4age ITB throttle body dimensions, bolt holes etc ?

[ed]

can someone confirm minimum spacing required between runners, bore dia, and bolt pattern for a pair of 4a throttles? and do they work in pairs, or only as a set of 4 linked together? how modular are they generally speaking?

thinking of trying to make a 'universal' itb manifold that you drill and finish yourself to suit different throttle bodies.

cheers
ed

[roadsailing]

I have a set of silvertop ITBs i can measure up tomorrow if nobody beats me to it if thats what you mean. They work in pairs from memory.

incidentally I asked you ages ago about mandrel press-forming bellmouths, i'm sure the PM got lost or something but i'd still like to know how you went with it.

PM me with more details, what measurements you are after etc if you want, bolt pattern will be as accurate as i can get it with Verniers, as its a bit of an odd 3 bolt arrangement. for 4AGEs nothing is really as cheap/easy as the T3 adapters unless you have a machine shop and lots of free time.

[oldcorollas]

Heya Ed,
I don't have any more to measure, but i did at one stage..

anyway, for what you are interested in, heres a couple of points.
there are two castings. one for TPS at the end, and the other three are identical.

all 4 throttles are seperate, and have adjustment between each one. one side has 2 screws to set the synchronisation, the other has a tang that goes between them.

the end throttle that is non-TPS of course doesn't have the extra stuff hanging off the shaft, since there is no adjacent throttle, but you could easily make up bits for it and bolt them on as there is a nut at the end, and a throttle stop (i think there is a stop on each throttle)

the two centre throttles basically identical (with one extra bit for the ball joint for throttle linkage iirc??)

so.. if you had a TPS throttle and either of the two centre throttles, you could make them as long as you want, and finish them off with either a centre TB or an end TB.. either would be ok.

[ed]

good stuff stewy, thanks

found this from TODA



but still would like to know the minimal bore-bore spacing that these things can tolerate

cheers
ed

[oldcorollas]

>>just measured port spacing.. end throttles are 262mm apart..
>>divide by 3 = 87.3mm apart


i have some pics as well. i think you could reduce that by 5mm and maybe a little more if you mod the adjustment tang
you have mail. the pic with adjuster, i just realised, has an end TB next to it, so no tang

[roadsailing]

righto, as I measure it the throttle spacing is near enough to 87.5mm, and there is about 4mm between the linkage nut and the linkage of the throttle next to it, so you could get the port spacing down to 83.5mm and would have to grind the linkages a little bit to get the adjusting screws to seat nicely.

If you did away with the nut and washer somehow you could lose another 7mm, but then it would be difficult to link, control or synchronise the throttles.





that help?

[Ben Wilson]

I don't know why everybody gets excited by the Toyota throttle bodies. They have a bizarre bolt pattern and no injector mount. Bike throttle bodies are a much better thing.

[takai]

Yeah, agreed on the AE101 ITBs, except when used on the 16v 4A.

I would go the GTR throttles in a heartbeat over them.

[roadsailing]

I don't know why everybody gets excited by the Toyota throttle bodies. They have a bizarre bolt pattern and no injector mount. Bike throttle bodies are a much better thing.

I like them because someone already carves out lumps of aluminium that they bolt to, that then bolts to a 16 valve 4AGE head, which has injector holes in it already.

But i agree, for anything else i would use something else or make up my own.

[jonathan yee]

the blacktop's also ahve a wierd poprt shape on the side that connect's to the runner's. they aren't round

[oldcorollas]

RB26 throttles might be too wide for some things, and weber based TB's are very wide...

the toyota throttles give an option for making the intake more compact.. at least widthways

[takai]

DCOE/GTR throttles are 90mm spacing, AE101 are 87.5mm
Not that much difference.

[oldcorollas]

oh, i thought i measured it as bigger,,, hmm they seem bigger

[ed]

yeah, theyre all very very similar

some people are gagging for these throttles on some things, so im looking at making a manifold that can accomodate the rb26, dcoe, and ae101 units universally

cheers
ed