305 Build Up Questions / Plans

These are my plans on the build up of my 305. I want to do this because I want the baddest LO3 in town & I'm so sick of people saying that 305's suck! Before making recommendations please read my "goal" below!

So all that plan to bash the 305 stay away your wasting my time!

My goal- I want a awsome 305 that can take most rustangs. I'm mainly looking for a huge amount of torque.

Heads
Which of the following is my best option? What are the pros & cons?
1. Keep my stock heads and have them ported and polished
2. World Products Torquer 305 Heads
3. Edelbrock Performer Centerbolts w/ 60cc Chambers
4. Vortecs

Intake
Which intake should I choose.
1. Edelbrock Performer TBI Intake
2. Holly Adapter plate for 4 bbl intake-- Then which intake should I use?
3. 14X3 Open Element
4. K&N or Cool Blue?

Camshaft
Which one is the best? What are the differences?
1. LT1
2. L98

Injection
Should I keep the stock TBI unit or go with TPI/Mini-Ram/ect. This may effect the intake manifold choice.
1. 454 TB
2. Holly 670 cfm TB
3. Stock with 2" and 350 injectors
4. What size if any TB spacer?

Rear End
1. $99 POSI
2. 3:42 Gears

Ignition
I have no clue what recommendations do you think should be made to stock?

Other
1. Hypertech Chip
2. 160* Thermostat for Summer and 180* in winter
3. Underdrive pully set-- which brand?

Suspension / Ect
What other mods are suggested? This is not the same as having a 383 dropped in so I shouldn't have to have subframe connectors right?

Thanks for the help!

 

I'll be following this topic - I wonder about some of these myself.

Heads
2. World Products Torquer 305 Heads

Intake
1. Edelbrock Performer TBI Intake
3. 14X3 Open Element w/ K&N

Camshaft
1. LT1

Injection
Don't know

Rear End
1. Posi with 3:73 Gears

Ignition
No idea.

Suspension / Ect
SFCs are recommended no matter what, but especially if you want the "baddest 305".

Exhaust: You'll need good headers, a high-flow cat, a good muffler and some wide pipes. Otherwise the mods to the engine won't be maximized.


My plan is to redo the suspension and the rear end before I start screwing with the engine. Just my personal preference - seems a waste to have a killer engine with a crappy suspension.

 

You still might have trouble with a 5 speed 302 stang even with all of IROCs plans. Those sticks are fast and can hit 13s very easily.

 

1. Vortec heads will give you the most potential to make power. Do you have to pass emissions?

2. Holley adaptor plate onto a Weiand Stealth intake manifold. It will generate a greater plenum volume for more upper RPM horsepower.

3. For the camshaft I'd recommend looking into the aftermarket if you want to make more power. The LT1 and L98 are factory cams and have a low duration and low lift. Sure they're cheap, but going cheap is not the idea when you want to build a decent engine. I'd recommend looking at Comp Cams or Lunati's lineup of 87-95 roller cams. Look for something over 210" of duration @ .050"

4. Go with the Holley 670 unit.

5. The Zexel-Torsen posi with 3.42 will work the best.

6. For the ignition you should definitely look into a higher output coil and some lower resistance wires.

7. Dont get the Hypertech chip. It's parameters are set for the stock cam, heads and intake. You're combination wont run right with that chip. You have to get your own specific chip burnt.

8. I wouldnt worry about subframe connectors right away. Definitely get some boxed rear control arms though and a stiffer panhard rod.

 

Hey man I'm with ya,

In another week I am ordering new heads and intake to put on my LO3. My setup with proper chip tuning should yield close to 325 hp. That's just with redoing the top end. After that I plan on buying the 335 stroker kit for 599, it's supposed to be worth 115 hp by it's self. I know 90% of people are going to disagree with a stroker kit adding that much power, but I'm just quoting the add.

Here's my planned setup:
305 TBI
Vortec Heads milled down to 56cc w/thin head gasket should yield about 10:1 compression or a little more
Edelbrock Performer RPM Vortec intake with a tbi adapter plate
Intake gasket matched to heads
LT1 cam w/ stock rockers
Custom prom

I am hoping for a little over 300 hp with this half of the setup.

Then comes the stroker kit, at it's "advertised" gain, should give me a 305 block that produces around 400 hp with a TBI setup.

Bring on the haters!

 

HEADS:
S/R Torquers

INTAKE:
Edelbrock TBI

CAMSHAFT:
LT1

INJECTION:
Ulimate TBI mods (should be enough even w/ this build-up)

REAR END:
SLP Posi w/ 3.42's

IGNITION:
MSD Cap, Rotor, Wires and Coil w/ AC Delco Rapidfire plugs w/ a .045 gap (stock is .035)

OTHER:
180* T-stat year round
Custom burned chip from Wright (last thing you should do)
Z-rated tires

SUSPENSION:
Spohn SFC, LCA's w/ Relocation Brackets, Panhard Bar and Wonderbar

The only thing I have in reservation is that the injectors on your stock unit might, and I stress MIGHT, not be enough, but even so, I think if you just replace the injectors with some ones from a 350 TBI, you should be fine.

 

OK So Here is What I've decided so far-

Votec Heads- I gotta get the 305 ones right- because the 350's won't work(too many cc's?) Milled to 56cc

Weiand Part Number 8016 Stealth Intake Manifold this will work correct? "Chevrolet 262, 283, 305, 307, 327, 350, 400 V-8; 1957-86 All Models; 1987-Later w/ Aluminum Heads "

POSi With 3:42's still not sure which brand to get.


And there is no emmissions here in MN:lala:

 

GM Motives are a good choice....that's what I'm going with.

 

Don't go with the 305 Vortec heads. They're missing some key power producing features that the L31 350 ones have. Just grab a set of 350 ones and mill them to 58cc.

I'd personally go with PN# 7525 but either intake will work just fine. However the Vortecs use a different intake pattern than the one listed for the intake manifold. So when you're gettin the heads milled, just get them drilled for the 57-86 intake pattern.

 

Thanks alot for your help iroc22

I've also decided on SLP's Zexel-Torsen POSI diff. Now I have to choose the gears. 3:42's- now I can get them for fairly cheap on eBay

 

I just got the '98 RS and it has the 305 TBI so this thread is interesting to me too. If I can get the motor to about LT1 territory while staying N/A and emissions legal, that will be fine with me. If I can push it further that is fine too but I would really like to keep it N/A and emissions legal.

First thing I am going to do though is build up the suspension and transmission and all that good stuff before I really tear into the motor or anything.

Thanks in advance for all the help.

 

:lala:Welcome!:lala:

You should not have to do as much to the suspension / tranny as you would with other motor swaps. I'm going to get SFC's and a Strut tower brace.

 

98' RS w/ a TBI

89' RS w/ a TBI

 

Sorry, its late and I get dislexate (sp?) when I'm tired (nor can I spell).

 

i know this a old thread and i wanna know what u did but i still give my idea.
heads-
-vortech heads are not a good idea on a 305. they are 64cc heads and the 305 heads are 56-58cc putting these on will lower your compression to 7.5:1 or so
-stock heads- get them ported and pholished along w/ 1.94" intake valves and 1.5" exhaust vales, have them milled for 56cc and 3 angle valve job, these will do the trick, but u have an LO3 so i dunno about those heads, mybe a set of LB9 heads would be better.
-World Products Torquer heads are a nice product and will do the job good, and not tobad on the pocket ethier 800 for the pair
-edlebrock heads, 60cc heads kinda big on a 305(8.5:1 compression) also not the best dollar value, 1100 for the set and will flow just as good as a set of world heads or reworked stock heads.
my vote is for the world heads

-intake-
get ride of tbi, if u want some bottom end tq. i say get the tpi, but u are looking at close to 2500 for a setup like that but u can go w/ a good manifold and a good carb.(i don't know much about carbs and manifolds cause i'ma tpi guy)but i vote for the carb setup

-camshaft-
none of the above, the ramjet cam works very well in 305tpi's but witha setup like this an lt1 or l98 cam won't unleash its ll potential imo, the ram jet is .431/.451 i would also get new lifters,pushrods and timing chain.(gm performance parts will be more than plently)

-i agree with the posi rear and 3:43 gears. if your trying to make a motor w/ tq 3:73's won't really help that. some 3:43's will run just as fast and save u gas.

-igition-
this is all a matter of perfrence they all the the same, i like msd, i don't think u need a box but it can never hurt, also a good distbuter will help. a high current coil and a good set of wires. also get some i have msd 8.5mm super conductor wires and they are great, nice thick duable a good product along w/ the rest of my msd products


other things that i think would help is,
-spohn LCA's w/ relocation brakets
-2500stall converter
-spohn subframe connectors
-transgo shift kit
-100shot(only if the bottom end is replaced or still solid)

w/ all the listed mods that i think would work good should put u into the 13.60's range w/ 60' 1.95 w/ good traction a set f et streets or drag radials.

 

Sorry if I'm wasting your time by chiming in but consider the following facts:


302 Ford 4.00 Bore


305 Chevy 3.875 Bore


350 Chevy 4.00 Bore


There is a pretty lenghty thread I started in the Drag Racing Forum with lots of information. Knowing what I now know about the 302 The solution to your goal is quite simple.

 

very true, but most people allready know this cause us 305 people have heard a couple thousand times

 

Underdogs are great in the movies because we all want the underdog to prevail... But reaility is something different altoghter.

I am not trying to dash away anyone's dreams of building the ultimate L03. Just realize that the 305 was not designed or manufactured to be a platform for high performance use. It is a VERY good and reliable motor for what it was intended for and that's about it.


I just hate for someone to invest all the time, effort, and money only to see there dreams reflecting on the tail lights of a Mustang with similar mods...

 

 

i understand what your sayin, but somepeople have to work wit what they have, i do agree with you that he could build a 350 for what hes gonna spend on this 350 that will most likely be faster, don't get me wrong, i love 350's but a 305tbi vs any well tuned mild 350 will lose horribly. now a 305tpi that has a *** working setup will give it a run for its money. thats al i'm saying. a 305tpi that has heas,ported intake,cam, and exhaust not be that much slwer than a l98 w/ similar mods. but to build an LO3 i dunno if thats worth it. imo

 

Just thought I would chime in with the whole 350 vs 305 vs 302 arguement.

With the 4.000" bore that the 350's and the 302's have, you can run larger valve heads. The engine will breathe better and you will have more performance potential.

But hey, its your car, do what you want to do. All we can really do is give you our opinion.

Do you guys think he would be better off running a LT4 cam instead of the LT1 or L98?

 

FRMULA88, do you realize that you have the wrong bore size for the 305? It's worse than it looks, it's only 3.750" which make air flow a bigger problem.

Steve

 

Working with what you have is called "penny wise"

Spending money on something that will not work much better is called "dollar foolish"

350 cores are not that expensive...

Removing a motor is not that hard, it seems like a daunting task but its pretty straightforward. By the time you remove all the parts your replacing out of the 305 you will have the shortblock block sitting in the framerails anyway.

I'll leave this thread with one last cliche

"You can lead a horse to water but you can't make him drink".

Good Luck

 

oops my bad...

that's right the bores are a whole 1/4" smaller aren't they

 

i totally agree but thats not what the thread is about. all i'm saying is that i'm working with what i have, i have a 305, until i get some cash i will get a 350. but for now i will work with a 305. i'm only doing mods to her that i can bring ova to a 350 someday, thats why the 305 short block isn't being touched.
oh bout the valves. i agree but i only wanna tip 300, so 2.02" valves won't do me much more than 1.95". and 1.95" valves with a to get my lb9 heads reworked isn't nealy as much as new heads for a 350 or a whole 350short block

 

im pretty content with my 305s performance, and since it dusts a lot of the 5.7s with the same mods, its good enough for me. its obvious a 350 has more potential, if u think ur tellin all us 305 guys somethin new, ur a bout the millionth person to have said that.

just cause its not a 350 doesnt mean its worthless, u wanna tell people about displacement, talk to the ricers with their 4 bangers, but ud be better off spendin that time gettin ur 350 to go because those damn little 4 bangers are catchin up to us quick!

u can say what u want about displacement, but some of these smaller displacement cars are gonna sneak up on u, they can and will make good power.

if ur gonna say a 305 is worthless cause its not a 350 then u might as well say a 350 is worthless cause its not a 400 sbc, etc etc

 

Um i kinda have 2 agree with the 305TBI is kinda junk, and yes I own one, every mod I have done, except 4 my PROM chip (which I got because I hated that speed limiter more than life itself) I can use with the 350 I am planning on buying in the future. Just not enough potential, its all been exaust and suspension work for me, being 17 I can not afford a 350 yet and will buy one after basic. My next mod will be nitrous, on slicks should put me mid-hi 13s. For an all stock TBI with nitrous I can not say I am disappointed the least bit. Under 5 grand put into a 13 sec car aint bad guys. Oh ya that includes the cost of the car itself. 3rd gens are great platforms to build on weather u have a carb 305, TBI/TPI 305, TPI 350. But yes I realize that working on my 305 is kind of useless and I have worked my way around it and will see 13s when I get my nitrous. :lala: Yes I am pleased, PS v6ers suck

 

Building a small engine to put out big numbers always intrigued me. If it was not for emissions I might have done it myself. Thats why I bought 454TBI I say build the 305, Itll be that much more respect when you win, also your scapegoat when you lose.


Charlo

 

2.02 intakes will not fit a 305. If they did, it would put the power in the 6500 range. 1.94's are perfect for a 350, and agressive for a 305.

I would not get heads for the 305. Dont get me wrong, the stockers suck. But the CC size will be too small for a 350 swap later on down the road. It would put your compression through the roof and I dont think you would get good flow with them.

I would get mostly bolt ons for now, maybe a cam (I love my LT4 so far. ) and wait for the 350 and do the major stuff to that.

 

Ya what I said.