I know a guy that is going to build a sleeper. As such, he wants to use the factory 305 TBI. He wants about 400 hp from it. I was just wanting to see if this was feasable. I know that if you throw enough money at an idea, then it is possible.

prob Nitrious will be his best bet and alot of tuning. other will chime in, and prob say just get a 350 but if hes dead set on the 305, he better be ready to lay out some cash

I was saying the same, but he is stuck on the 305. Going for stock sleeper. I say LS1 or LS2. He is doing NO2, but I think that is in addition to the 400. I don't know for sure.

If he can pull this off I`LL pay too this this in person.

unless some takes out a book adn runs the castin numbers off the block, they cant tell the difference between a 350 or 305 motor. I.E. i kno a kid who bought a SBC motor off ebay, seller claimed it was a 350, turned out to be a 305 outta a monte ss. but we didnt kno untill we ran the numbers ourself

I know you can't tell the difference from the outside. I say 350. He say rebuild 305 with a 335 stroker kit....

Buy an LO5 350 from a GM Truck, stroke it to a 383, and you'll make the 400 mark no problem with a good tune

That is what I planned to do. But, now, I think I am going to be stupid and save up and try to get an LS1 or LS2, do some head work, maybe change the cam, etc and shoot for like 450s.
But for now, since I am in college, I plan to get Vortec heads with the big valves, a LT1 hot-cam, ultimate modded TB and 350 injectors. Run that till I am out of school, then do the LSX.

400 seems doable. its not that huge of a number. with the right head and cam package plus the supporting mods, i say 400 plus could be doable. just gotta know what to do.

I am making about 370 as we speak. I could probably be around 400 FWHP. If I used a newer but better roller camshaft (I have the old L82 stick), good 1 7/8 x 3 headers or Thorley Tri-Ys(Flowtech 11500 now 1 5/8 x 3"), dual 3" exhaust (2 1/4 now), and a dual snorkel air cleaner with cold air.

I almost get shivers each time I see your posts, Fast355

Incredible

Have any dyno runs?

A 400 hp 305 wont be a sleeper, concidering the cam it 'll need to make that power.

The cam will make it sound consideribly meaner than stock. Unless he uses a quiet exhaust, but those are ussualy restrictive, aren't they?

I told him a LT1 would be his best bet. Your not going to see the motor as much as the rest of the car. And most people wouldn't even know what they were looking at. After all, who is going to jump out and take a peak under the hood before you run him at a street light?

Maybe I'm just used to HP talk with newer cars, but c'mon, use RWHP numbers please.


Sleeper + 305 + 400hp = Never going to happen

Not unless you are on the bottle and you hid the nitrous system very well....

As long as he's got $$$ and wants it to be a sleeper and make big power. Go with a LSx engine...
Heads/cam car will make an EASY 400 RWHP

My van engine looks stock and sounds near stock. The L82 cam sounds about the same as a L69 cam does, maybe just a hint more lope. With the ported cast iron manifolds, single in dual out 70 series big block flowmaster and high flow cat it is very quiet and not very restrictive compared to most other performance exhaust systems(1-2 lbs backpressure at most). The full exhaust and tuned TBI help keep most of the lope out of the engine. It idles dead smooth at 600 rpm with a great sound. Its a 305 with an exhaust sound.

My old setup with open cutouts and headers made 300 RWHP @ 6,200 and 325 ft/lbs @ 3,500 rpm. Through the mufflers it made 272 RWHP @ 5,900 and 315 ft/lbs @ 3,350.

With the crane roller cam I have, your above equation could very well turn into a reality.

I'll believe it when I see it, and hear it, cuz audible lope doesn't equal sleeper...

And are you saying a Crane roller cam swap is going to give you 120+ more HP?

The aduible lope maybe an exageration, it was factory on this engine. It really was, no joke. Sounds just like a LT1 camaro or vette when stock. The L69 cam already has a hint of lope to it. The L82 cam idles a little higher and has a sound that is VERY close to a L69. It also sounds very similar to the old 300 HP 327/350 of the 1960s. It sounds VERY close to stock.

If you have been reading the post I was at 272 RWHP though the mufflers which is roughly 320 FWHP through the mufflers. Open headers and more RPM gave me a HP peak of 5,900 rpm where it was 302 RWHP. That is roughly 370 FWHP assuming a 18% driveline loss, with a HD fan clutch and 7 bladed mechanical fan no less. My 1/8 mile trap speed picked up nearly 5 mph with cast iron manifolds/cat/flowmaster/electric fans, vs. my previous with headers/40 series/mechanical fan. Part of the switch is due to Texas emissions standards changing AGAIN.

I said the crane cam would bump me up by about 30 FWHP. That is 400 FWHP, the original poster made no mention of where the 400 HP was, so I am going to assume the Flywheel/Flexplate.

The crane cam I am stepping up to makes NO lope in a 350 TBI, but makes power all the way to 6,000 rpm with swirl ports. .488/.509 lift will do that especially when combined with a very tight seat-seat profile and moderate duration at .050.

I ran the 9.89 @ 69.08.



That is in the 5,300 lbs behemoth.

I ran it at the track Friday night and got one pass. I spun the tires all the way through 1st gear and got rubber going into 2nd as well.
I cut a horrid .931 R/T (I must have been asleep)
60' =2.42s (No traction)
330'=6.57s @ 57.4
660'=9.96s @ 73.9
1320'=15.5 @ 88.7

Here are some recent changes.
http://thirdgen.org/techbb2/showthre...hreadid=333368

This page is slightly dated
http://www.cardomain.com/ride/634172

I think that the guy with the L03 is shooting for FWHP.
IF that heavy van can run 15.9s with a 305, I wonder what my car could cut with it? I have 3.23s, not 3.73s. So, I don't know.

The arguement about the sound is a real issue. If he wants a sleeper, then the sound will be an issue. In my opinion, a newer motor with a quieter exhaust would be les dedectible than the L03 with a larger cam. But, not having heard a cammed L03, I don't really know. Has anyone ever ran a LT1 cam in a TBI 305? I hear they make good power with a decent set of heads.

I have actually run a 15.5 @ 88.7 now. That is with the 3.73s and a 2,800 stall. Your 3.23 would roughly equate to my 3.73s as my tires are more than likely about 2" taller than yours. Tire size is a large factor in overall gearing. A taller tire takes more torque to turn and rolls farther with each revolution. That means that my RPM could very well be lower with 3.73s and a taller tire than your 3.23 and a lesser tire. Simple? No.

Theres a thing going on to get the fastest 5.0 $$$ hehe

I will let you all know at the end to see what the fastest run is out of all us (about 20). If your interested in the competition let me know.

I am sorry, but I am not exactly competitive. I could still tow you away at the end of the night though.

I need to get a sound clip up on the web to let you make up your own mind. Mine just sounds like a V8 with Flowmasters on it.

LOL..

May I ask why you build such a nice 305 in a van? I think its cool and all but why not in a lighter third gen and show all these guys on the forum how its done?

i'm all for it, build the 305. i like seeing something different, all you hear is 350 this and 350 that. Big deal basically a 305 is a 350 with smaller bores (less cubes). For all the people that want to argue that my last statement was wrong plz don't i understand most of the differences i'm just showing the main 1.

Anyways you can stroke the 305 to a 335 and i also saw a different stroker kit for it floating around the web to make it a 340 (probably was an overbore of the 335 kit i suspect but, don't remember) anyways put a decent grind roller cam some roller rockers, bigger valves and port a set of world product heads or vortecs and take it to the max......

I would most definetly say 400hp without a bottle or forced induction is possible.

Btw this isn't the first or the last time i'll say this but, kick azz van fast355.

(btw i'm partial to 305s if you haven't caught that yet lol). Mines a 305 and i'm starting to build a 305 on stands as we speak. I'm porting a set of 416 heads right now and will be buying a weiand stealth intake manifold, headman elite headers and installing roller rockers and a roller cam something close to a lt1 cam. I'm shooting for 250hp so we will see.

Its the original engine in the van. Numbers matching. It has good power and gets good mileage, need I say more. I have a feeling a 305 Malibu is in my future.

When I'm talking about horsepower, I'm talking about where it counts, RWHP.

I'll take your LS1 all day long in torque at the wheels which is where it counts. A 6.0 should be making more torque than me! I could pull it around the block with ease.

All motor listings are listed as crank power, not rear. Like my L03 is rated at 170, but 140-150 at the wheels. A 2006 Z06 Vette is rated ar 505, but like 400-420 make it to the wheels. The power at the wheels is different between an auto and a manual as well as the clucth torque converter in the trans, so all factory numbers are at the crank, not at the wheels. That is why people are estimating the power at the crank. A more realistic comparison to factory numbers.

I measure power at the crank as it provides more of a direct comparison. Exactly, my bigger ring gear, and larger driveline will eat MORE HP/TQ than a F-body driveline.

I'm about a nats *** away from dynoing (RWHP), and I promise you I'll post a graph or (if the dyno place sucks) numbers with more RWT then you're making.

With even less cubes too

But there will be some extra 'gases' going in to the motor

This is very true. If you want to compare two ENGINE'S power output and you are using completely different setups, you should dyno using a flywheel number. Where it gets etchy is when people start guestimating how much their drivetrain is eating. Let's be honest unless you do an engine dyno pull then do a RWHP dyno pull, you don't know how much loss you got...

Must have a 4.8. I have pulled my 26' pontoon boat with my dads 2004 Express with a 4.8. Out on the highway it has to drop to 2nd to pull the same hill that my combo pulls in OD. The converter clutch unlocks for a few seconds near the crest though on mine. I know I am about to get blasted for pulling in OD, but my tranny is BUILT w/ a Huge Cooler.

It would be kind of hard to do that without the juice. I am making 300 ft/lbs @ 2,000 RPM and up to 325 @ 3,350. The torque was still hanging on all the way to 5000. I made 300 ft/lbs from 2,000 to 5,000 RPM on a Mustang Dyno.

I have a TBI nitrous kit in my Closet as well as the Crane Roller cam. I am thinking 450+ RWTQ or a shattered U-Joint!

It'd be damn hard without the nitrous. The motor's great with a good bit of technolgy in it, but it's still a small displacement V8... I scratched the cam idear. Hopefully next summer (summer of 2007) I can throw in a cam/head 6.0L....

400+ RWTQ without the bottle
The tranny is going to blow into about 45734 pieces lol

Sounds Like a good plan!

Or you could be the next Parish and slap a huge turbo on the Built 6.0 and build you a 4L80E. 1000+ RWHP.

Before I built my 305 I actually looked into a 6.0 swap into mine. Just decided I wanted it back onto the road and to go with a simple swap as it was a direct replacement for the Broken Crank 355.

In my dreams...

Trucks are nice and all, but if I'm going to have a 1000+ RWHP, almost 1100 RWTQ combo; it's not going to be in a heavy brick (aka truck)...

Heres how hot rod built a 400hp 305

http://www.hioutput.com/tech/400hp/400hp.html

Way to wake up a 3 year old thread.

A big cam doesn't have to make the engine lope it all depends on the lobe separation the closer the lobe separation the more lopey it is like a 106 or 108 the farther apart the lobe separation is the less lopey like 112 or 114 separation I had a big cam and i wanted it to be lopey but it wasn't because I had 112 lobe separation I didn't find this out until after the fact but I know now its just the overlapping of the exhaust and intake valves that gives it that lopey idle and less fuel efficent but a little more power if its closer.

This is the direction I am likely going with too. Advertising fraud aside, HorsePower TV made 390hp and 40X lb-ft with a bone stock LQ4 with headers (through stock truck intake). Get ahold of an LQ9 (near 1.0 more CR) with an LS6 intake and you have a solid 400hp mill for around $2500.