th425 550hp /600 tq

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kanotixxx
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Years Owned: 1966
Location: France

th425 550hp /600 tq

Postby kanotixxx » Sun Nov 30, 2014 3:48 am

Hello , i'm looking for a new th425 transmission for my 66' toronado who can handle around 550hp/600 tq.

I have found the manny trovao shop on internet,he was ok to do it but i can't contact him anymore since some months by email and my english spoken isn't accurate.
Is anyone know him or knows a good transmission shop ?
I'm in oversea so i'm looking for a good quality part for this project.

I had an account here but i can't retrieve it.

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xgecko
Posts: 455
Joined: Wed Oct 13, 2010 9:21 pm
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Years Owned: My first Toronado was a 1968 W-34 with the bucket seats and center console... (weeps gently) It was a New England rustbucket in 1982 after less than 14 years. So sad. But it is what infected me and before I knew it I had another '68, a '69, a '70 and eventually inherited a friend's '67 and another friends '73. After buying my brand new Grand Prix in 1988 I retired the last of my Toronados and pulled the 455 I had rebuilt along the way and put it into storage in a friend's barn where it is to this day.
In Mid September of 2010 I happened to see a repeat of the show where Jay Leno did his 66 Toronado and had an instant remission of the disease which resulted in my purchase of a 1969 in very good condition. I am now in the process of fully rehabilitating it and hope to have it on the road in the spring of 2011.
Location: Gig Harbor, WA

Re: th425 550hp /600 tq

Postby xgecko » Fri Jan 16, 2015 2:26 pm

I used Manny and had an excellent experience in all. I highly recommend him.

As for contacting him you will have to keep trying.

Regarding your power/torque figures I have to say I am interested in how you area accomplishing this.

I have EFI, the Rockwell intake, the Mondello RH-94-95 Roller cam in my car. I have no idea yet how much it puts out, but I have no fear that the trans will take it as long as the shifts are not too hard - hard shifts really kill that link belt over time. It is the only abuse it does not like (assuming adequate lubrication, of course).

Where do you get your power figures from, and what cam and intake are you using to get these figures?
I have my Fuel Injected Toronado. Life is good! 8-)
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Schurkey
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Re: th425 550hp /600 tq

Postby Schurkey » Fri Jan 16, 2015 11:38 pm

The transmission internals of the TH425 are exceedingly similar to the internals of the rear-drive TH400. A 400 can be built to take an insane amount of power.

That leaves the chain drive on the input side, and the differential on the output side, as potential trouble-spots. I'm told the '68-newer differential is stronger than the '66--'67.

A high-stall converter will ease the shock loads on the chain drive, as will NOT using a harsh shift-kit. I'm not sure how much power a switch-pitch torque converter system will take--I suspect you're at or beyond the capacity of those small stator splines.

kanotixxx
Posts: 3
Joined: Sun Nov 30, 2014 3:41 am
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Years Owned: 1966
Location: France

Re: th425 550hp /600 tq

Postby kanotixxx » Wed Jan 27, 2016 6:02 am

thanks you for your answers,i forget to update this topic.I finally contact manny and he built me a strong th425.
Here's the informations about the trans :

Overhaul kit with Alto Red frictions
Apply piston housings
34 Element Sprag for intermediate clutch
Low roller clutch
Heavy duty front band
Detent Solenoid
Stator solenoid
Governor tube filters, speedo bushing, viton o-rings
Center support machining
Governor gear
Speedometer gear
Stator tube
Thrust washer kit
Stainless hardware kit
Steel plates and waves kit
Bearing kit
Bushing kit
Oil ring kit
Valve body spring kit
3/8 fittings and vent elbow kit
Sprocket bearings
Center support bronze bushings
Billet forward hub with Torrington bearing
H/D S/P torque converter with six lugs


And about the engine, it makes 488hp/574tq on dyno with this ,it's running on E85
452ci
Racetec pistons, 4032 material, 4.155 bore, 1.5, 1.5, 3.0 ring pack
Scat BBC 6.800 H beam rods
12.0:1 compression
Edelbrock Performer with the center divider cut 1/2" from the bottom.
Quick Fuel E85 750cfm carb (it's really about 780cfm)
MSD pro billet distributor
Edelbrock heads, 2.125 intake, 1.68 exhaust /porting on the intake side.
HV pump
Toro pan
ARP Studs and straps
Lunati Hyd roller;
234/238@.050
.555/.565 lift with 1.6 rockers
Full roller rockers
Restricted 3/8 one piece pushrods

User avatar
xgecko
Posts: 455
Joined: Wed Oct 13, 2010 9:21 pm
TOA Membership Number: 831
Years Owned: My first Toronado was a 1968 W-34 with the bucket seats and center console... (weeps gently) It was a New England rustbucket in 1982 after less than 14 years. So sad. But it is what infected me and before I knew it I had another '68, a '69, a '70 and eventually inherited a friend's '67 and another friends '73. After buying my brand new Grand Prix in 1988 I retired the last of my Toronados and pulled the 455 I had rebuilt along the way and put it into storage in a friend's barn where it is to this day.
In Mid September of 2010 I happened to see a repeat of the show where Jay Leno did his 66 Toronado and had an instant remission of the disease which resulted in my purchase of a 1969 in very good condition. I am now in the process of fully rehabilitating it and hope to have it on the road in the spring of 2011.
Location: Gig Harbor, WA

Re: th425 550hp /600 tq

Postby xgecko » Wed Jan 27, 2016 6:44 am

Interesting. I assume you had to cut a hole in the hood to allow clearance for the intake? Any pics? What are the Power and Torque Peak RPM values? Did you install Headers?

My cam is not quite as aggressive as yours, but it is close. I do not have the intake or exhaust to allow it to breath properly so I am no doubt limited by that as well. Not to mention I am not running E85 so my 10:1 compression is resulting in detonation at timing advances above roughly 30 degrees. This is robbing me of much power, and my intent is to install Water/Methanol injection this spring to address this and finally see what it is like with full power.

Given what you spent on the motor I am surprised you did not go EFI. It is far superior in my opinion to a carb as you can easily adjust it, no cold start issues, and I can set the timing from inside the car - you already seem to have the distributor you need to go with the MSD Atomic EFI, so what is another $2k - $3K when you are this deep anyway? Give it some thought, you will not regret it if you do it.
I have my Fuel Injected Toronado. Life is good! 8-)
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kanotixxx
Posts: 3
Joined: Sun Nov 30, 2014 3:41 am
TOA Membership Number: 0
Years Owned: 1966
Location: France

Re: th425 550hp /600 tq

Postby kanotixxx » Thu Jan 28, 2016 12:29 am

yes xgecko i had a scoop when i import the toronado so i got the extra clearance for this intake.I tried to find headers but there is no one who is working, i'll do custom headers in future,the stock exhaust manifolds are killing this engine performance.
We got a lot of e85 in France so i use it , i did a complete strong fuel system with ptfe hose/qf30-230.
About the EFI i choose to stay on carb , i don't want to modernize too much this old lady, it's not really about price.
I bought an accusump too ,i'll post pic's in end of february when i come back to home.

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Eightballz
Posts: 125
Joined: Mon Sep 27, 2010 2:15 pm
TOA Membership Number: 826
Years Owned: 1970 Olds Toronado GT

Re: th425 550hp /600 tq

Postby Eightballz » Thu Jan 28, 2016 4:51 am

really cool thread...can you be more specific on the transmission build?

i also built a performance toro engine just like yours but with stock intake and still stock exhaust manifolds so far...gonna build custom headers soon. buddy from the US built his own headers for a 1971 (have some pics but they are too large to attach)

applied GMC sells the headers he started with

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Eightballz
Posts: 125
Joined: Mon Sep 27, 2010 2:15 pm
TOA Membership Number: 826
Years Owned: 1970 Olds Toronado GT

Re: th425 550hp /600 tq

Postby Eightballz » Thu Jan 28, 2016 5:52 am

here are some pics
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1251_p14788.jpg (79.14 KiB) Viewed 15112 times

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Eightballz
Posts: 125
Joined: Mon Sep 27, 2010 2:15 pm
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Years Owned: 1970 Olds Toronado GT

Re: th425 550hp /600 tq

Postby Eightballz » Thu Jan 28, 2016 5:52 am

more
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photo s1.JPG
photo s1.JPG (203.05 KiB) Viewed 15110 times
photo 2.JPG
photo 2.JPG (199.05 KiB) Viewed 15110 times
photo 1.JPG
photo 1.JPG (188.36 KiB) Viewed 15110 times

User avatar
Eightballz
Posts: 125
Joined: Mon Sep 27, 2010 2:15 pm
TOA Membership Number: 826
Years Owned: 1970 Olds Toronado GT

Re: th425 550hp /600 tq

Postby Eightballz » Thu Jan 28, 2016 5:53 am

and more
Attachments
photsdfo 2.JPG
photsdfo 2.JPG (88.13 KiB) Viewed 15108 times
photoa 3.JPG
photoa 3.JPG (377.03 KiB) Viewed 15108 times
photo.JPG
photo.JPG (298.46 KiB) Viewed 15108 times


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