Need pics of draw-thru

[mygrain]

Could someone post pics of a draw through system from a carbed TR? Im drawing up some plans for a draw through system and a Chevy V8.

 

[80TTAPaceCar]

Hope this helps

 

[gunnervirus]

Here's another:

http://briefcase.yahoo.com/bc/gunne...s/lst?&.dir=/the+gunnermobile&.src=bc&.view=l

Ben

 

[b4black]

This website has a great picture and description.
http://publish.uwo.ca/~agrehorn/turbowriteup.html


Why are you choosing a draw-thru vs a blow-thru? (just wondering)

 

[mygrain]

I just think it looks cool and Im hoping it will work well. Ive noticed that the distance from the compressor to the intake manifold is not very long. Does it matter how long the air must travel from the compessor to the intake? Will it cause fuel distribution problems in the intake manifold? I wanted to avoid a carb box because its such a pain in the butt to take apart to jet the carb when it needs adjustment. I also wanted to keep the turbo far from the intake because I wanted to construct a water jacket around the intake tubing to cool the air charge. That should cool it down substancially since where I want to place the turbos is about two feet from the intake manifold. That ought to give it ample time to cool while going through this water jacket. Opinions on this, anyone?

 

[b4black]

If I remember right, Buick said the path between the carb and intake need to be as short as possible and downhill to decrease the turbo lag. Even as they did it, there was plenty of lag. I think if you add a water jacket, you'll make this worse. And it's possible that the fuel will condense out in the inrtake.


Carb boxes on a blow-thru are old school. I have heard there are some Holley carbs that can handle 20+ psi with just minor modifications. Plus you can add an intercooler. Adding a blow-thru turboto a NA engine is easier than adding a draw-thru.

 

[mygrain]

Do you have a part number for this carb? I may have to look into it. Im only planning on using about 9/10 psi on premium pump gas with an 8:1 CR. This is a 283 punched out to a 302 (4.0 inch bore). I am using some shorty tube headers turned so the exhaust goes toward the front of the car where it will go into the exhaust wheel. Thanks for your help you guys.

 

[Turbo-Rich]

I, myself, think that mygrain is on the right track. A draw thru I believe is superior to a blow thru system. Blow thru's have limitations of around 30 psi & DT has no such limit. Tractor pull engines used to see 100 psi of boost back in the 80's
That being said, there is two negatives to a DT system.
1. HEAT
2. LAG
BOTH can be easily & cheaply overcome. Especially compared to the high cost of intercoolers. IMO (lol) intercoolers are restrictive, expensive & unnecessary.
The turbo industries want your $$$$ They are an industry that promotes a heat pump to boost your engine, then advises you to buy an expensive intercooler to get rid of some of that heat. This is a inefficient method of removing heat and it restricts flow, reducing power & performance at LOWER rpm levels where it's needed. The whole principal is fundamentally backwards!
Also, most IC's are totally ineffective below 4,000 rpm where most of us spend our time driving & they are considered totally unessasary when boost is below 10-12 psi. like you plan to run on that Cheb.
I think your idea of building a water jacket around the intake tubing to cool the air charge is quite clever actually. I'll bet you'll be able to run a lot more boost than 10 psi also, it might suprise you. There are other creative ways I've seen ppl use to bring the heat of the charge down such as cold water systems that wrap the compressor housing & feed cold water into the intakes heat risers & air intake tract. I've also seen cold air "blown thru" the carb. This not only cools the turbo's charge of air, it also can be used to reduce turbo lag to almost -0-. Pretty neat!
By changing the way your sytem compresses air, you can produce a cool charge in the first place while actually INCREASING flow as opposed to decreasing it with an IC.
As for your turbo being so far away from the intake, I wouldn't really worry about that either, as long as you go horizontal & down with the intake, you should be fine. Did you know that the elbow at our cars turbos outlet reduces flow by 10% alone? Buick did say the path between the carb and intake need to be as short as possible but that doesnt necessarily hold true today. Have you considered building equal length tube style of intake? Not only would it look wild, it could be very effective.
I have many, many ideas I plan on implamenting on my T in the future. Gotta get everything up to snuff first tho. Your project sounds pretty fun. I thought of throwing one of my spare t3's on a V8 for kicks myself, but I've kinda been eyeballing this Ford
200 ci inline six I have sitting in my '64 Fairlane. It has more bolts per cycl. than most V8's & more crank overlap. Plus the blocks are thick, the cranks are strong & parts are laying all around for just about free. I think I could do the whole project for next to nothing too. Anyway, that's down the road.
FYI, the carb. to go with if your gonna blow thru is the Holley 4776.
They're only around $240 & are already sealed. a man named **** Datsun is actively trying to find the limitations of carb'd BT systems & has reached 30 psi recently on a 30 inch Stude motor with no ill effects & says he plans on going higher. This is the model of carb he is useing & suggests. Pro charger claims that carbs actually cool the carge up to 30% compared to F.I. Just one more reason, besides cost & complication, that I believe carb's are superior to F.I.
As far as draw thru goes I believe a Weber side draft carb. would be optimal. They are infinately adjustable (but costly) & you could mount it directly to the turbo's inlet greatly reducing lag. They would also save a lot of space too.
Ultamately, I believe the best carb'd turbo Buick reciepe would be a twin turbo DT system with two Webers & air amplifiers in front of 'em. Lag would no longer be an issue then all you'd have to work on is removing the heat. It would be a linkage nightmare tho
Ryan McMakin at Lone Star racing is supposedly working on a twin-sequential turbo's Buick V6. I guess that would be the "ULTAMATE" carb'd Buick V6

 

[b4black]

Ah, D!ck Dotson. I'm surprised with name hasn't come up here before.

I have his Turbocharger "book". He has some really good ideas, but I'm not sold 100% on some of the things he suggests. I don't believe the industry has a conspiracy going on to keep power down and make money selling intercoolers. I think if there was a turbo system that could outperform everything else, somebody would market it and make big bucks. Maybe D!ck is on the right track, but I will wait to see others try (prove) it. I think the stock Buick carb/turbo has a lot of room for performance before hitting the wall (where performance starts costing really big bucks). Fred Carrado has taken his engine far with the stock style set-up.

I think his book is well worth reading, but everytime he brings up how bad EFI is, I just think about all the 86/87 Turbo Buick running 12's with just some tuning and a few bolt-ons. He seems to ignore these cars. The carbs have pros/cons, and EFI has pros/cons. I don't think one is clearly better than another, just different.

This thread's getting really interesting!

And on the same note, I don't think blow-thru or draw-thru has a clear winner, just different. It's choosing the right tool for the job.

As you just mentioned:
Draw-thru has no boost limitations, but heat and lag.
But, blow-thru has ease of adaptation to NA engine, possible IC, but boost limitation.
(agree/disagree?)

I have a '82 GN that I plan on building up this summer. It's motor has been butchered by a previous owner, so it's like starting from scratch. I thought about both a BTand DT system, but haven't made up my mind yet. Here's my current thinking (subject to change of couse).

Since the 10 sec 86/87 TR's are only running about 20-25 psi boost, I don't think the boost limitation factor comes into play. I won't be running 30+ psi either way. (This should carry over to a small V8 as well.) I have pleny of DT parts, so actaully the BT is the harder system to install for me. (I would need to collect plenty of parts.) That leaves me with the heat/lag issue. I think the BT has the edge here with the IC. Plus many 86/87 performance parts could be used with the BT, like a Terry Houston downpipe.

So at the moment I think I will start with DT, but maybe later swith to BT. BT could always become a liability at very high boost, but I'll cross that brigde when I get to it, IF I get to it.

If I didn't already have the DT parts and were looking to add a turbo to a NA engine, it would BT for me hands down, just because it is easier and more practical for lower boost (<20). If I were going to the tractor pulls and needed 50 psi, then that would be a different story.

 

[Turbo-Rich]

Funny , I can't say **** (Dìck). lol.
I also suprised his books/newsletters/newsgroups hasn't come up here before.
I've been dying to discuss some of his idea's with someone but here I thought really wasn't the place because I believe the sfi guys would take great offence to what he has to say & I wasn't wanting to start a F L A M E thread. But for us carb. guys, I thought it was full of brilliant idea's. Not only the idea's he drew out but his theories & & all the fresh ideas they spawned in my head. Not to mention all the links that were provided. I still haven't been to all of them, theres just soo much info. to digest. I'm not totally sold on his whole "system" idea yet either. Time will tell. I am just aprehensive about adding another belt driven anything. I'm getting regular updates from him & things are coming along with the TERMINATOR project. Also, he says he HAS cracked 30 psi with a carb. now & still going to go higher until he finds the limit I've been talking to a few ppl in his newsgroups that are experimenting with some of his ideas with good results. I'm not at all suprised, he breaks things down to plain common sense, no bull. His bools are really more of a compilation of newsletters strung together than a book. I believe he even contradicts himself here & there. Another thing is that he touts the DT system as being clearly suoerior but you notice he personally is running a blow thru. I imagine he'll be switching to DT when the Ternimator thing gets going. I am in agreement with him that "the industry" is out for your cash but I wouldn't call it a " conspiracy " LOL. They are a buisiness & they surely don't wanna push free mods that you can do yourself. Why do you think they pay thousands to have an add smack dab in the middle of your magazine article splitting the damn thing up?
Every car I've built I've been told "you can't do that" or "that wont work" by the aftermarket companies techies. They just wont promote "junk technology". My openion has alyays been, especially with carb'd TB's, that there isn't going to be a "magic bullet" that's gonna make our cars fast. However, a whole lot of innovative, even teadious & seemingly not worth the trouble can all add up to a lot. I thought Dìck's book brought a fresh look & A LOT of hope to the carb'd TB. Some of the stuff info. didn't necessarily hold up to IC sfi'd TB's but looking at it from the cost effective standpoint, I know where he's coming from. I would cost cosiderably more to push 30 psi thru FI than it would carb's(s).

I don't see a clear winner between DT & BT either. I think, starting from an N/a motor, it would be eisier to go DT simply because of of the carb/fuel mods. I also don't see the point in wanting to switch to BT without even maxing out the DT system first.(which your planning to do anyway) That's like what, 18 psi I believe? That's quite a bit of boost! Definately enough to make a fast enough ride with.
I do like your idea of using the '86-'87's pipes & everything. That would look beautiful under the hood & you have more aftermarket parts at your disposal. Have you considered using your '83 headers? You could mount whatever turbo ya wanted to on the pass side of motor & have an up pipe made to go to it from your existing headers. Then you would just have to build thei intake piping to the IC & intke. It woudn't be as pretty but it would cost hundreds less sinse you pretty much have everything you need already.
I think the more experimenting we can do & in as many directions as possible can be a very healthy thing for our hobby. Like this discussion. I would much rather take opposing sides than agree with the main stream of thought. Thats where all the really good idea's come from


What did you think aboput what he had to say about C02 injection? He was against it becuz it being so cold against the turbine but I've prob. 5-6 cars (websites) claiming it woked wonders for there cars.

 

[mygrain]

Tell me more about this CO2 injection. Another thought that I was throwing around was to use a TPI manifold with the injector bungs welded up and get it all hogged out and use The blade on the front of it as the throttle control. Ive heard that the closer the valve is to the cylinders, the less lag you have. True or no? I could just run the carbs WOT all the time and control the throttle with the blade on the manifold. I have got to get a CAD program so I can start drawing this stuff up. I am taking all opinions into consideration here, even those of the skeptics

 

[b4black]

The CO2 doesn't sit well with me. Too much like N20. Comes out of a bottle that would need regular filling. I want somethings that's always there and used every time. (But water injection doesn't bother me for some reason. )

The idea I really liked (but have doubts) is the smog pump spooling up the turbine. The factory smog pump line and the up-pipe run right next to each other. Weld a nipple on the up-pipe and connect it to the smog pump with a peice of high-temp rubber hose.

83/85 headers may work for a BT. Actually, the DS header and crossover are the same as the 86/87. Buy changing to the 86/87 passenger side header, all the 86/87 factory stuff would work as is.


mygrain, on the TPI with the throttle body, I think the idea is to get the fuel souce (carb) as close to the cylinders as possible. The less distance the fuel travels, the less lag. I think that there would be metering problems by having the throttleing (at the TB) with a turbo between them and the venturis (in the carb).


I like experimenting, but I also believe in the KISS theory (Keep It Simple, Stupid )

 

[Turbo-Rich]

Originally posted by b4black
The CO2 doesn't sit well with me. Too much like N20. Comes out of a bottle that would need regular filling. I want somethings that's always there and used every time. (But water injection doesn't bother me for some reason. )

Well, I hate N20 myself also. The C02 does't run thu your motor though, just the exh. housing. If it's gonna blow anything up it'll be the turbo at least & not the motor. I've thought of trying this out since I have a few spare turbo's now but I thought if I did I would introduce it sooner in the exhaust system than the housing so it would have time to merge with the exhaust gasses & warm the charge up some. Still it's a pretty hypothetical idea right now & I could only see it being advantagious in a drag race. Also one would have to work out a way to turn it off & on. COLOR=blue]They make lightweight)?) fiberglas bottles for food service.[/COLOR]



The idea I really liked (but have doubts) is the smog pump spooling up the turbine. The factory smog pump line and the up-pipe run right next to each other. Weld a nipple on the up-pipe and connect it to the smog pump with a peice of high-temp rubber hose.

I like that idea also. I figured you wouldn't since you like to keep the smog stuff hooked up I thought. The pump should add volume across the whole rpm range & hopefully off-idle where more volume=more spool. I thought an easy way to test this out would be to remove the O2 sensor & run a hose from the smog pump to the O2 hole. I know this wouldn't be right to drive around with it that way but iy might give you an idea of what kind of volume you could get out of it.
[Since my system is apart right now & I'm not planning on hooking up the smog stuff due to the fact it's all in such sad shape. I should have a nipple welded in the up pipe like you were saying & give it a shot. I didn't know what the heck I was gonna do with that huge a/c, smog pump, alt. bracket anyway. I happen to have a new smog pump we tried out on Tonyas T-type also I could probabley talk her out of it.

What did you think about the Air Amplifiers idea? That idea seemed to make sense to me. The main draw back would be having to have a storage tank & a strong 12V compressor. I've looked around some & they aren't as uncommon as I thought. I even seen an overpriced fancier Jap. version that electronically metered the amout of air going into your intake tract that's supposed to keep the ideal amount of positive pressure blowing thru the carb/injector. It was like $2,000 though






I like experimenting, but I also believe in the KISS theory (Keep It Simple, Stupid )

Hey, did you just call me stupid
Just kidding

 

[Turbo-Rich]

Originally posted by mygrain
Tell me more about this CO2 injection. Another thought that I was throwing around was to use a TPI manifold with the injector bungs welded up and get it all hogged out and use The blade on the front of it as the throttle control. Ive heard that the closer the valve is to the cylinders, the less lag you have. True or no? I could just run the carbs WOT all the time and control the throttle with the blade on the manifold. I have got to get a CAD program so I can start drawing this stuff up. I am taking all opinions into consideration here, even those of the skeptics

From what I understand, the C02 is injected through a hole in the turbine housing directly against the impeller blades to supposedly force the turbine to accelerate faster & possibley have a turbo housing cooling effect. This system could probabley be most taken advantage of with a manual gearbox I'd imagine. Finding a way to drill thru the exhaust housing & the correct placement to inject it against the blades would be the real trick here. Dïck warned against this in his book due the C02 being so cold up against the HOT exhaust turbine. It was also mentioned that C02 could be used to "drop the temperature in a cool can to freezing temperatures at a moments notice".

Your TPI manifold idea got me thinking....(ouch )
You could use that manifold & mount the turbo where it's outlet is discharging directly in front of the air intake in the front of the motor. Then the carb. would be flowing directly into the turbo & into the intake. Very direct. Space might be a problem tho. Again, a Weber carb. would dramatically clean things up here & be especially good at preventing lag. Or it might be easier to go with a variable venyuri design carb. like the Predator for ease of tuning & to keep things from leaning out.
Some of the NMCA streetcar shootout guys have thier turbo's inlet at the very front of the car sticking out thru the body. Pretty wild looking, I wonder how much bug guts thier motors eat?

 

[mygrain]

hmm... A single turbo mounted right in front of the manifold, with a draw thru side draft webe carb and CO2 injection to use as a psuedo intercooler could just maybe work. I know Ive got that manifold laying around here somewhere, and those vortec truck heads. Toss in an old Lunati roller cam and some shorty tube headers and custom bend a few pieces up front and I think Ive got a real set up going on here.

Where can I get a side draft weber?

What size carb do you guys recomend?

CO2 is just regular compressed air, right? So can I just use my 30 gallon air compressor tank and put a braided high pressure line up to the console area, run a shut off on the console, run a line up to the exhaust housing, tap a fitting and just flip the switch when I need to.

I need to get back to drawing, this is getting good.

 

[Turbo-Rich]

I should warn you that the Weber route is a little pricey. A Weber DCOE is between $325 & $400. I believe they are avaliable thru P.A.W. but if not a good V.W. supplier should have them. They are supposed to be able to handle fuel requirements for everything from a 152 cid to a 1215 cid.
I wish I had a scanner so I could send ya these diagrams.
The main reason D.D. promotes the Weber carb. is intended to be used in conjunction with an an air amplifier or simply a compressed air line shooting into the fresh air intake tract 18" before the carb to merge with the incomming fresh air. It is theorized this "system" would bring boost lag to zero & should only require token amounts(w/a weber) of air to make a temporary "boost" before the carb. It's not really creating boost so much as it is filling the vaccum in the intake. You could have the comepressed air connected to a button or to your throttle to automatically come on when you punch it. Regular compressed air should work for this. You can't shoot C02 thru your motor, only (maybe) your exhauast hoising. The compressed air can possibley be used for cooling also. You could have your 30 gal. tank filled hooked up to a strong 12V air comp. in the trunk. Then when you route the pipeing up to the front of the car you could have it go thru a "cool can" or "heat exchanger" to make the incomming air ICE cold. This is another place the C02 could come into play, to help cool the incomming air. Yes, you do need a special bottle for C02 because of the high pressure but the are all around. I saw a 10 lb. one sell on e-bay for $20, You might even find one out back of a restaurant .
Hell, why not put some dry ice under your storage tank & build a C02 or ICE heat exchanger right before the air outlet at the front of the car. That should give you a freezing blast of air thru your turbo & motors/turbo's just love cold air. I think I'm going to give something like this a try but thru my q-jet. Only diff. is it will take quite a bit more volume of air to fill the vac. in the 90° intake.
With the Weber, the amount of air needed should be very small.
Do you have any thoughts on this Rich
Or possibley you can explain it better as I am no writer
I don't think spell ckeck would even help me

 

[Turbo-Rich]

Originally posted by mygrain
hmm... A single turbo mounted right in front of the manifold, with a draw thru side draft webe carb and CO2 injection to use as a psuedo intercooler could just maybe work. I know Ive got that manifold laying around here somewhere, and those vortec truck heads. Toss in an old Lunati roller cam and some shorty tube headers and custom bend a few pieces up front and I think Ive got a real set up going on here.

Sounds like you have a workable project on your hands.
Not only would it be origional, you might even break some of "The Rules" along the way.
Hey, just think where the air cleaner would be if you used a regular downdraft carb & set it up like this. I can just see the carb./air cleaner poking thru the hook just beind the radiator/grill area/lol That'd blow ppl's mind

If you can mount the turbo solidly onto the motor you might be able to get away with using flexable exhaust tubing wrapped in heat wrap as an up pipe from your headers. That way you could experiment with lenth & routing before you paid the $$ to have a set made.

 

[mygrain]

I wanted to use a K&N cone filter with some sort of cold air induction. I already knew that the CO2 injection would only go through the exhaust housing. This is gonna be fun. If only I had something to put it in...................

 

[Turbo-Rich]

Originally posted by mygrain
I wanted to use a K&N cone filter with some sort of cold air induction.

I believe they make air amplifiers that use K & N's on the end of 'em. The one's I found for sale were $110. Kinda pricey IMO, or maybe I'm just a real cheap áss
I was thinking of using my '83's stock fresh air intake & inroducing air in an out of sight spot on the underneath side.
Still not as good as an air amplifier. They are supposed to be capable of amplifying the incomming air charge by 29%.

You can use a fire extunguiser to store the C02.
That would be nice & stealth too
No one would suspect it being a pre-spooler & it should be easy enough to get refilled.

Using both cold air induction/amplification & C02 should really be something! You could also (in theory) add 1 or MORE large smog pumps to your exhaust system to add more volume.
How do you think you'll introduce the C02? Into the housing?

 

[mygrain]

I was just gonna drill and tap a nozzle into the exhaust wheel for the CO2 injection. Im not too worried about being stealth as of right now, if theres a turbo on there, noones gonna believe its stock anyway.