ModAddict

Well then,....I wonder if the stock crankshaft pulley is smaller on the TL-S/CL-S,....or maybe they just have a less restrictive intake/exhaust systems. I'm also suprised that opening up your intake increased your boost. I am waiting on stone headers so my exhaust is stock, and I run 1/2 psi more than the other CL-S S/C cars. I figured that was due to a more restrictive exhaust and expect to be down 1/2# when the headers go on.

Doom878

Will this piggyback coming out only apply to s/c'ed cars?

MtBikR

This particular piggy back for the ECU that is being discussed is only practical for forced induction vehicles as its main purpose is to work with the ECU to hide the boost in the air intake and allow the use of higher levels of pressure i.e. differnt pulley for S/C or larger boost settings for a turbo. without the ecu backing off the timing due to ping detection. But I am sure other chips or ecu modifications will become availible for non f.i. cars soon. You can already use some of the complete management systems out there like AEMs to completely control the cpu.

Doom878

I don't think the AEM EMS is usable for our car. I know of no Accords with any because it's not available for our car. I think it was something to do with the transmission points feature that AEM couldn't figure out.

mattg

it will work. nobody has wanted to fork over $1200, plus how ever much it would cost to dyno tune the car. for our application, all of the programming would have to be done from scratch.

typeR

im pretty sure you wrong about the UR pulley it under drives both power steering and the ALT.

tool462

typeR- call UR yourself, they have a NEW crank pulley for s/c applications for the Cl and Accord only. Stock diameter and lightened, stock dia running the alt (also running blower), underdriven PS.

sonor kid

Tool is right, as the I have his original UR pulley set. He took them off when he put the supercharger in, so I installed them on my CL.
UR recently came out with just a new crank pulley only, which is for supercharged applications. It is much lighter but remains at stock diameter.
I believe Comptech has the high boost pulley Tool is using but they don't sell it with their kits. If installed, Comptech will not warranty the blower.

ModAddict

Allright, I was at the dyno this am, and at the request of Scalbert, I pulled with, and w/o, the IMRC. Something happened I did not expect. With the IMRC off, the boost peaked at 7.5 psi! With the IMRC on I was just a smidge over 6.5 psi.

types1967

ok pulled my imrc plug and went for a drive was on the cell with mod addict and i noticed i was pulling steady boost at5psi!!!! where with the imrc plugged in i was at 4.5psi.this is very interesting.

typeR

no need to call if you say it i believe you...i hadnt heard about the new UR pulley ..sorry

Ogolden1

I don't understand WHY it has to be the alternator pulley! - it is a total BITCH to get to and requires the removal of the blower unit.
Why not have a smaller pulley for the blower??? - it would be sooo fast and easy to change!

ModAddict

You do not need to remove the blower to change it. Remove the belts. Remove five bolts; two on the alternator, one thru the CT alternator bracket into the block, and two thru the jack screw bracket into the CT alternator bracket. Turn the altrnator so the pulley is facing up, and attach a 10-12" extension on the impact wrench and a 22mm socket, and off it comes. It's about a 30 minute job after a few times.

With your low octane gas out west, you'll need some help before you can bump up the boost. :P

Doom878

I checked AEM's site and it says manual transmission only. Where did you find out it was available for Accords with autos?

ModAddict

There's an outfit in the Detroit area called Payne Tech. They are an AEM EMS factory consultant. They have a tuner there that will pioneer set-ups for the AEM EMS. The just finished their own NSX with drive by wire, which until that point had never been done, and from some point in the near future, it will be available. He said the TL-S would be easy compared to the drive by wire NSX. Will it be able to manipulate the shift points? Maybe not, but that's not really what I'm after anyways. All they need is someone willing to buck up to do it the first time, and the rest will be easy.

Doom878

Nice. An Accord with a Unichip was putting out 200whp with i/h/e and chip. Unfortunately they didn't produce the chip and he had the prototype so maybe this is another way to achieve that.

Doom878

Okay I've checked google, yellowpages.com, and AEM's dealers and I can't find contact info for Payne Tech. Anyone have a site or phone?

ModAddict

Sorry, no "e" at the end.

http://www.payntechnologies.com/index.html

I think they're going to need your car a while for the first one.

Doom878

We gotta couple s/c Accords in the midwest area so maybe they'll be pioneers. I'm a little far. Thank you for the link.

Ogolden1

What is "drive by wire"???

ModAddict

Accelerator pedal sends an electrical signal to the throttle, as compared to our mechanical cable.

scalbert

Actually you should be complaining...

Boost is caused by the resistance of flow, the blower is moving more air than the engine can move. If you increase the engine displacement the boost will drop per a given blower speed. If you increase the ability of the engine to move air the boost will also drop.

More boost is not better; less boost on a given blower flow rate is. It means the engine is able to use the additional flow from the blower better.

So by extrude honing the manifold boost increased significantly?? This is contrary to all logical thought unless it is now somehow causing a restriction in the flow path. The extrude honing should have caused slightly lower boost readings but increased power slightly. The amount it went up is also of major concern and not correct.

As for running more boost on the AV6 with its 9.4:1 CR; yes this is better. Also, the lower displacement of the AV6 allows them to turn the blower slower to generate the same boost numbers.

ModAddict

Tool462, I've heard of aftermarket cats failing and plugging up the exhaust. That could cause your higher boost numbers maybe. Try putting the stock cat back on, and see if your boost drops.

scalbert

But to answer the original question; running pump gas, 92/03 octane with the J32A2 CR of 10.5:1 the maximum boost run would be as follows:

Non-intercooled: 6 - 7 PSI
Intercooled: about 9 - 10 PSI.

civic4982

I think there's a lot of guessing going on here... where do you get these numbers? I'm supposing that the strength and melting temperature of the parts should have to do with how much combustion and power is going on in the cylinders...

running an engine to those extremes it'll find its weakest link and break it. that could be anything on the drivetrain. how're you guys guesstimating this besides pulling numbers from thin air?

(I mean no disrespect, you guys are much more engineering knowledgable tahn I am)

scalbert

I came up with the numbers by determining the absolute chamber temperature with and without intercooling. This takes into account the boost, temperature rise with a roots blower (and subsequent removal if an IC is in place) and the engine CR.

I used a somewhat standard value of 1075 degree absolute which corresponds to about a 13.0:1 CR on pump gas.

So there was some logic behind it and wasn’t all guesswork.

TopGum

Would anyone venture an engineer's guesstimate as to what my boost would be with the original UR crank pulley and the stock Comptech SC pulley? With the original UR crank and the Comptech high boost pulley?

scalbert

What is the size difference?? From that we can do the calculations to give you a very good guess.

GS Dave

I'm glad Scalbert chimed in on the increased boost after extrude honing. You should see a slight decrease in psi due to any type of porting/polishing of the intake, heads, or addition of headers. You should seriously take a look at what might be causing your boost stacking.

There was a questoin earlier about turbo boost vs roots type boost. The question was answered but did not nail home the fact that a roots type blower such as yours and mine, will generate far more heat in the intake than most turbos. As a result, you should be able to run slightly higher boost in an turbo cat than in a non intercooled blown car.

Scalbert, do you know how much boost you are going to lose(if any) with your IC?

later,
Dave

scalbert

At the lower boost levels the heat imput difference is minimal. But as the wick is turned up the turbo really starts showing its superiority.

As for pressure drop through the IC; based on all of the infomation I have found it should be less than 0.25 PSI. So very minimal.

TopGum

The UR crank is 20% underdriven and it's diameter is 141.0 mm at the alternator driven surface.

MtBikR

So is there only one person running the blower with the new UR underdriven pulley? the crank one? Any gains?

TopGum

Nobody I think. It is not a good combination... too much boost loss. I am asking if someone can help me out with the calculations as to how much boost is lost with the UR crank (which I have now)and if it can be made up for with the high boost pulley. Otherwise, UR makes a oem size crank (Ultra Sc) that is lighter than stock but it's $245 for the pleasure. The high boost pulley is $60.

scalbert

Since you know the percent underdrive that would most likely be pretty close to the boost loss. 4.0 PSI - 20% = 3.2 PSI Boost or about 10 - 15 WHP. More than what you are gaining with the pulley.

So it would be better to go with the stock or same size as stock crank pulley.

However, if you never planning on increasing the boost further than what the kit would have provided in base form then running the higher boost pulley with an end result of about 4.5 - 5 PSI boost is more cost effective.

Accord_V6_400m

iTrader: (1)

Bringing this thread back to life since it has some valuable info