, keep that in mind if the pump doesnt work by itself

you will need a fuel gauge, one of those 10 or 15 psi ones would be good, you need to set it to 5 or 6 psi

i made my oem carb throttle bracket work with a couple bends and another piece of metal to strengthen it, im not sure what you have.

looks like your cooling is separate from the pcm so that should be fine
http://austinthirdgen.org/mkportal/m...ine_wiring.gif

skinny z

You may want to rethink that carb. It's a re-branded (and now discontinued) Holley 4010. It isn't the typical 4150 style and modifications and tuning are sightly different than the norm. Tune up kits are unique as well.
Some parts are interchangeable: jets and the power valve specifically, while other parts are not. The 4010 does not have removable float bowls. The entire top lifts off and the jets lie within the main one piece body. Fuel rails are also specific to the 4010 as the angle and size of the fitting at the carb body are different.
From a daily driver/mild performance point of view it worked well for me. Once I got into more serious carb tuning, I shelved it (and still have it) and moved on a carb based on the 4150.
Still a good bang for the buck but it's something to think about.

jwfirebird

iTrader: (2)

you might need to search local for little adapters and things too, going from stock threads (probably metric) to standard regulator. then you will need a hose to go to the carb. little stuff like that shouldnt be too much but there is always stuff like that you should expect to come up

jwfirebird

iTrader: (2)

i thought it was a "summit" 4150 or 4160, i wouldnt have suggested it otherwise. one of those may be more but i think the befits are worth the money, i got a holley 4150. the 4160 is kind of a decent street carb, the 50 has more tuning capability and is good for more strip use, and has the tuning capability to be good on the street too

skinny z

Depending on the application the 4010 can perform very well. I just didn't want the OP to be surprised when he opened the box. That said, I'm in agreement with you on a 4150 style being the way to go if only for the wealth of parts and information that are available. All of the same carb theory applies to the Summit brand carb but it may be difficult to cipher what's needed one way or the other in terms of tuning advice.
From the look of the picture in the Summit catalog, it appears that the fuel rail adapters are included. The 4010 has the inlet fitting exiting horizontally and an angled adapter is needed to move the fuel rail out of the way of the air cleaner base.

skinny z

I couldn't agree more.

jwfirebird

iTrader: (2)

http://www.ebay.com/itm/HOLLEY-0-1850SA-600-CFM-ALUMINUM-STREET-CARBURETORS-MODEL-4160-MANUAL-CHOKE-/141227508384?pt=Motors_Car_Truck_Parts_Accessories&hash=item20e1d0c2a0&vxp=mtr
http://www.summitracing.com/parts/hly-0-4776s/overview/

any dual inlet carb is gong to need to have one of those connectors and a manual choke is going to need a lever

jwfirebird

iTrader: (2)

http://www.ebay.com/itm/HOLLEY-0-1850SA-600-CFM-ALUMINUM-STREET-CARBURETORS-MODEL-4160-MANUAL-CHOKE-/141227508384?pt=Motors_Car_Truck_Parts_Accessories&hash=item20e1d0c2a0&vxp=mtr
http://www.summitracing.com/parts/hly-0-4776s/overview/

any dual inlet carb is gong to need to have one of those connectors and a manual choke is going to need a lever

skinny z

The 4150 style carb in your last post won't require the angled adapters as the fuel bowl has the angle built in. The 4010 doesn't. That's of minor consequence though. Just another detail to take care of.
At $200 in the difference I can see the temptation of the Summit carb as compared to the Holley.

tpastorok

Thanks for the great info everyone. So on the other hand of my options, what steps would I need to take to get the tbi running close to, if not perfectly? This would probably be a better post for the tbi forums but I'll just see if anyone here knows.

jwfirebird

iTrader: (2)

i dont know much about the tbi, i had a 89 pickup with the tbi 350 for 8 years and all i ever did to it was normal maintenance stuff, ign/fuel pump/oil. took the cat off and the heat riser thing and got 22 mpg on all hwy trips

sootie007

https://www.thirdgen.org/forums/carb...s-305-tbi.html

I just did this ....my thread above , prices , challenges etc .....

Ghettobird52

Why not stick with tbi and with the money you plan on spending going carb, grab ebl flash, an adjustable fpr with a fuel pressure gauge and go from there? you'd prob spend less and gain better mpg with the hp/tq

jwfirebird

iTrader: (2)

your still stuck trying to keep up with 30 year old overcomplicated parts, and the tune is good for one setup, if you want to change anything you have to have it tuned again and again

ownor

iTrader: (5)

jw, i haven't tuned carbs before but actually that's the 30 year old parts overcomplicated or not, i'd say that's subjective on either count. yes you have to adapt the TBI tune (except if you're running MAF TBI) to any changes, but so you have to for a carb either?
besides, ima go and say there's no way you can get the same drivability, fuel consumption and probably power out of the same build with a carb, for anything that sees at least some street duty as well.

Ghettobird52

Agreed

jwfirebird

iTrader: (2)

im not talking about age of design, talking about the physical age of the components on these cars, and the over complication is all the sensors, 30 yr old wires, pcm, 30 year old vacuum lines that you have to keep after to keep it running right.

so comparing a new carb, new hei that requires one wire, i would much rather have that and not have to screw with a computer every time i want to change something on the car.

and a properly tuned carb has the same ability in every way as a tbi setup on the same engine

ownor

iTrader: (5)

ok

sootie007

"So comparing a new carb, new hei that requires one wire, i would much rather have that and not have to screw with a computer every time i want to change something on the car."

Agree 100% on that point - that was the main reason I swapped over from TBI to carb on my 91 vert .

Ghettobird52

I have to disagree with this its not just 'one wire'. what about actually changing the SA curve on that HEI? Time to rebuild the dizzy with new weights & springs. while all i have to do is open up tuner pro and with a couple key strokes its done. This is just ONE example

jwfirebird

iTrader: (2)

the dist "rebuild" requires taking a couple screws out, im sure i could do it before the computer boots one time

Ghettobird52

lol please, couple screws? Doing your SA Curve on those Distributor's are not just couple screws when doing your advance plates as well as your springs, weights & center pieces. Not to consider even GETTING to that! Take off Dist hold down bolt, Take off ALL plugs then unbolt cap& rotor.

Maybe if the tuner was running on windows 95, even then i still doubt you could do all that within a boot up time. Once again this is just ONE example.

jwfirebird

iTrader: (2)

i have a mallory 85, you dont have to take anything off but the cap and rotor, leave the wires on, and its right on top.

onemanarmy41

I probably spended $100 for my 88 k1500 with the 305 in it , just look up my album or txt me, I went with a 2 barrel for economy but yet simple t came from a 79 dodge ramcharger with the 360 engine so I knew it had plenty of cfm then a rebuild kit, I used the original pump with no pressure regulator by installing a Cadillac cts filter that has a return line built in the excess pressure was returned to the tank safely and made my own adapter plate to the tbi intake but ebay has them for about $30 and that was it, simple yet reliable is like the 6th vehicle that I owned that I had done this conversion I still come across customers that own the converson and is all good, good luck and have fun, by the way the truck had a th400 tranny you got to have that or a manual to make it simple

jwfirebird

iTrader: (2)

so the cts filter is a regulator? you ever take a reading of the fuel pressure at the carb?

five7kid

iTrader: (14)

Sorry, but this simply isn't true.

jwfirebird

iTrader: (2)

if you could theoretically directly swap a carb for a tbi with everything else the same, whats the difference? the tbi is a carb body that puts as much fuel as it needs to get the o2 happy. the carb does the same when you tune it properly. im not talking about the newer fancy stuff like mpfi and direct injection, that changes the place the fuel is put in and adds monitors

skinny z

It more the WAY the carb does the job as compared to TBI. We're talking OEM here.
Take a look down the barrels of an appropriatley sized carb and compare it to a TBI. You'll see the obvious differences. It's these differences that make the carb a superior selection in most regards. The only thing you can't do is tune it with a computer. That said, the proper carb with fully tunable circuits can approach the drivabilty of EFI but it's a LOT of work. I'm in the middle of that right now.
The newer self learning throttle body units are a huge step up from the OEM stuff. Those can give a carb a run for their money. It's something I just recommended to my son-in-law who wants to get into the hot rodding game with his mid 90s Chev pickup. He hasn't the capacity to tune a carb and since he'll be staying with the Gen 1 small block format, it seems likely an obvious choice.

five7kid

iTrader: (14)

You can tune a carb all you want, but it won't be able to compensate for altitude changes without more tuning.

TBI will never have fuel bowl slosh issues.

Fuel atomization with carb cannot approach that of an injector.

That's just for starters.