Fast355

iTrader: (2)

I recently dyno'd my 305 TPI project that is currently in the 1983 G20 Van. After many builds, I have come to respect the little 305 and what it is capable of. When properly built they can turn out some HP.

EDIT--- to remove some confusion



I started out with a 2000 model factory roller cam 305 block from an Express. I got it cheap from a wrecked van and it had a ton of miles, but that didn't matter. I tore it down to the bare bock. I trashed many of the stock parts that were no longer needed such as the oil pump, timing chain, pistons, rings, etc. I had the block bored .030". The block was decked .010" to give me the proper .040" quench with a .028" thick 305 head gasket, going for all the compression I can get here. The crank was turned .010/.010. The PM rods were checked over and re-used. The heads were also re-surfaced and ported. They also had 1.94/1.60" valves installed in the freshly cut seat. Then built it up from there. Here are the specifications of the engine, links were applicable.

Pistons

Piston Rings

Head Gasket

Oil Pump

Windage Kit

The bearings are Speed-Pro Competition series all the way around. Oil clearance was on the tight side, but I wanted it that way so that I could run 5w20 synthetic oil. I have 60 psi of oil pressure running 5w20 Mobil One and a solid lower end.

I used a harmonic balancer cover, just in case the stock balancer decides it wants to come un-glued, it will be contained. I also used a SFI approved flexplate since it is sitting right under me.

GMPP 1.6:1 Self Aligning Roller Rockers

http://store.summitracing.com/partde...5&autoview=sku (Modified to my needs, ported and siamesed)

http://store.summitracing.com/partde...5&autoview=sku (Is the same as this edelbrock one, I ported it up nicely).

I know there are alot of parts missing from this list, but they are just generic smallblock stuff. Gaskets, seals, tin, etc.

Intake Valve

Exhaust Valves

The heads were setup for .510" lift and the appropriate springs were setup for the camshaft specs.

The ported 059 heads flow chart @ 28 in/h20 pressure drop

Lift-----Intake---Exhaust
.050------32------25
.100------65------60
.200-----130-----113
.300-----185-----157
.400-----218-----167
.500-----254-----175

Here are the camshaft specs of the Reed Custom Roller that I am running

260/264* @ .008, 208/212 @ .050, .480/.507" lift w 1.6:1 rockers, 112* LSA, 108* ICL.

It is running the SDPC Vortec intake base ported to both the heads and the SLP runners. The headers are Doug Thorley Tri-Ys running into dual 2 1/2" pipes. The injectors are GM issue 24 lb/hr LT1 units from a 1996 Camaro that have been ultrasonically cleaned. The stock fuel rails are there and the stock fuel pressure regulator was made adjustable and I am running 50 psi of fuel pressure. The 7730 ECM is running S-AUJP V4 with my own tuning in it. WOT timing is 30* @ 4,000 rpm and the Air/Fuel ratio is 12.3:1 @ wot.

tpi user

356 rwhp pretty good maybe a cam with alittle more lift an same duration might help alot with your heads that floww good at .500 lift but your cam is not even 500 lift an maybe alittle smaller injectors but your not sayin its runnin rich so it may be ok ,but those are pretty good numbers ,i like it

NatesZ/28

HOLY CRAP; THATS AWESOME

tpi user

i know almost better than most of the guys on this forum with 383s an 350s.
----------
are you sure your not messin with us? lol

Shadygrady

iTrader: (3)

Fast355 I thought I remembered you running the lt4 cam.That duration is the same but ur lift numbers are a little higher.If not the lt4,what cam is that?Those are impressive numbers for the displacment and the cam.Guess I need to get som head and intake port and upgrade work done.Then I need to tune like you.

Fast355

iTrader: (2)

Why would I be messing with you? Its real and it has pulled my 5,300# fullsize van (700r4, 2,800 rpm Yank Converter, 3.42 gears, and 29" tall P295/50/R17 tires) to a 14.6 @ 96.5 in the 1/4 mile.

These runs were made in Drive with the 700r4 shifting at 5,000-5,200 rpm, launching with wheelspin from 1,500 rpm. I think it has another 1/2 second in it atleast, judging by the 70-120 acceleration I made shifting @ 6K manually.

RT----.396
0060'--02.62
0330'--06.57 @ 59.73
0660'--09.82 @ 76.52
1000'--12.64 @ 88.78
1320'--14.63 @ 96.55

This is the van



Its progressed from a beefed up carbed 305 to getting a TBI setup.



It then traveled from a stock TBI 350 with bolt-ons up to a cammed, vortec head TBI 350 making 370 RWHP.



When the 350 popped, I rebuilt a stock L30 Vortec 305 and put 187 TBI heads and a production LT4 cam, then topped it with a stock TPI setup.



The newest setup only has two externally distinguishing features from the previous photo, SLP runners and the Vortec TPI base with its externally plumbed EGR. Otherwise it is all the same.

Here are some pictures of the camshaft and heads.







Here is a shot of the Thorley Tri-Y headers. They work awesome on a 305 pulling around some weight.



It does not run rich with the injectors and fuel pressure. If anything it could use a step up in injector size, but that would force me to run a lower fuel pressure. These injectors spray very nicely at 50 PSI. The finer spray pattern helps promote atomization which helps the engine deliver more power AND better fuel mileage. Cleaner emissions too, BTW.

Here are a couple of tuning pictures.

If you question the engines output, seriously consider the frontal area and drag and the speed it achieved in this screen shot. Also take notice that it took 10 seconds to accelerate from 67 to 126 mph, shifting 2-3 manually @ 6,000. This wasn't on a dyno. This number was achieve at road load. The 1-2 and 2-3 WOT shift points are too low with the stock GM fullsize van governor (5,000 rpm) in the transmission, but I am working on that after switching from the 3.08s the governor I had previously tweaked started acting very retarded.





When I first swapped the 305 in and started running it on TPI it DID have a LT4 production roller cam in it and ported 187 swirl port TBI heads. When I obtained the Vortec TPI base and ported the 059 Vortecs I had, I went with a custom grind cam. Its from Reed Cams, custom grind TM260/264hr12a2. It pulls great vacuum, idles smoothly in drive at 550 rpm, with the 2,800 rpm converter it jumps quickly up to its powerband, and pulls strongly past 6,000 rpm. The real kicker is I drive 20 miles a day in it and average 18-19 mpg, incedentally that is 2-3 mpg better than my stock "daily driver " 2006 Dodge Ram Quad Cab with the 4.7 gets. Ask me which one I drive more now, its a given. You couldn't ask for a better matching engine or drivetrain.

tpi user

relax i was kidding great job. just shows everyone what a well planned an thought out engine can produce. would make alot of 383 guys jealous i would imagine.alot of those guys would say why bother buildin a 305, you just proved why

Street Lethal

iTrader: (16)

....

tpi user

id like to see a pic of the intake ports an the combustion chamber if u dont mind.

Fast355

iTrader: (2)

Lol, definately came alive in the wheelspin department when I took the 3.08s out and put 3.42s in it.

This is how it used to run with the 3.08 gears, stock converter, stock TPI, 187 swirlies, and Production LT4 cam. Not terribly fast falling flat on its face above 4,500 and having 5,000 rpm WOT upshifts, but not too shabby for what it was either.

Guest

That about sums it up.

Fast355

iTrader: (2)

I am pretty sure I have some, let me dig around on my laptop.
----------
I was talking about the datalog showing 126 mph. That was road load, meaning moving vehicle. The 310 is wrapped in a fullsize G20 van, you do the math.

It has seen the dyno and the results were posted in the first post. Sorry for the lack of print-out, but the Excel spread sheet works fine.

Shadygrady

iTrader: (3)

That custom grind is very similar to the lt4 cam.Little more lift on the exhaust side,very slightly more duration and intake lift.The lift numbers are actually close to the zz4 cam.This is good for me cause hypotheticly I could reach these numbers If I can learn to tune,port heads and upgrade to slp/edlbdock intake then port them.Then bigger injectors.Oh yeah and better headers.I`ve been trying to dattalogg.I can do it but I have a tough time posting what i`m getting.Cant get it to upload right.I also dont even know what all I`m looking at or what it means.Been having a rough idle at start up,wants to stall and die and has a rough chpoey idle till it warms up or goes into closed loop.Then it runs fine.I`m just happy to see someone getting good numbers out of a 305.Got one on a stand for my truck and I know its possible but when you ask people questions all you get is get a 350/383/LS.

Guest

Thats precisely why I asked, no needed. First you say it was a dyno, then no. Its kind of hard to decipher highly unusual results when two different things are stated with no reference on either.

Fast355

iTrader: (2)

I was confused about what you were trying to say. What I was saying is that if you doubted the dyno numbers, maybe you wouldn't doubt the datalog that shows the aerodynamic brick flying along. It takes some power to do that, not that I condone doing it on a public road. It was 1 AM in NO traffic on a straight piece of road.

Guest

Street racer.

Maybe you should put a nose and wing on that thing, ala Daytona SuperBee.

Shadygrady

iTrader: (3)

The cam proll wasnt the biggest problem there.The stock tpi and the swirly heads probably what made it fall on its face above 4500.That new cam doesnt look that much differant to make a huge differance.

Fast355

iTrader: (2)

I did have some, a few were from ebay when I first started looking at the 059s, loaded them to my photobucket account and here they are. First one is stock chamber with the stock 1.84/1.50" valves. The second is the re-surfaced head with 1.94/1.60" valves in it.









Here are the intake ports, people always have said they suck, but they are the L31 design and flow about the same out of the box. The intake bowls need some work though.





Stock 059 Exhaust ports are every bit as weak as the L31s are.



059 Vortec complete casting number


----------
SHHHH!

If you want to call a SRT-4 Neon a race.

Fast355

iTrader: (2)

The wide LSA of the LT4 cam detracts from the mid-range performance. The LT4 cam always felt pretty sluggish through the mid-range, even where the factory TPI should have run out the strongest.

Shadygrady

iTrader: (3)

What is the lt4`s lsa,like 115?

Orr89RocZ

iTrader: (20)

those numbers are unreal given the heads/displacement and cam. That cam is tiny and its making 356whp??? Those heads only flow 250cfm and its making 356whp?? just doesnt add up

My head is spinning with this one

Fast355

iTrader: (2)

It doesn't take a huge cam or giant ports when you are only feeding 38.75 in3 a cylinder. A 383 is obviously going to take more airflow in an attempt to feed its 47.875 in3 per cylinder. That means I can get my torque and maintain it longer using the smaller parts. Being able to generate torque over a broader RPM band boosts my hp.

1989GTATransAm

iTrader: (3)

Wow that is impressive. Figuring a 20% drivetrain loss that works out to 445hp at the flywheel. Divide that by 310 cubic inches and that works out to 1.435 hp/ci. That is unheard of with a cam of only 208 degrees of duration. Congratulations. That is supercharger territory to get that much air through the motor in order to make that much power.

tshack

WOW! Thats very good. great dyno #s. Reed does great cams, my Dad sold a few here in Nor Cal years ago. I guess I should get some vortec heads. My comp cams 262HR-12 has very close specs, A little more on the exhaust side. okay you got my head going agian.

Guest

Have a sound clip?

tpi user

those l31 vortecs actually flow better tha gm fastburns which are a 210 cc port an 2.00 in int valve they are pretty good heads
----------
plus afr heads are makin what 280 at .600 lift an trickflows 195cc head is makin a measely 258cfm at 600 lift hell i think the sportsman 200cc head isnt flowin as good as a votec about the same maybe but thats it

Fast355

iTrader: (2)

L31 Vortec flows 239 CFM @ .500" right out of the box. The L30 head is about 235 @ .500" through a 1.84" intake valve. I would have thought the Fastburn flowed better than the 243 cfm they obtained with 210 CC ports. I know the Brodix IK180s flow about 255 cfm on the intake @ .500" through a 2.02" vavle. Their CNC 210s flow 278 cfm @ .500" but gets 290 cfm @ .700". Just goes to show that you can have a big port and you can have an efficient port. Typically the smaller the port, the better your lower lift flow numbers are going to be. A smaller port will out-perform a larger stagnant port on the street any day of the week.

Fast355

iTrader: (2)

I've got a video clip of it, didn't really get that hard into it (enough to get some wheel hop though) since I was on a city street. The windows are up and the air is blasting since its been hot and humid here lately. I didn't go over 1/2 throttle or 3,500 rpm. If you watch the speedo and listen for the chirp on the first 1-2 shift you can tell the 700r4 has more than a shift kit, lol. Since this video, I have also been able to find the $8D hack and figure out how to get the engine the AE it had been craving, so it no longer has the low-end bog taking off with moderate throttle. It was so starved for fuel from lack of AE that it would backfire when the throttle was stabbed to the floor from idle.

Orr89RocZ

iTrader: (20)

Oh i understand that, but still. Your numbers are just absolutely insane. My buddies 4.8 liter LSx motor was making around 340-350whp with a 224 cam and 5.3L heads which flow as much as yours.

I just find it hard to believe that combo made as much power as its doing. hp is hp, you need so much air and so much fuel to make a power number. For a smaller cylinder to make as much as a larger one, you have to wind it up higher inorder to go thru more air/fuel as a larger motor.

There are plenty of guys on here with upgraded TPI running 305's with similar cams but nobody is making those kind of numbers. There are guys with MUCH larger engines in general not making those numbers. LSX guys with small cams untuned are in the 360whp range and they flow tons of air thru the motor

Your build is a freak. This is one more reason i want a 305 now as a second car just because i have ideas for a build and i think i could make good numbers. But i wouldnt expect your numbers.

This was a dyno with the motor in the van... at the rear wheels correct? I'm just in shock.

If my 383 does only 400whp i'll be somewhat happy and i have 70 more cubes, MUCH bigger cam, and better heads to only make 40whp more???

Fast355

iTrader: (2)

I don't know of many 305 builders that are running over 10:1 compression in a mildly cammed iron headed engine either. The engine was in the van with all accessories including power steering and A/C installed. Electric fans though. It was running through a 2,800 rpm stalled 700r4 and GM 8.5" 10 bolt with 3.42 gears. When you do your build, pay attention to the small details. What others write-off as insignifigant can when added to other gains create a substantial gain. I have seen total seal gapless rings boost cranking compression by 20 psi and TQ by 15 ft/lbs across the board with NO other changes. Gains from oil control are HUGE, especially at high rpms. Pulling a healthy vacuum on the crankcase will help ring seal and cut down on windage losses in the rotating assembly. Changes in valve seat angles can reap good flow benifits. Degreeing the camshaft and spending the time to make sure it is timed as it is intended pays dividends as well. You also want to make sure that your quench distance is right on where it should be, this will speed the burn while keeping detonation away, which will allow you to run less timing and make more power.

4.8/5.3 heads are the same beast and a 224* cam is nothing to sneeze at although the person you quote probably could have made just as much power with a smaller cam. I put down nearly 390 RWHP with 350 using only a little more cam and a single plane manifold under a TBI.

1989GTATransAm

iTrader: (3)

"Pulling a healthy vacuum on the crankcase will help ring seal and cut down on windage losses in the rotating assembly. "

If you are using low tension rings. I'm not sure I would do that on a true street motor. I agree with everything you said. I have done what you have said and I not near the hp/ci ratio you are.

Fast355

iTrader: (2)

I do not have low-tension rings, but I do have an electric LT1 emissions air pump setup to draw about 7 in/hg on the crankcase @ WOT. It works as I saw 2-3 tenths of a second improvement in ET.

What kind of torque are you making though?

Also I don't know how correct the dynojet in question is, but the 14.63 @ 96.5 with a 2.62s 60' run shifting automatically at 5,200 means that I should still have plenty more in it. A 13 second pass from the 5,200 lbs van is probably achievable. Regardless its 310 CID and is making some pretty good power.

Orr89RocZ

iTrader: (20)

well i hope my 383 will put down 430-440whp then, because i've paid attention to detail by getting proper quench, custom cam thats degreed to spec, proper valve spring specs to control the cam's rpm range, etc

where those dyno numbers SAE corrected? still tho, i would have guess that combo to make 250-260 whp on a good day thats what my L98 HSR with stock longblock did.

Fast355

iTrader: (2)

Why couldn't your 383 put down 435+ RWHP?

The numbers WERE SAE corrected, so they were a little lower to begin with, how much, I don't know.

I ran a 350 TBI with out of the box Dart Iron Eagle 180s, a production LT1 roller cam, 9.5:1 compression, an Edelbrock 3704 TBI Performer, Stock exhaust manifolds, Stock Y-pipe, high flow 3" cat, and single 3" exhaust and still made 298 RWHP on 87 octane. With an edelbrock performer rpm intake, through an open cut-out, running 93 octane and an aggressive spark map, it made 326 RWHP.

Guest

If you are doing an SAE correction, you might want to check your calibration... because at 5300# and 96.5MPH, it doesnt add up. I dont think the short shift amounts to that much.

Fast355

iTrader: (2)

Quite possible. If you are trying to use one of those little trap speed, hp, weight calculators, don't bother. Try something like Cartest that simulates aerodynamics, gearing, drag, torque converter operation, etc. That program is on the money. The one line calculators are so far off its not funny when it comes to a vehicle with the size, frontal area, and aerodynamics of a van. Short shifts killing it worse than you think with the power curve it has, especially with the short first and tall 2nd gear ratios of the 700r4. I am thinking of putting a 4L80E into it and controlling the shift points with the TBI PCM. I am tired of going into the 700r4 to change shift-points. That and the 700r4s just don't seem to hold togather.

BadSS

I don't know about Cartest, but I do know Quarter Jr is on the money and I can't get your numbers to match up. Well,,, short shifting a 440rwhp @5500 powerplant in 5300# vehicle at 5000rpm,,,, with a 2200 stall speed and 6" wide tires matches up pretty close.

I don't see any converter flash on the dyno curve or any dips from where it drops off and the engine takes over. Hats off if you were able to match that up that smoothly.

Also, based on your track times
RT----.396
0060'--02.62
0330'--06.57 @ 59.73
0660'--09.82 @ 76.52
1000'--12.64 @ 88.78
1320'--14.63 @ 96.55

it took 8 seconds to go from 60 to 97, but you say it goes from 67 to 127 in ten seconds based on the data runs. One is off for sure.

I hope you're really doing what you say you are, but personally,,, I'd have to see it run on the track or make a pull on the dyno to believe it.

Orr89RocZ

iTrader: (20)

Well my 383 should be stout as similar engine specs show good numbers. 430 is in realm of possibility but i'm not gonna expect that power, i think 400whp is more in line of what to expect and be happy with. we'll see in a few more weeks i guess but that power is alot of power from a n/a small block i dont care what inches your running. Most 383 LT1 cars i've seen running near 6800 rpms are only making 430-440 whp and i dont expect to turn quite that high

And that TBI build is also impressive. My buddies 4200lb truck ran 98mph with a vortec headed LT1 roller cam 350 running a performer rpm intake with 750 carb. estimated near 300whp as well but thats with full exhaust. Are you sure your dyno's are calibrated right? Or maybe i need to have you tune my cars now on

RacerX13

I was kind of surprised to see that you were running a 7730 ECM instead of a TBI PCM. What made you choose one over the other?

Awesome results by the way. Thanks for sharing all the details with us-that's exactly what I come here to learn, and it is MUCH appreciated. Disregard the naysayers-you have given given them enough info to prove it if they are smart enough to put all the pieces together.

Fast355

iTrader: (2)

Gearing, Gearing, Gearing and RPM. I am not talking short shifting 500 rpm. This combo is still pulling at 6,300 rpm and probably would see best results shifting at 6,500. I have enough valve spring pressure to keep the roller lifters from floating until about 6,700.

The reason you don't see any converter spikes is the dyno was made with the TCC LOCKED. The pull started as soon as I could get it to stay in 3rd gear with a diesel governor in the transmission, which was around 2,400 rpm.

As far as the data runs, I held the engine out to about 6,300 rpm before letting it shift 2-3. If it shifts at 5,000 it shifts at about 70 mph and the engine bogs down to about 3,000 rpm then at 72 mph the converter force locks and drags it down even further.

I don't know where you are getting this 440 HP quote you keep coming up with. At 15% loss, I get 418 FWHP. The losses though an automatic transmission B-car are about 15%. A stock 260 HP LT1 dynos about 215 RWHP. The 700r4 and 4L60E are built the same and have the same losses. The B-car uses the same 10 bolt rear end design as the van. In fact transmission losses shouldn't even be a percent of power lost. They don't start drawing more HP the more power you put through them. Its a fixed loss that builds as the drivetrain gains speed. More RPM, more losses. So at peak torque the losses are fairly low and at top RPM they are highest.

Shadygrady

iTrader: (3)

It seems wild you`re still making power that high in the rpms even with a modded tpi system.Your tourqe curve is about what I expected but it still makes hp even a little past 6 grand or atleast up to it.Thats great.Is everything ported and gasket mayched?stock t.b.?Nevermind just saw your sig.

Shadygrady

iTrader: (3)

Mine seems to pull like crazy through the midrange.Not doubting your experience.3000 rpm`s or from 30 to 40 mph roll and punch it feels very strong.

tpi user

thats exactly what i say you dont lose more of a percentage loss because one engine makes 450 hp versus an engine that makes 400 hp its a fixed loss,it shouldnt be 20% on 550 hp engine an 20% for a 400 hp engine. the550 hp engine would lose 110hp an the 400 hpengine lose 90 the 550 engine is still transmitting power thru the same tranny an rear end. imo it should be a fixed number like 80 hp to go thru trans an rearend.this always seemed like a bunch of crap to me. like the ls7 puts out 505 hp but on engine dyno it puts out like 423 i think i read somewhere

Orr89RocZ

iTrader: (20)

hard to say what the losses would be, but a LT1 is not 260hp, its 300 reguardless of what car you put it in, and typical fbodys will dyno 240 with an auto and 260 with a manual. roughly 15% loss manual and 20% auto loss

what strikes me odd about this build is that LT4'sdont dyno this power yet they have similar heads/similar cam, and better flowing manifold. LT4 is around 330whp full bolt ons/exahust. Thats a 350 inch motor no doubt. I just cant figure out how a small bore 310 would beable to make those numbers

Whats the advertised duration on the cam if you dont mind me asking

Shadygrady

iTrader: (3)

260/264 I think he said.

Orr89RocZ

iTrader: (20)

I must of missed that, those figures are still kinda small. Idk, maybe its just one of the most efficient motors i've ever seen

1989GTATransAm

iTrader: (3)

"maybe its just one of the most efficient motors i've ever seen"

I have to agree with that statement. After reviewing everything I don't recall seeing a street motor this efficient.

Fast355

iTrader: (2)

The LT1 B/D body is 260 net flywheel hp, sorry they dyno neck and neck with a stock L31 vortec truck engine.

Orr89RocZ

iTrader: (20)

i wasnt sure if they got the same LT1 as the Y/F body, but now i recall the impala getting Iron head version that was rated abit less hp

tpi user

what strikes me odd about this build is that LT4'sdont dyno this power yet they have similar heads/similar cam, and better flowing manifold. LT4 is around 330whp full bolt ons/exahust. Thats a 350 inch motor no doubt. I just cant figure out how a small bore 310 would beable to match[/quote]
----------
this was from orr 89 he said this , iscrewde it all up tryin to quote him in my response im a dummy sorry. ok i agree with you on this orr an im puzzled also some special exhaust? i forget what he said . or maybe special tune? i dont get it