basically ive read a few posts by essthree about his modified throttle body and how it gave a dyno proven 3 or 5bhp (cant remember) anyone know what the principal/logic is behind it? i understand that its imporant to have the body match ported to the manifold ive heard about people altering the butteryfly to smooth the airflow etc. anyone got more to add?
as you said, modified to optimum flow rate. seen often on hondas - gives 4-5bhp is there to. could just be people talking bum gravey though. I've seen cars produce 5bhp+ more in the cold morning air than they do at mid-day temps...
definately worth it, you do get a sharper throttle response. You can do it yourself with a dremel, remove the throttle body whilst leaving the plate from in front in place and use a highlighter pen to draw over any metal on the throttle body and get grinding. you can take a surprising amount of metal off from the gap/ridge which is between the smaller and larger chambers. have a look at this site . il see if i can get the pics from my bro of his throttle body pre an post porting!!!! very noticable difference!
I've done a few of these. Easiest way is to put the body in a lathe and turn the bore straight through, removing the large hump before the butterfly. Just DON'T touch the area where the butterfly sits or you'll have destroyed the body. PS, you avoiding my emails regarding the flywheels ?
haha ive had trouble with a courier not being able to collect when theyve turned up to pick them up and no one has been in. its getting sorted though. they have been repackaged once already when the puppies unwrapped them after their dinner lol
i found more posts from essthree saying it made the throttle response jerky with small input. i think ill leave mine i thought that hump was to add velocity. will have a look to see if it is matched to the manifold though
lol no problems. I've done a few of them, never had anyone mention anything about jerky throttle response though. Suppose for different states of tune it'll work differently. The last one I did went onto a well spec'd Seat ABF with a shed head etc and schrick cams. Owner was very pleased. But like you said, if the hump is there to increase velocity, on a mild engine being used daily it may not be well suited.
Well I'm in the process of getting a hotgolf'd flywheel and maybe get my other throttle body hotgolf'd as well
thats no use me to, i need a spare throttle body. or send your flowed one to me, ill send mine to hotgolf and hell send that to you lol
Just for info: I did mine using a lathe with a 4 jaw chuck...and I've messed up one or two over the years to! Mine is taken out to a knife edge at the inlet to the TB, and match ported to the manifold at the rear, with the ramps removed. It gave between 3 and 5 BHP gain on Star Performances rollers, with the car remainng strapped to the rollers whilst I swapped the TBs back and forward...I did 3 or 4 swaps and each time the modified TB gave a gain of 3 - 5 BHP (in conjunction with a modified Arbox and other engine work too BTW...but back to back testing involved only swapping the TB) Town running can be a pain - especially if a light flywheel is fitted as it will bog down and kangaroo more than standard...you have to blip the throttle to clear it - a function of the slow air speed at just off idle now the 'ramps' have been removed, it seems. Some pics:
thanks mate. youve done a lot of work to yours so i am following your footsteps to an extent! no chance you have a spare one knocking around? i was hoping to get one on before its trip to the ring. ive got a pic of your pipework (throttle to airbox) on my comp at home... aiming to replicate that too haha
I don't think I have a spare...I have so many parts sitting in boxes in the garage loft, that I forget...but I can't remember seeing one in the last couple of years.
matt me and my housemate are going to pick up an abf to stick in his ibiza, he is selling the bits off his old engine if you want to buy the TB??
Heres a couple of pics of mine - Note that the edge of my TB is matched to the standard rubber boot and that's the reason it's variable thickness and not knife edged as Glenns is: Pics back up:
OFF TOPIC - Sort of!! how big is the abf throttle? I have a passat auto tb which im going to use for the Megasquirt Maybe i should get one of these if they are bigger if not i might have to get it modded... eh mart
