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I am about to start on a rebuild of my Seville STS.

The items to be done or redone are as follows.

I have an extreme stress job all mental so build the next two cars is my physical release of stress.

To start with I have a blown gasket and a collapsed lifter. My spouse continued to drive the car and cracked the transmission cooler in the radiator flooding the engine with trans fluid and the trans with coolant. So pretty much toast.

I have previously upgraded the brakes with Stage III Power Stop rotors and pads works nice but after sitting they require resurfacing. I will be making a polisher to do this as in my home state service providers are afraid of recutting rotors especially when they are drilled. Back in the 1980s I worked for GM as a DCS tech and forensic specialist out of Corvette Action Center and PRO. We had severe issues in Florida with the early Lumina brake systems warping rotors and chattering I designed a KentMoore tool similar to the Jaguar inboard brake resurfacer it uses #m polishing pads rather than cutting bits to resurface the rotors on the car. Pretty simple device bolts to the brake caliper mounting flange  and uses air motor right angle grinders with spirolock pads.

I have a couple of body issues one is the drivers side back door welt is rusting through under the welt so I will document how to do a simple resign repair, not bondo but epoxy.

The roof channels have leaked on the electric top since I bought the car new. I am removing the electric roof completely and replacing with a simple after market sun roof with lift out panel. I will be trimming the interior to fit with factory styling.

Because of the roof leak I have several issues in the interior one is a pretty bad case of mildew. Having restored flood damaged cars in the past I intend to use a Ozone generator to bleach the whole interior for several days. The factory material will be placed with flocked marine canvas and composite leather cloth. I found a great manual shoe stitching machine on Amazon that does a great job at sewing leather. I converted a L91 Caprice police car to a G body Fleetwood interior a few years ago was my main driver for 8 years. The interior stuff is always fun because GM tried to provide common tooling for many of it's vehicles and most mountings are common across many car lines. Not really happy with the Dash on this model I will be building a custom gauge cluster and navigation center using standard desktop PC components and linux open source software.

The seats are functional but need leather replacement and due to my illness my back has a tendency to tweek on hard turns so I will be setting a pair of racing buckets into the build. If people need seat parts I will have two working units available.

Since the roof leak was mainly in the drivers side A pillar the electrical seems to have been damaged so not bothering to repair it I will be replacing the whole thing with a new custom harness.

The suspension was upgrade a few years ago with all new urethane bushings and aftermarket shock absorbers with level ride maintained I will document that process for the build as I will be removing the factory magnaride completely and replacing with a simple arduino based controller. This model of seville squatted nicely when over 90MPH and the ride stiffened greatly the after market struts have air ride built in and are actually stiffer so I have in mind a air valve control that will squat the car and keep it stiff all the time. 

The engine carriage mounts have already been up graded to urethane and HDPE I will document the process of making the mounts it is actually pretty simple.

I paid someone to replace the transmission when I became ill thinking that I would bounce back quicker than I have so I will be building the jack and stand system to drop the carrier without the over head lift. Once the front body work is removed from these chassis they easy to work on. Many struggle needlessly to avoid dropping the carrier. A couple of weld up scissor stands and a porta power will get the car 36 inches off the ground lifted from the body welts on the sides. The carrier comes out as you lift the body with a weld up dolly it takes about 2 hours to pull the whole assembly.

The transmission is a simple bent version of a 4L80E same parts mostly with a heavy chain. The differential will be upgraded to a mini locker like the ones used in the 7 5/8 rear of any GM they cost about $250 it makes some noise when making sharp turns but for HotRod use it stops the crazy unpredictable torque steer when accelerating hard. The week point on these transmissions is the 3-4 apply band and housing the after market has case repair kits for the GMC K series trucks that work in this trans. Another company TCI makes an upgrade kit for sprags and drums clutches and all for the 4L80E that works in this trans. I have not seen a decent High Capacity oil pan for this so I may need to weld one up. The front pump is essentially the same as a 4L80E so I will pick up a stahl convertor once I figure my torque peek.

My engine has suffered the dreaded over heat than code 300 sporadic miss for years WOT usually cleared it out but after the last run it has an audible noise that matches the miss. Compression is good so I think it is probably a collapsed hydraulic cam adjuster. If it is a core shift in the head I will be documenting how to weld the bore and rebore a new. I am also planning on putting a turbo on this build or maybe a M122 eaton I have to get and accurate pattern for the difference between the XLR heads and the STS heads if there is a difference maybe someone hear knows. I will look at machining the adapters if practical if not turbo it will be. I plan to redesign the exhaust manifolds for this car either way the rear one is basically a modified log manifold. So if I go turbo it will be a mandrel bent log style manifold with a scavenging front pie wedge triY setup. 

The block will be either timesert or I saw a guy who makes larger studs for these engines I will inspect once apart and determine what course to take. As I am going to boost the engine I plan to add piston bottom oil cooling to help prevent lean burn through. Used it on many of my previous builds using diesel engine main bearing squirter inserts it works nicely.

As I am boosting and planning on running at Higher RPM I will be looking at methods to stabilize the lower block main caps I can machine steel 4-6 bolt caps or simply girdle the whole bottom of the block I have to look at the webbing in the casting to determine whats needed.

The pistons are pretty good in these motors is the originals still look good I will lighten them up and plate the tops with nickel the skirts will be coated with Tungsten Disulfide as I have about 4 Kilos of the stuff in my one blasting cabinet. I may select some after market rods once I get some accurate dimensions for them PCE in Australia has a bunch of nice H-beam rods that I have modified for strange builds in the past.

As for the electronics I will be using my own fuel management system I have a couple of threads on other forums covering the fuel systems I have built.

My Goal is to produce about 750 crankshaft HP dropping the car down into the 12 second realm. With a mild street presence.

To do so either the M122 or turbo intake manifold will change so I may lower the engine in the cradle or put a cowl on the hood.

It will be a fun build I will keep lots of photos and probably some how to videos.

I figure about twenty or so commercial products will come out of this build so it will get rid of my aggression and please the wife on Total cost involved.

This is my 50th year of Heavy automotive engineering and actually still love building hotrods.

Also this is my 17th Cadillac Hotrod starting out with a 472 powered 1972 Chevy Impala with a complete funeral car Caribou interior and trim transplant. Tubbed rear wheels before they became cool. My favorites are the 9 Cadillac Cameros for racing. The guys called the Cadillac motors boat anchors but they started out over 300Hp and with shipyard blowers hit 700-900 easily.

Look forward to having some fun.




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Started Designing some of the Tools for this Build Today Happy Easter.

As I weld and I am an advanced fabricator Machinist engineer type. 
I wanted to do this build out of my home garage however My race car sits there so I am building in the driveway under a big Live Oak Tree.

Message me for the sketchup file it is just over 207K zipped.

So this is a design for the body lift based on a hydraulic ram driven Rhomboid with telescoping rear supports.

To use I plan to first jack stand the car wheels off and slide under the body, clamp the pinch clamps to the body jack seams and using the porta-power pump raise the front bumper of the car to about 40" in a clam shell opening rear lower front swinging up motion that makes it easier to detach and reattach the carriage. I will be designing and fabrication a carriage dolly that will index off the rear mount like the factory build line install JIG. At The factory the body comes in from above and tilts at about a 15 degree angle as the bottom carriage  shuttle joints index on big pins and then merges allowing the four corners to be bolted easily.

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Hydraulic cylinders 992207.pdf

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I f any of you guys have a set of the Cam bearing index tool from Kent Moore 6686 I would love to get the measurement of the two plate tools. Gap and distance.

If I pull down the motor before the measurement I will make the tool by measuring my engine and post the drawings here.

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Started the engine tonight after sitting for 2 years after charging battery started up with bad miss.

I will be repositioning the car in the drive in the morning and covering with large tarp to start disassembly.

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  • 4 weeks later...

Flipped the car around and got distracted with another motor build finished up Wednesday.

It was pretty fun the guy has a 1977 lasaber with a 1950s style Mexican tuck and roll leather interior completely in purple with white stitching not my style but absolutely beautiful.

The tear down on his junk yard motor revealed a 1980s top of the line 355 build.

2256 pistons lightened rods ,internally balanced rotating assembly, old big valve smog heads. Measuring it was great everything was done to the style in 1984.

Back at that time I raced Nascar and some of the old tricks have been done to this motor. 

To lower rotating stiction and friction top builders would bore the cylinders with a few thousands taper tight on top of stroke loose on bottom.

The block was decked down allowing the top land of the piston to be out of cylinder by .030in then they used old perma torque .070 gaskets to space the quench area perfect. Cam bearing journels on the center three had been oversized to true a shifted cam bore after the cylinders had moved with seasoning. 

Four bolt mains non splayed steel caps.

Pan skirt milled down .025 for old style block girdle.

Screw in rear cam plug pinned freeze out plugs.

The heads are smog heads with 119cc chambers un relieved intake ports not matched, bronze sleeved instead of bronze guides. oring seals no umbrellas.

I built the motor back a little different.

I chamfered and cross drilled the crank oil holes,

 Fit Total Seal Zero gap secondaries and Ductile top rings pistons and block only needed minor cleanup.

I used a .040 stainless ringed graphite head gasket.

Heads I milled down the valve guides for modern teflon silicon seals and to allow larger lift.

Cleaned up the shortside radius on intake and exhaust ports, tear dropped the guide bosses in pocket, ground a tulip on the valve head to stem transition.

Cleaned all of the sharp edges out of the combustion chambers and unshrouded the valve to pocket to 5/16 all around. Matched the gasket on the intake ports opened up the pushrod holes to 7/16 holes, removed the 3/8 studs and installed 7/16 with stainless cast 1.6 roller rockers. Valve springs open at 380LBS closed at 200lbs.

Set a Stage 3 cam .496 lift 305/290 duration 108 at 103 centerline.

Motor sounds solid should make 375HP at the wheel.

I will post a video on starting it on the floor.


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So today I was doing some calculations on the upcoming engine build.

I have a desire to avoid using 100 octane or 110 because of the price.

I am looking at limiting the effective compression to 13:1 and using water ethanol mix to suppress the charge temperature further so that the initial combustion temp is under 760 avoiding ping.

I am thinking of setting up a sequential turbo so I do not have a steep slope on the power band.

Small 1.8 2.5 L .63 Trim VW turbos are less than $150 while the larger GT45 are under $200.

I found the exhaust manifold flanges.

This guy has them for $50 http://www.vendio.com/stores/JAYNIMMO/item/racing-parts-exhaust/cadillac-northstar-v-8-header-/lid=2555777

 I am most likely going to use a trick I know to use scavenge fuel pulse waste spark to keep the exhaust lit in the manifold increasing and maintaining turbine speeds.

This requires some heavy gauge header pipe to avoid burn through. I have used RIGID electrical conduit for this in the past it works fine you have to soak in muriatic acid to remove the galvanizing, weld it then bake it in a kitchen oven at 575 for an hour. Take out put in a box with damp rid until cool to touch. Spray bomb the whole thing with rustoleum 2000 degree then while still wet put back in oven at 190 for two hours ,take wife to dinner when you get home turn the oven up to 575 again. This removes any chance of cracking and gives a durable finish inside and out.  This will cure out on the car over a couple of hard pulls you need to wrap the whole thing in titanium heat web header wrap. They last longer than most stainless headers and cost is cheap.

So I am placing the turbos in the drivers side forward removing the air cleaner housing the hot side tube routing will be front to back then two turbos at the crossover. The small turbo feeds the big one through the waste gate and turbo outlet combined. One half the GT45 turbine is fed from this pipe the other is fed  from a second waste gate set at 2.5lbs of exhaust pressure looking at the GT45 it is set up with two turbine stator housings and inlets one outlet. So little turbo with big waste gate  set to 6psi intake pressure turbine outlet into one half of GT45, Second waste gate on crossover pipe feeds second turbine on GT45. Inlet of small turbo draws from air box. Outlet of small turbo blows into second half of air box, Inlet of second turbo draws from second half of air box air box has a plate reed valve set at one psi vacuum that separates the two sides. 


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This staged method allows use of smaller fast start turbo to produce pressure off idle to about 2800 rpm giving time for the second larger turbo to spin up and carry out to 9000RPM the two turbos are actually smaller than a T70 that would be good from 3000 to 9000. But there is little or no turbo lag or steep boost transitions. I did some thing similar on a BMW 633 with a 3.5L and one 1L and one 4L sized turbo.

The transmission will handle the added torque and RPm no problem but I will be putting another cooler farther back in the car due to the high likely hood of very high front pump pressure. I already experienced the in radiator trans cooler failure and placed a new transaxle a couple of years ago. I put a Large Aluminum TANKED RADIATOR IN AT THAT TIME.

I am still determining the location of an intercooler I might go ahead and put a cowl induction style scoop on the hood and dump the heat out the top rather than put it before the radiator there might also be enough room to place the intercooler between the trans axle and fire wall and duct it down.

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Another aspect of using the water methanol injection method of detonation protection is the amount of time that it takes for the water to evap drawing down the heat of the combustion charge. on a twin turbo ford 5L I built a few years ago I found that the sweet spot for the extra injectors was 19inches from the back of the intake valves. So that gives me a good volume reference to use on this build. I was pulling 1048 HP at the flywheel on the Ford. This build I am going for a clean 700Hp.

Another aspect is this is a fun project and when complete be sold as is for someone else to continue with. I have another much faster car I have owned since 1997 in the garage waiting.

In Florida we do not have emissions testing but it is illegal to sell emissions disabled vehicles for on road use. This aspect is handled in two ways either the car is purchased as a auto rally race car as is or I can OEM the car rebrand it as a sports vehicle and provide affidavit of compliance and safety. Since the later is expensive and the audience for buying a car like this unlikely to be a non-motorhead or a purist. But a motor sports enthusiast so I will be selling it as a race car. Once you won it you can do what ever you like. 

Back during the horrible Lawton Childs occupation I placed new vin numbers and OEM registrations on more than 200 vehicles that had been built by local custom shops that could not pass emissions testing. It was later ruled in court that the State required testing was being conducted by a fraudulent company that had been thrown out of NY and paid officials in FL to enact policy that required their fraud. This ended with the state of Florida having to refund all of the fines and testing fees collected over an 8 year period. Most people came to Florida during this time and had to pay an additional $400 tag fee for out of state transfers that in itself is a Constitutional violation and punishable under USC title 18 242. 

SO after all that disclaimer I am placing a 3in Down pipe and 52 inch straight pipe then a small resonator and out to the two stock muffler tips. The resonator tends to prevent the flame shooting out from the exhaust. The sound is much loader than convention but not audible in car and passes the 85DB requirement at 35ft. Sounds more like a deep rushing sound than a pulse note.



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