1980 pontiac trans am question
 

Okay I bought a 1980 305 trans am with plans to twin turbo it homemade style, do a custom exhaust with the car gutted. I plan on hopefully putting out around 350 horses and 400 lbs/ft. I would like to if possible run mid to low 13's with street tires and the stock auto tranny. Is this a reasonable horsepower goal or are my sights too high for a stock motor besides the turbos? Also are the turbo's from the 301 turbo trans ams any good does anyone have experience with them? And can I just rotate the turbo on the stock turbo manifold from being a right hand manifold so I can put it on the left side instead?

Re: 1980 pontiac trans am question
 

forget the turbos, drop in a 6.6L NA and go faster.

Re: 1980 pontiac trans am question
 

bone is true on that statement. even a 454 will be good for that TA. im actually putting mine back together to sell it, but keeping my built 350 thats in it. a 350 will wake the car up for sure. the stock high output 305(as they call it) only makes 195 hp i believe from the factory. you can tt the thing, but wont be that great of an engine once all is said and done. thats why i said bye bye to my 305.

Re: 1980 pontiac trans am question
 

mild built 355's put out 350hp.............lol

Re: 1980 pontiac trans am question
 

Poncho 301 was a joke, a really bad one at that!

Re: 1980 pontiac trans am question
 

The 301 manifold will not bolt on to your 305 because your 305 is a chevy motor and the 301 is a pontiac motor. You will need to use either your stock manifolds or make some headers work. There are plenty of other turbos that are alot better than those 301 turbos. You should be able to get some good condition t3 turbos for cheap.

Re: 1980 pontiac trans am question
 

guys I have thought about the 454 but I wanna see how much power I can push from this 305 for cheap until it blows up or until I get greedy and start going for more power. This is a straight drag car. The only thing is I really wish it was manual but that is something I won't fool with til I do swap the motor. Your probably right the t3's would work way better for this motor and push more cfm than the turds they put on the 301. As for the manifolds not bolting up this is a pontiac motor. Pontiac offered the 301 turbo, 301 n/a, and 305 that year in the Trans Ams why they would offer 3 different variations of the same motor is beyond me but hey whatever. No matter what motor I do end up with in the end it won't be N/A I decided that a long time ago. And stupid question but I have yet to ever doa twin turbo setup but when running an intercooler can I weld like a y-pipe on one side of the intercooler so the air from both turbos goes in one side than run one 3" pipe out to the intake manifold?

Re: 1980 pontiac trans am question
 

yes you can do that idea with the intercooler. You can also buy dual inlet/outlet intercoolers too, just do whatever way will make routing the piping easiest. And the 305 might not make much power, but they are pretty stout engines and run pretty much forever if you take care of them. Give it a whirl with the 305. Any turbo setup you build for it would be a direct swap onto a 350 if you decide to go with a swap later

Re: 1980 pontiac trans am question
 

true that. Best part of the chevy small blocks parts swappability. I think I just made up a word. yeah this motor has only 78,000 all original miles so I'm guessing it is a good turbo setup for now. I don't know why but I would love to stick with the 305 even if I build one up from one of the newer camaros with the fuel injection and then swap it in and throw the kit I build on there. I have a buddy who has a 93 firebird with the 350 and 6 speed gear box, he might be selling it soon and told me that he would give me a discount if let me him help swap the 350 and 6 speed into my car.

Re: 1980 pontiac trans am question
 

better yet sell it and buy a crx :y

Re: 1980 pontiac trans am question
 

and put a 350 in it rwd ftw

Re: 1980 pontiac trans am question
 

O yea :y

Re: 1980 pontiac trans am question
 

the 305's (or chevy 5liter) was a terrible engine
i say that if you sold the engine complete with tranny
and then just got a junkyard bigblock from any of the big 3
like a 390,454,460 whatever you can find in the junkyard or craigslist that came out of a large truck or suv
(you might even be able to buy an older truck with a bigblock but rusty as ---- for $400-500 then take the engine and tranny and scrapp the rest and sell the 305 and odds are you will make money on the deal)

as for 13's i say if you get a good tranny and a $50 shift kit (like a turbo 350/400)
a nice bigblock (say 325hp and 365ft-lbs)
a 125shot of nitrous and some 10.5inch slicks and i think you would be suprized to be running between 11.3-12.5 depending on the engine and how bad it is
me and friend built a 5liter fox mustang that we tried to get in the 10's
ended up with an 11.43 and only made 4passes but it was a stock fox with 183k miles when he bought the car and total of buying the car and all the ---- to make it go fast was less than 2k, we just put on an ebay shift kit,nitrous,and some used slicks
he swaped the 5liter out about a week ago and threw in a ford 460 out of an old lincoln and threw on a 175shot plate and 10.5 inch slicks and it has a built tranny
he still has less than 5k in the car but it now runs 10.6's all day on spray and 11.2's on motor
he has plans of 4:11's trying to hit 10.5's on spray and 10.999 on motor but you never know
oh and the engine is stock except for a 232cam and edelbtock intake manny
it dynoed 341whp on motor (and 428ft-lbs) and on spray it made 572whp and 701ft-lbs (and with the spray it pulls to the 6500rpm the cam is made for, tho it makes peak power at 5400rpm and torque at 3600rpm)

Re: 1980 pontiac trans am question
 

lol why was the 305 a terrible engine? They don't make much power stock, but they will run forever. and ever. cornfuzed, you wouldn't look like such an idiot all the time if you didn't make such broad and definite statements about everything.

Re: 1980 pontiac trans am question
 

dude show me a 305 that ran to 100k miles without blowing out a hg
or would rev past 5500rpm?

i know they suck i have worked on a couple, and it's not 195hp they were rated at it was 165hp but like 240ft-lbs
basicly they are a truck motor

Re: 1980 pontiac trans am question
 

You Sir are an idiot. I know of several.

Please stop posting and showing your ignorance.

Re: 1980 pontiac trans am question
 

hey newbie, shut the ---- up you only have 21posts
just like at the six flags you must be... tall to ride the ride
if not just watch and shut the ---- up

Re: 1980 pontiac trans am question
 

#1, I've been here a hell of a lot longer then you.

#2, Your the newb from reading your posts.

#3, I have ---- more horsepower then you have ever built.

#4, that is all bitch. Now shut me the ---- up.

Re: 1980 pontiac trans am question
 

Just let him do a HMT setup and blow the 305 while he builds a smc or bigblock. Before the 305, 70-80k was decent before refreshing the motor, but again that's with carbs. Why don't you all stop bitching about if a 25yr old motor design in better than a 50yr old design and start brainstorming what he should use.

I vote for two 14b turbos, since they can give up 240whp on a D16 with moderate boost. They'd spool decent, be cheap, and will work fine if you weld dsm flanges on chevy shorty headers. I'd use a th350 or 400 if you can, get it rebuild w/converter & shiftkit for $300 total, and it will last a long time. As for fuel/ign, I'm clueless what works best on cars from the early 80's.

Re: 1980 pontiac trans am question
 

I'd rather find a couple garrett 42/48's for a cheap build. 14b's seem too small to me, but then again I've never had one.

And cornfuzed...
My friend's father's van has over 200k on the stock, never rebuilt 305.
My friend's monte carlo had a 305 w/~150k and a lot of raping before being swapped out in perfect health in favor of a built 350
and i know multiple other people w/305's that are perfectly reliable and high in miles.

They last forever because they are such low compression and make relatively little power for their displacement

Re: 1980 pontiac trans am question
 

Okay first of all who said I give a ---- about if this motor is good or not in fact I am pretty sure I said I am gonna beat the ---- out of it til it blows up then swap in a 350 or 454 with a manual tranny and build the motor. But as of right now I have a 301 actually I made a mistake. I thought it had the 305. but it is the 4.9 liter. It puts out nothing when it comes to power as far as v8's go and I may strangle myself with my speedo cable if I ever get beat in the quarter by any ford, and right now I am pretty sure I will get owned. But anyways, I was thinking about experimenting a little and looking into how toyota did the twin turbo setup on the supras with the whole one turbo helping spool the other idea and try something like that. Run a t25 or something a bit bigger and have it help spool a t3 if I can make it work. We will see. But right now I haven't touched the car my dad says he wants to buy the car from me. And for the guy who said sell it and buy a rex. I have a 91 si on my radar. I have always wanted a rex since I was a kid.

As for the T/A should I keep it that is my plan for now. As for anyone who disses on the GM small blocks I challenge them to show me a V8 that lasts as long. Chevy is like the honda of the 60's, 70's, and 80's. Everyone has owned one at one point and every little thing you could ever wanna do to it has been done which makes it really easy to find parts for it cheap as hell if you can't make it for yourself.

Re: 1980 pontiac trans am question
 

I know I haven't made my intro post yet but I am waiting untill I get my project done untill I do so. I just thought these links would help.

http://www.toohighpsi.com/index.htm
http://www.skulte.com/turbo.html
http://www.ttz28.com/

Re: 1980 pontiac trans am question
 

i don't think 2 14b's woud flow enough cfm on that engine (being a 305cid is 5.0l so half that is 2.5L on either side and the 14b came stock on 2.0l mitsu's)
i think either 2 18g turbos or a single 20g, both seem like they would spool quick enough and would give an overall power limit of abut 450hp and the 305 will blow up just thinking about 450hp so on low boost it should be fine

Re: 1980 pontiac trans am question
 

:6 Cornfuzed, shut the ---- up

Re: 1980 pontiac trans am question
 

lol cornfuzed owned : case# 985547458822565426985268422

Re: 1980 pontiac trans am question
 

Vote me for HMT presidente

Re: 1980 pontiac trans am question
 

Well like I said my current plan right now is wait and see what my Dad decides. If he chooses not to buy it I will do a twin turbo setup with a t28 or so and something like a t3/t4 or just a t4 for the big turbo much like the twin turbo setup on the Supras. Besides anyone who says 305's or 350's won't go for a ton of miles my dad had a fullsize van that we used to take on yearly trips out to Illinois and back for like 8 years straight. I think when we sold it the van had over 180,000 miles on the untouched 305. At least I think it was a 305 I was like 10 when we sold it. But the guy we sold it to continued to take it on trips but to Michigan this time twice yearly for the next 4 years and it was still running great untouched when he sold it. I don't know what has happened to it since then but when it was sold it was close to 225,000 miles. So there is one first hand impression of any chevy small block. I am not looking at this motor and thinking it is a beast I am looking at it and seeing a car that will maybe make 14 or 15 second quarter mile passes. This car is my toy. I want to at least run 13's or lower if possible. Its not like I am going to daily drive a car that is twin turboed with a carb tune. I wouldn't trust it that much. I will be putting hardly any miles on this motor so how long the motor lasts isn't an issue at all.

Re: 1980 pontiac trans am question
 

only cause you start rediculous posts, and ---- on EVERYONE'S threads with worthless/incorrect input.

with that being said, the 305 does suck.

it has serious quench problems and doesnt promote anywhere near an even burn. not even positive pressure at the end of the intake stroke (i.e. boost) would help it overcome that. cyl filling is ----. they leak from the rear main even when new, 2 bolt mains ftl, the worst example of a v8 i can think of, hell even an olds 307 is better than that...
the only positive you have going is it started life as a v8 car (no changing motor mnt pads, can technically run your tranny with a 350 but it wont live long). go get a 350 from a junkyard for $100 and a full rebuild kit (chevy kits have EVERYTHING for like $17). rebuild it to stock and low boost it. get a stall converter and some gears too, then it will be tons more fun than you have now.

Re: 1980 pontiac trans am question
 

Go to www.turbomustangs.com, and go in the gm section. That will answer any questions you might have. Any of the 14bs, t25, and .42/.48 will not flow enough and it will fall on its face. You will need at least .63 housings for it to flow half decent. 2 grand national turbos would work good for the 305. Alot of local guys use the ching chong .63/.50 internally gated turbos off ebay. SSAC makes twin turbo manifolds for your 305 motor and they hold up better than the ones for the hondas. Another possibility would be a single T4 T04E turbo off of a diesel truck or if you want to spend a little bit more go with a Master Power T4 T-70. Those turbo's are good for a single setup on a small block 305. Your hp goals are fairly realistic for the 305 but with a 350 you could do alot more. You should be ably to get into the 12's. There are a good number of people on that site with mild 350 builds with ching chong turbos goin in the mid 10's all day long. You will need an upgraded fuel punp (electric aeromotive), boost referrence fpr, and a blow through carb setup or convert to efi. If you're interested in efi, a tpi woulld be easy to do a build with using megasquirt to tune it. Another thing will be some sort of a stall converter. This will help with spoolong turbos. If you need any help shoot me a pm and I'll help the best I can.

Re: 1980 pontiac trans am question
 

HOW MANY TIMES MUST I POINT OUT I DO NOT CARE HOW GOOD THIS MOTOR IS. IT WILL BE BEAT TO HELL UNTIL IT BLOWS UP AND I WILL THEN SWAP IN A 350 or 454. I am not gonna waste time going to buy a motor at the moment. I wanna experiment with the crappy motor I have now and see what puts out good power and tweak my setup a bunch until I find something I like then go with another motor. I am also gonna buy my time til I find a killer deal on the motors I stated above. Now kill this talk about how good this motor is cause I don't care. Trust me I know it is a piece of ----. If it had any balls what-so-ever I would just keep it and build it up but it puts out like 195 horses or something. That will not cut it. Not now, not tomorrow, not ever.