I am stock now, save for intake and exhaust. I've purchased an extra Eaton that I planned on porting myself, however after a thorough inspection of the inlet I've decided to send it to Stiegemier. Until I can save up for the port and supporting mods I thought that as a machinist, it would be a simple thing to make a pulley as well as a pulley puller, and enjoy a couple of extra FREE ponies until I can aquire the goods. Am I an idiot for not doing this sooner, and again FOR FREE, or should I have some concerns? Any anput would be greatly appreciated. Oh yeah, my stock pulley measures 3.555 instead of the advertised 3.65. Thats almost a hundred, which in my line of work is HUGE...
Tune required for 3.2 pulley on Eaton?
- Thread starter Jocko
- Start date
Yes, you will most likely need a computer adjustment with the addition of a 3.2 pulley on your Eaton. Many folks have run 3.10, myself included, and a tune was necessary, not only for safety, but also to maximize the benfits of the extra boost that is achieved.
This is getting a little better. As far as not doing much anyway, It's free, and still being "slow", I'm desperate. When I put that FIPK on there, man I thought THAT was the Nuts. I just thought that perhaps there might be some brave pioneers from the olden days of '03 Cobra lore that at one time held in their hand a new-fangled "tiny" 3.2 pulley and said "Damn the torpedoes, I'm slappin' this badboy on!" and that I might benifit from their experience and results. I might also point out that as it frequently happens on this website on Friday nights that I, not unlike many of you, have had some beers so I apologise in advance for subjecting you good people to any of my BS.
Incorrect information. DEFINITELY need a tune with the addition of a 2.93 upper pulley. And secondly, a 3.20 pulley will give you an extra 2+ lbs of boost over stock which will certainly be noticeable. I had a 3.10 upper installed on my Cobra in September, 02 and dynoed at 441 RWHP with Magnaflow and CAI.DOHC said:
Go with a smaller pulley since you have to tune it anyways....
According to Cobrabob's estimated peak boost a 3.2 pully would net almost 3 pounds of boost over stock, but I agree that even 2 pounds would definitely be significant. I was just hoping I might get by in the meantime with the pulley without having to incur the expense of tuning, supporting mods, etc. just yet. Thank you for the replies.
By the way, Ironterp, you truely ARE a pioneer. Sept. '02? I was drooling over the 03's at the Texas State Fair in the car building, never dreaming I might own my dreamcar someday, and you were "living the dream". Congrats.
That is definitely incorrect information. No way can you run a 2.93 without a retune. Well, you could, but it's an engine disaster waiting to happen. What Iron Terp said is spot on. NEVER do it if you value your engine.DOHC said:
Jocko, that chart is generic and should only be used as a guide. It does not take into account the varying combinations of intake and exhaust. To really do it right , every combination listed would have to be with the exact same intake/exhaust mods, on the same car on the same day. So it is only a guide. I know for a fact that actual numbers reported by people here can be as much as 2 lbs. different from that chart.Jocko said:
I have to update my FAQ page and will make a note to this affect so that people use it only as a general comparison guide. ;-)
CobraBob-
Yes, I definitely regard the chart as more of a rule-of-thumb, and have no doubt people will realize variations in boost levels due to any number of variables. I would just like to say thank you for compiling such an incredibly extensive amount of information on the subject! To the uninitiated and the shade-tree mechanics like myself, or ANYONE for that matter it has proven to be an invaluable reasource. Not to get too off topic, in your experience have you found such a wide variation in stock pulley sizes, 3.65 - 3.55, or is my measuring the pulley itself sans-belt and not the pulley with the belt ON to account for such a difference? There seems to be a pretty good fluctution in stock dyno results and I wonder if pullry size variations could contribute. THANKS AGAIN!
Mike
Yes, I definitely regard the chart as more of a rule-of-thumb, and have no doubt people will realize variations in boost levels due to any number of variables. I would just like to say thank you for compiling such an incredibly extensive amount of information on the subject! To the uninitiated and the shade-tree mechanics like myself, or ANYONE for that matter it has proven to be an invaluable reasource. Not to get too off topic, in your experience have you found such a wide variation in stock pulley sizes, 3.65 - 3.55, or is my measuring the pulley itself sans-belt and not the pulley with the belt ON to account for such a difference? There seems to be a pretty good fluctution in stock dyno results and I wonder if pullry size variations could contribute. THANKS AGAIN!
Mike
I started out with my first pulley mod, using a Billetflow 3.40
pulley. My tuner said once it was on you definitely need a
tune. So I did and I've gone to a 293/4 # setup now.
pulley. My tuner said once it was on you definitely need a
tune. So I did and I've gone to a 293/4 # setup now.
Mike, I believe all 18,000+ 03/04' Terminators came with the identically machined 3.65" upper blower pulley. Your variation could just be how it was measured.
You could be right. The pulley I measured was purported to be stock (I don't have it handy) and it had a # 3002 095 (or similar-can't remember) followed by the letters E&C. I measured it 3 times
nce on calipers, calibrated micrometers and once again on a Smartscope when I was taking other dimensions. Just to verify, with a little difficulty I went out back a moment ago and removed my belt to access the pulley to measure the one on my car (with calipers)which I am reasonably certain is stock and here's the thing... 3.55 +or- .005. I bought the car used and the upper bracket to the pulley guard was broken, I'm not sure if this is a common issue, so i'm not 100% certain it is completely unmolested. I measured the outside diameter of the "lands" or the upper most points on the grooves.
nce on calipers, calibrated micrometers and once again on a Smartscope when I was taking other dimensions. Just to verify, with a little difficulty I went out back a moment ago and removed my belt to access the pulley to measure the one on my car (with calipers)which I am reasonably certain is stock and here's the thing... 3.55 +or- .005. I bought the car used and the upper bracket to the pulley guard was broken, I'm not sure if this is a common issue, so i'm not 100% certain it is completely unmolested. I measured the outside diameter of the "lands" or the upper most points on the grooves.I didn't say all car's needed a tune... Me and others have run several different test on our cars. A tune is allways good, put sometimes not necessary. Some guys on this site will have you thinking that you need a tune with a stock K&N air filter replacement. 2 cars have been run with 2.9s(stock fuel system and air box) befor tune. Its been 2 years but I think A/F was in the low 11's. All I was gitting at was if the guy was short on $ It will work untill he can git a tune.
I have to agree Dwight. I have never heard of a difference sized upper done from the factory. I have to believe it is simply the way it is being measured, or the tool is slightly off.IronTerp said:
You would risk a very expensive motor because your gut feeling is that it doesn't need a tune?DOHC said:
Guy, you have to at least have the A/F ratio checked with a wideband or local tuner.
CobraBob knows these motors inside and out. Also, kudos to Iron Terp.
Jeff
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Assuming the motor doesn't grenade before you have a chance to look at them.DOHC said:The plugs tell the story
Somehow that doesn't seem to make good sense.
Jeff
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