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Project: 1939 Jaguar SS100 Replica Classic Roadsters, LTD. "Duke"


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OHV engine. Could perhaps drop powertrain enough to slide in.

Needs cam $400

Valve springs $100 ish? Or Port polish heads w valves and sprgs $1300

My engine uncertain origin, mileage, so new fresh rebuild or learn to do more hotrod stuff?

Or buy a running pre-hotrodded model I can also pull transmission from?

Bruce

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Based on discussion with BRD Racing, I also need to revisit the way that the Weber 32/36 carb attaches to the intake manifold

IMG_0974.JPG

This is a view of the intake manifold mounting below the carburetor.

  • There is an insert with two holes in it in pic that needs to not be there. It was part of the flow path for the original carb.
    I may have removed this part after the pic was taken or during a later stage.
  • The intake manifold needs to be ported / 'machined' so that there is a smooth flow path from bottom of carb to intake
  • The Roadster appears to have the correct adapter for the Weber 32/36 to stock intake manifold.

The bottom of the carb has the two throttle holes. The carb end of the manifold adapter has a large oval opening. The

manifold end of the carb adapter has a smaller oval opening that matches the oval opening in the manifold. I believe

what BRD Racing described is the opening in the manifold should be ported to match the opening in the carb end.

Bruce

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Based on discussion with BRD Racing, I also need to revisit the way that the Weber 32/36 carb attaches to the intake manifold

IMG_0974.JPG

This is a view of the intake manifold mounting below the carburetor.

  • There is an insert with two holes in it in pic that needs to not be there. It was part of the flow path for the original carb.

    I may have removed this part after the pic was taken or during a later stage.

  • The intake manifold needs to be ported / 'machined' so that there is a smooth flow path from bottom of carb to intake
  • The Roadster appears to have the correct adapter for the Weber 32/36 to stock intake manifold.

The bottom of the carb has the two throttle holes. The carb end of the manifold adapter has a large oval opening. The

manifold end of the carb adapter has a smaller oval opening that matches the oval opening in the manifold.

I believe what BRD Racing described is the opening in the manifold should be ported to match the opening in the carb end.

I think you are right about the smooth opening.

Anything else is going to cause extreme turbulence in the air flow.

Looks like it is grinder time and then use a DREMEL to smooth it out and polish it up ... :)

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Yup. what happens is fuel/air mix flows from the bottom of the Weber 32/36 carb, through the adapter manifold which has a larger oval at the top and a smaller oval at the bottom, then through a

double-barrel restrictor, then back to an oval intake manifold. go figure.

IMG_1314.JPG

View with carb removed. We are looking down through the converter manifold.

IMG_1315.JPG

Converter manifold

IMG_1317.JPG

Restrictor plate, converter manifold. Originally, the restrictor (flow) plate sat below the OEM carb, and sped up the velocity of air coming out of the bottom

of that carb?

IMG_1319.JPG

Intake manifold bare (except the rest of an ancient gasket needs to be cleaned off). 4.25" x 2" center posts.

The person who converted kept the restrictor/flow plate because the conversion manifold needs that spacer on the

lower studs or there is not room for the manifold (he re-used the studs, or could not get them out?)

So either I need to get the studs out and put in shorter studs, or put in a spacer plate of same thickness that matches

the bolt pattern of the base manifold and the oval pattern.

Bruce

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Dremel with grinding tool, meet restrictor.

IMG_1325.JPG

This is an 'after' view down the rabbit hole through the 32/36 conversion manifold and into the intake manifold after I port-matched the piece below the conversion manifold.

I am missing an OEM toyota gasket, the one that previously was between the intake manifold and the piece I just ported. (a gasket that tore apart / dissolved on dis-assembly)

ALthough I put everything back together, the car will catch and run when I give it gas then die, so I think I have a vacuum leak in the stack -- I suspect I need to clean up the

intake manifold surface more, and I need that missing $0.39 toyota paper gasket. I will probably have to make one to fit, but we'll see what O'reilly can help me figure out.

Bruce

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If you cant find one... get a thin piece of gasket material, a SMALL ballpeen hammer and an Exacto knife.

Lay a piece of gasket material on top of the studs.

Gently tap on them th make impressions in the gasket material.

Cut out the holes with the Exacto knife.

Now lay the gasket material.on the manifold, with the studs going thru the holes of course, and gently tap all around the center hole.

Take it off and turn it over and cut it around the lines.

And there you have it ........ a new gasket... :)

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Okay, I did my kindergarten best at making gaskets at home because it amused me to do so and the hope to get it back running.

After studying suggestions on the net I went with a light card stock (file folder) material. Thick paper bag would be ideal, but

this material has some sponginess and I have plenty of it.

IMG_1328.JPG

IMG_1329.JPG

IMG_1330.JPG

Took it all apart, and could see some seepage signs along the non-gasketed side of the restrictor plate, a good sign.

I put in the new gasket, then put it all back together. Still same result which seems like a vacuum leak. I'll keep working on it tomorrow; seems like something simple to be fixed.

Possible that the carb also needs a start-over tune due to the difference in intake stack, but this seems a dramatic issue so I am thinking intake leak.

Symptom: car won't start without giving it gas. Will stay running if you keep fluttering the gas. If you get off the gas or hold the gas steady it dies. That all sounds

like an uncontrolled source of intake air to me, so either new gasket not sealing, or bottom gasket not sealing against the intake.

Bruce

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You can get a variety of gasket materials in bulk sheets at an auto parts store or even many hardware stores. Example:

http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Gasket-Material-Karropak-Pliable-Chemically-Treated-Fibrous-Sheet-/_/R-FPG3023_0417989940

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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Good; thanks Jim. I am guessing I need to clean up the previous gasket completely

and I will redo the homemade one.

Bruce

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Good; thanks Jim. I am guessing I need to clean up the previous gasket completely

and I will redo the homemade one.

Like Jim said... almost any parts store will have the gasket material.

Another gasket link..

http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=gasket%20material&sprefix=gasket+%2Caps&rh=i%3Aaps%2Ck%3Agasket%20material

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Agree. Placed an order on amazon yesterday for thurs just in case.

Rebuilt the stack after more manifold cleanup no diff except I think my paper gasket is whistling.

Read another diy howto guide that said what I did works ( unless for a carb manifold gasket) lol

I am getting better at pulling off the carb

Bruce

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Agree. Placed an order on amazon yesterday for Thurs just in case.

Rebuilt the stack after more manifold cleanup no diff except I think my paper gasket is whistling.

Read another diy how to guide that said what I did works ( unless for a carb manifold gasket) lol

I am getting better at pulling off the carb

That was why I suggested GASKET MATERIAL in my previous post.... LOL

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Ok, we have carburetion and Air/fuel control.

Ran by O'Reilly's for a gasket scraper (carbon remover) and gasket material. They had 3 types, none of which were exactly what I wanted.

But I got the most likely.

IMG_1331.JPG

Made the new gasket, put it all back together, and same problem. Car would run 20:1 or 22:1 air/fuel and die,

clearly getting too much uncarb'd air.

Used the scraper to work on the intake manifold old gasket remains of the remains. This tool worked terrifically.

Very easy progress. Examining one of the existing gaskets, I had doubts about it, so I made another new gasket.

IMG_1332.JPG

I went through every surface in the stack -- carb bottom, gasket, conversion manifold top, conversion manifold

bottom, gasket, flow director, gasket, intake manifold. The conversion manifold had some residue that easily

cleaned off but may have contributed.

Put it all back together, and it idles! Was a bit lean so I richened it up some.

Ran it around the block and first impression is high RPM revving will be improved. I need to start over

on noting the air fuel ratio at each point in operation and perhaps will need to rejet.

Bruce

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Drive Video; forward to 6:25 to hear acceleration run after turn from stop to ~45 mph

(just loaded to youtube so will take a bit to process

 

Didn't turn out as well as hoped but gives an impression.

Bruce

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Quick test run this morning 57F. Car is running significantly too rich at low throttle, and began to run very rich at idle.

Also rich at WOT; Current jetting is 150AC160 / 160AC185. Looks like it may be ready to go back to 130AC160 for mains.

Run num Speed(mph) Time(s) Dist(f) Graph run Description

3 0.00 0 0.00 Speed Start
3 10.00 1.04 8.33 Speed Line
3 20.00 2.64 44.40 Speed Line
3 30.00 4.68 119.15 Speed Line
3 40.00 6.80 228.23 Speed Line
3 50.00 9.53 409.58 Speed Line
3 60.00 13.84 757.64 Speed End

Previous:

3 0.00 0 0.00 Speed Start
3 10.00 1.12 8.64 Speed Line
3 20.00 2.50 39.54 Speed Line
3 30.00 4.29 105.40 Speed Line
3 40.00 6.32 210.53 Speed Line
3 50.00 9.08 394.27 Speed Line
3 60.00 13.02 712.19 Speed End

2013-09-25+Intake+Changes.jpg

Red is previous; blue is today's run. Curve looks like the same flat top shape as before -- no improvement there, and less HP overall.

That may improve with the correct jetting. Certainly not the result I was hoping for, but this is why I test.

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oh, and the choke was unplugged again, so the previous run is suspect. When the choke is unplugged, the car stays choked with the butterflies closed, especially in the cold morning air.

Tonight I added a Blaster II coil instead of the toyota OEM coil; BRD Racing suggested the type of OEM coil I have is suspect at higher RPM.

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Did a cold air drive this morning. Once the electric choke warmed up the engine ran correct afr's. On return I visually checked and the choke butterflies were wide open. At idle after drive afr climbed back to expected 13.2+.

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[sorry, I got the whole story in then realized I had the wrong results -- updated now]

Retest intake mods, plus jetting 150ac170, 160ac190. Same picture, different day.

More torque up front but no effect on peak HP.

Run num Speed(mph) Time(s) Dist(f) Graph run Description

2 0.00 0 0.00 Speed Start
2 10.00 1.10 8.38 Speed Line
2 20.00 2.61 42.36 Speed Line
2 30.00 4.49 111.37 Speed Line
2 40.00 6.56 218.06 Speed Line
2 50.00 9.32 401.50 Speed Line
2 60.00 13.40 732.92 Speed End

Comparison+choke+fix+to+new+jets.jpg

Red is today, blue is a run prior to flow restrictor port matching and jet changes. The blue run showed 68 hp at 56F with NO temperature correction,

but corrected for temperature it shows as 65 whp.

With the leaner air correction jets steady state part-throttle cruise is up at 13.x-14:1. Light throttle is too rich, suggesting the idle jet is too big.

WOT leaned out to (not sure I was holding on at the time).

Temp in 90s for today vs low 60s on some test days, but basically we have the same result and curve. 64 whp today, for 80 hp at the crank.

Our high so far has been 68 whp, low 56 whp. My impression is the car liked the smaller air correction jets.

The Choke Fix run had 150ac160/160ac185. I like the leaner AFR's with the current jetting but the car may prefer to be richer at WOT. O

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offenhauser+intake+for+3tc.jpg

Offenhauser 3TC intake manifold info / claim -- 22% hp improvement

K757-2.jpg

Weber 40 DCOE twin carb with one throat per cylinder, direct flow manifold from Pierce Manifolds

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Ran back to back initial timing tests today. First I set the timing to 15 BTDC, and tested. Then I reset the timing to 7 BTDC and tested.

Finally, I reset to 10 BTDC and retested. 84F / 29.96 baro

15 BTDC 0-60: 13.85 sec (some vibration at idle)

07 BTDC 0-60 13.88 sec

10 BTDC 0-60 13.63 sec

So it seems happiest at the 10 BTDC. Next I want to go back to 150ac160 and 160ac185 instead of current 150ac170 160ac190

The 10 BTDC and 15 BTDC had identical Virtual Dyno curves; the difference in the runs was after shift.

The 7 BTDC lost 8 ft lb of torque up front.

Bruce

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Changed the jets back to 150ac170 160ac185

Apparently the retaining bolt on the throttle linkage on the 32/36 was cross-threaded, and now the threaded rod that is a core

part of the main throttle valve, power pump, etc is stripped. Tomorrow I will take the other 32/36 and see what the thread

count is and if I can find a chaser. This is an odd bolt that is oblong, and only threaded on the round ends.

It should not have to carry any torque, as 32/36 throttle accessories are 'keyed' to the oblong shape of the bolt,

but the toyota throttle linkage was not. It has a round hole. So the bolt has to be on tight enough to keep the toyota

linkage working.

Actually, perhaps the round hole toyota linkage riding on the bolt actually acted to squash the threads? So needs the proper

linkage.

The car is not drivable until fixed. Researching, may need (another) 32/36 and (I have ordered the) proper linkage.

I will also look to order another bolt from OEM. Meanwhile, 40DCOE looking better and better lol. I mentioned this to BRD Racing

when I called to ask about repairing my 32/36. They said no point in putting a sidedraft carb on unless engine fully built.

So, I'll take the bolt and discover the thread count and get a chaser. if I can't chase the threads on the carb I'll order another

32/36 and write it off to learning.

Also sent for one of these air horns for the 32/36 carb -- the curved hat part at the top.

imag003.jpg

Which theoretically improves the flow of the 32/36 and will keep the choke and will fit under my filter.

There is a Velocity Stack / Air Horn for the 32/36 by Pegasus

3890.JPG

but it requires removal of the choke, and sort out a filter for it.

Bruce

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The 32/35 has velocity stacks of a sort, just designed for an air cleaner and a street car. The Offy/DCOE setup is an obvious racing setup, with the "manifold" just setting the length of the velocity stacks that include the DCOE thoats and horns, which places the resonance of the intake stacks. You can approximate the RPM of the resonance by using the speed of sound in air (343 m/s or 1242 ft/s at sea level, 68 F), the length of the stack as 1/4 wavelength, and the frequency is 1/4 the RPM. Ten inches or 25 cm puts the resonance at about 5,000 RPM.

I think that you will absolutely need a cam and heads to get any advantage of the DCOE setup. Running cold will not be an option; you will be squirting priming mist into the stacks until the car is warm enough to run without a choke.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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Before I bought a whole carburetor, I would take the pieces to a machine shop to fix - or duplicate.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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