GofasterFirebird

iTrader: (3)

FYI

OK, so I got the 406 running this weekend. Please see sig for all my expensive parts. Drove it from Toledo, Ohio to Ft Wayne, Indiana (~130 miles) to break it in a bit. I used a best guess chip which was basically one that I borrowed from a member and slightly modded to what I thought was appropriate. I wasn't too concerned as long as my BLMs weren't bottomed/topped out as I had no intentions of engaging PE.

Things I expected to go differently:

It stayed cool with the stock TBI 305 radiator, water pump, underdrives and a single electric fan. I let it idle for 10 minutes and it reached steady state at 181 degrees. It was also 80 plus degrees out, so I cant complain. Anytime while driving it runs at 160. I guess I shouldn't have given any credit to the rumors about how 406s run hot. Also, the converted LT1 intake has no cooling issues with the remote mount t-stat.

The 11.0 compression and extra cubes made an otherwise large cam. (292 advertised 240 @.050) seem streetable. The idle is a bit lumpy but I have been doing city driving and it seems acceptably tame.

It got 21 mpg on on its' first drive. It was primarily highway, but I didnt have highway mode engaged and I am sure the engine is still tight. I have 3.70s but the overdrive cancels it out.


So, basically the drive went smooth which surprised me. It still has an off idle hesitation issue and some 118 BLMs but the above issues were not what I had anticipated

N8MAN1068

but how does it do on the track?

GofasterFirebird

iTrader: (3)

Well, I kinda just got it running so that was out of the question. What do you think it will do?

88TPI406GTA

I would hope high 11's with drag radials...mid 11's with great tuning, maybe slicks too...depends on your 60 ft times...

Fevre

More I read about the 400 the more I want one, a 427 sb just sounds .

Have fun and keep us up to date on your impressions with your set up.

85TPI400

The day you put a 400 in you car and drive around is the day most people say to themselves that they will never settle for a 350 or smaller engine again!

Spdfrk1990

so u think the tbi single fan would be fine with a 383 and did it hold vacume ok with that cam

GofasterFirebird

iTrader: (3)

Here is my cooling system:

Stock H20 pump
Stock TBI radiator and single fan
160 Tstat
March Underdrive


I dont see why a 383 wouldn't stay cool. Mine doesn't crest 180. Even in the 90 degree weather here. I think the alumimum heads might have something to do with the temperature staying low.

The power brakes work fine as well as the heater controls. It idles at 59 Kpa on the MAP sensor. I guess the extra cubes make up for the big cam.

ski_dwn_it

THey are a sweet engine aren't they? :hail:

Go the Tq of a BB and the look of a small block!

You should be mid-high 11s no doubt at about 377rwhp with no doubt.

As I have stated many times before. The cooling issues with these engines is a big myth. It comes from back then the radiators couldn't cool worth a darn. Todays cooling systems are far superior.

Enjoy the ride...Be sure to let us know about your track times.

Also don't be shy with the breakin. I believe in the old sang. Break it in like your going to run it! I had mine to the track well before 500 miles

They are sorta like a dog. If you baby then they become babies, if you beat them they grow up to be mean.

That may have not been 100% politacally correct for the animal lovers, but then again when have I ever been concerned with politcal correctness?

Good luck!

GofasterFirebird

iTrader: (3)

Ski,

What did you run the first time out? I am concerned to floor it too much because I haven't quite finished my WB circuit yet. What made you say 377 rwhp? I was thinking anywhere between 380 and 400.

Also, I was looking at my pulsewidths on the way to work today and I was seeing 10.6 @ 5300 rpms. I get that 100% DC is 11.3 ms. Is this correct? And how are you getting away with 24s!! What is your DC?

Scott_92RS

Ski, what kind of fuel are you running with that compression ratio? Would I have any problems running 11.3:1 on pump gas (92 or 93 octane) with my AFR 190s in my 406? I've heard mixed opinions on it.

ski_dwn_it

GoFaster,

yeah that put you at about 94% duty cycle. You want to crank up your FP before you start tuning.

My first times out were in not that great of air ~1800 DA and it turned 11.147@123. I have been to the track 3 other times with equal times.

The #24 pound injectors are going static at about 3600 RPM, so I recently have been rehashing my setup at a higher FP-55psi up from 43psi. The duty cycles are a ~81%. I have the part throttle tune on again, now I just need the time to return to the dyno for some more testing since the injectors are out of the gutter. I suspect the car will pick up another 15-25hp and ~40-50 FT-lbs at the wheels with the recent increase in pressure. Just have to get it out there to do it I guess. Time is short and the main deterant.

377rwhp is nothing to sneeze at. It was conservative, but I am not all that familiar with your setup. If you gave me some track times I would be able to get a much closer estimate.

Scott-

I think you are going to be pretty hard pressed to get away with 93/94 octane, and running it hard. What you have to realize. Is at the track I run either race gas or rocket fuel (toluene mixture) which takes care of any WOT detonation that you might get. I figure its added insurance. Not to mention is burns 100% cleaner than gas.

But anyways getting back to what I was saying. You can easily do anything with a good running one of these at 1/2 throttle,as most cars can do at WOT. Hell I had a pretty hopped up camaro try to pass me the one afternoon on a two lane road and I pulled away from him like he was standing still and I never even got close to WOT. And did not hear any pinging. That was on 94 octane. But yes on occasion if you get over zelous you will hear it clink alittle. But that is usually when you scared yourself, and are about to leave off anyways. LOL

Any questions you guys have let me know.

camarojoe

Wow Ski, I can't imagine my car burning the tires off with the slightest touch of the throttle like yours. That's the kind of response I want.

GofasterFirebird, how does your car run with just a little gas, can you break the tires lose in first with just a little gas? I remember reading that Jesse can practically smash any passenger's head against the headrest with just a little push of the pedal. Thats what I call having some torque. I'm seriously considering putting a 400 in my car that my dad just bought. He said he'd sell it to me, I'm just trying to figure out if I can afford it.

GofasterFirebird

iTrader: (3)

Sure, any time I am in first gear I can touch the throttle and spin. In second gear I can give it about 80 percent and spin. Granted, these are just Falken 255 radials. I do have battery relocation, and lcas, lowering brackets, spohn arm. But I definetyl have lots of torque. Now, if you already have a 383, I wouldn't build a new motor. What does your 383 run?

Ski, you are telling me that your injectors were static at 3600 and you continued to run them until 5500? So, 16.7 ms at 3600 and then 10.9 at 5500? To me this seems like the calculations are in error. I dont see a motor of your caliber not leaning out excessively. It makes me question how many times they fire or something. I don't know.

ski_dwn_it

GoFaster,

The firing scheme is something that was brought up and is a whole other topic that you don't want to start here or you will get murdered. LOL

Some are definately questioning the firing stategies, and so am I. Testing it is another thing. You need a duel occilicscope to measure the pulse widths, unfortunately finding one and having it available at the dyno is a problem all of its own.

My engine makes good power all the way to 5400 with the injectors appearing to be static and based on calcs are static at ~3650 RPM upwards. Yet the AFR based on my WB reading were in the 12.8 AFR arena. I increased the AFR across the boards on the dyno, but the injectors would only add fuel in the <3650 range. It picked up ~36ft-lbs on a 2% increase in fuel. But the upper RPM range remained unchanged. This is a clear indication the injectors were flowing 100% of the allowable fuel at that pressure. I have since increased my FP to allow more fuel per time to flow. Ultimately giving the injectors a larger appearance and allowing then to come down to a Duty cycle of about 81% at 5375 RPM. WIth my WB now and the new injector constant along with the different pressure it showing an AFR of ~11.8-12.2, so chances are I will have to remove PW to make the mixture leaner, ultimately reducing the PW, and consequently the duty cycle.

L8r

GofasterFirebird

iTrader: (3)

OK, I'll just believe you because your car is fast.

Hey, could you quickly comment on your timing curve? Such as max timing and what it does at WOT from 2500 rpms up? Thanks

ski_dwn_it

As I said before.....my setups runs on some wicked blended up fuel and that allows me to run much more timing than you typically would want to run. I think because of the slower/longer burn time, the timing needs to start sooner than normal for best performance. I have my total timing up to the max at WOT 41*. Some have are quick to critize my timing, but playing with it at the track, anything less yields ~6mph less trap speeds.

So I use what delievers results, and I think you should too. Use what timing the engine runs its best at, without the obvious detonation.

Typically you want your max timing coming in at or very close to your TC stall. That is what works best for me at the track. I do have a few extra degrees added as it climbs, but for the most part its 98% there instantly.

And you don't have to take any of suggestions, because I am fast. I am just like you and everyone here....trying to get the best we can with what we have available.

You will do well with your car. There are not too many street cars that run in the 11s and even fewer that are in the 10s.

That is the beauty of a setup like mine, and I can't believe that more do not copy it. You can drive around all day, as I do many days with the same luxuries and tameness of the stock configured car, but when you get agressive, look out!

My Dad drive my car last night, he has a stock vette and he said he can't believe how smooth the car is, drives as easy as his stocker, but comes alive like an awoken pissed off giant.

You would have to drive it to appreciate it.

With some tuning and some tweaking I'm sure you will be in the same boat. They are by far the best bang for the buck of any engine I have driven. Its only 23 cubes more than a 383, but I have never driven a 383 that pulls like this thing....not even close.

Streetiron85

I wouldn't have guessed that you could get that kind of fuel economy out of a big inch motor. Are other guys with 400s doing that too?
I might have to get one.

ski_dwn_it

I know that my digi dashes calculation is screwed up when I change the inj constant in the car. So I can't go by the dash MPG anymore.

But I don't think you guys have the auto calculations in your cars????

THe only way to do it is at the pump with drove X amount of miles divided by the gallons to again be full.

I never do that, as I don't really want to know how much cash I am burning away. LOL. As I said. 1 1/4 mile run uses 1+ gal of fuel

11SEC91Z

iTrader: (4)

Hey Ski you can drive my car anytime bro lol 406s and 383s are different animals for sure. but a 383 can run with a 406(if not be stronger) if the combo is correct..
Gofaster: glad you got that thing running bro..i know your excited..it will for sure be a 11 second car..and Ski is right! break it in like you want it to run...hard!.maybe like ya stole it..lol..good luck man!

BuckeyeROC

GoFaster, bring that car back home, I want a ride. And we can race 'em while I still have a chance.

GofasterFirebird

iTrader: (3)

Well, it really isn't fast yet. Soon.

MikeH

iTrader: (10)

Scott, I had around 11.3 in my 406 and the thing would not take more than 20* of timing at wot, Using 93 octane. This killed power using pump gas. I had some other problems going on, but thats to much for pump gas even with aluminum heads based on my setup. I thought my heads were 64 cc but after tearing the motor down and ccing them they were 62cc. so 11.1 turned out to be 11.3-11.4.

Try to get it at least under 10.8 to run full timing on pump 93. 10.1-10.5 would be the best range IMO.

I know others say they have run more compression on pump gas. But I will never do it again. I want to be able to enjoy the car everyday on the street not baby it. Race gas isnt cheap.

1bad91Z

iTrader: (1)

See above post. Told ya so, Scott !

Scott_92RS

I recently sold my heads and bought a set of Pro Topline 200cc Aluminum's w/ 72cc chambers. I should be down around 10.0-10.5 now, which I feel MUCH more comfortable with

PaveTim

What do you guys mean when you say your injectors are static?

87_TA

Keep Tuning,
You will love that LT1 intake on the street lost of hp with out too much torque= lots of hook on the street with a good tire.
My car with et streets is darn near as fast on street as track.

Good job.

GofasterFirebird

iTrader: (3)

Wow, this is a pretty old post.

Anyhow, static injectors are when the injectors are open for 100 percent of their duty cycle, something to avoid. Due to many other posts debating this, I am not going to define this further.

87_Ta thanks for the kind words, hopefully this winter I can get some longtubes and my nitrous kit installed.