Pontiac 455, Edelbrock rpm intake & hood clearance?

[84GP455]

I would definitely put the th200-4r in. I just went from a th400 to the th200-4r and man, what a difference! I also went from 2.41's to 3.42's so the th400 was screaming on the highway. I couldn't go to the beach! What a big improvement on take off's too, it's much quicker off the line. I got the th2004r from a 87' GN so I'm not worried about the transmission holding up with my 455, those GN's made some serious tourqe, so far so good, it was by far the best performance improvement that I have done to the car.

 

[G-Body_Vet]

I would definitely put the th200-4r in. I just went from a th400 to the th200-4r and man, what a difference! I also went from 2.41's to 3.42's so the th400 was screaming on the highway. I couldn't go to the beach! What a big improvement on take off's too, it's much quicker off the line. I got the th2004r from a 87' GN so I'm not worried about the transmission holding up with my 455, those GN's made some serious tourqe, so far so good, it was by far the best performance improvement that I have done to the car.

The one I picked up is a BQ trans from an '84 T-type. From what I've always read you need hardened parts and a billet forward drum to live behind any real torque???

 

[84GP455]

The one I have is a BRF code from a 87 GN which I think had those improvements, as long as your TV cable is adjusted correctly that is the most important thing, these transmission's are very sensitive to TV cable settings. You could burn up a brand new transmission with all the bullet proof parts you want in 10 minutes if that cable isn't adjusted properly. I've been beating on mine pretty well since 2012 😀

 

[buzz77]

Would you know if the jegs double bump 200 4r cross member will work with the gforce extention rail for our 78-80 cars? They have the best price at 129.99. Iceman of Malibu classics quoted me 169.00 and 35.00 plus shipping for his lightweight 200 4r double hump crossmember and extention rail adaptor.

 

[G-Body_Vet]

Would you know if the jegs double bump 200 4r cross member will work with the gforce extention rail for our 78-80 cars? They have the best price at 129.99. Iceman of Malibu classics quoted me 169.00 and 35.00 plus shipping for his lightweight 200 4r double hump crossmember and extention rail adaptor.

I'm 99% sure it will. All the extension does is replicate how post '83 frames came from the factory. I added the extension to my car since it's off the frame right now (makes drilling a little easier btw). I had a Jegs x-member in a different car and now I have a G-force. The Jegs fit nicely but isn't as robust as the G-force....which also fits well. I wanted the extra strength so I shelled out the extra cash.

 

[buzz77]

Is the power steering pump from the 301 a simple swap with a Pontiac 400 or will it require Pontiac 350/400/455 specific brackets? Also are all the sender units loated in the same spots? For example I have the gauges not the dummy lights will the oil and coolant sender be in the same locations?

 

[84GP455]

Yes the 301 power steering unit will bolt up and the sending unit locations are the same.

 

[buzz77]

The one I have is a BRF code from a 87 GN which I think had those improvements, as long as your TV cable is adjusted correctly that is the most important thing, these transmission's are very sensitive to TV cable settings. You could burn up a brand new transmission with all the bullet proof parts you want in 10 minutes if that cable isn't adjusted properly. I've been beating on mine pretty well since 2012 😀

Is this a stock Transmission? How much power is your 455 making? I've always found the so called stage 1 hi performance 200 4r rebuild with skepticism. If the GNX produced 276hp and 360 foot pounds of torque net, these transmissions should hold up to most stock muscle car era engines without the need to beef them up. Why dish out 1600 to monster transmissions or whomever to 'bullet proof" it to stage 1. Yet others say the torque of the late 60's early 70's engines would destroy an overdrive transmissions.

 

[G-Body_Vet]

Is this a stock Transmission? How much power is your 455 making? I've always found the so called stage 1 hi performance 200 4r rebuild with skepticism. If the GNX produced 276hp and 360 foot pounds of torque net, these transmissions should hold up to most stock muscle car era engines without the need to beef them up. Why dish out 1600 to monster transmissions or whomever to 'bullet proof" it to stage 1. Yet others say the torque of the late 60's early 70's engines would destroy an overdrive transmissions.

The 200-4R evolved from the THM-200 and we're designed for econo cars....light weight and reduced rotating mass for fuel efficiency. They would eventually get more improvements through the years but they were never very strong. I've had 2 Monte Carlo SS and the stock 305 killed both of those transmissions. IIRC, a stock, smog era Pontiac 400 w/2bbl carb would put out 380 ft/lbs of torque. The 455's, 472 and 500 were all over 425+ ft/lbs.

I've ran lot of used stuff through the years and I'd rather go with something purpose-built or refurbished whenever I can. I've never owned a turbo Buick, so I can't speak on how well they hold up in stock form. I do know that the older I get, the less I want to drop a trans if I can help it. :lol:

It's one of those things I feel is justified spending money on I suppose. As much as I just want to use the one I have, I'll probably have it built to avoid a future headache.

 

[79GP6.6L]

The one I have is a BRF code from a 87 GN which I think had those improvements, as long as your TV cable is adjusted correctly that is the most important thing, these transmission's are very sensitive to TV cable settings. You could burn up a brand new transmission with all the bullet proof parts you want in 10 minutes if that cable isn't adjusted properly. I've been beating on mine pretty well since 2012 😀

Is this a stock Transmission? How much power is your 455 making? I've always found the so called stage 1 hi performance 200 4r rebuild with skepticism. If the GNX produced 276hp and 360 foot pounds of torque net, these transmissions should hold up to most stock muscle car era engines without the need to beef them up. Why dish out 1600 to monster transmissions or whomever to 'bullet proof" it to stage 1. Yet others say the torque of the late 60's early 70's engines would destroy an overdrive transmissions.

Keep in mind that there is a big difference in the onset of torque between a 3.8 turbo and a 455. One produces a gradual buildup, the other a sudden shockwave. Personally I think the 4L80E (with an adapter plate) with its higher torque rating is a much better choice for a Pontiac engine.