and how did it go post some pic's of your setup if you got them

 

It's a pretty simple swap. I think there is a tech article on this site about it if your intrested in whats involved in it.

 

i just put a bulit vortec moter in my car and im wanting to go carb so i need help on doing it right. what do you have done to your car and how fast is it. any tip would be great






89 camaro rs 350 bored 30 over
vortec heads
tpi roller cam

 

Buy the way your car looks great!!!!!!!!!!!!!!!!!!!!!
:rockon:

 

I have done it and am SO!!!!!!!!! glad I did. Drop me a e-mail with any questions.



Brian

 

What are the advantages of doing this swap??????

 

advantegous of going to a carb

EVERYTHING!!!

 

.

 

http://us.f1.yahoofs.com/users/3f282...yMOr9A2G4XbqfN

 

What are your all's suggestions for a carb and manifold to be used on a stock 305? And would I have to change distributors at the same time? I am going to get the tech article as soon as I finish this post to read more about the swap.

David

 

Stock 305,go with a Weiand Stealth intake and a 600 Holley Vaccum sec. Yes you will have to swap distributors. Put in a HEI and you'll be good to go.

 

I used a holley S/A and a performer RPM and its pretty good. I did lose a little torque down low but what you gain over 3000 rpm is huge. I also used the proform HEI from Jegs. Use your coil wires for your HEI connections + & - and for your tach. You will be fine. I made a good bit from my TBI stuff on Ebay to pay back the swap. You may have to make your own Throttle bracket and TV holder but if you use the old one you can cut and drill to make it look and work nicely.



Brian

 

Do you have a picture of your setup so I can see what it looks like?

 

I ended up up getting the holley bracket and I would recomend using it if you have the extra cash. I can send you a file of my current setup if you like.




Brian

 

That would be great if you could. My e-mail address is dhjr@insightbb.com

Thanks,

David

 

Ok, So what are the dis-advantages of going carb?? (There has to be some?)

 

Ok, So what are the dis-advantages of going carb?? (There has to be some?)


You have to do work to do the swap.

 

You are going to lose a little MPG and in cold weather fuel injection seems to be better however there are some carb guys who can make even those go away.



Brian

 

Any performence gains from the swap or is it simply made to get a better platform for future mods?

Sorry for all the questions.............Just trying to get as much info on the swap as possible so i can start planning/looking for parts...

 

You will still have to go to autozone or pep boys because something always happens

eg: no frikin teflon tape for the dual inlet fuel line

Here is a list that i would use:

MSD HEI Kit (6A Box, Blaster 2 coil, New dust cover)
Accel 8mm Plug wires. Get the uncut set and cut them custom for yourself. i did and his is when I knew **** about cars.
New Spark Plugs: AC Delco makes some good ones for 45 bucks a set.

Holley 670 S/A Might seem like overkill, but if you plan on adding some good mods it will be better down the road
Dual inlet fuel line

I will be doing away with my edel performer intake in about a month. Let me know if you want ti because I'll give it to you if you pay shipping.

Make sure you have all the tools, and teflon tape for the fuel lines

.5 in wooden carb spacer...acts like a gasket and helps keep heat away from the carb.

I know I messed something...guys help me out

 

It's mine.......You got a PM

 

careful how much psi you are running at the carb. I'm not sure on the TBIs but if it's over 6 psi you will need to regulate. And if plan on scrapping the stock pump and getting an inline, don't get one of the holley's for normal street driving.

 

Your going to need to get a three port fuel pressure regulator if youplan on using the stock intake fuel pump. There's a line from the tank that goes into it, another line that runs from the regulator to the carb, and finally a return line so that the fuel will go back to the tank and no head up at the carb. you'll need an intake that is for 87 up heads or you can take an old style intake to a machine shop and they can hog out the two inside holes on each side to allow for the different bolt angle on the head. Most importantly you'll need a HEI distributor with the coil in the cap. This is very easy to hook up all you need to do is take the red or pink wire from your stock coil connection and plug it into the batt plug on the cap then use the white wire and plug it into the tach plug on the cap of the new distributor. On my car i had to hot wire the fuel pump to stay on constantly and to do that you'll need to locate the fuel pump relay on the firewall on the other side of the brake booster. there is two relays the one closest to the booster is the one for the fuel pump and the wire you need to hook up is the small green one you need to find a 12 volt source that is hot when you turn the key on and splice it into that wire, then the pump will stay on when you turn the key on. also your electric fan will need to wired to a toggle switch b/c without the ecm it won;t come on automatically. other than that its just nuts and bolts.

 

expect between 10-15 MPG. 15 on a good day with proper vacuum advance and decent divability components i.e. no tunnel rams folks.

10 MPG on a 350 with mild cam, higher than stock stall/gear, heavy foot, mechanical distributor without vacuum advance etc...

3-5 MPG with that tunnel ram boiiie. if your lucky.

 

i am very glad i went with carb i was in the tbi stuff and was using a holley tbi and a custom chip and just really could not get it right. did not have much top end anyware to compare to what i have with the carb i have now and the carb is MUCH smoother threw the rpm then the tbi. The throttle body injection also had lots better throttle responce and could get me over 20 mpg. gettign a right chip helps also, but i did not have the best out there so that could have been one of my problems but its just so much easyer without a computer. seems like every one that was pro tbi when i had my tbi now has a carb

 

Carb = easier for the majority to tune because there are less variables to mess with. TBI = easier on the pocket (daily all year round driver) but a PITA because there are so many things to take into consideration. I always recommend people going to carb if they don't drive it frequently and just want it to run great at the track. As far as consistency is concerned, TBI bracket racing is where it's at. 2 of the 4 guys at E-town's trophy marathon were TBI and the winner was TBI!
Big problems with fuel delivery and TBI the further you rev but like Brian said, TBI is EFI and throttle responce and traffic behavior is a blessing.
BTW, my time is in my sig with TBI and a stock ANLU (cop car) eprom and since then I've added a 2800 stall converter (still lockup). With 3.73's and the auto I still managed to get 24mpg on the 540mile drive from NJ to Ohio. That's going through the mountain ranges in PA , I love the cost effectiveness of TBI BUT I hate being one of the few still using it. It's a Time issue when it comes to WOT performance.
Definatly try a carb cause like I said, if you're the majority which doesn't have much Time or interest in EFI, you'll enjoy your car more.

 

Everyday I fire the car up, I am glad I switched. THe power the engine makes for what I spent, compared to what a properly set up TPI would have cost to run the same, is what made me do it. Here is a pic I took today:

 

Here is another:

 

Hey Josh how did you go about mounting the alternator down there??? Thats a killer setup...did youjust cut the AC part of the bracket off? I have nothing there so maybe i could do that.

When swapping in carb what would i have to do to get rid of the wiring harness? like how would i run new battery lines and wire the alternator...does the engine wiring harness have anything to do with the lights or anything?

 

john, Is that setup under a stock hood? Also did you change from TPI since I see the duel filter setup?

 

With my current setup, minus the cam/intake I got 18-20 mpg. After adding the cam/intake I seem to get about 16mpg or so.
This is with a NON LU TC too.

 

this is what my regulator looks like. if you need the part numbers for the AN fittings to hook up to your exsisting hard lines let me know.

 

Nice setup. Is that the return line hooked to the bottom, or is the the feed line. Also did you tie into the return line at the factory place?

 

the feed line is at the bottom. the reason i didnt use the exsisting factory hard line is beacause i put dual exhaust on my car, and the feed line ran less than 2 inches from my exhaust pipe. so with fear of burning me and my car down, i replaced the factroy feed line with braided and re routed it. you can hook into the factory line where there is a female end. ie, fuel filter, and end of the high pressure rubber lines that hook to the hard lines, you can see it in the pic barely. you have to use a 16mm 1.5 to AN fitting(for the feed line)and 14mm 1.5(for the return line), they have them in 6 or 8 AN. then from that you can run braided to where you want. and even though with a TBI pump the preussre dead heads at about 17 PSI, i wouldnt trust normal rubber fuel hose. i guess you could use the high pressure fuel injection line but I felt safter with braided. I have about 200 bucks in running the braided fuel line, thats with the 20ft of 6AN hose, and alot of fittings. thats not including the regulator or the fuel pressure gauge, or the new aeroquip dual feed line. if you use the exisiting hard lines and high pressure hose it shouldnt be that much. all you will need is the adapter fittings that goes into the rubber hoses, the fittings that go into your regulator, a coupler or a female/female(whoa baby!!)hose end or something to hook the lines to the regulator, then a line that goes to the carb, and a fuel pressure gauge. hope this helps. need anything else let me know.

 

hey johnsjj2,
that looks very clean. how/what did u take off the firewall over where the ac would go. i want to get rid of all my emissions crap and everything cuz its just laying there with no where to go but i dont know what to pull or anything. i dont know jack about this cleaning thing.

 

liljay, I will be changing from TPI to carb, so I will have a lot of pressure on the lines using the stock pump. So I definatly want to use a return line. Thanks for the info.

 

I think you guys have way to much time on your hands, but none theless my 305 gets about 18 miles to the gallon after tune up

 

bluegrass. if you are going from TPI, my opinion is either get a really good regulator, or what I would do is put a TBI pump in the tank. the reason I say that is the TPI pump pressure is around 35-45PSI and the TBI pump is 7-15PSI. If you use the TPI pump, you might experience fuel pressure creep because there is so much fuel hitting the regulator it might have a hard time sending what it doesnt need through the return line and in result your fuel pressure might creep up. there are a few tech articles on this, and one guy who swapped from TPI said he doesnt like it and has had problems. Personally I think its because of the high pressure TPI pump. With the TBI pump, as mentioned the pressure is only 7-13PSI, and that is going to be alot easier for the regulator to handle. Your carb will still have enough fuel, but the regulator wont be getting hammered. Like I said, this is just my opinion. I swapped my V6EFI pump out for a TBI pump and have no problems with it.

Yes i used the factory return line(i might have mentioned this earlier) off the regulator, which had 3/8 npt female, i used a 3/8npt to 6AN male, then used a 6AN-6AN female/female coupler, then went to the factory return line that I used a 14mm 1.5-6AN male fitting. Its several fittings, but they dont make a 14mm 1.5- 6AN female fitting so thats what I had to do.

Jason

 

TBI305CAMARO,
For the alternator, I took off the whole bracket, and mounted the alternator using the top bolt hole that goes into the head. My alternator is not set up for a 91 Camaro, it is set up for a 91 Cutlass. Long story, but the only difference is the 2 mounting points are swapped. The long hole, and the short tab are opposite what was normal for a Camaro. THis shouldn't cause problems as Jester did this also with the correct alternator. Okay, I then marked where to drill a new hole for the bottom mounting hole. Drilled the hole, and tightened a nut against the alternator to hold it flush to the factory bracket. Where the AC compressor was, I marked a line and yes, just cut it off with a cutoff wheel. Make sure you leave enough material around the alternator though for strength. The wiring harness for the lights is separate from the engine harness. THat should not be a problem. I took out the whole harness from the ECM to the fuse panel. The only wires I left were to the starter, dist., and alternator. I just extended the wires to move the alternator over to the pass. side. As far as the battery, the only wires I added were from the battery to the relays for my fans and fuel pump. I did keep the one(s) that went from the battery to the fuse panel. You will need those.

bluegrassz,
Yes that is under the stock hood, but I had to cut off 2 of the studs for the hood buldges to clear the air cleaner. I am in the middle of grafting in a cowl induction now so the turbo piping to the carb will fit at a later date.

spartyon,
Below is a pic of the engine bay after the swap, before I removed everything. I just started taking stuff off. The original idea was to make a more strip car than anything, so the AC, and heat were of no concern to me. There are a bunch of sheet metal screws that hold the fiberglass AC/Heter plenum on. Those have to come out, and there are 3 I think under the carpet on the pass side that need removed. You will be left with 2 holes, the round one from the blower motor, and a rectanglular (kind of) one under the heater core. I made plates to block both of those off.

 

Well wouldnt taking out the wiring harness also take the alternator hookup and battery hookups with it? Looks to me like the alternator and battery connections are part of the wiring harness. Could I maybe put a one wire alternator in its place? one with a voltage reg so it doesnt have to be connected to the ECM.

 

Thanks for the info guys!

 

My oh my... This is a great post. I am in the process of picking up a rebuilt 355 for my 1991 project RS. This is helping a lot just reading this information. Them pics above of the carb swap into a 3rd gen....well.... I LOVE EM! Carbs are so raw and power producing that you just CANNOT go wrong with doing a swap like this. I am buying either a ZZ4 (355HP) or a rebuilt 355 that this guy built for his 67 malibu and ran a best of 10.70. This motor is crazy sick and should be able to put my camaro in the low 10's. With a 4000 RPM stall and 4:10 gears to match it... WOW! Sick power coming from TBI to carb...

 

John, wheres your computer located? Stock computer?

 

I did it and all I did was to remove the wires and harnesses that I did not need to clean it up a bit. It is a little more painful but it will keep you from removing things you need.



Brian

 

Oh let me clarify what I said about MPG. You CAN get good MPG on a carb setup, but there are a few stipulations to THAT.
Flat out #1: Even with stock (2.73) gearing, An overdrive transmission(w/lockup) will make a HUGE difference in MPG. And if you have low gearing (3.73+), it will make an even BIGGER difference.
Using a non-overdrive tranny (Th350, 2400 Stall) with stock (2.73) gearing on a 420~ horsepower performer RPM packaged 355 engine will give you roughly 10-13 MPG. This is MY Experience, and I have tuned the living Frick outa this engine. I started at 5 MPG to give you an idea.
#2: Vacuum advance is where its at on the highway. more cruising power, less throttle opening.
#3: (holley only) Proper power valve tuning is a MUST! without proper power valves, you simply cannot expect good fuel economy and good power.
#4: Any engine that makes good high RPM power (5-6K rpm range - 380-420 HP~ range) is going to have (hopefully!) a decent cam/head/intake combo. This usually encompanies (hopefully!) better gearing and higher stall. Im sorry city-drivers, but better gearing and higher stall (even with lockup) are just NOT conducive to fuel economy! Combine this with the fact the engine has to burn more fuel at lower rpms to make the same power as a stock head/cammed/intaked engine (due generally to pis$ poor fuel vaporazation, low vacuum, and much less low end torque) and you get a very poor fuel economy!

Hey, what do you want? power or fuel economy? You can have both, but then were talking about $4,500 Forced induction setups and $9,000 engine setups... plus the cost of a strong O/D Tranny and a good rear end! Sure with a few ten-thousands we can all have 650 RWHP, 1.5 60' times and get 26 MPG on the highway. But most of us dont have that... well maybe YOU guys do, but I certainly don't!

 

I am posting these as reference for future searches.

 

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