How many hp without girdle ?

[Amelio]

I think I got lost somewhere....we started out talking about a girdle now we are on a mid-plate

 

[KL Mallender]

I take it you are an engineer in need of a fabricator

No thanks, I am no longer involved with Buick performance parts, just offering what I know to those here still trying to play nice with the old 3.8 turbo.
There are quite a few fabricators in the Buick community that are capable of producing a quality piece though, especially if they combined it with an adapter for the 3800 engine family for use with RWD transmissions. It(mid-plate) would solve most if not all block/bearing trouble that manifests itself between mains 2 & 3.
Good luck,

Kevin.

 

[KL Mallender]

I think I got lost somewhere....we started out talking about a girdle now we are on a mid-plate

Your not lost, a "girdle" ties the main caps and block rails together for ultimate strength of the block, a "mid-plate" harness's the twisting of the block under load from front to rear.
Using only factory mounts/tie down straps at the front exposes the block to mind numbing amounts of twist through the bellhousing, how much you ask??
Ask anyone who has tested the actual amount of torque necessary to break a low/roller clutch or rip the lugs out of the trans case.
Good luck,

Kevin.

 

[RIFF RAFF]

Kevin do you have time to build a motor for me ? 231 that is ..

 

[KL Mallender]

Sorry brother, the only engines I'm playing with today are from the antichrist in the blue oval(4.6).
There are plenty here that are vastly more up-to-date in Buick V6 knowhow than I am, my ideas of a performance V6 conflict horribly with lock-up converters and low rpm "chuggle" when mass air sensors are used, non-lockup and speed density systems ONLY.
Good luck,

Kevin.

ps; any update on those responsible for the break-in at your shop?

 

[kidglok]

I guess then the question is, theoretically whats stronger:

1. caps no girdle
2. caps and girdle
3. girdle no caps

 

[bison]

Real world examples

This one had a couple years of beatings on it and the slowest pass it ever made was 10.88 about 4 days after i got it together. 150k miles stock as assembled from GM. The #2 main was eventually found to be cracked:
http://www.turbobuick.com/forums/en...ked-piston-high-mileage-stock-bottom-end.html


This one was an experiment and got hot on #1 a couple times. Stock as assembled from GM bottom end also. I havent taken it apart yet:
http://www.turbobuick.com/forums/turbo-lounge/354926-so-what-will-happen-bisons-car-tomorrow.html

Pistons failed before anything else. 700+hp

 

[Amelio]

Your not lost, a "girdle" ties the main caps and block rails together for ultimate strength of the block, a "mid-plate" harness's the twisting of the block under load from front to rear.
Using only factory mounts/tie down straps at the front exposes the block to mind numbing amounts of twist through the bellhousing, how much you ask??
Ask anyone who has tested the actual amount of torque necessary to break a low/roller clutch or rip the lugs out of the trans case.
Good luck,

Kevin.

I understand the differences between the two.....it seems that we started talking about girdles then jumped to mid-plates.....So back to your comment abouve if I understand it correctly,you are saying that a front tie down is not a good idea due to the front being staionary and allowing the rear of the block to twist?

I assume this is also the same for a front engine plate which I see on many race cars (I have never seen one on a TB mostly older muscle cars) I was contemplating putting a front engine plate on my '69 Vette, I am having shifter linkage issues when the car is twisting around 7-7500prm...it does not have a problem at 6500rpm but the shifter usually locks up when I go to third at higher rpm due to engine twist. I used to have a tie down on my buick but it has been removed due to damage from a fire. Also are you reccomending one for a street car and I guess thats a loaded question also since there are 1000hp street cars out there. I dont know that my GN makes enough hp and tq to warrant such a mod......what are your thoughts?

Thanks for the input.....

 

[KL Mallender]

Modern "Street Cars" can run the spectrum from docile to insane, producing power is somewhat easy compared learning how to successfully harness it.
Considering the torque output potential of any forced induction engine, I would consider a "mid-plate" a top priority for durability/longevity.
It(mid-plate) should hold the mass weight of the engine and transmission, with flexible mountings at the front of engine and rear of transmission to allow for movement in the chassis.
The factory engine mounting locations were designed for ease of fitment and vibration control as priority, not for trying to restrain the reaction forces of 600+ ft lbs of shaft torque.
If I were to build a 3.8 today, I would most certainly use a block girdle(steel caps would be unecessary IMHO) to make the best of a weak situation considering what is likely to be asked out of it under load, and install a mid-plate to handle the restraint issue.
Best of luck guy's,

Kevin.

 

[EVIL]

Sorry to keep this off track but i have a question.

It has been stated that a front engine strap is not good.
What if you use the front engine strap with a rear RJC motor brace?

thank you
D

 

[Amelio]

Modern "Street Cars" can run the spectrum from docile to insane, producing power is somewhat easy compared learning how to successfully harness it.
Considering the torque output potential of any forced induction engine, I would consider a "mid-plate" a top priority for durability/longevity.
It(mid-plate) should hold the mass weight of the engine and transmission, with flexible mountings at the front of engine and rear of transmission to allow for movement in the chassis.
The factory engine mounting locations were designed for ease of fitment and vibration control as priority, not for trying to restrain the reaction forces of 600+ ft lbs of shaft torque.
If I were to build a 3.8 today, I would most certainly use a block girdle(steel caps would be unecessary IMHO) to make the best of a weak situation considering what is likely to be asked out of it under load, and install a mid-plate to handle the restraint issue.
Best of luck guy's,

Kevin.

ok I am getting the picture and it does sound like a great mod to compliment a girdled engine and keep everything from twisting but I am just not sure where to draw the line on when needed. You mention 600 + ft lbs......well I dont think I am there...maybe if I were to run 30 psi I may be close to that but I usually run around 18 which keeps me about 100 ft lbs away from 600.

With that being said if I did decide to go that route...(using a mid plate) do they make them for specific cars or is it a complete fabrication from the get go? Also how thick of a plate are we talking,I assume no too thick or you run into issues with bolting the converter in and the input shaft not being deep enough in the converter correct?