Car has been parked a few years, since selling the GM Racing input shaft and 1” chain. Was originally parting out the car, and did sell drop spindles, seats and a few other parts.
Recently after seeing Brandon Furches with LS4 King put over 800 whp through a 4T80, I decided to try a one out.
Picked up a 4T80 on EBay for $200 shipped, took it apart, found the clutches still had part numbers on them. Changed some seals, bushings, modified accumulators and separator plate for more positive shifts.
Picked up a set of Pontiac Transport uprights for the rear suspension to accept the larger diameter Cadillac Axles. This change should reduce the instances of this:
Took my spare subframe, control arms and the transport uprights, and used electrolysis to clean them up:
------------------ 10.007 @ 135.54MPH. <-- Video Best 60' 1.42 Best mph 138.82 Billet 6262 Precision turbo, PT1001 intercooler, ST1 cam, 140lb springs, comp pushrods, HV3, stock L32 bottom end and heads.
Transport uprights assembled with new bearings, rotors, calipers. Subframe has new poly control arm bushings, ball joints, inner and outer tie rods.
New front crossmember fabricated and welded in, removing stock crossmember.
Mocked up spare 3800 and the 4T80. Small amount of block ear removed for clearance. (Not my pic, but same mod)
Lots of measurements and got engine and trans situated in subframe, centered for equal length axles. Built transmission mount brackets using angle iron, plate steel, rectangular tubing, poly bushings and sleeves.
These are before they were cleaned up, and painted.
Added a poly mount to the stock 3800 engine mount:
Cut some mounting tabs and welded everything to the subframe.
This mount setup is much easier to get the engine and trans on and off the subframe. It also should be a bit stiffer than the mounts I was using before. ------------------ 10.007 @ 135.54MPH. <-- Video Best 60' 1.42 Best mph 138.82 Billet 6262 Precision turbo, PT1001 intercooler, ST1 cam, 140lb springs, comp pushrods, HV3, stock L32 bottom end and heads.
Old M90 XP Cam time - 11.425 @115.60 1.543 60'
[This message has been edited by LFiero67 (edited 01-29-2022).]
Now that everything is ready as far as subframe and mounts, it was time to drop the old drivetrain out. This is the engine I last installed in 2013, has run 10.00 & 138 mph with the GM Racing equipped 4t65. It is currently bolted to a stock 4t65 that I installed after selling the race trans.
My son has been helping with all of this work, and this was the first time he has been around to drop the engine. He has been excited to help.
Mandatory standing in engine bay pic, first one for the boy.
Next steps are cleaning up the engine bay, getting the good engine bolted up to the 4T80, fit it all in the car. Looking at swapping the stock pcm for TerminatorX Max to make running the 4T80 easier and allow for better fuel tuning and stronger ignition with LS coil near plug.
I will try and update as we progress.
[This message has been edited by LFiero67 (edited 01-31-2022).]
Look up 6000 uprights on here, similar changes required to bolt in, but transport uprights also have larger cv shaft splines that match the Cadillac axles.
[This message has been edited by LFiero67 (edited 02-03-2022).]
Nice job so far but are your sure that you need a 4T80? That adds weight. Darkhorizon (Scott) on this forum and ran a 9.87 1/4 mile time at 142 mph with the 4T65eHD. From what I have read they can be built to take 900HP.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Dennis, I am well aware of what a 65 can handle. I had the same parts in mine that Scott has. I sold those parts, they are not available anymore, other than used. As I said, I am trying a low dollar option instead of the $4-5000 4t65 that I used to have.
I ran a 60 before I went to the 65. Couldn’t keep second gear in the 60, but that might have been a wear issue. The chain in the 60 is the “upgrade” for the 65. I destroyed 3 of those 7/8” chains in my 65 with the turbo before getting the GM Racing 1” chain. I also broke a 4340 and 300m input shaft before getting the GM Racing input shaft. The 7/8” chain and aftermarket input shafts are ok for M90 builds, but not with what I am making for power/torque.
I have run a 4 speed manual, a 4t60, a upgraded 4t65, and a GM racing 4t65 in this car over the last 20 years.
The 4t80 is 100lbs heavier, and the suspension upgrades will likely add another 30-50, I am ok with this.
As I stated, people are putting 800 whp through stock 4T80s in FWD applications, I am going to attempt to put 6-700 rwhp through one and see how it goes.
The car is capable of running 1.3x 60’ times, but the stock sized axles were never up to the task. 9 lbs of boost on the launch would give a 1.4x 60’, 10lbs on the launch would shear the axle. The new setup addresses this as well.
There is a chance that none of this will work, but I am going to give it a shot.
------------------ 10.007 @ 135.54MPH. <-- Video Best 60' 1.42 Best mph 138.82 Billet 6262 Precision turbo, PT1001 intercooler, ST1 cam, 140lb springs, comp pushrods, HV3, stock L32 bottom end and heads.
Old M90 XP Cam time - 11.425 @115.60 1.543 60'
[This message has been edited by LFiero67 (edited 01-31-2022).]
At this point the U-Body uprights are probably more common and the '92-'96 minivans have 11" brakes shared with LT1 Camarobirds.
Also, the A-Bodies used 27 spline outer CVs while the U-Bodies had 33 spline outer CVs. The 33 spline U-Body bearings let him drop the Cadillac axles right into place.
[This message has been edited by Will (edited 02-01-2022).]
Pontiac 6000 was available with the larger axles as well. Station wagons and HD suspension option had them. Also found on chev celebrity, and a few other cars of the era. I went transport because they were available in the wrecking yard.
Again, not so much... I'm checking RockAuto for these applications.
The A-Bodies & U-Bodies through 1991 had 10.25" front rotors and 27 spline CV joints and hub cartridges. For 1992+ the U-bodies went to the 11" and 33 spline combo.
The Buick Century was the only A-Body to stay in production beyond 1991. It appears to have 33 spline CV's and wheel bearings for 1992+, BUT the Century kept the 10.25" brakes.
The 27 and 33 spline hubs are bolt-in swaps for each other.
The 11" brakes do NOT bolt onto the older style knuckles.
A-Bodies were never built with 11" brakes. Celebrity, 6000 & Ciera were never built with 33 spline hubs & CVs.
quote
Originally posted by LFiero67: These are 95, so they have the larger brakes, with same calipers as Fbody. Unfortunately they are iron calipers, and 1.25” rotors, so it’s heavy.
Requires the ball joints and outer tie rod ends to match the knuckles, but they bolt onto the Fiero control arm and inner tie rod.
I'm not saying they don't bolt in. I've done the swap on my car. I'm saying that '90's U-Bodies have the biggest brakes and wheel bearings while the '80's A-bodies do not.
[This message has been edited by Will (edited 02-02-2022).]
Cadillac axles will require shortening to fit the Fiero Chassis. The 99 deville has the shortest ones available with the 4T80, I have not determined yet how much they need to be shortened. Others have done the longer Seville cv shafts and taken 3/4” off each end for total of 1.5” shorter.
If you look up a 1986 Pontiac 6000 with Light duty brakes, it has 5x115 bolt pattern and 33 spline outer cv joint. I owned a 1986 Celebrity years ago, and it had the larger bolt pattern and cv splines as well.
It was my mistake saying the HD brake cars have the larger splines I had it backwards.
If someone wanted the just larger splines, these cars are options, but you do not get larger brakes with the 80s cars. The LD brakes are 9.68”, similar to Fiero but vented, and lighter than the larger 10” & 11” brakes on the vans. Any of the swaps require 5x115 wheels.
FYI, the 27 spline pattern used in the A-Bodies has a larger diameter than that spline. I have the 27 spline A-body parts on my car now and the large pattern 33 spline U-body units ready to go on. I forgot that GM engineers were crack heads and used a fine pitch 33 spline on the small pattern parts.
Zooming in on that RockAuto screen cap and compare the hub end splines on that axle with this one:
quote
Originally posted by LFiero67:
Picked up a set of Pontiac Transport uprights for the rear suspension to accept the larger diameter Cadillac Axles. This change should reduce the instances of this:
Also the larger spline has larger threads, so the the larger spline is even larger than it looks compared to the small pattern spline. The small pattern hubs have small pattern splines.
The small pattern hubs and light duty brakes have 5x100 bolt pattern, just like the Fiero. This is an area in which Rock is difficult to use, as they throw all wheel bearings into the list, regardless of which engine is selected. The 5x100 bearings are universally garbage and the suppliers don't give Rock any data, so you typically can't actually look at what the dimensions of any given cheap bearing are. The light duty rotors are listed at 5x100, though.
quote
Originally posted by LFiero67:
Cadillac axles will require shortening to fit the Fiero Chassis. The 99 deville has the shortest ones available with the 4T80, I have not determined yet how much they need to be shortened. Others have done the longer Seville cv shafts and taken 3/4” off each end for total of 1.5” shorter.
Cool. Let us know how that works out. I've never looked into running a 4T80E, but it's been done with plenty of Northstar swaps.
Used my wife’s cricut machine, with her help to create a template to locate the 4 torque converter bolt holes for the 4T80 converter. The line on the template aligns with the Center of it the counterweight, and puts the holes equally on each end.
Drilled pilot holes at the locations on the template, then drilled each hole to fit the m10-1.50 bolts. I purchased bolts for a VW Caliper to Knuckle Mounting from Amazon: https://www.amazon.ca/M10-1...Grade/dp/B07PRG68MZ/ They are a bit too long and have a unthreaded portion, so I cut them down and ran a die down to the head.
Trial fit the torque converter, and it bolted up with just a little wiggle available. Reduced head socket bolts are flush with the counterweight so there will be no interference with the engine.
Relocated the rear knock sensor, cut the ear off the block and got the new engine mount installed.
Have to get a new gasket for the oil filter housing, then it is ready to attach to the transmission.
[This message has been edited by LFiero67 (edited 02-03-2022).]
I guess the converter pilot works and/or is compatible. Are you going to put an indicator on the pump drive and roll the engine over to verify concentricity?
[This message has been edited by Will (edited 02-03-2022).]
Checked offset of a 3800 flexplate relative to Caddy flexplate?
I don’t have the measurements for a northstar.
Converter has 0.094” of clearance to flexplate when fully seated in transmission. RWD GM stuff is supposed to be 1/8-3/16”, so I’m a little under that, but it is a number I’m comfortable with.
I've had a few conversations with Brandon his build. He said the only issue he's had with his 4T80 was the first one chewed itself up due to a long 2-3 shift. He flipped the 2-3 piston on his subsequent transmission and hasn't had any issues since. Not sure if you have done that or not.
Also, Will, I did not realize that there were fine splines vs 'standard'(?) splines! How do you go about finding this information? (I want to make sure that the axles I'm going to be ordering don't just fit, but fit properly - sorry for the slight high-jack).
I've had a few conversations with Brandon his build. He said the only issue he's had with his 4T80 was the first one chewed itself up due to a long 2-3 shift. He flipped the 2-3 piston on his subsequent transmission and hasn't had any issues since. Not sure if you have done that or not.
Also, Will, I did not realize that there were fine splines vs 'standard'(?) splines! How do you go about finding this information? (I want to make sure that the axles I'm going to be ordering don't just fit, but fit properly - sorry for the slight high-jack).
I have modified the 1-2 and 2-3 accumulators and increased the size of the feed holes in the spacer plate to firm up the shifts. Won’t know how it works until it runs. The 2-3 shift is notoriously lazy on the 4t80, so hopefully these changes will help keep the clutches alive.
100% of the 4T80's that came into my shop needing major repair were due to a badly slipping torque converter clutch. The lip separates on the metal clad turbine shaft seals in the channel plate. I would change them while trans is out. The Delco numbers are: 24201991 and 24201992.
Trans part suppliers such as Transtar, WIT, ect should have them. If you search by part number, they show up on Rock Auto also.
100% of the 4T80's that came into my shop needing major repair were due to a badly slipping torque converter clutch. The lip separates on the metal clad turbine shaft seals in the channel plate. I would change them while trans is out. The Delco numbers are: 24201991 and 24201992.
Trans part suppliers such as Transtar, WIT, ect should have them. If you search by part number, they show up on Rock Auto also.
Marc
Absolutely correct!
Changed both seals while I had it apart, as well as the common worn bushing that supports the driver side output shaft.
Over the last week or so, my son and I have been busy. I removed the remaining portion of the trunk that I no longer used, cleaned the cv joint grease from the 1000 axles I’ve broken lol. Added a 1x2 cross bar for support, masked and painted the engine bay.
Yesterday I replaced the old rubber -6AN fuel lines with PTFE lines so hopefully there will be less fuel smell.
Finally this evening, the 3800 and 4T80 were bolted to the subframe and installed in the car. Need to build a new rear manifold and hot side as the stock 3800 rear manifold interferes with the transmission, and it will be nearly ready to fire.
Anyone interested in a bolt on turbo setup? Will probably look to sell the ported rear manifold which has been modified for 4 bolts to the turbo adapter with wastegate output. Accepts a T3 turbo and 44/46mm wastegate. Can probably include a 3” or 4” down pipe as well.
------------------ 10.007 @ 135.54MPH. <-- Video Best 60' 1.42 Best mph 138.82 Billet 6262 Precision turbo, PT1001 intercooler, ST1 cam, 140lb springs, comp pushrods, HV3, stock L32 bottom end and heads.
Got the coil overs together tonight. This should allow for some bigger tires when this thing hits the road again. KYB struts, Allstar sleeves, Qa1 275lb high travel springs. 8.8lbs lighter per side vs stock, help counteract some of the extra weight the Transport spindles/brakes are adding.
[This message has been edited by LFiero67 (edited 03-07-2022).]
Son and I got the pre-turbo hot side built this weekend. Last few joints to be welded up and then the turbo can be mounted. Be a few weeks until the downpipe and wastegate are built, but some good progress the last couple days.
Manifold is flipped front PLOG, with rework to Center two mounting holes, outlet cut off. 2” crossover with v band flange, 2.5” at union into a T4 flange. Still running the 6262 for now, but room to grow.
------------------ 10.007 @ 135.54MPH. <-- Video Best 60' 1.42 Best mph 138.82 Billet 6262 Precision turbo, PT1001 intercooler, ST1 cam, 140lb springs, comp pushrods, HV3, stock L32 bottom end and heads.
Old M90 XP Cam time - 11.425 @115.60 1.543 60'
[This message has been edited by LFiero67 (edited 04-10-2022).]
Opened up the new gas tank from Rodney today. Looks like a nice piece, longer straps as my car is a 86, and new pads all included. Can’t wait I can get it in the car.
Didn’t post this when it happened, but the car runs and moves under its own power. Still lots of work to do, hopefully have it ready to drive next summer.
Since my last update I made the leap to Holley EFI. Today the car started for the first time with TerminatorX Max ecu. Few hiccups, but now it runs possibly smoother than with the stock PCM.
