TBIThrottle Body Injection discussion and questions. L03/CFI tech and other performance enhancements.
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Hey guys is it possible to add a procharger to a 1989 305 TBI? OH yeah another question, how can you tell when a camaro is a Z/28 - IROC, or anything else just by looking at it without any emblems, Thanks guys.
Go to Procharger and see what they offer for our 3rd gens. I don't beleive they have a TBI offereing but then again, I only was looking for a TPI setup at the time. In regards to what you car is look at your RPO codes.
They do not offer a TBI system for a 3rd Gen. They do sell one for the TBI pickups though. So long as the truck application years matches you r cars, it should install fine. You will want to make sure the A/C and alternator are on the ocrrect side or you will be hunting down different factory brackets.
The same is also true with Vortech.
HOWEVER, you could spend a few grand less and just get a Whipplecharger for the TBI, have no install headaches, and get pretty much instant full boost that a centrifugal will not give you.
There are lots of things to consider when picking out a blower.
Procharger sells a TBI as well as a carb version. I believe both will work. something tells me the TBI unit is much smaller. you will need to change ECU's and add a 2 bar Map sensor along with a WB02 for good luck.
Whipple has nothing on their site at the moment but they do offer a small block carb and efi setup...plus, whipples just sound badass altogether....haha, my choice if I get one.
Carb=TBI. they both use a 5.175 inch bonnet. I think the only diff is that the early TBI blowers were for daily driven trucks so maybe they did not run as large a unit. I know of no issue other than the fuel injectors(2) will need to be maximum (90 lbs) at high fuel pressure. The issue that develops then is the pulse width is too large at idle but that can be addressed in tune. I am uncertain if a VAFPR will work under boost? VAFPR is used under a non boost setup for high perf TBI. Allows a reasonable pulse width at idle yet provides adequate fueling at WOT. I would like to know what kind of MAP readings would occur at moderate boost at WOT.
I'm surprised nobody has really ever tried the Wynjammer setup as far as I know. It looks to be pretty slick, self contained, provides decent boost, made for TBI, and he said he'd sell it for $1650 without the chip. Sounds like a pretty good deal to me and super easy to install.
Procharger sells a TBI as well as a carb version. I believe both will work. something tells me the TBI unit is much smaller. you will need to change ECU's and add a 2 bar Map sensor along with a WB02 for good luck.
Quote:
Originally Posted by Ronny
Carb=TBI. they both use a 5.175 inch bonnet. I think the only diff is that the early TBI blowers were for daily driven trucks so maybe they did not run as large a unit. I know of no issue other than the fuel injectors(2) will need to be maximum (90 lbs) at high fuel pressure. The issue that develops then is the pulse width is too large at idle but that can be addressed in tune. I am uncertain if a VAFPR will work under boost? VAFPR is used under a non boost setup for high perf TBI. Allows a reasonable pulse width at idle yet provides adequate fueling at WOT. I would like to know what kind of MAP readings would occur at moderate boost at WOT.
The Procharger is made to work without having to do any of that. It uses a FMU to take care of the fueling needs with the stock injectors. 90 lb injectors scream overboard for 10 lbs of boost. They didn't upgrade anything on the extended cab they bolted the system onto that wasn't included in the system.
The truck TBI is the same as an F-body TPI in size. If you have a BB TBI, just purchase a BB TBI bonnet from ATI.
I'm surprised nobody has really ever tried the Wynjammer setup as far as I know. It looks to be pretty slick, self contained, provides decent boost, made for TBI, and he said he'd sell it for $1650 without the chip. Sounds like a pretty good deal to me and super easy to install.
I have it on my 92 454SS pickup. It knocked a second off of my ET.
I have it on my 92 454SS pickup. It knocked a second off of my ET.
A full second huh? That's great. They sure looked good to me, sounds like they perform well too, I just wish I had the cash to throw one on ha. How much boost is it pushing?
A full second huh? That's great. They sure looked good to me, sounds like they perform well too, I just wish I had the cash to throw one on ha. How much boost is it pushing?
I got a great deal on mine
Its advertised as 6 lbs; I haven't installed a boost gauge yet.
__________________ 90 454SS; TBI 496. Best to date: 12.42 @107, 1.63 60 ft.
the gains of a supercharger(and turbos) are fairly straightforward.
1 bar = 15(actually 14.7, but who's counting) psi = one atmosphere = 100% stock horsepower.
so if you're running at 6 psi, and you had say a stock 170 hp l03(i realize the truck doesn't have this, making an example) you should be making ~238hp(and every psi up would gain about 12hp), assuming your injection setup is capable of providing the fuel. any modifications done to the engine itself would see exponential gains relative to the psi baseline of your setup(in other words a 30hp engine gain would be a 42hp to a 6psi setup, or 60hp to a 15psi setup).
there are variables, such as tuning(many turbo users use exhaust temps as a gauge, as it seems to be more accurate than straight up prom tuning do to the inconsistancy of the turbo itself) and things like intercoolers, which can adjust the equation by 10-15% in either direction depending on size and placement(and again, whether your fuel setup can handle it). also the actual type of supercharger can make a difference, but that's more in the intracacies of how it builds up the psi than total power made. then of course there's drivetrain loss, but that's a whole different monster.
it's not an exact science, but I've found it to be quite accurate.
btw, the truck stock made 255hp and 405 lbs of torque according to
the gains of a supercharger(and turbos) are fairly straightforward.
1 bar = 15(actually 14.7, but who's counting) psi = one atmosphere = 100% stock horsepower.
so if you're running at 6 psi, and you had say a stock 170 hp l03(i realize the truck doesn't have this, making an example) you should be making ~238hp(and every psi up would gain about 12hp), assuming your injection setup is capable of providing the fuel. any modifications done to the engine itself would see exponential gains relative to the psi baseline of your setup(in other words a 30hp engine gain would be a 42hp to a 6psi setup, or 60hp to a 15psi setup).
Wait, so you're saying that 6psi will make my 305 TBI gain that much brake horsepower? How much boost can the stock TBI heads/block take? In otherwords what is the safest boost I can run with everyday?
I've decided I'm going to rebuild my 305 and just add a supercharger--so this info is rather important to me.
yes, you should make that much with a properly tuned engine running at 6 psi.
and I can't give you any kind of promise or guarantee, but 6 psi is pretty standard for a supercharger, and it's not too much power for the engine to handle, so a rebuilt engine should have little to no trouble with it.
the main questions are whether or not you'll be going carb to run the supercharger, if you are then you've gotta do a little work to make sure you can get enough fuel pumped in, wheras if you decide to stay with tbi it's a whole other monster.
it's not impossible, but you'll want to get into tuning right now if you intend to do so.
I had been debating it for a year about supercharging or not. I had tried an m90 and unless its put after the tb not before, its harder to get working even at idle it would make boost pushing air/fuel out around the gaskets on the tbi even with a blow off valve there was no way to regulate the flow and it wasn’t even making 3psi the engine was to big even as a 305 besides the fact of hood clearance and lining up pulleys. Maybe its different on MPFI.
I stumbled on the wynjammer site and it looked liked a good kit s10 guys rave about it on their forums. He had a few with bad bearings back in '05 but it was a vendor problem and was fixed.
I sold the m90 stuff and bought his kit without the chip it was one of his last old kits hes working on a new tbi kit. like bronyraur I was surprised too that no one has really tried the kit most of the questions about the charger were dead ends. For a small company it was a very nice kit the brackets are powder coated and the instructions were good. I did have to redrill a hole and mount the main bracket over a little since this wasn’t a truck tbi, but wasn’t to hard compared to a whole custom mounted system. I put the kit on about a month ago but haven’t had much time to tune it, it goes lean after 3000rpm wot but its been fine with everyday driving. It does make around 6psi, is semi loud when you first start but it becomes a slight whistle at idle when you get on it it has a whoosh whine kinda like a turbo its a tuff call I kinda miss the sound of the eaton.
You can get it to work with tbi but your gonna need a lot of tuning and bigger injectors which Im waiting for, 350 injectors don’t cut it.
So how much does that whole wynjammer cost? Looks like a pretty neat setup! Not usually a big fan of boost, but that is really cool. I like the way it runs off the alternator pulley and not having to re-do the whole serpentine system.
__________________ -Adam
1990 Firebird Formula
Bone Stock 305TBI, T5 tranny, 62k Origional
UMI subframe Connectors
Was around $1600 with shipping. You can get it with the chip but thats $100 more but I didn't need it. His prices are goin up so Im glad I got the old kit. I had to use my carb hat his is to tall and for a truck also used blowoff valve from my m90 project. At $2000-up for a carb kit and $4000-up for a new tpi kit which u have to modify the intake to work with tbi and run oil lines, it made more sense to try this kit. go to http://www.wynjammer.com/ hes a cool guy he helped design a few kits for paxton, I also read somewhere he worked with shelby and helped fit the 4 valve 4.6 into some ford cars.
I had been debating it for a year about supercharging or not. I had tried an m90 and unless its put after the tb not before, its harder to get working even at idle it would make boost pushing air/fuel out around the gaskets on the tbi even with a blow off valve there was no way to regulate the flow and it wasn’t even making 3psi the engine was to big even as a 305 besides the fact of hood clearance and lining up pulleys. Maybe its different on MPFI.
I stumbled on the wynjammer site and it looked liked a good kit s10 guys rave about it on their forums. He had a few with bad bearings back in '05 but it was a vendor problem and was fixed.
I sold the m90 stuff and bought his kit without the chip it was one of his last old kits hes working on a new tbi kit. like bronyraur I was surprised too that no one has really tried the kit most of the questions about the charger were dead ends. For a small company it was a very nice kit the brackets are powder coated and the instructions were good. I did have to redrill a hole and mount the main bracket over a little since this wasn’t a truck tbi, but wasn’t to hard compared to a whole custom mounted system. I put the kit on about a month ago but haven’t had much time to tune it, it goes lean after 3000rpm wot but its been fine with everyday driving. It does make around 6psi, is semi loud when you first start but it becomes a slight whistle at idle when you get on it it has a whoosh whine kinda like a turbo its a tuff call I kinda miss the sound of the eaton.
You can get it to work with tbi but your gonna need a lot of tuning and bigger injectors which Im waiting for, 350 injectors don’t cut it.
you'd need 42psi from the stock(I believe these are the numbers) 55# injectors to handle the supercharger.
you'd need 27.5psi from a pair of 68# injectors, which I believe came off of the 350's.
I based my formula entirely on the assumption that
a. from only the information on your side tab, you have a 305 with a zz4 cam, which tuned could put out a relative 250hp(again, with exhaust and tuning).
b. added 6 psi(for the supercharger) which made about 350hp total(6/14.7=40% increase of base horsepower).
I'd suggest you read that sticky if for no other reason than to make a more accurate formula based off of your deeper understanding of what you've done to the engine and what it's true power potential is, but also for the information on how to change the psi of your fuel pump so that you can make that kind of power without using huge(and far rarer) injectors to do it.
by the way, the point of this was that I think you actually can get away with 350 injectors if you're willing to do a bit more extensive tuning, and possibly change your fuel pump.
Last edited by FreeLoader; 03-03-2008 at 01:29 AM.
the gains of a supercharger(and turbos) are fairly straightforward.
1 bar = 15(actually 14.7, but who's counting) psi = one atmosphere = 100% stock horsepower.
ITs not that easy, the final pressure ratio is what determines the power gains, You have to have an effeciancy map, and map the effeciency of the supercharger to where it corresponds to peak power and peak torque (peak torque = highest VE the engine makes). Realistly, most centrafigal superchargers are probably in the 65%-70% effeciency range, so you at 6psi, instead of having a 1.4 pressure ration of the 6psi @ 70% effeciency, you have a 1.285 pressure ratio. (give or take, I didn't do all the math, really you convert inlet air temps to kelven, calculate the final temp in kelven based on effeciecy, and adjust the pressure ratio that way. I was lazy tonight).
So with no intercooler, a 170hp engine, with 6psi of boost, at 70% effeciency, will really make 218hp.
But like everyone else has said, the real key is in tuning, with EBL it should be fairly straight forward to tune. I plan to run a boosted setup here one of these day's, I'll make sure to document all the tuning needed.
for 2 grand would it be better to run duel turbos or this ? doesn't seem like this could make a lot of boost unless you can add a bigger pulley. 6psi is nice, but its not no 12-30 which you could obtain for the same price. Not to mention how much HP draw is this charger draining from being belt driven off the alternator ?
All joking aside. it depends on what you want. Some people want the linier powerband of superchargers, some want the higher effeciancy of turbo's, some don't want to deal with fabrication of turbo's, etc.
Quote:
6psi is nice, but its not no 12-30
You would be building a darn serious motor if you plan on running 30psi. It doesn't matter how much boost you CAN make (a supercharger that is large enough, with the right pulley, can make that no problem).
Quote:
Not to mention how much HP draw is this charger draining from being belt driven off the alternator ?
Superchargers are driven by the crank. Its a 50/50 toss up with turbo's, a turbo is a big restriction in the exaust, you lose power either way. With a centrifugal style compressor your thermal effeciancy should be about the same as a turbo, since the compressors are similar. One is driven by the crank, one is driven by the exaust. It is probably a toss up between the two for peak power, the turbo will build full boost quicker though. Like I said, toss-ups.
For the average Joe on the forums here though, a bolt in supercharger is much easier. Not everyone here can fabricate headers. And there are pretty limited header suppliers. Cost wise, it can wash either way too. With turbo's, you have supply wastegates, etc. Without really looking for good used parts, I would be hard pressed to build a good turbo setup for under 2k. it would be VERY easy to spend well over 2k, and a pair of good turbos.
its pretty damn complete kit, id still get a few extra's like a cam, and full turbo exhaust, but all this for a grand ? and it includes all the pipes ?
too good to be true ?
its pretty damn complete kit, id still get a few extra's like a cam, and full turbo exhaust, but all this for a grand ? and it includes all the pipes ?
too good to be true ?
Thats already been brought up before. Personally id stay away from any ebay stuff, and stick to name brand.
think it would be fun to boost a mid modified 305, see what kinda hp you can get outa it. For the price its still a decent deal, Besides, i break it, gives me a reason to tell the wife i need a new motor, *cough* 383
ok this is a stupid question, what happends to your vacuum after a supercharger? lol do your lines "pop" off? heater stuff not work? im just trying to lean so dont be too mean
__________________ just to be clear, this car is a rendering.
current project:88rs/iroc clone. Pro touring ls1/t56
Good question. I have never heard it asked. I will suggest when you are on throttle Neg vac or MAP >100++ you are not on brakes. When you need to whoa Nelly you are off throttle and with closed throttle plate then VAC is highMAP low so a non issue? I think that is whn a blowoff valve comes into play as blower is still spinning at high rpms yet throttle closed.
lol so was that an answer or another quesion? lol some of the terms got me>100? ok so then driving down the road at 8psi max at full throttle they would not pop off? or 4ish? just driving around everything else would work? somebody give a full explination?
I believe that there is a "vacuum canister" in the car from the factory. It stores vacuum for a short while so that if you go WOT your accs. still function. And the power brake booster also stores enough vacuum for 1-2 good stops. If you ever pump the pedal a few times after shutting off the car you will find that out.
The other option is an aftermarket belt-driven vacuum pump. These come factory on most diesel vehicles, but I believe summit sells some that work on cars like these. People tend to use them when running a radical cam with low idle vacuum.
__________________ -Adam
1990 Firebird Formula
Bone Stock 305TBI, T5 tranny, 62k Origional
UMI subframe Connectors
Maybe someone that runs a 2 bar MAP sensor can answer that. From what I read when the MAP is in excess of 100, 100 being atmospheric pressure(no vac), a 2 bar map sensor is needed to register positive pressure >100 MAP. Maybe someone will chime in as to what they actually read >100. I cant believe it is all that excessive to burst/blow off lines. My MAP sensor reads VAC just below the throttle blades. My VAFPR reads off the manifold where the vac line to brakes exists. I can imagine enough boost-positive pressure to blow off those lines as well as others.
Would anyone supply me with a bolt on supercharger, not one of them superchargers that look like turbochargers? I'm looking for places to buy from, want a satin if possible.
I have a 1989 Camaro RS 5.0 TBI so if anyone could supply me links to websites I could order a supercharger for my camaro, that would be great.
slow_90firebird your thinking of the purge canister its main purpose is for emissions its traps excess vapors from the manifold, fuel tank and lines when the engine is off, when the engine is running all those vapors are sucked back in to be burned off.
if the vac. line connections are solid and tight as they should be and no cracks in the hoses they will be fine they may slowly get pushed off but they shouldnt just pop off, you may want to try some zip ties or clamps to hold them on if that were to happen.
the nice thing is gm put check valves for the heater controls and brake booster, the valve only opens under vacumm so under boost the valve closes so no air is forced into the booster.
remember you dont see boost 24-7 only under WOT or heavy acceleration. you still create vacumm as the blades close, the throttle blades control how the air flows, also some superchargers go after the throttle body or under it so when you close the throttle the air is for the most part cut off from the supercharger so it spins with almost no air going through it. for the superchargers that look like turbos they do not make much boost at a slow speed or idle so they can go before the throttle body and push air through it not suck air through it.
The blow off valve is for WOT situations when your in boost and shift gears or let off the gas quickly.. when those throttle blades are shut the air cant go anywhere and you can get a bad spike in pressure, I think thats where you get the idea of lines blowing off. the BOV helps prevent that by venting the excess pressure which can cause damage to the supercharger.
anything over 100 kpa is in boost compaired to atmospheric the map sensor stops reading a little after 100, i think 104 then thats it any boost you make the sensor will say 104 no matter what.. so the ECM doesnt know any better or what to do after 100.
sadly no one makes a direct bolt on kit for our tbi cars you might get a tpi kit to work with some intake piping or use a truck tbi kit but may need different brackets or a higher hood. you could custom make something. There are some carb style blowers that say they would work with serpentine belt but again you might need a different hood. anything you do will probably be custom.
sorry for the long post hope that helps answer some questions.
I'm surprised nobody has really ever tried the Wynjammer setup as far as I know. It looks to be pretty slick, self contained, provides decent boost, made for TBI, and he said he'd sell it for $1650 without the chip. Sounds like a pretty good deal to me and super easy to install.
Seems rather pointless to me as you can buy a used 350TPI with 230HP stock and computer and wiring and everything for under $1500. I don't see a point. I am not trying to rag or anything, but isn't it more reasonable to just get a 350?
__________________
88 Firebird Formula 350 89k miles 13.1 @ 105... 1.8 60ft W/ low compression in 2 cylinders and smaller cam... Superram- Trickflow AL Heads- 268XFI *3290 LBS*
To Do List: Tranny (#3), Rearend (#3), Paint... Then DONE!!!
Seems rather pointless to me as you can buy a used 350TPI with 230HP stock and computer and wiring and everything for under $1500. I don't see a point. I am not trying to rag or anything, but isn't it more reasonable to just get a 350?
hay bullydawg new to this site anybody running thi tbi supercharger
Seems rather pointless to me as you can buy a used 350TPI with 230HP stock and computer and wiring and everything for under $1500. I don't see a point. I am not trying to rag or anything, but isn't it more reasonable to just get a 350?
My reasons for staying 305TBI
1.) Everyone with a 350 says go 350
2.) Everyone with a CARB says go CARB
3.) Everyone with TPI says go TPI
4.) Everyone with TBI is told all the above
5.) I already have a motor that runs, why buy another. Ill finish this one first.
It is more reasonable to buy a 350, but you dont get that my 305 just beat your 350 chance once you do that. Which one day down the road I will be doing.
Not to mention suspension, transmission and rear end are definitely getting done before any real major motor mods. No reason in having a badass motor only to never put it down to the ground.
So its preference/opinion really. I like my 305, BECAUSE its not a 350.
just to be clear, this car is a rendering.
