stranges12712

iTrader: (1)

I dont know if this has been discussed here, I could not find anything on it. But since im upgrading the 1.6L intake manifold to the begi, can you change your throttle body? Has anyone ever upgraded theres to a bigger one for more air flow? I havent really seen any except for on ebay...Braineack i know you did your own intake manifold did you upgrade your throttle body, is there a bigger one out there for the 1.6 that works? Thanks, Mike.

dustinb

If you're running a full standalone ECU, you can essentially run any throttlebody you want. I think the BEGI ones can be used with a Ford Mustang TB.

stranges12712

iTrader: (1)

What year 2005+ from the 4.6L? Or what would you say to something like this...80MM THROTTLE BODY UNIVERSAL MAZDA MIATA MX-5 RX7 RX8 : eBay Motors (item 270484870851 end time Feb-11-10 17:39:31 PST)

dustinb

I'd probably contact BEGI and ask them what ones will work. You have to make sure the bolt pattern is the same.

Braineack

iTrader: (62)

dont use a mustang TB. Look at Honda or Nissan ones. A honda B series is 10mm larger than our and can be found for $10 with TPS and Idle valves included.

Jeff_Ciesielski

iTrader: (10)

VQ throttle body FTMFW. You can find them for 50ish bucks on ebay with tps attached. IIRC its the biggest OE throttle body produced.

johnmatt

iTrader: (8)

But if you go TOO big aren't you kindof hurting yourself?

dustinb

I was wondering the same thing. If your charge pipes are only 2.5" (63.5mm), then why go any larger then that?

Jeff_Ciesielski

iTrader: (10)

I don't see how (*waits for the engineer smackdown*). The way I see it in a turbocharged application, any restriction that you can remove from the charge pipes is an improvement. The only criticism I've ever heard is that that large of a TB is like an ON/OFF switch, and I can tell you from personal experience that that just isn't the case. The car I drove had excellent street manners with an aftermarket IM and a VQ throttle body.

EDIT: I'd like to point out that I was mistaken. The car I drove had a VH45 throttle body, not a VQ35 throttle body ( damn nissan with their V's Q's and G's )

dustinb

It's my understanding that by going to large in your charge pipes and intercooler that you experience pressure drop and can actually lose power.

Jeff_Ciesielski

iTrader: (10)

I stand partially corrected.
In a small turbo/lower boost scenario, if you go *TOO* big, you can lose power, However once you start flowing more air from the turbo than the given TB can support it becomes worth it

--STOLEN FROM VWVORTEX--
HORSEPOWER / correctedhp
BOOST : Wastegate pressure - 17PSI
80mm: = 388.9 hp @ 7300 rpm
75mm: = 390 hp @ ?
70mm: = 383 hp @ 7200 rpm
65mm: = 378 hp @ 6500 rpm
60mm: = 374 hp @ 6700 rpm

BOOST - 22SI
80mm: = 451 @ 6700 rpm
75mm: = 447 hp @ ?
70mm: = 447 hp @ 6700 rpm
65mm: = 430 hp @ 6800 rpm
60mm: = 439 hp @ 6800 rpm
STOCK AWP Manifold + 60mm: = 421 hp @ 7100 rpm


TORQUE / lb-ft
BOOST : Wastegate pressure - 17PSI
80mm: = 322 lb-ft @ 5600 rpm
75mm: = 333 lb-ft @ ?
70mm: = 318 lb-ft @ 5600 rpm
65mm: = 320 lb-ft @ 5800 rpm
60mm: = 312 lb-ft @ 5700 rpm

BOOST - 22SI
80mm: = 380 lb-ft @ 5500 rpm
75mm: = 382 lb-ft @ ?
70mm: = 374 lb-ft @ 5600 rpm
65mm: = 369 lb-ft @ 5600 rpm
60mm: = 371 lb-ft @ 5600 rpm
STOCK AWP Manifold + 60mm: = 365 lb-ft @ 5100 rpm
--END HIJACKED CONTENT--

The question is, where is that happy medium for the miata? I think Brain is most likely right with the Honda B-Series TB. 10mm over stock would probably see reasonable gains (esp. for the price) without being too big and causing torque loss due to lower pressure.

johnmatt

iTrader: (8)

What size is the stock TB anyways?

Jeff_Ciesielski

iTrader: (10)

On a 1.6 I believe it is ~60mm.

gospeed81

iTrader: (51)

I thought it was 52mm, but have yet to whip out the calipers...should have done it last night.

Jeff_Ciesielski

iTrader: (10)

Really? It is 2.5" OD roughly. Is the casting that thick that it loses .5"? Damn.

Braineack

iTrader: (62)

it's 52mm on all motors, you give mazda way too much credit.

na8psi

iTrader: (1)

[threadjack]

Is porting the stock TB not an option for anybody? What TB is the easiest to try and make compatible with our intake's and TPS? Im currently looking into having someone make me a manifold, (1.8, any takers?) and I was curious about TB size, I currently have 2.5" charge piping and believe about a 60mm or maybe even 65 would be in order to see some power gains? Any real substantial evidence out here to support the "larger TB bore=more power" notion for these cars?

Again this question is about 1.8s

[/threadjack]

Braineack

iTrader: (62)

you could send your TB to maxbore.com