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Aftermarket/bigger throttle bodies

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Old 04-13-2009, 05:34 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by c32AMG-DTM
It's been posted by knowledgeable sources on MBWorld that the stock C32 TB is 74mm. Are you guys 100% that the stock SRT-6 TB is only 68mm? I would've thought they'd be the same.

Incidentally, the stock E55K TB is 74mm - they've seen nice gains jumping to an 80mm AMG TB out of an SL55 for years; now there's a new 82mm TB being discussed over on MBWorld, although IIRC it's still in the testing phase.
So your saying the e55 amg supercharged t/b is 74mm stock and sl55 amg supercharged t/b is 80mm stock?
 
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Old 04-13-2009, 05:51 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by waldig
.

Bigger TB will aid inlet airflow, but not NEAR as much as this simple dual filter design. Woody
If 2 intake tubes/filters come down to a 74mm t/b how are they flowing more air than the smallest point whcih is the 74mm t/b? Mrphotoman graciously pointed this out to me a while back and i cant really argue with it.
 
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Old 04-13-2009, 06:16 PM
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Talking Re: Aftermarket/bigger throttle bodies

All restrictions are additive, and the 74 is 74, adding more infront is not helpful, I showed the dyno effect of doubling the intake pipes to 2. Woody
 
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Old 04-13-2009, 07:11 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by 240M3SRT
If 2 intake tubes/filters come down to a 74mm t/b how are they flowing more air than the smallest point whcih is the 74mm t/b? Mrphotoman graciously pointed this out to me a while back and i cant really argue with it.
Science

Proper air/fuel ratio is what produces maximum HP... The Bosch ECU tries hard to maintain a set air/fuel ratio by monitoring the O2 sensors and adjusting the amount fuel delivered to the cylinders. Introduce more air and the ECU will attempt to deliver more fuel to maintain the AFR. (with a proper tune of course)

A larger filter area (and..or... a less restrictive filter) will make it easier for the air to flow.. No big news here...

To allow more air (or fluid) to flow through, or over, a certain passage; Bernoulli's Principle is used in the design to create a pressure differential. (dynamic)

Bernoulli's Principle is what makes the wings of an airplane (or bird) fly by creating lift - yet alter the angle of attack and it will change the dynamic pressure differential - or stall. (not to be confused with the engine)

Bernoulli's Principle is what makes pumps and siphons push more fluid through their openings, then say natural pressure. (static)

Bernoulli's Principle is used in carburetors. The great California Aqueduct and the Los Angeles river both depend on this principle.

The Supercharger in our car uses a form of Bernoulli's Principle as does the "V" shape you see designed into the the "Y" pipe prior to the throttle body. (A "T" junction, like one found in a PVC connector will not).

The limiting factors in our case are the amount of fuel that can be delivered, the amount of compressed gas that can pass thru the valves in the time frame that they are opened, and the amount of compressed gas our cylinders can hold.

The air passage(s) used prior to our Supercharger uses both static and dynamic air flow. After the Supercharger, it's all about compressed air pressure (or PSI).
 
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Old 04-13-2009, 07:38 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by waldig
All restrictions are additive, and the 74 is 74, adding more infront is not helpful, I showed the dyno effect of doubling the intake pipes to 2. Woody
Yet IF the intake system's intake restriction has been properly addressed, eventually the TB should become the weak point, correct?

I'm not sure how your dyno charts illustrate the efficacy of a larger TB for the M112K - isn't it more about measuring intake vacuum, where "less" is "more"?

While it would be a fair amount of work, it'd be interesting to see NW single CAI w/ 74mm TB, NW double CAI w/ 74mm TB, NW single CAI w/ 80mm TB, and NW Double CAI w/ 80mm TB - the first would likely be the worst, the last likely the best, but the two middle scenarios... who knows?
 
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Old 04-13-2009, 07:41 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by 240M3SRT
So your saying the e55 amg supercharged t/b is 74mm stock and sl55 amg supercharged t/b is 80mm stock?
Yes, I believe the E55 TB to be 74mm stock - that's the whole premise behind why those guys spend the big bucks to upgrade to 80+mm when looking for max power/torque.

Some of the high-end 55 AMG's had 80mm TBs; maybe it was euro-spec, or an optional upgrade... I don't recall offhand. I do know that some SL55's had 'em, but not all - there are threads on MBW in the w211 E55 section that list the specific part #'s needed for the 80mm TB conversion; if you're looking to do this, they'd be a good resource.
 
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Old 04-13-2009, 08:07 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by c32AMG-DTM
Yes, I believe the E55 TB to be 74mm stock - that's the whole premise behind why those guys spend the big bucks to upgrade to 80+mm when looking for max power/torque.

Some of the high-end 55 AMG's had 80mm TBs; maybe it was euro-spec, or an optional upgrade... I don't recall offhand. I do know that some SL55's had 'em, but not all - there are threads on MBW in the w211 E55 section that list the specific part #'s needed for the 80mm TB conversion; if you're looking to do this, they'd be a good resource.
The first few years of the SL55's had the 74mm TB and made 496bhp..............then M-B upgraded in 07(I believe) to 80mm TB and it jumped to 517bhp.
 
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Old 04-13-2009, 08:18 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by Moparrbust
The first few years of the SL55's had the 74mm TB and made 496bhp..............then M-B upgraded in 07(I believe) to 80mm TB and it jumped to 517bhp.
Thanks!

 
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Old 04-14-2009, 05:26 PM
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Default Re: Aftermarket/bigger throttle bodies

Does anyone have the MB or Bosch part number for the 74 mm TB that fits the M112 NA engine?
PM info.....Thanks
 
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Old 04-15-2009, 02:39 PM
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Default Re: Aftermarket/bigger throttle bodies

Guys, i measured the stock srt-6 t/b. Its 74mm id and 80mm od.

I have an n/a one on the way, it is supposed to be the same, ill post results.
 
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Old 04-15-2009, 11:47 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by Moparrbust
The first few years of the SL55's had the 74mm TB and made 496bhp..............then M-B upgraded in 07(I believe) to 80mm TB and it jumped to 517bhp.
The first SL55 Production year 2002 had the 80mm TB without a Bypass in the IC. In 2003 they changed it to the Bypass System with a 74mm TB, mainly because of lower fuel consumption. The new SL55 07/08 with 517bhp again uses a 80mm TB.
 
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Old 04-16-2009, 07:48 AM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by SLK32Germany
The first SL55 Production year 2002 had the 80mm TB without a Bypass in the IC. In 2003 they changed it to the Bypass System with a 74mm TB, mainly because of lower fuel consumption. The new SL55 07/08 with 517bhp again uses a 80mm TB.
So the question is where to find one for a reasonable price. And are we certain they are measuring id? Internet info can be uncertain sometime.
 
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Old 04-16-2009, 10:34 AM
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Default Re: Aftermarket/bigger throttle bodies

Its not worth the high price in my opinion and from what I know ,the SL55 TB does not fit the 32- Engine...
 
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Old 12-29-2010, 10:43 PM
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Default Re: Aftermarket/bigger throttle bodies

Bringing this old thread back from the dead.

I thought I was done modifying the car but you know how it goes so now I am trying to make a plan for this years modifications. Has anyone used Maxbore for their TB? Anyone have any results from boring out their TB to 76mm?

Does anyone have the Part # handy for the SRT6 TB?
 

Last edited by SRT6_Roadster; 12-29-2010 at 10:45 PM.
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Old 08-13-2016, 06:05 PM
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Default Re: Aftermarket/bigger throttle bodies

OK, I cant seem to find a definitate answer.

Is there any bolt on upgrades as far as a throttle body goes for a slk32 amg, maybe from a sl55amg or another mercedes model etc?

From what i read the stock size is 74mm on a slk32 amg, but there was some talk about 78/80/82mm possibilities.

Is anyone running a larger throttle body on their srt-6 or slk32? what are the options, or boring only?
 

Last edited by performanceisland; 08-13-2016 at 06:09 PM.
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Old 08-13-2016, 06:09 PM
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Default Re: Aftermarket/bigger throttle bodies

Woody ( waldig ) has a dual 74 mm setup working ( 148 mm total, big enough for you ? )

https://www.crossfireforum.org/forum...g-my-srt6.html
 
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Old 08-14-2016, 04:23 AM
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Default Re: Aftermarket/bigger throttle bodies

See attached my collection of notes.
The 82mm is the most common, but I decided the extra 4-6bhp wasnt worth it.
 
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Old 08-14-2016, 09:13 AM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by Billy22Bob
See attached my collection of notes.
The 82mm is the most common, but I decided the extra 4-6bhp wasnt worth it.
that's a lot of info to sift through, i think id be fine with either a 80mm or 82mm throttle body, i just want to see which one is the most plug and play. And which sizes require the supercharger inlet to be swapped.

i'm trying to increase the air flow between the supercharger and the engine, i want to upgrade the intake manifolds, lower y-pipe, I already have the sl55 amg intake, and upper y-pipe, which will need to be replaced again from what i am reading if i go with the larger sizes of throttle body, and last the supercharger inlet. Now i have to read and see what part numbers i need.
 
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Old 08-14-2016, 03:27 PM
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Default Re: Aftermarket/bigger throttle bodies

Originally Posted by 240M3SRT
Just getting back to the forums, will try to cover all issues in this thread.

74mm is almost 3" and 80mm is just above 3". Thats 6mm gain for $$$$. And thats not gonna be 20hp imo. Now add an additional t/b and we are talking way more air comming in. But the only sensors we have monitoring air flow is MAP and temp so how will it know any difference co nsidering that the i/c outlet is the same size(where the sensors are located). So when would the benefit come in? When your running larger y-pipe and manifolds. As far as making it fit on the blower inlet hat and making a custom intake leave that part to me.

If i can get confirmation that an n/a tb is the same i may buy one and try it. But id be suprised if it were.

And on top of that id still like to know if the drive by wire will be ok if i splice the harness. In other words my is there enough power to turn the valve on 2 t/b's will no ill effects. I dont believe the t/b in any way acts as a sensor so i dont think the ecu will know any difference. Electronics has never been my forte, building the hardware i can handle.

While I admire your efforts to provide better breathing for the Crossfire, it is only 195 cu. in., without changing compression ratios you can only get so much air in. without dieseling. I would think that our biggest obstacle to free breathing is in the exhaust system.
 
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Old 08-14-2016, 06:14 PM
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Talking Re: Aftermarket/bigger throttle bodies

I installed dual throttle bodies and ran them in parallel, but the tuning was a ***** and it did not run well, too much air and it the computer does not like it and will not accomidate the faster infusion of air, throttle. Woody
 

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