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stix012
16th Jul 2016, 07:49 PM
My Son needed a larger throttle body for his Roll Racer but couldn't afford one so silly me said I would have a go at making one.363382

Michael G
16th Jul 2016, 08:00 PM
Looks interesting. Can we have a blow by blow description with pics?

Michael

stix012
16th Jul 2016, 08:18 PM
Sorry i only have the one pic and it has gone away to be fitted , it is copied from a "Fast" 2000 cfm throttle body.

KBs PensNmore
16th Jul 2016, 10:10 PM
Sorry i only have the one pic and it has gone away to be fitted , it is copied from a "Fast" 2000 cfm throttle body.

Well, seeing that there is only the one pic available, any chance of, to use Michael's words "Can we have a blow by blow description" without pics, PLEASE:D
By the way, whats a Roll Racer? Please explain!!:?
Kryn

stix012
17th Jul 2016, 09:01 AM
Queensland Raceway do Roll Racing about one Saturday evening a month , cars pair up coming around turn 6 coming onto the front straight and do a rolling start race to the finish line at the control tower (about two thirds of the straight length) and slow down before turn one.
You can get quite a few runs for your money and is an outlet for boy racers instead of doing it on the street , also a good money maker for the organisers , they also do Drifting and Burnouts most Friday evenings.

stix012
18th Jul 2016, 10:52 AM
Had a think and there are a couple of pics I can add , the most asked question I get is how do you make the butterfly's , it is not that hard really , you use a shortish piece of bar stock slightly smaller than the required diameter of butterfly and machine one end across the the full diameter to the required angle , in this case ten degrees , then drill and tap mounting holes across the centre line , cut an over size disk from brass sheet and drill mounting holes , screw it to the mandrill's angled face and then machine to required diameter in the lathe , in this case I gave them .001" clearance , too much clearance and it may suck too much air to to get a low enough idle.363412363413I hope that explanation is clear enough for everyone.
Here also is a pic of the form cutter that was used to radius the tops of the throttle bores.363415

Ryan in Melbour
18th Jul 2016, 11:38 AM
so is it a completely new throttle body or just a bore, radius and new top plate for an existing set up?

stix012
18th Jul 2016, 01:22 PM
Completely new , it was just one of those moments when you look at something and foolishly express your opinion "I can make you one of those".

KBs PensNmore
19th Jul 2016, 12:02 AM
Thanks for the update. What size Aluminium did you use and did he send down a sample for the holes etc? What size holes for the butterflies and air intake, the boring tool doesn't really give an indication of sizes etc.
Interesting piece of work, did it make him go faster/quicker?
Kryn

stix012
19th Jul 2016, 09:07 AM
This whole thing started because my boys tuner borrowed an American throttle body and as they are always looking for more horsepower tried it on my boys engine , a stroker LS Chev in a VT Comodore , it was making 496 HP at the wheels through an auto (there is a bigger loss through an auto than with a manual to the back wheels) with a 1300 cfm t/b and when they bolted on the 2000 cfm t/b it went 516 and more all through the rev range thus his wanting one.
I did not have a single piece of alloy big enough for the project had to use a 6 1/4" x 7" piece for the base and an 8" disk for the top bolted together.
The throttle bores are 2 1/4".

Harry72
19th Jul 2016, 02:29 PM
I find it amazing a 1300cfm TB is too small:oo: even on a big stroker motor!

stix012
12th Sep 2016, 01:46 PM
https://www.facebook.com/grant.grinter/videos/10154125576698292/

This is the boys black Commodore that the throttle body is fitted to.

KBs PensNmore
12th Sep 2016, 05:16 PM
Hope you don't mind stix I forwarded the threads on the throttle body to my son, for one of his burn out cars. He has several, his latest is a Datsun coupe 1200, I think it is, headed for a commodore V8 with a monsterous blower sitting on top transplant, depending on how it goes, could end up being a drag car.
Kryn

stix012
12th Sep 2016, 08:58 PM
Not a problem,the young bloke has two 1200 sedans,one being set up with LS V8 that was to be the same as your boys before he built his S14 drift car , here is a link to his Facebook page https://www.facebook.com/SILKE-Fabrication-Pty-Ltd-299953456684161/ you can see some of his work.His older brother is a drag racer , has a 1200 wagon with SR DET best ET 8.89 @ 148 from memory.
I know we are getting a bit off topic but I would like to see some of your boys pics if ok.
Jim.

KBs PensNmore
13th Sep 2016, 01:49 AM
Thanks for the link Jim, your lad certainly does some nice work, really like the door trims and rear parcel shelf treatment. That looks like a mean eFy with the twin snails. My lads burnout car is a LH Torana with mini tubbed rear arches, cleaned up firewall (metal finished) and the battery tray areas replaced due to the metal cancer, done by yours truly. He's running rear tyres, that people can't work out how it was done to fit them. Value of the car was $50K before it went into the impound yard 2 years ago, now $3-4K, rust, faded paint, 4 bucket seats (2 front 2 rear) material faded as the car was kept outside, he gets his licence back August next year, he lost it in 2005, initially for 6 months, DUI, DWD, (Driving While Disqualified), the score adds up after a while. Hopefully he's learnt his lesson.
Will get some pics of his toys, next time I see him. A friend just emailed me 2 pics of his son's new car, the son is 60?? As they say, the difference between men and boys is the price of the toys.
364189364190

stix012
5th Oct 2016, 12:58 PM
Her is a video of the black Commodore with the throttle body doing some quarter miles at Willowbank.
In the third run he is racing his brother in the Datsun 1200 wagon.
https://www.facebook.com/DragRacingTimesAustralia/videos/1734916430104301/

MasterSpoon
5th Oct 2016, 01:34 PM
That last run at about the 1:10 mark in the video looks like it's tried to kick on him, good job keeping it together