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1980 Trans Am 4.9L engine upgrade

  
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1980 Trans Am 4.9L engine upgrade

 
groder67 groder67
New User | Posts: 3 | Joined: 05/11
Posted: 05/29/11
06:27 AM

I just bought a 1980 Trans Am with a factory 4.9L engine.  Is there anything I can do to this engine to get decent Horsepower out of it or am I wasting my time and money?

If it is worth spending money on can someone give me some upgrade combo ideas?

I do have a good running Chevy 350 I could use but would want to do the same with that.  I would definitely want to get more than factory HP out of the 350 so would like some combo suggestions on that also.

I just want to build a weekend cruiser that will keep up with the Chevelle's and GTO's.  I don't necessarily need to beat them just want to be rouhly on the same level.

Time to start the build, I can't sleep at night because I am contanttly thinking about the TA.  I guess I got the fever!  

barneyformula barneyformula
Addict | Posts: 3306 | Joined: 01/07
Posted: 05/29/11
07:16 AM

Ok, I'm going to start by stating that this is just mt opinion, nothing more. That being said, here are a few points to ponder:

1-swapping in a 350 Chevy is a step backwards, it involves butchering wiring and fuel lines, swapping battery to the opposite side, changing motor mounts and leaves the car with the pedigree of a mutt. I bought a 79 Formula that was originally 301 powered and the previous owner thought he had done a wonderful thing by swapping in a smogger 454 Chevy. By the time I fixed all of the butchery and got a running 350 Pontiac in there, needless to say I didn't share his opinion!

2-the 301 engine is fine for a cruiser, you will be hard pressed to get any serious power out of it. There is an engine builder on here by the name of Pontiacman8 who has some experience with 301's, I'm sure he will chime in with his opinions and advice. There is also a whole website and forum devoted to 301 followers. Go to to www.301garage.com and click on "301 engine discussion" for the forum.

3-last and most important is the fact that the easiest way to make a 301 powered Trans Am faster and quicker is to bolt in a 350/400/455 Pontiac. The mounts are the same if you use a block from the 70's and if you get an older block, there are adapter plates to use the newer brackets. Wiring/plumbing/hoses etc are almost bolt-in stuff. That's the easy way to keep up with the pack!

I hope this helps.
Steve  
A little help... 'cause we don't all have to learn the hard way!

69GTOby 69GTOby
Guru | Posts: 1114 | Joined: 02/09
Posted: 05/29/11
07:48 AM

+1 Steve.  The 301 will never keep up with the bigger brothers.  But, if it is original, I would rebuild the 301 with a mild cam and exhaust, fine tuned ignition and carb.  If not original to the car, a 350 Pontiac like Steve's Formula (above) would be a great idea.  I would never put a Chevy or any other brand engine in there out of principle and bc of all the required changes.  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

Torqued400 Torqued400
Addict | Posts: 2479 | Joined: 10/08
Posted: 05/29/11
08:35 AM

+2 If you have a boat the 301 makes a fine anchor. Grin  
"We build Excitement"

69GTOby 69GTOby
Guru | Posts: 1114 | Joined: 02/09
Posted: 05/29/11
08:59 AM

Hey, hey, I didn't say that, T!   Tongue  Actually, it ain't all that bad.  It's got its advantages.  It is lighter weight...  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

Torqued400 Torqued400
Addict | Posts: 2479 | Joined: 10/08
Posted: 05/29/11
10:09 AM

Grin  I'm sorry, its just because I had one in a really nice Firebird that I bought when my wife and I got married. I have to admit it normaly got her where she was going and she had to have the air cond going all the time so I can say that much for it but I can't count the times I would have to work on or go pick it up off the side of the road, mostly overheating or no oil in it. My wife is like a lot of women, she turns the key on and thats about it and its suppose to go, flat tire, forget about it, low oil, whats that, overheating...well you know. Anyway I wanted to put a 400 in it but she wouldn't have it, she got it in her mind that she was getting a new car and just didn't want that one anymore, so I had to get rid of a nice looking Firebird and we bought her a new Blazer and thats another story that would fill up this page. Tongue As far as one that runs good and doesn't leak oil, I'm happy for you, but I think you'd be much happier with a 350,400 or 455. IMHO. sorry the long sad story. -T  
"We build Excitement"

Brazil Brazil
Addict | Posts: 3945 | Joined: 06/09
Posted: 05/30/11
04:42 AM

Gotta go with the guys on this one. I did that exact swap of putting a Chevy 350 in a 301 Trans Am. It was an 81 Turbo and the computer was driving me crazy, plus I couldn't work on it like a normal engine.

The only thing I really had to change were the motor mounts, and transmission. I left the battery where it was with longer cables, and the wiring wasn't too much of an issue. But after installing an Edelbrock Performer, carb, and headers, it didn't run one bit better than the 301. My wife had a stock Pontiac 350 in her 78 Firebird that could run circles around it, even with all the emission stuff hooked up and A/C on. Go with one of the Pontiac mills if possible.  

groder67 groder67
New User | Posts: 3 | Joined: 05/11
Posted: 05/30/11
07:00 AM

I really hadn't thought far enough ahead to realize the differences from the Chevy engine to the Pontiac.  I definitely will not go with a Chevy engine.  There was a 400 Pontiac engine and trans combo listed on Craigs List a couple of weeks ago.  I will have to give that guy a call and see if he still has it.  

Brazil Brazil
Addict | Posts: 3945 | Joined: 06/09
Posted: 05/30/11
07:17 AM

I think you would be very happy with the 400 combo. Since it's on Craigs List I would grill the guy a little before commiting to it. A few questions would be:

What year is the block, pre 1974's are built stronger - not really that big a deal, but if you intend to set it up for racing, the engine experts could offer better advice depending on the year.

Does it have a 350 or 400 transmission? (the driveshaft length may have to be modified).

Can the guy guarentee that the block is not cracked? Just a few thoughts.
Good luck.
Wink  

idrivejunk idrivejunk
Addict | Posts: 5139 | Joined: 12/09
Posted: 05/30/11
08:02 AM

+1 Braz, theres a lot to look out for when scouting out a Pontiac 400 block to use.  
idrivejunk

Torqued400 Torqued400
Addict | Posts: 2479 | Joined: 10/08
Posted: 05/30/11
08:47 AM

+2   Best way would be find the whole car that you can drive, you know a 4-door ugly thing that don't smoke and don't miss. Maybe a working th350 trans that you can transplant engine and trans at the same time or stick with the trans you got. That way you have all the accessories and brackets to use if needed, well some of them anyway. IMO. -T  
"We build Excitement"

Pontiacman8 Pontiacman8
Moderator | Posts: 5775 | Joined: 02/08
Posted: 05/30/11
04:02 PM

If you deside to build the 301 here is a cam that I have used and it works well for the 301.
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1193&sb=0
Team that up with a 500cfm carb.,headers and a good flowing exhaust and a good free flowing air filter.

The 301 heads don't respond well to porting so in my opinion porting is a waste of money on 301 heads.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

groder67 groder67
New User | Posts: 3 | Joined: 05/11
Posted: 06/05/11
07:53 PM

Craigs List engine and transmission is a 400 engine with 400 trans that is currently in a 68 firebird.  I will be able to start it and hear it run.  The guy says it came from a late 70's Pontiac.  I am going to try to go take a look at it this week.  

barneyformula barneyformula
Addict | Posts: 3306 | Joined: 01/07
Posted: 06/06/11
04:52 AM

Be sure to check the numbers on the heads and block so you know what you are getting. There are casting and date numbers on the back near the distributor and bell housing and a stamped two-digit code on the passenger front of the block next to the timing cover. The heads have a cast number on the center exhaust port and possibly a stamped single digit number on a verticle pad below one of the valve cover bolts. These numbers tell us everything about the engine and if it is a good one or not.
Steve

PS: if the th350 trans in your car is in good working order (and you don't plan on building a monster 400) you can bolt your 400 to it as is and save the hassle of relocating the rear crossmember, shortening the driveshaft and finding the correct floor shift cable bracket, all of which you will need to do to install the th400. If you do buy the th400 as well, be sure to get the slip yoke from the driveshaft because it is a larger diameter than the th350 yoke with more splines.  
A little help... 'cause we don't all have to learn the hard way!

stillwell stillwell
Guru | Posts: 1335 | Joined: 01/09
Posted: 06/06/11
06:12 AM

If ur not into the purist of the t/a then have at it.400/th350 is a great combo in stock form.and like me add a few things and i'm a happy camper so enjoy ur t/a the way u want. Wink  
REAL CARS FUEL FROM THE BACK!

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