I know that there aren't any aftermarket throttle bodies out there. But can something else be done?

How bout boring out the stock throttle body?

Are there universal big bore throttle bodies out there that woudl could use, even with small modification?

If anything like this is done would there be any problems?



Juker008

 

actually useph_murray is looking into that already in another thread, there aren't any throttle bodies out there right now, and in addition our throttle body is quite large to begin with, i believe it's a 64mm bore.

just keep checking on the other thread...

http://www.acura-cl.com/forums/showt...threadid=90825

 

Useph_Murray here, You have to get an universal throttle body. I was telling slyraskal that they do not make primary parts for the cl because they consider cl as more a luxury car. I have to find out the info and the brand I have on my car. I will get back to you when I get the info.

 

There are quite a few places that will bore our stock one out and put a new butterfly valve in there.

 

With all that trouble and expense, is it worth the difference in perfomance you would get?

 

well, in our car's since there haven't been any parts that were designed specifically for our car it's hard to say. BUt it's been proven in other cars, integra's and civic's that doing this greatly improves performance but other things along with the throttle body help this like intake manifold & fuel rail.

the throttle bodies in our cars are already quite large, but i'm guessing improving this would help, now only if we could get them specifially made for our cars along with an improved intake manifold then we'd be seeing some great performance increases.

 

Plz explain how a fuel rail will inprove performance. I understand that it will supply additioal fuel "when needed" but without additional bolt-ons I can't see how a fuel rail will improve performance.




Juker008

 

Well, I feel much improvement in the performance. I have alot of weight in my trunk. My car was driving like I had two fat people in the back seat. When I got that horse power, it was perfect.

 

This is where a better intake manifold with the addition of a fuel rail and throttle body can improve performance, that's why i said it's all of these combined that help greatly. From what i've heard, basically more fuel get's delivered to the combustion chamber, along with more air since the intake manifold was upgraded which in turn allows for a larger and cleaner burn turning into more hp.

this is what i've heard from shops and read in articles about other cars like integra's and civic's. before my integra was murdered by a hit and run driver, i had my next upgrade set to upgrade the throttle body and intake manifold because that greatly increased the output of the engine.

if you want some reference material on throttle bodies, go to http://www.edelbrock.com/

 

useph,
Any update on which TB your car has?

 

No, give me a couple of days. I keep you posted on the info. I see you live outside of philly. Where are you?

 

I live in the burbs in montgomery country. I work in Villanova. Where in Philly are you at?

Excellent, we'll be awaiting your response!

 

Ok, I live in North Philly and Ardmore in Montgomery County, right behind the Acura dealership. Did you get your car from Ardmore Acura, I did. also, I just got off the phone with my mechanic. He said that he cannot remember, but he will find out. I told I have people wainting for the answer. So just give me a couple of days because he is busy.

 

Ah cripes you are right near me. I bought my first CLS there. We should meet up i'd love to take a look at the hardware.......

 

LOL, No problem. I am down Virginia right now on a little vacation. I will be back home Sunday. I am a student at Temple University, and classes starts up next week so I will be home. Then we can meet up somewhere. You might saw me. I have the Sundance Gold color CL-S with the 18 inch rims. That Special Edition CL-S that came out in 2001. There was only 200 colors release in the U.S.

 

Ah cool. Nice yeah let me know whenn you get back in and settled and we can meet up.

 

In a car that the throttle body is restrictive, then yes. If ours is really 64mm, then I doubt you'd see anything. Most vehicles built today have a decent sized throttle body. Unless you're doing major engine work to make her breath way over stock, it's kind of a waste of money.

Not sure about boost though. In my mind, a turbo or supercharger doesn't count, since it'll force the cylinders full (Unlike natural aspiration where the intake and throttle body can be restrictive). :P

 

Boring out the TB without porting the intake-manifold (or at least EXTRUDE-HONING it) won't make too much of a difference. I think on these cars the car controls timing pretty well (at least based on the stock maps). However... there is some playing-room with the fuel-pressure. There is about a 5-6 whp difference between Headers, Intake, Exhaust and no fuel-tuning vs. the same mods and some fuel-tuning.

 

The only time a fuel rail swap can assist in making power is if the stock one is too small to supply enough fuel at WOT demands. We are far from this at this time.

As for the throttle body, there is little to be gained. The inlet is upwards of 67mm which might trim down a little at the throttle plate (had my Mititoyo mic on it). But regardless, the size is more than enough for our engine; below is a little math to give ya an idea:

Our engine is about 196CI (3.2 liters) and to be generous I'll use an Ev (Volumetric Efficiency) of 90%. This would calculate out to 357 CFM

For throttle bodies you what to keep your flow rate below 300 Feet/Min but not too terribly low or else you get drivability problems. So 357 CFM converted to Feet/Min through a 2.52 Inch TB is 172 Feet/Min. This is well below the threshold.

More needs to be done to the car before a larger TB is needed. Maybe with the blower it might be reasonable but that still only puts the flow rate at 240 Feet/Min.

 

I'm still out on the intake manifold polishing. I do feel it may provide benefit but not yet. I'm going to re-test my car on another dyno with a different intake to be sure.

Before:


After:

 

OK Big Guys (that means u Scalbert & u allmotor_200),


Now lets take a CLS that has CAI, Headers, full Cat Back Exhaust, P&P, Extrude Honed, AND a five angle valve job, (3 angles on the intake and exhaust and two on the valves) . If I do go for a 5 angle valve job I am definatly upgrading to SS valves.

So with all that then would u feel that a bored out TB would be in order? If so what would u think would be the gain?


Also if all that were done would the fuel rail need to also be on order? How bout a FPR? If a FPR is needed where in this line up do u think that it would go?


Tnx




Juker008

 

and then you're gonna put 400 lbs of stereo in the trunk ?

 

The more i see. The more I begin to believe that the flow in the engine is pretty good. What is causing turbulance in our engine is the butterfly valve in the second intake runner. That second intake runner is the second to last major impediment before the air gets into the combustion chamber. Of course the last thing is the lip of the intake port and the valve but until somebdoy takes some serious equipment into the engine to see how the flow is actually moving into the combusition chamber. Sure we could get 3 angle, 5 angle jobs done but we have not clue if it'll help at all. Heh......for this i think we have no recourse.

 

Adding these things simply increases the Ev, which is good but not something that will nessesarily require a larger TB. Even with an Ev of 100% that is still only 397 CFM or close to 195 Feet/Min.

Could a larger TB be used and gain some power with all of the mods done, yes but don't expect much. Going to 68mm would be more than enough but yield only a few HP.

Having removed the fuel rail I would guess that it is good enough to support 500 HP, no way you would hit that power mark with those mods.

 

Not actually, the butterfly valve just seperates the percieved volume appearent to each bank, I doubt there is serious flow through there being used by each runner.

Assembly Drawing

As shown, air flows into each front and rear chamber and then into the runners. There is no reason that air flow is impeded through the IMRC plates and passages. In fact they are quite a bit larger than the runners.

 

It's threads like this that make me feel like an absolute retard.
Somehow I still love reading them though.
Thanks guys.

 

I disagree. That's why acura went with a rotary design for the ivtec engines.

 

Rotary design??

Are you refering to a rotary valve for the variable intake manifold??

 

Yes, by the second intake runner.

 

Ah, I see. But what is missed is that we have a variable volume intake manifold whereas the one you are referring to has variable length runners. They are both multi-stage intake manifolds but use different concepts and different designs.

A variable length manifold or variable length runner system has valves which switch between long runners for low RPM operation, to short runners in high RPM operation.

Ours have fixed length runners but the apparent volume for both changes when the valve opens. Now that both chambers are connected; the varying pulses creates the inertial charge condition (the supercharging effect).

Two different methods to allow better torque through the RPM band, but certainly different.

 

I agree with everything you said. I was only speaking in terms of turbulance. It's the only point that anybody here can speak to with any degree of confidence.