Inliners International Forums General Discussion Blown and Injected Using the early Buick GN or Pontiac drawthrough tu

I've used the early Buick turbo on a 225 MOPAR using propane, a 250 Chev using an SU carb, and this one I was putting together for my '37.
These units have a 3 bolt mounting flange. I take out the outside manifold stud, and use the inside one. Squaring the unit using the remaining stud, you find the back two holes will line up on the "bumps" on the manifold. I drill and tap the manifold for those holes and install studs. This and a gasket and you are ready to go. The manifold throat is a little smaller than the gasket, but there is little to be gained by opening it up.
http://usera.ImageCave.com/Greybeard/Mikes_pictures_001.jpg
When you first get the turbo mocked up on the manifold. you will find the turbine intake is pointed at the valve cover. It will need to be reclocked. The turbine housing is attached to the bearing unit by about six bolts. I spray mine for a couple days with penitrating oil before trying to loosen the bolts. On the the bearing unit you will see a flat spot near one of the bolt heads. loosen all the bolts a bit and then back that one bolt into the flat. This will break the turbine loose and you can spin it so that it points down and slighly out from the manifold. This allows for you to use a simple J or U bend from the exhasut manifold to turbine inlet.

http://usera.ImageCave.com/Greybeard/Mikes_pictures_003.jpg

You can use the factory intake with original q-jet if you want, or use and adapter for your favorite carb.

http://usera.ImageCave.com/Greybeard/Mikes_pictures_004.jpg

http://usera.ImageCave.com/Greybeard/Mikes_pictures_005.jpg

With this one I built an adapter to use a Carter YH carb. The adapters is built like a spool with enough room to get the mounting bolts in to the compressor housing, and tapped for the carb bolts.
http://usera.ImageCave.com/Greybeard/Mikes_pictures_006.jpg

I tried a couple airfilters, the little chrome bonnet and a corvair unit.
http://usera.imagecave.com/Greybeard/Mikes_pictures_007.jpg

http://usera.ImageCave.com/Greybeard/Mikes_pictures_009.jpg

This should be enough to start the conversation as I don't have many pictures left. A problem when a harddrive fails and you are using digital photos.

http://usera.ImageCave.com/Greybeard/Mikes_pictures_011.jpg

Sorry guys. I thought I understood how to bring in the images, but it didn't work. Sorry about the quality

Mike

Very nice,
good to see actual pics of what I have been saying for guys to use for a low buck turbo install. Thumbs up.

Would you care to comment on the performance,mileage, etc?

When do you get full boost?

Auto or manual trans?

How much boost can you get?

Ever run methanol injection w/thoes draw through set-ups?

Is it worth while to use a draw through such as your set-up?

Have you tried the Turbo Trans Am 301 CI turbo set on a L6?
Any pics of these set-ups in your cars?

http://picasaweb.google.com/sixpics/292#5270033625773996354

Thanks


MBHD

Here are some more pictures to go with Hank's post. They are of my ever/never ongoing 292-turbo-Megasquirt project. Very much as Greybeard described as far as '81 Firebird 301" turbo on an L6 GM intake. Mine was not as clean as Greybeard's as I got into the exhaust heat part of the manifold when I tried to match the turbo port to the L6 carb base. I have since switched to an Offey 4bbl manifold with the base opened up and an shop built adapter for the turbo. The TBI is '89 GM. I am thrashing through some Megasquirt/laptop problems that have drawn out for a couple of years. Had I been "Windows" competent at the beginning this truck would be on the road.

I expect lots of questions as it's hard to address everything in the first post.

Performance/mileage: The Mopar had a manual "overdrive" 4gear. It was first converted to propane, and then turbo'd. I used an old Clayton chassis dyno and did gas baseline(106RWHP), then set up the propane (96RWHP), and then did the turbo(158RWHP)@7.5lbs manifold pressure. It never suffered any detonation issues and I kept it @ stock timing. We were at the limits of our mixer. On the same dyno, a good running 350Chev would produce 155-160RWHP. Mileage with that car was allround 19-20 with occasional +/- 1or 2. Boost would come on about as fast as the throttle compressed the carpet and max by 2200. I was quite pleased with it overall. The car had about 15k miles when I put the turbo on it, near 250K when I sold it, and I was approached at a car show by the present owner who claims it's over 500K now. That what good clean fuel will do.

My first Chev was a 250 I put together with forged pistons, 1.94/1.6valves, and a cam I had Delta grind up. It was symetrical 204@.050/.502. I used an SU off a L4 Land Cruiser that had the same throttle bore as the size of the compressor inlet. After turning at least a dozen needles, and mucking with jet sizes for days we achieved 11.6AFR @wot, and a cruise of 14AFR. The engine was installed in a 64Nova. Using a Vega torque converter, it would instantly light'm. Took it to Bremerton raceway running with 7.5 boost and it ran 14.00s at 103. It would not hookup so the time was slow compared to MPH. Later we built a boost control bypass by bleeding off some of the pressure to the boost diaphram. We ran into detonation so I rigged a windsheild washer w/pump activated by a hobbs switch set to 5lbs. I adjusted the flow rate through a little brass needle valve I got at a the fish store to adjust air in a fish tank. I found that too much water put the fire out. We never took it back to the strip, but we did hit as much as 16 lbs manifold pressure with the boost control inop, and it hit that by about 2600. I didn't try alky, just water. It was scarry fast from the passenger seat as the car had lousy shocks and no suspension upgrades. At least I was terrified.
Mileage could have been good, but it spent a lot of time in boost. Also, I used a distributor vacumm advance unit from Dale Manufacturing that was made as an upgrade for a turbo Corvair. It had about 10 degrees of pressure retard as well as 12degrees of advance.
I've never used a blow through so I can't compare, but they do work pretty good as draw throughs, and it's simple to do. I haven't used the pontiac unit, and do to a computor failure, many pictures I can't retrieve.

I had a friend look @ those pics & is a Corvair expert.

He had said :
" The stock Carter YH side draft carb is O.K., but limits boost on a stock Corvair. It has to be a real limiting factor on the larger engine and better turbo. The Q-Jet would be the carb I would run. If he is running the YH, I would suggest the carbs with a body casting number of 17_ _."

He also commented by saying,,, LOL:
"Now I see where the old Corvair turbo stuff is going. :-) "


Just some FYI.

Yes, I can see that you could easily inject too much water & snuff out the spark, methanol injection is the better way to go now a days.
Example: http://alkycontrol.com/

I know all about the early Nova's bad suspension.
My good friends 66 Nova ,built 406 SBC,drum brakes & a street car, racing on the streets & many times @ a race track ,one I would race & compare/race my L6 Camaro to.
He never beat me BTW LOL
Thanks for the info!

MBHD

Hank
This may set your friend off. The carb is a '66 unit with the 1 7/8 throttle bore. What may set your Corvair friend off even more is the link in my sig. Go to view albums. My intent with this was not to make as much power as possible, but to work with the engine I had with cast pistons and stock cam. The '37 is very light and performance with the stock 250 engine was good. This was mainly for show and tell.

My friend is not mad ,he is being funny.

He was just saying the Carb is restrictive & just wanted me to know that.

You never stated you wanted to limit your power output so I just wanted to pass that info on in case someone wanted to run that sidedraft carb & thought it would make a lot of power,which it cannot, that's all.

Greybeard, did you ever try the Quadrajet carb? Just curious,feedback?

MBHD

I never tried the q-jet. Back in the '60's I picked up a '62 Olds F85 Jetfire. It had a single barrel Rochester If I remember right. I discovered that the shaft between the boost control diaphram and valve was covered by a piece of tubing, so I drilled the tubing and shaft and put a cotter pin through it to hold the valve closed. The thing was a Rocket. Blew off a 327 Chevelle and a single carb Goat before one of the pistons went out the tailpipe. It's surprizing when you have something sucking real hard on a carb how much more they flow.

Greybeard,
How long ago did you build the corvair carbed turbo setup? Sounds like it did what you wanted.

I like the Mopar story. Tom

Tom,

The one in the pictures is the one I had in the classifieds and sold 2009. I'm sure it would have done just what I wanted, however I decided I wanted multi carbs and installed a Charlie Price pair of Strombergs, one primary, one secondary, with his two into a 4 barrel adapter, using the offy manifold. I picked up a tricarb Offy manifold and I'm going to mill the top down and make a four carb top and use the 140HP Corvair carbs. The center two will be the primary carbs with the end carbs being secondary.
Have you started to play with the Pontiac unit yet?

I was considering a draw through setup a while ago and wanted to run a side draft of some sort.

I came across a place on fleabay that was selling 52mm side draft Webbers, IIRC someone had an adapter to put a DCOE on the front of a turbo, not that it would be hard to fab.

Food for thought, as the lower the restriction before the turbo, the less heat it builds for a given boost (within it's design limits).

Also, as the intake restriction before the turbo is less,the turbo will spool up faster.Also the same goes for the exhaust system.


MBHD

"I know all about the early Nova's bad suspension" --that sounds like a Camaro guy's line!
They were no worse (nearly identical)than early Mustangs. Put in some '64 or later a/c springs and some station wagon mono leafs and they're ok 'til you try to stop 'em. Now the '64/67's used Chevelle sized brakes and five bolts as did the laterbodied corvairs-- you can also put in 'Vette worm nuts to quicken the steering ratio (more effort though). You Camaro and '68/later nova guys had it made!

[quote=edski They were no worse (nearly identical)than early Mustangs. [/quote]

And those have great suspention?

Later model Chevelles,Nova etc, all had crap for brakes if they had drums all around. Ok for a grocery getting ,but not for street racing for sure,I would make 1 pass & brake shoes would be toast,& that was when my car ran 14's & short shut down areas.

MBHD

All true.

I had Greybeard's story in mind though about how much a turbo can draw if it had to, and engine damage resulting.

I'm not knocking him, nor am I saying the engine would have survived the boost levels if the charge had been cooler, just throwing it out there for those that might not be aware that undersizing the carb has more issues than just power reduction.

When I put that unit in the pictures together, I already knew it wouldn't be a drag car, and only see boost for very short periods of time. The Buick unit boost control limits it to 7-8lbs of boost or about 50% more power available. A potental increase of 70HP over a stocker. When a too small of carb is used it will go fat as it draws more, and fat is safer. No, it's not for the strip or Bonneville. Been both places and know better. I was trying to build it the way the factory might, simple and not requiring engine upgrades. FYI. I built a Roots blown small block and took it to the dyno to make sure the fuel curve was OK. I unhooked the link between the primary and secondaries on the carb and we did the primary alone. EGT climbed to about 1350 and then dropped back as we approached 5000 rpm. At 6k it was down to 1200. The same thing happened on the secondary as we opened just them using a piece of cord. When both were working the EGTs Went to nearly 1400 and then began to drop. When too small of carb is used it will go fat and EGT will drop. It wont have the same power potential as a bigger carb, but I wouldn't go so far as to say that it wouldn't be safe. Just not up to the power potential of the bigger carb.

From my experience with nitrous and superchargers in the 5.0 Mustang realm, EGT's at or above 1250 is dangerously close to melting pistons and valves. Hope you haven't damaged anything.

Greybeard is giving a example of a engine he put together many years ago. He has since sold these parts.
He is just trying to give a easy example of how to cheaply turbo a inline. And get a reasonable gain.

Another quote.
"The color is Evening Orchid. One year only, 1965. It is a very striking color in person. The car has 1966 door panels, 65 tail lights, '66 exhaust grill, '66-69 front nose bar, Corsa instrument pod. It looks to be very well done and I bet the car is beautiful in person. Very nice job he did."

Is my Corvair expert friend correct?

MBHD

Hank said
"And those have great suspention?"

Ed says
Well Shelby and the Group 44 guys did put a little pressure on the Penske/Donahue team during the Trans-Am days with their "great" collective suspensions.

Hank said
"Later model Chevelles,Nova etc, all had crap for brakes if they had drums all around. Ok for a grocery getting ,but not for street racing for sure,I would make 1 pass & brake shoes would be toast,& that was when my car ran 14's & short shut down areas."

Ed says
No- no, the real crap brakes were on the four lug Corvair and '62-'63 Chevy lls--one road test recorded 60 mph to 0 in 194 swerveing feet (thats 12-'54 chevy car lengths). And when you're fresh outta '54 Chevy, a 12 volt starter and an "instant on" transistor AM radio its a very good trade (note-I did'nt say stereo, reverberation, cassette, or even 8-track).
For gymkana racing, Chevy ll owners had to find a station wagon just to see what a front sway bar (5/8" dia) looked like. But down the lane at the local bone yard was a blue oval (oval is also a four letter word) Mach 1 with an easily adaptable 15/16"dia front bar, anna flimsey 1/2" dia rear bar.
My Chevy ll buddy had the mach 1 front bar and home made a rear bar from a piece of "stressproof" 1" dia rod. It was a simple link type setup similar to most front bar set ups. With heavy duty monkey ward's shocks all 'round, and some home made short third, or steering arms (a Corvair trick)for quicker steering, my buddy stepped out into the gymkana circuit.
Gymkana racing was not as finite as drag racing in those days (1974ish)and lumped all non-Cadillac domestic cars together. His powerglide 194 possom motor (equipped with a legal 194 head) six banger, 3.08 posi(also legal), and E70X14s gave no handicap to the Camaro/Firebird boys be they Z-28, or Trans-Am versions. It had to be tough on a new Z-28 owner to see and HEAR the split manifold RAAAAP around the course locked in low range especially when its better time is announced. Trans-Am owners didnt feel the sting, something about that 261 (thats a good Chevy number) cubic inch advantage.
As I've said before, Camaro owners had it made!
But what this has to do with the original thread is beyond me- and true to form I tried not to let facts or protocol affect my story! Oh yes, I remember, this is what you can do if you're stuck with a '62-'63 chevy ll, '64 and later owners dont even have to redrill their hub/drums for the neater wheels (they sort of have it made too!)

Your friend is pretty sharp. The car is/was a '66 Corsa. The paint, Evening Orchid or Iris Mist if you were a Pontiac guy, was a one year only '65. I'm pretty sure the guide # on the taillights are '66, but won't swear to it. What may be throwing off your friend is that the inside lights on OEM setup are backup lights, and I have replaced them with a second set of tail lights. But good on 'im. The car was at first only to be my "wallhanger" at the back of the shop. However, through the 15 years I've owned it, I;ve used it as an escape when the PMS and menapause atmosphere made it too dificult to remain in the house. It is a great driver, and quicker than snot. Without the front facia cut up, the back seat in place, and the color, it is a very stealthy piece. I love it and have owned it for 15 years.

CNC Dude
Before we took the engine off the dyno, I had fattened the carb considerably. I was showing how the fuel curve changed when the venturies are really challenged. They were way too high when the carb was working on all four barrels, not so much on just two barrels. I like an engine to be real fat under boost to cool the combustion chamber. It reduces detonation, the real bugaboo in longevity.
My last hydro was powered in one class with a legal "stock" engine, 7ltr div.11, and when equiped with Nitrous ran 7ltr div 1. It was the World Record Holder in both classes. I set up the "stock" engine on the dyno at 1320-1350 hottest cylinder for EGT. It was difficult to get accross the board same temps as I was forced by the rules to use a stock manifold and when I was done the carb had different size jets in every hole. I set up the Nitrous to 1150. That was 35 years ago with a Marvin Miller Nitrous system, good for an instant 200ft lbs.

The reason I am showing the Turbo is to show what you can do on the cheap. I bought the rebuilt turbo along with a rebuilt q-jet for $135 dollars. The Carter carb was $200, the piece of material for the adapter was about $15. Exaust mods $25 in material.
On my Elco I have Langdon's headers, $200 with shipping. Another $200 at the exhaust shop building the duals. I paid $200 for the Offy manifold, and $135 for a new NIB Holley Webber 4 barrel carb. With the misc. parts I've probably got $800 in exhaust and intake compared to a cheap little turbo, a small safe little carb, that will nmake more power for half that. I could cut that price in half by using the Q-jet, but they are so ugly compared to the Carter.lol

Tales of brakes as long as we're off topic a little.
In '67 my best friend and I bought each Camaros. His was an SS350 and had drum brakes. It was a dog. I had a set of 4.10 gears, and we went down to Chevy and got an L79 cam. After installation we went out to test it. Our test site was 1/2 mile long with a 35-40mph corner at the end. I ran his car through the gears and then got on the brakes hard at the end, stopped and turned around. I ran it hard through the gears going back and another hard stop. Turned around and said I wanted to try more revs. Well, I only had brakes down to about 70, but good pedal. By downshifting and pushing as hard on the pedal as I could, I spun going through the corner, and was blessed to keep it out of the ditches. Those brakes were toast.

I'm of a different line of thinking here, I'll post my thoughts under these two posts. Set me straight

"Originally Posted By: NexxussianFood for thought, as the lower the restriction before the turbo, the less heat it builds for a given boost (within it's design limits). "

"Also, as the intake restriction before the turbo is less,the turbo will spool up faster.Also the same goes for the exhaust system.
MBHD"

My thinking

Less restriction before the turbo, the less heat it builds? So if I double the size of the carb, but am running at part throttle, it builds more heat? That would enfer that full throttle is better than part, as a small carb wide open or a large carb only half open would flow the same.

The same question goes with the "spool up faster". Ever put you hand over the end of your shop vac. Does it speed up, or slow down when you restrict the flow.

In the end, total power is restricted, a good thing when working with a stock engine internals, and that the small carb goes fat reducing the intake heat through vaporization, combustion temps are reduced which reduce detonation, and exhaust temps go down when the engine is rich as well. Lean=hot, rich =cooler.

I stated,when using a less restrictive say a filter before the turbo,the turbo will spool up faster,take less time to get into boost.

MBHD

When the throttle isn't wide open the carb size is irrelivent as the throttle is the limiting factor.

You can undresize the carb to act as a limiter, IIRC there used to be a comercially available limeter that did the same.

If it were my engine however, I would prefer to set the wastegate to limit the boost to a reasonable level for a given engine, rather than choke off the turbo.

As for the shop vac speeding up, that's because the vacuum impeller is not driven by any function of the airflow coming in the hose (being driven by an electric motor it will run as long as current is available).

Try holding your hand in front of a blow drier, feel the amount of heat.
Now restrict the back or "intake" of it and feel how much hotter it gets.
I'd imagine the same happens when restricting the intake on a turbo.

One thing I love about our passion, each of us is free to do things our own way. Even through the years I've changed my approach to things from WFO to being more concervative. I go to car events and marvel at the novel/new approaches to doing things. However I tend to appreciate simple and well thought out, to price is no object 21 Century gizmo infested equipment. My son appreciates the latter.
My approach for the turbo was based on having used that model turbo in two other projects, and many hours of testing and playing with it. I found the turbo, which is quite small actually, was not meant by Buick to make their cars dragsters, but to boost the low end without effecting economy. If one was looking for just Horsepower, you'd look for a bigger unit that came slower, but harder up top. Even on the 225 Mopar, it was on the wastegate before 2000. It was easier on it to see when it reached it's 7.5 as the mopar had a stick. When I istalled it on the 250 it was on an automatic with a looser TC. It would light the tires in an instant, and the needle on the VDO gauge always looked like it was directly connected to the throttle pedal. Anything that quick in a turbo is leaving HP on the table. The 225 used a single 2" throttle propane carb. It had more than a 50% increase in power over NA propane, and perhaps had a little bit more in it but it started to lean out as it approached 160RWHP. The Chevy proved that a small gas carb, a 2" SU, could make some pretty big HP as it attained 16lbs of boost when the wastegate was disabled. We needed to put a lot of water in it when we did that to prevent/minimize detonation. Using a larger carb would have not helped much as the compressor inlet in that turbo is only 2". When I chose the carter, I knew it would flow less than the SU, simply because 1 7/8" is smaller and the SU actually flows better for throttle size than a venturi carb. The Corvair 1st series of YH carbs was rated at 170 cfm. I couldn't find a rating for the last series, but at 1/8" bigger, it would flow better. Figuring that engines generally work at about 70% volumetric efficiency, a 50% power increase would represent 105% volumetric efficiency. 200 CFM at 105% is about 23-2400 rpm in a 250 L6. Knowing that it would be on the wastegate well before 2000 we know that the small carb can supply max torque. As I was using a stock longblock I wasn't looking for 300hp. The smaller carb will go quite fat on the upper end, and that was preferable to me than spending time, money, and underhood space on some kind of water injection. Timing was to be taken care of through a Dale Engineering vacumm advance unit as I had used in the previous 250. KISS was the main imputous to that design. Had I wanted to turn top times at the strip, it would have been a whole different thing.

MBHD
Your friend was right about the taillights. Good eyes, that one.