92blackbird

I've seen a lot of tbi spacers advertised in summit and jeg's both 1/2 inch and 1 inch. I have access to a machine shop and can make my own, but do these help the tbi or not? We used to use carb spacers years ago when I was racing and they did help, but I'm curious about this specific application.

TBI305Camaro

hows the 670cfm TBI working on your 305?

Joel Geerling

Sorry I don't have dyno numbers for you on the TBI spacer "mod."

All I can say is that you're not gonna notice any SOTP difference from it. Seemed to me like I had a better throttle response post-spacer install, but that could just have been me hoping it wasn't a complete waste...

dimented24x7

iTrader: (2)

Just outta curiosity, what is the peak flow rate that can be atchieved on a stock tbi unit w/ spacers?

JPrevost

It's in the 550cfm range with the 1 11/16" bore all worked over. The 2" bore versions don't have any ridges to remove and the 2" is nice for 670+cfm. Don't confuse these numbers with carb cfm ratings. They're measured at different atm so it's not comparable in that sence. Just understand that with a stock TBI you can make up to 300hp on a 350, any more and the TB will become your bottle neck. That's the general rule, anything more than 300hp get a 2" bore TB, either the holley or the 454 unit.

dimented24x7

iTrader: (2)

sweet.. the crate tbi engine im planning on gettign is 300 hp so thats one less thing that i hafta replace

ir0cz

Which engine are you getting?

ir0cz

That stock TBI handling up to 300HP, is that w/ stock fuel pressure also?

92blackbird

been gone for a while, new job etc., that's what I was hoping to hear, crisper response. The 670 works great. For now I just bored the stock manifold, left fuel pressure stock. It really seemed to improve the mid-range of the car. It will pull in excess of 5000rpm any time I want. It seemed to run out of air around 4500-4750 before. I'm still curious if the spacer allows hood clearance with my 9 x 3 k&n? On a digital stop watch the 0-60 is down to 7.9 / 8.2 sec. from the 9.5 sec.+ of when I bought the car.

Snowdog 91 Formula

How high of a spacer do you want?
If your car is the same style as mine, I did not put the spacer in with the stock hood. I am guessing you would have to cut the bolt and put a lower element....
Maybe you can get away with a 1/2" spacer and cut the bolt 1/2" lower and use a 2 1/2" element. (still not too bad).
Just my .02
-Snowdog

Audiman

Usually the aftermarkets run a screw design to tumble the fuel mixture. What actually works good on the intake is a tornado. I run one. www.tornadofuelsaver.com

JPrevost

No, the stock tb unit will not support 300hp with stock fuel pressure. The injectors and injector pod with fuel pressure regulator is a totally differen't story. Just like how TPI injectors are a totally different matter compared to the tube, plenum and base choice.
The injector spacer is a good mod for hp modifications and the spacer is really only a tuning aid. From what I've gathered and many shops have proven...sometimes it's for the worse and can hurt the output of the engine. The tb spacer basically gives the intake runners more volume of air and fuel to draw from. The problem with the spacer is that it adds volume but there are some reasons why not to use them, I just can't remember all of them right now and I don't feel like going over this again considering it's been asked about 50 times since school started.
It's adding volume and kind of a band aid fix to the fact that the manifold wasn't designed for anything more than a 350 making 210hp (truck TBI systems). If you've got a few mods then the spacer might help so long as you tune the rest of the car.
I would never buy one of the units, it can be made from a block of aluminum in a relatively short period of time. Whatever you do, don't get the spiral piece of crap. Would you want to slow down your exhaust? no, so why do it to the intake, it's basically the same idea. If you've done bolt ons but never adjusted fuel pressure and checked for a 128 BLM then you're probably running slightly lean. When you add the restrictions to the intake (stock air cleaner, that spril port throttle body spacer), you're slowing down the air and so you've just made a richer air fuel ratio which can actually make your car feel faster.

Audiman

I run the tornado and you can feel the difference. I dont know how it will do in a camaro, but in a 93' Burban it rocks. The web site has dyno charts.

ir0cz

Wow, somebody that actually bought one of those things....haha. No offense meant, and i'm not saying it doesn't work, i just haven't met too many people that bought one....you're the second.

Audiman

I couldnt rely on that weasel on the infomercial so I just checked it out myself.

ir0cz

Yea, the old "Cowabunga" guy w/ the vette didn't help convince me either.

Audiman

Dude looked like Al Unser in the prolong commercial!

JPrevost

It's pure unadulterated bull****. I wouldn't install one of those tornado pieces of crap. You want better gas mileage, get a tune up and evoke highway mode with an eprom. There is NO mechanical way to save on gas mileage when your ECM adjusts the fuel flow by reading the o2 sensor information. The tornado effect slows down the air velocity. Ever heard of swirl port heads? You had better...because every Lo3 and Lo5 has em and they're crap. The "swirl" and slow down the air. The swirl port heads are great for the street if you want less power under your hood. The only real way to get better gas mileage and keep the power is to have a more efficient engine with a custom eprom controlling timing and accurate fuel pressure with tuned VE tables. The swirl with that product slows down the air. Want to prove it to yourself? Flush a toilet, how long does it take for a piece of paper to get flushed down. Now take a bucket of water, dump the bucket down the toilet and see how long it takes. Wow, wasn't that easy. Same thing only it's with air and fuel. Another thing you might want ponder over is how an engine makes power. It burns fuel and air. Not enough fuel and too much air = lean and not a big "flame" and less power. Too much fuel and too little air = rich and not a big "flame" and less power. Gasoline engines aren't the most efficient engines in the world, they've been around a long time and just look at all the heat loss in energy with the cooling systems! Don't get me wrong, I'd love to have good gas mileage AND eat my cake too but with a small block and deep gears it's not going to be the best. I'd like to see some more independent studies done with these so called helix bore spacers and tornado products. Heck, there was (is) an electric fan super charger device a while back and even that proved to be a joke. I like how people think there is an easy solution to everything when there never is. You want more power, you need more fuel. Want better gas mileage, evoke highway mode in the ecm, tune everything and make your engine more efficient, don't starve it from air!
Grumpy made it very clear to the board a while back when he posted information regarding those companies "dyno tests." What they did was take a bunch of cars and find which ones were running lean. They dynoed them with the lean condition and then installed their tornado. What happened was all of a sudden the engines were getting less air but the same amount of fuel. What this does is lower the air to fuel ratio and in most if not all cases this will product more power because of the better air fuel ratios, not because of the swirling action crap. If somebody wants me to prove this I will. Send me the unit, I'll dyno it on a stock Lo3 that is running lean, install it, run it, tune the Lo3 without the tornado, run it tuned with the tornado piece. I'll bet right now that I'll get more power without the tornado.
Want ANOTHER example as to why this swirling is a bunch of bull...crossfire injection. When did it come out, early in the vettes and thirdgens. It was to get better gas mileage. Did you know that under each TB in the intake manifold were some "spinners" that swirled the air. Kept the fuel in suspension because it did a good job or moving the air WITH fuel (unlike the tornado) across the ruff surface of the intake runners. This kept the fuel in suspension longer and worked well for gas mileage. The problem with swirling above the throttle body or right before the valve is that it has no purpose other than to become a restriction. At least the crossfire intake was thought out unlike the tornado piece of plastic. Question for you guys, don't you think GM would have kept with a technology they knew "worked." Kind of like EGR! Nah, instead they junked the whole swirl stuff and just used a better design combustion chamber that created high swirl and turbulence for the burn. The combination of the better chamber design, intake runner angle/shape, and other small changes were the future, behold the LS1 and the new 270hp inline 6. What amazes me more that the pushrod LS1 making over 350hp and getting near 30mpg on highway is how people actual buy those helix bore TB spacers and the tornado before they bother to tune their vehicles with some adjustments with fuel pressure. THAT, that really surprises me. I'm just glad I'm not such a sap and that I had such great mentors to show me the light (Grumpy, Glenn, FB, many others).
Wow, turned out to be a long reply but I hope you guys do your own research and don't just listen to me or those tornado crooks. Back to study, damn all niters just for calc, hey, anybody want to take a calc exam .

Audiman

My swirl port heads are already gone and I am waiting on my Vortecs. Tumbling, atomizing and swirling air does make a difference because of fuel atomization. Hence fuel atomization of injection versus squirt guns in a rotten-chester.Why do you think helix spacers are spaced, to make velocity compensations for the restriction of the air changing it path of flow. If it slows down air but makes power I am still all for it, obviouslty it is still getting the job done and utilizing the intake system that the manufacturer did it's supposed R&R on. A tornado may not flow an Airaid but it does a decent Job on a 1993 Suburban with a torque tube even if the infomercial guy does look like a character from Dick Tracy! Last of all if the incoming charge is atomized it will combine with the air charge. It wont fly down the intake like a piece of toilet paper. Dont you remeber fifth grade with the two liter bottles joined together and the colored water? Tornado baby, Tornado!:rockon:

Snowdog 91 Formula

Okay Jon is more correct in this one folks!
The design of the intake manifold will make more of a difference in this matter. What the "Tornado" does is pre-atomize the air/fuel mixture. Now, if you think about it, atomization is actually happening as the fuel/air is going into the chamber and the manifold is more doing the job than the "Tornado"
You slow down the mix... make it run richer.
Granted, you might get something better out of a stock manifold, but not with a better manifold.
The worse case scenario is bog.
Yes you will get a little more volume to your intake.... It's something you can do with a standard spacer, but the magic is what happens inside the chamber, not what the Tornado does.
You can put a regular spacer and get a better result.
Why? Because the fuel isn't suspended BEFORE it reaches the chamber!
What I am trying to tell you is you will get results from any type of spacer you put in there. Better or worse depends on your manifold more than the "Tornado"
My .02
Oh! Put a standard spacer in place of the "Tornado" the same size. You will most likely get the same result and use LESS gas!

davidjon_99

I recently cleaned up and rebuilt my TBI unit and at the same time I removed my helix core spacer because I thought it wasn't doing anything. I ran it that way for a couple of weeks and did numerous DataMaster scans going to/from work. I found that at WOT I was getting a lot more pinging and acceleration was suffering as a result. I put the spacer back in this weekend and my initial results show much less pinging. I still have a lot more data logging to do to make sure.

This is just an initial observation on my part and I'm interested in the more knowledgable folks' speculation on why this would happen. I basically assume that it is because my intake charge, especially at WOT, is atomized more as it enters the chamber.

BTW, my truck still has the swirl port heads, but not for long, I hope.

EDIT: Okay, I read through the other threads and have some ideas of why my knock count is lower with the spacer. Tell me what you think.

1) The spacer could actually work and help atomize the air/fuel charge more efficiently. This would be good.

OR

2) The spacer could be making the air/fuel charge more rich by reducing the air flow into the cylinder, as mentioned in one of the above threads. This would be bad because it's reducing the overall amount of air flow.

The performance improvement I feel with the spacer could be the result of less spark advance that the ECM is taking out because of less knock. In other words, without the spacer (possibly a more lean mixture) my knock count causes the ecm to reduce spark advance by as much as 3-4 degrees. With the spacer (possibly a richer mixture, with less air flow) I still get knock, but a lot less and the ecm only reduces spark by 1-2 degrees and recovers more quickly.

I guess the key is to find out if I'm running lean at WOT without the spacer.