Is the 88 and newer truck 350 tbi intake a good upgrade over the fact. 305 unit on a 91? Are they as good as or comparable to the aftermarket units?

 

No, they both are terrible. Get aftermarket carb manifold w/adapter plate...

 

trucks got the same intake as cars

there is a better intake however (which my car happened to have stock) that has a taller plenum area, (like almost an inch i think) last three digits of the casting number are 182 if you want it its yours for 15 bux you pay shipping

but ill agree with fast broker, that a carb intake is best

 

Pablo,

I have a holley Strip Dominator manifold lieng around. Do you think it may work w/214/224 cam??? Low end would suck, I know, but I'm going for the visual, here. I have not yet nailed down the engine combo I want to use for when I start burning chips...

 

I dont think low end would suck

Remember, most of the reason why carbed motors lose low end with a single plane is because of the decreased vacuum signal to the venturi makes for some pretty crappy fuel atomization. TBI doesnt suffer from that

As such thats what I chose for my motor, Im running an Edelbrock Torker II single plane and i have a 214/224 .5 lift cam in my 305 and it runs great, the low end is fantastic.

Since you said you were the type of guy to swap out cams on the weekend just for the heck of it, i would do the manifold and step up to a 224/234. Of course that will need some custom chip work. If not, Id say, heck try the manifold out, see what it does for your times. I think single planes are important for TBI being that the actual throttle body doesnt flow all that much (im still running the stock unit on mine, and its still choked, but the car peaks around 5500 and pulls to 6k hard)

so imho try it out, the pump shot might be a little lean though

 

I'm gonna do it, man! Not sure if I'll go with the 224/234, though. That's be a litle much. I'll have to fix pump shot with the chip...

I'm still looking for those 65lb injectors... Noone has any to give up. Know anyone who would swap for my 55's??? I wish NewYorker would/could part with hers 65's as it sounds like she can't use them... Oh, well. Think I should call/email/post her about it? I don't want her to get mad...

Also, could just buy 454 Rochester TBI from boeyard and go with that, right??? This might be a better platform for what I wanna do, anyway...

C-ya + thx

 

Hey, I have been looking for a TORKER with EGR but i haven't found one yet. Does Eldelbrock make one?


------------------
1988 Camaro Sport Coupe305TBI-4spdAOD-2.73open in "bought stock" condition. That'll change if it stays around here much longer

 

No

but i believe the street dominator has egr and there is a weiand single plane with egr aswell

 

post 2x

[This message has been edited by Ramsey (edited September 20, 2000).]

 

Fastbroker...

I hate to use the message board for classifieds stuff; but I keep seeing you asking for 65 #/hr injectors. I have for sale a GM injector pod with matched 61 #/hr GM injectors that have been flowed by TurboCity. The inj pod already has an afpr installed also. With moderate fp (15.5 psi) these injectors were supporting 255 hp on my small block. You can email me offline if you are interested.

Pablo... I don't believe the cars and trucks necessarily got the same intake manifolds. I have checked my '94 truck 5.7L manifold casting number against a '92 RS 5.0L manifold and it was different. If you have any resources for more information of this type, please let me know. The truck manifold I mention was used on the above described engine also, and I don't think it sucked. I have changed to a port matched Edelbrock Performer and noticed some, but not a tremendous amount of difference (not been back to the dyno or the track yet).

[This message has been edited by Ramsey (edited September 20, 2000).]

 

255 hp is not enough for me, man. 300 MINIMUM! That's why I want at least 65's. I REALLY want a 454 Truck Rochester 2" 2bbl but am having serious trouble finding one. I could use the 65's on my existing setup unitl I find the big 2bbl. Gonna use my Strip Dominator manifold and buy the PROM burning equip and burn chips 'til I am happy, too.

How much, by the way? (sorry about the Classified thing, I cannot email anyone about non-work related items. It's an SEC thing with Stock Brokers...)

[This message has been edited by FastBroker (edited September 20, 2000).]

 

I'm sorry I was unclear. At 15 psi the injectors were supporting that much power. At higher pressures (and GM injectors have run reliably at 50+psi) the inj will support more power. An increase of 4 #/hr or a 6% increase in flow won't give you 45 or 17.6% more horsepower at the same pressure. Regardless if you run 61's or 65's you will have to increase your pressure significantly. Not necessarily 17% more pressure either,as flow is not linear with pressure in this type of system. AFAIR the only 65 #/hr injectors I have heard of are Chrysler based Holley injectors. When most people refer to a GM 65 #/hr inj they are actually dealing with a 61 #/hr.

Oh, I forgot... the price for the inj pod w/ inj and afpr is $150. However, I have a promise to buy from another individual. If that falls through I can let you know.

[This message has been edited by Ramsey (edited September 20, 2000).]

 

How much scratch do you want and for what?


Oops. Just saw your price. My Airtex external pump is not "supposed" to be run at more thatn 16psi regulated operating pressure, that's why I want bigger injectors. Plus, I am a nut. I will sooner or later try for 400hp and don't think it's possible w/61's (or 65's?) unless at some insanely high FP's... Looking like 2" TBI is what I need. If that guy/gal falls through, post a topic w/my name on it so that I can reach you, k? I may be interested, not sure if any/worthwhile advantage to the 55's I have now.

[This message has been edited by FastBroker (edited September 20, 2000).]

[This message has been edited by FastBroker (edited September 20, 2000).]

 

ok re the post for parts availability,

IMO you'll need a bigger pump regardless unless that pump can maintain that 16psi at relatively high volume. As the duty cycle of those inj increases as you approach your goal hp, you will see a pressure drop and a consequent decrease in fuel pattern and atomization. I'm running the pump TurboCity specs for their higher power level TBI motors and it will push 25-30 psi at a relatively high volume (not sure about rating). That way you have some overhead in your pump capacity to accommodate potential pressure drop due to long pw.

 

In order to support 300hp @ .5 BSFC you'll need roughly 150lbs/hr of fuel. Two 83lbs/hr injectors running at 90% duty cycle will flow approx 150lbs/hr.

400hp at .5 BSFC and you'll need 200lbs/hr of fuel. Two 111lbs/hr running at 90% duty cycle flow aprox 200lbs/hr.

Or like has been said, smaller injectors at higher pressures. 65lbs/hr units rated @ 10psi need to run approx 16.5psi to flow 83lbs/hr and 30 psi to flow 111lbs/hr.

 

My Airtex pump will handle the volume but at presures lower than or equal to 16psi. Shoulda bought the higher-pressure version, I guess. When I bought it, 16psi semed like a lot more than was req'd. I also run an in-dash AutoMeter Fuel Pressure gage with the isolator. I love that gage, man. Piece of mind. Basically, don't want to go over 15psi. Maybe I'll have to run two small TBI assy's, huh??? That'd be alright w/me, too, but not sure of the manifold choices...

Turbo City says no GM injectors flow more than 75pph, by the way (I'm sure he means at OEM pressure). They say no such thing as 80 or 90's for OEM and if there was, it would be great...

[This message has been edited by FastBroker (edited September 20, 2000).]

 

hes wrong, there are 90 lb injectors and there are 80 lb injectors
they came in 454 trucks


FYI the only way you are gonna make the power you want is by raising fuel pressure

not only will that be the easiest way to give the amount of fuel you want, but more fuel pressure atomizes the fuel better and makes a steeper injector spay cone

 

Yeah, I don't trust TC, man... No way!

What if I use two small (1-5/8"?) TBI assemblies, Pablo??? w/55lb injectors? Lots of them around here off of trucks (no 2", though). Should be able to get some serious HP outta that w/some PROM work, no? Wonder if injector drivers can take 4 injectors...

 

I sense sarcasm

 

Nah, not me.

 

fastbroker, not to rub it in but i have the 454 and some 65 lb per hours, but they arent for sale, im using the tbi and want to eventually use the injectors, i am wondering what youve researched about power output from this combo and why you want it. i did it cuase i got a deal. Only now am i thinking about what i COULD do with it.

 

snfl,

I just got most info from this board and Pablo. 454 2" unit (with 80 - 90 lb injectors) will just simply flow more air and fuel. I have a modded 350 and need the flow. I'm just looking for the 65's to screw with my smaller (1-5/8") TBI unit that I am now using to get my feet wet w/PROM programming. I may actually go with a dual TBI setup, now. Looks kinda cool and not too costly... I can get another TBI unit off a 350 truck (like the one I have now) for $150 or less at several boneyards around here.

I just figured for now, someone could part/sell some 65's, if they didn't need them.

I'm prety sure 65's will be too small for a 454 TBI. If you are flowing enough air to use the 454 TBI, you will probably need the 80-90 injectors it came with... IT could be true that a smaller TBI is best for you, especially w/305. Pablo's vehicle is a good example... Maybe we could figure someting out between us to make us both happy? I just want everyone to be happy, man...

Whatcha running/building to need the 454 unit? me: 350, 240/190 heads, 214/224 or 224/234 cam, true dual w/Corvette OEM stainless shorties, 9.25:1CR, Strip Dominator intake (TALL single plane), custom PROM (soon?), blah, blah, blah

Please help/work with me...

 

hmmm, what am i building?? The 454 is a preparation for things to come, i thought it would be a good first step. I hate to say my "future mods" because everybody always says things that most people know they are never going to do but are just dreaming. But i will tell you my plans anyway. I plan on buying an intake very soon to match the tbi. I have a mechanic that works for me, this guy who has a nice selection of small block parts, hes owned almost 20 camaros in his life already and hes only 26. Years ranging from first to thirdgen. I am looking for headers, that i can get here cheap on thirdgen from the classifieds, like mostly everything else ive ever bought and will buy for my car. I have a gear drive, spoiler, subframe connectors, ignition system, and a few other small things that i have but havent put on yet. Ill buy nothing that wont eventually go on a 350, My family owns a complete auto repairshop. exhaust electronics, etc. we are in the works of buying a chevy dealership too. If that happens ill be buying lots of cheap parts, he he, and maybe selling some too. The car is a project, yet a daily driver. I just want to do everything at once. Ive been researching suspension setups, and will probaly go with drop spindles, and many of spohns pieces. combined with some koni reds. Heads will most likely be bought after i buy a 350 block. I havent done most of these things because im in college, and am waiting for some free time. Girlfriend and school take up most of my time now, the car will most likely come, thought most say it will go, when girlfriend becomes wife. And by then, few years, i should have a complete arsenal to build a high performance machine. That does sound a little dreamy doesnt it. how bout this, the tbi was cheap, i bought it and am building from there. I will help you find a 454 though. ill call round tomorow to all my parts stores and yards. Ill even go look at my local u pull it. The 65ers, ill check on too. Sorry so long, but you know how it is.

 

That'd be great if you can find 454 2" unit. I can't find any 'round here.

I should let you know that I'm also considering buying another 350cid 1-5/8" CK/Truck TBI throttle body (55lb injectors, like I have now) to make dual TBI system. Could be cool, eh?

Good luck with all of your work to come.

 

Could be very cool. I like the idea of the dual tbi setup, and it looks good too. Im looking today.

 

What about a ZZ4 intake with World SR torqer heads?

 

The factory TBI intake that came on my 350 from a 1992 chevy van is taller than a performer RPM. The air cleaner and spacer ring that fit with a Q-jet on a performer RPM spread bore intake crashed into the top of the engine compartment and dog house with the TBI and TBI intake on it. The TBI itself is thinner than the Q-jet too. I can see from one port into the other straight through the intake. It is by no means more restrictive than a carb intake. It is probably much better than many dual plane carbed intakes. I was making 267 RWHP with that intake and reworked swirl ports on a 350.

As a side note the TBI on it is also weird. Mine has a different front pull configuration. The throttle cable pulls from the fron and the TV cable attaches to the rear.

 

See if you can add to this. It's adapted from an earlier post of mine that I neglected. It might be useful to put into a Intake Manifold sticky or tech page someday.

Part numbers, runner volumes etc would be useful additions.

----------------------------------------------------------------

The following is incomplete, so if you have data to add, please do. And remember that the following only applies to production intake manifolds used on TBI v8 applications. AFAIK, all these intakes are aluminum, and should have a raised snowflake cast into the factory aluminum intake that denotes the Winters Foundry, the OEM that made the parts for GM.

There are at least four TBI intakes for GM 305/350 (LO3/LO5) applications:

1-3. Fcar, Bcar, and C/K lightweight truck/van which all use a Rochester 220 TBI unit (2 bore, single unit);

4. Fcar Crossfire intake used on '82-'83 305 (LU5) Fcars (as well as 82, 84 Ycars on the L83 350). Crossfire intakes were also TBI for those that don't know.

As below, dimension "A" is from the manifold-to-block flat, above the timing chain cover and the front fence above the lifter valley, to the mounting flat for the TBI. Dimension "B" is similar to "A" except that it is measured at the rear of the manifold (next to the firewall).

When A and B are the same, then the manifold is flat. I believe these are the same dimensions used by Edelbrock and Holley, and the main issue for each is hood clearance. A and B usually aren't the same because most sbc's are tipped so that the crankshaft axis is not parallel to the ground (the distance is greater from crank to ground at the front of the car), so B is usually larger so that the TBI (or carb for a carb application) is level when mounted on the engine.

==============================================

Fcar (L03), single 2-bore TBI
casting number: xxxxx482 (need to get the rest of the sequence xxxxx)
(also 10166133 ?)
dist hole ID = 1.375 inches
rear base -to- top of dist pad: ?
dimension "A": ?
dimension "B": ?

==============================================

Bcar (L03/L05), single 2-bore TBI
casting number: 10105143
dist hole ID = 1.75 inches
rear base -to- top of dist pad: ?
dimension "A": ?
dimension "B": ?

==============================================

C/K truck & van (L03/L05), single 2-bore TBI
casting number: 14102182
dist hole ID = 1.375 inches
rear base -to- top of dist pad: 1.10"
dimension "A": 3 and 3/8"
dimension "B": 5"

==============================================

Fcar 83-84 (and Ycar 82, 84) LU5 (and L83) Crossfire
casting number: 14031372 (1982 model, no windows between runners)
dual 1-bore TBI
dist hole ID = 1.375 inches
rear base -to- top of dist pad: 1.00"
Measurement "A": 3.75"
Measurement "B": 3.75"

==============================================


NOTES: PaulD told me that the C/K truck TBI manifold is visually identical to the Bcar manifold; according to other posts (not by PaulD) here on ThirdGen it is taller.

I'll assert for now that the Bcar and Fcar manifolds differ only in the size of the hole for the distributor... and of course, they differ in the casting number.

The runners in the TBI intake manifolds have very small cross sectional areas and are not radiused in any significant way as the exit the plenum under the TBI. The plenum is a dual-plane design with a small thumbnail-size window that connects upper to lower planes. The window is directly under the TBI. The plenum is surrounded by a coolant jacket that's not visible unless you cut into the intake.

My neighbor ported a factory TBI intake (91 Caprice LTZ) but he also modded the rocker arms and added full duals, so the noticeable performance gain was due to the sum of the mods and not just due to the intake manifold work. I'd say it helped but I cannot say by how much.

If you are thinking "Why bother with the stock manifold?", then you might be right if you own a truck or Fcar because you can bolt in just about any aftermarket carb or TBI intake. It gets harder if you own a Bcar though especially the 91-93 models.

OTOH the factory TBI intake manifold is aluminum and light so if the flow can be increased (and evened out between the upper and lower planes) then it might be useful to keep it. Fast355 obviously showed that the factory TBI intake allows enough airflow to measure 267 rwhp, and that means around 300 fwhp..... which probably is more a flow restriction from the stock small bore TBI than from the intake manifold.

 

My casting number on my 1992 G20 K-vin 350 intake is 10166133. It is not like any L03 intake I have seen. In fact I have only seen one other one and it was on a 350 in a box truck.

EDIT-Here are the dimensions.

Dist. Hole = 1.375"
Rear Base-to-Top Distributer Pad=1.10"
Dimension A= 5 1/8
Dimension B= 5 1/4