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Shakercars's 1972 Trans Am

2019 August
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Kurk_Kurk

My '78 Firebird Esprit

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On 5/29/2019 at 9:23 AM, Last Indian said:

Curtis, just in case you’re unaware, you can buy oversized piston rings in incremental sizes, .003, .005 etc., but you’re going to have to dismantle the engine to hone it. In the end a bare block hauled to a shop and new pistons and rings may be the better choice. Honing can be tricky when it comes to true roundness and a straight bore! More often than not anything more than glaze busting will leave a block out of round and tapered.

 

On 5/29/2019 at 10:55 AM, Frosty said:

Agreed. This is not the news you wanted to hear and it is a set back for sure. However, look at this as an opportunity to prepare and blueprint the bottom end correctly. You don't have to break the bank if you are building a strong street motor. Yes it will cost you more money and time than you currently planned for. However, once it's done you will say to yourself (and your friends) it was worth every penny.

Fix it right now and you will have a strong, enjoyable motor for years to come.

 

Yup, i know about the oversized rings. im just worried about boring it over again. I'm already 30 over bore, so what would be next? 40 over? i know i cant go past 60 over, but i feel im cutting it close now. I'd love to see if i can get away with honing because of this. But if i absolutely HAVE to, ill take it to a shop. Thakfully my dad knows a guy that can get the work done really well for a case of beers and $300 

And frosty, you're damned right im gonna build this the right way without any Spectre oil pans or gaskets lol. I'll stomach the extra few bucks and buy some legitimate parts this time around. Im glad im choosing street though, can't imagine how much money i'd be down with a race engine build!

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28 minutes ago, Kurk_Kurk said:

And frosty, you're damned right im gonna build this the right way without any Spectre oil pans or gaskets lol. I'll stomach the extra few bucks and buy some legitimate parts this time around. Im glad im choosing street though, can't imagine how much money i'd be down with a race engine build!

In 2004, Lucy's original 455 gave up the ghost, and the #8 connecting split into 3 pieces. The resulting damage blow two holes in my stock oil pan, one on each side - driver and passenger side. So during the rebuild, my engine builder spec'd a Melling stock Pontiac replacement pan. I've been very happy with it, no issues or oil leaks with it. I have a rope seal, which does leak from time to time, but that is not the oil pan's fault.

How much does a race engines costs? How much are you worth? LOL!

Another thing you could consider but it costs more money yet would be to have the machine shop sleeve the motor and that would allow you to bring it back into stock bore diameter. Still that gets expensive when you are talking all eight cylinders. If this was a SD or RA motor, or a numbers matching motor on a very rare or valuable Pontiac, it's probably worth it. Again, how deep is your wallet? Still it is an idea to consider. If it's my money, I'd consider the boring to .040 to .060 first, assuming you can't get away with just the honing.

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1 hour ago, Kurk_Kurk said:

 

 

Yup, i know about the oversized rings. im just worried about boring it over again. I'm already 30 over bore, so what would be next? 40 over? i know i cant go past 60 over, but i feel im cutting it close now. I'd love to see if i can get away with honing because of this. But if i absolutely HAVE to, ill take it to a shop. Thakfully my dad knows a guy that can get the work done really well for a case of beers and $300 

And frosty, you're damned right im gonna build this the right way without any Spectre oil pans or gaskets lol. I'll stomach the extra few bucks and buy some legitimate parts this time around. Im glad im choosing street though, can't imagine how much money i'd be down with a race engine build!

Food for thought!

Here’s the problem with honing. A typical drill operated hone only follows what’s there, I.E. taper, out of round etc. than it amplifies it. You might get lucky, but if not than you’ll have to bore bigger than you might if you started with a block honing machine. If you start with a block honing machine first you may be able to hold the new bore to .010. Giving you just the .040 over. 

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On 5/31/2019 at 10:36 AM, Frosty said:

Another thing you could consider but it costs more money yet would be to have the machine shop sleeve the motor and that would allow you to bring it back into stock bore diameter. Still that gets expensive when you are talking all eight cylinders. If this was a SD or RA motor, or a numbers matching motor on a very rare or valuable Pontiac, it's probably worth it. Again, how deep is your wallet? Still it is an idea to consider. If it's my money, I'd consider the boring to .040 to .060 first, assuming you can't get away with just the honing.

The numbers matching motor is long gone by now. It was your basic 305CI enigne and i didn't see much value in that at the time. Boring the engine is probably not the best in my case, considering i'd need all new pistons for the new bore, and my pockets are running shallow. Would it be wise to bore it out to .060 and then sleeve it to .030?

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Are you going sleeve one cylinder or all eight?

The machine shop will significantly over bore each cylinder in the block to insert the new steel sleeves and then they bore it to stock or whatever over bore is needed. So in theory, they can take it back to .030 over.

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On 6/10/2019 at 10:49 AM, Frosty said:

Are you going sleeve one cylinder or all eight?

The machine shop will significantly over bore each cylinder in the block to insert the new steel sleeves and then they bore it to stock or whatever over bore is needed. So in theory, they can take it back to .030 over.

I'd feel a lot more comfortable sleeving all eight. might as well keep it all evenly machined all around to avoid any more mishaps. 

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43 minutes ago, Kurk_Kurk said:

I'd feel a lot more comfortable sleeving all eight. might as well keep it all evenly machined all around to avoid any more mishaps. 

Make sure you talk to your machine shop. Have them explain to you exactly what steps they go thru to prepare the block for the new sleeves. Review their equipment. Any competent shop will give you a tour.

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Posted (edited)

No photos this time, unfortunately but i took my entire engine apart and took a good look at the bearings. Apparently i was leaking oil out of the oil pan faster than i could keep up so i need new bearings, which is no big deal. I already have an aluminum oil pan, black and silver finned ready to install. HOWEVER i need some mucho geniuses here.

I have the 2 bolt main Block. Not very strong, safe zone is up to 500hp and i understand this. The current engine components already make up to 420hp with a stock specification crank shaft. I've recently found that there is a Main Girdle i can use which essentially makes the block a 10 bolt main by connecting all bearings, increasing its strength and reliability to pump out more than 500hp. Great right? Now, since that's an option, would it be okay to throw in a stroker crank and make this into a 383 stroker? or would doing this be too risky?

Edited by Kurk_Kurk

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20 hours ago, Kurk_Kurk said:

No photos this time, unfortunately but i took my entire engine apart and took a good look at the bearings. Apparently i was leaking oil out of the oil pan faster than i could keep up so i need new bearings, which is no big deal. I already have an aluminum oil pan, black and silver finned ready to install. HOWEVER i need some mucho geniuses here.

I have the 2 bolt main Block. Not very strong, safe zone is up to 500hp and i understand this. The current engine components already make up to 420hp with a stock specification crank shaft. I've recently found that there is a Main Girdle i can use which essentially makes the block a 10 bolt main by connecting all bearings, increasing its strength and reliability to pump out more than 500hp. Great right? Now, since that's an option, would it be okay to throw in a stroker crank and make this into a 383 stroker? or would doing this be too risky?

Well actually a 2 bolt main can handle 600 hp & 7000 rpm, but there is a lot that goes with that statement! If you’re talking racing? Than no! If you’re talking street once in a while then yes. Main cap flex in a 2 bolt starts at just under 600 hp and about 6000 rpm. The advantage of this type of build is more low end power, if done right. The disadvantage is if you get over zealous & fuel economy. 

So in general I would skip the girding and just do a good build. 

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20 hours ago, Kurk_Kurk said:

No photos this time, unfortunately but i took my entire engine apart and took a good look at the bearings. Apparently i was leaking oil out of the oil pan faster than i could keep up so i need new bearings, which is no big deal. I already have an aluminum oil pan, black and silver finned ready to install. HOWEVER i need some mucho geniuses here.

I have the 2 bolt main Block. Not very strong, safe zone is up to 500hp and i understand this. The current engine components already make up to 420hp with a stock specification crank shaft. I've recently found that there is a Main Girdle i can use which essentially makes the block a 10 bolt main by connecting all bearings, increasing its strength and reliability to pump out more than 500hp. Great right? Now, since that's an option, would it be okay to throw in a stroker crank and make this into a 383 stroker? or would doing this be too risky?

 

3 minutes ago, Last Indian said:

Well actually a 2 bolt main can handle 600 hp & 7000 rpm, but there is a lot that goes with that statement! If you’re talking racing? Than no! If you’re talking street once in a while then yes. Main cap flex in a 2 bolt starts at just under 600 hp and about 6000 rpm. The advantage of this type of build is more low end power, if done right. The disadvantage is if you get over zealous & fuel economy. 

So in general I would skip the girding and just do a good build. 

I agree with Last Indian. You have to have a goal in mind with you motor. Most of us don't have limitless budgets. So what is your vision for the motor and the car?

If you say street performance, handling, occasional autocross or the quarter mile blast, then 400-500 HP should be fine. Also, if you start pushing much more horsepower then that you have to spend more money in other parts of the car too, such as bigger brakes, sub-frame connectors/roll cage, etc. You get the point, going faster means more money needs to be spent elsewhere too. Personally, I am happy to put the rice rockets in their place. I don't need to beat the latest Corvette or Hell-kitten.

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As a side bar, a couple of things you can do to improve 2 bolt main performance is this. Replace the bolts with studs! The proper studs will be stronger & the corresponding nuts will be stronger. Also use permatex aviation form a gasket on the stud threads on insertion of the stud. It is at this time you should torque the studs independent of the caps. Then when you install the caps over the studs apply this same permatex to the top threads, install the nut and torque the cap.

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3 hours ago, Frosty said:

 

I agree with Last Indian. You have to have a goal in mind with you motor. Most of us don't have limitless budgets. So what is your vision for the motor and the car?

If you say street performance, handling, occasional autocross or the quarter mile blast, then 400-500 HP should be fine. Also, if you start pushing much more horsepower then that you have to spend more money in other parts of the car too, such as bigger brakes, sub-frame connectors/roll cage, etc. You get the point, going faster means more money needs to be spent elsewhere too. Personally, I am happy to put the rice rockets in their place. I don't need to beat the latest Corvette or Hell-kitten.

Hitting those Rice rockets is my pastime but i want to make sure i can embarrass them with a Naturally Aspirated Motor. So in a sense, i will be racing with the engine. not every day, but i will be frequent enough to the point where i want to be able to drive the car home from the track every race. And i've already gotten the new Posi rear, 3.75 gear, rear disc brake conversion, suspension and all the other goodies. It's just a matter of getting the parts on since she's undergoing some SERIOUS metal work on the floors and rails. 

1 hour ago, Last Indian said:

As a side bar, a couple of things you can do to improve 2 bolt main performance is this. Replace the bolts with studs! The proper studs will be stronger & the corresponding nuts will be stronger. Also use permatex aviation form a gasket on the stud threads on insertion of the stud. It is at this time you should torque the studs independent of the caps. Then when you install the caps over the studs apply this same permatex to the top threads, install the nut and torque the cap.

Super friggen useful to know. might be why the Girdle comes with studs and nuts too. But i think i'll be taking the Girdle route as it's more Peace Of Mind.

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1 hour ago, Kurk_Kurk said:

Hitting those Rice rockets is my pastime but i want to make sure i can embarrass them with a Naturally Aspirated Motor. So in a sense, i will be racing with the engine. not every day, but i will be frequent enough to the point where i want to be able to drive the car home from the track every race. And i've already gotten the new Posi rear, 3.75 gear, rear disc brake conversion, suspension and all the other goodies. It's just a matter of getting the parts on since she's undergoing some SERIOUS metal work on the floors and rails. 

Super friggen useful to know. might be why the Girdle comes with studs and nuts too. But i think i'll be taking the Girdle route as it's more Peace Of Mind.

Nothing wrong with that!!

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23 hours ago, Kurk_Kurk said:

Hitting those Rice rockets is my pastime but i want to make sure i can embarrass them with a Naturally Aspirated Motor. So in a sense, i will be racing with the engine. not every day, but i will be frequent enough to the point where i want to be able to drive the car home from the track every race. And i've already gotten the new Posi rear, 3.75 gear, rear disc brake conversion, suspension and all the other goodies. It's just a matter of getting the parts on since she's undergoing some SERIOUS metal work on the floors and rails. 

Super friggen useful to know. might be why the Girdle comes with studs and nuts too. But i think i'll be taking the Girdle route as it's more Peace Of Mind.

I love your goal too. I love putting rice rockets back in the bowl.  Since this is primarily a street car and part time race car, you have to be able to live with it on the street.

Indyman Joe's car is a good example. He has a stout 400 under the hood of his '72 Luxury Lemans. It's strong. He does the occasional 1/4 mile just to beat his buddy's big dollar Camaro. However, Joe's car is still a street car that he can take cruising or on long weekend and Sunday drives with his wife. It has no roll cage, stock interior, no line lock, but it does have a Ford 9" rear end and 4-wheel disc brakes (now). Someday he may actually paint it (sorry Joe - you know I had to kid you about it!). 

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3 hours ago, Frosty said:

I love your goal too. I love putting rice rockets back in the bowl.  Since this is primarily a street car and part time race car, you have to be able to live with it on the street.

Indyman Joe's car is a good example. He has a stout 400 under the hood of his '72 Luxury Lemans. It's strong. He does the occasional 1/4 mile just to beat his buddy's big dollar Camaro. However, Joe's car is still a street car that he can take cruising or on long weekend and Sunday drives with his wife. It has no roll cage, stock interior, no line lock, but it does have a Ford 9" rear end and 4-wheel disc brakes (now). Someday he may actually paint it (sorry Joe - you know I had to kid you about it!). 

True, true! My “69” Z was that car! As a new car it was a great all around car! Quick, fast and semi comfortable for a sports car. Yet over the 35 years of ownership I did end up going to far from a comfort perspective, or at least so my wife said. 😞 

A 600hp mid 10 second car that pulled 1 & a quarter Gs on a 300 ft skid pad wasn’t that great for the street except for short durations. 3800 rpm @ 55mph 6 mpg. A fairly stock exhaust that you could hear coming due to the rumble 2 blocks away. All  were part of the reason I sold it after 35 years of ownership!

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Definitely going to stay away from a roll cage for the time being. I like the comforts of the car and wouldn't want them interfered. Plus, having an interior for comfort allows the inquisition of a passenger to scare shitless. Because that's always a plus.

ANYWHO we struck gold! $650 bucks later...

This car was sitting in a local landscaper's yard for 25 years as payment for a project that totalled 800 bucks. The roof is rotted and the original owner is long gone as well as the title. It's a true 1978 trans am and those fenders, doors and rear end will be perfect for 'Angry Bird.'

Well, now that the car is going to be multi colored, might as well call it 'Angry Parrot'

20190824_152224.jpg

20190824_153911.jpg

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Way cool. Thanks for sharing. Thanks for the update on your ride.

So why not take the open diff and turn it into a posi unit with the gear ratio you want? Once you are done stripping the Trans Am for the parts that you want to keep, you should be able to sell it/scrap it for money for the rear end.

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19 hours ago, Frosty said:

So why not take the open diff and turn it into a posi unit with the gear ratio you want? Once you are done stripping the Trans Am for the parts that you want to keep, you should be able to sell it/scrap it for money for the rear end.

Because the blue car already has the open diff lol. So i'll be changing that diff to a posi. Thing is, i was really hoping to get the factory posi rear so a lot of the guess work would be eliminated. Now, i have to find a posi online or in a store and i'm not sure what i'm looking for. I'm finding posi rears with a collection of four springs. Others have an S clip in there. Realistically, the springs are better right? I'm also seeing tons of brands with barely any reviews, so how will i know which posi is good? Being indecisive is a huge crutch when it comes to this junk. 

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If you go to the online stores, my recommendation would be to buy from one of the following posi vendors: Eaton, Richmond, Yukon or Auburn.  Eaton, Richmond, and Auburn have been around for a very long time and are very reputable. Yukon got started in the 4x4 scene and have made a reputable name for themselves.

Final gear ratio is up to you - just remember that the numerically lower the number, the higher the gear. So a 2.08 gear is high and a 4.11 is low. A low gear is good for acceleration out of the hole but you suffer at the top of the rpm range. A high gear is good for freeway mileage. So a good compromise is around 3.55.

I am not following you regarding the suspension. Are you asking about leaf springs vs coil springs?

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suspension? no i was talking about the contraption inside the posi differential thing. Some are a spring, others are an S slip looking thing. (The whole rear end is Pure FORDing Magic to me) I was already looking at an auburn so good to know i was on the right track! Good thing i'm chucking my 3.73 gear to my dad's trans am, i won't need that especially since i'll be doing highway pulls. A 3.55 seems right up my alley. 

But then it hit me, the rear in my 2002 firebird is a Torsion Lock Diff with two worm gears that lock under a certain load of torque (?) (It's the Performance Y87 code, kinda like a V6 firebird GT) Is that rear, whatever it's officially called, able to fit into the 1978 rear end? 

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