The Ultimate FA20 ITB thread.

[Tokay444]

Sooooo, pretty much as I said it would go.

[sato]

So, power was cutoff at 6600rpm, more or less? The effect looks similar to the crawford power blocks. If it has a full exhaust, then how can we tell those results are direct result of the ITB? Any before Dyno results for comparo on that page?

[PulsarBeeerz]

Originally Posted by sato

So, power was cutoff at 6600rpm, more or less? The effect looks similar to the crawford power blocks. If it has a full exhaust, then how can we tell those results are direct result of the ITB? Any before Dyno results for comparo on that page?

The before and after dyno is shown. It had a full exhaust and was tuned then they added the ITBs and tuned them.

[Tokay444]

Juice ain't worth the squeeze folks.

[PulsarBeeerz]

Originally Posted by Tokay444

Juice ain't worth the squeeze folks.

I think most had come to that conclusion with the lack of results awhile ago. I will say they seem work better without a plenum but require a standalone to be optimized.

[Turdinator]

Originally Posted by PulsarBeeerz

I stand corrected. IIRC the one who lost power may of had cams. Here is an otherwise stock long block with a full exhaust on 93 using the supplied IM.



You'll have to do some sifting but the info is there.

https://www.facebook.com/groups/NaturallyAspirated86

I don't think its a total loss. It looks like a solid torque increase up until 6k rpm. The car would probably be noticeably quicker than stock. If you had the time to play with runner lengths and maybe even the throttle size i am sure you could shift the torque higher and make more power.

[PulsarBeeerz]

Originally Posted by Turdinator

I don't think its a total loss. It looks like a solid torque increase up until 6k rpm. The car would probably be noticeably quicker than stock. If you had the time to play with runner lengths and maybe even the throttle size i am sure you could shift the torque higher and make more power.

One of the owners agree with that sentiment. The other one says he is determined to extract more from them so how.. Presently both used the supplied IM so I don't think they can play with runner lengths. It's pretty obvious the butterflies are undersized for a 12.5:1 comp 2.0l engine and unfortunately the TBs are already bored over from the original 45mm to 48mm so there isn't much material left to get to 50-52mm. However like I said earlier with a standalone and runners open atmosphere they start to makes more sense. This was on 94oct.

[sato]

Originally Posted by PulsarBeeerz

The before and after dyno is shown. It had a full exhaust and was tuned then they added the ITBs and tuned them.

The those are some nice gains indeed!

[Hades]

Originally Posted by Turdinator

I don't think its a total loss. It looks like a solid torque increase up until 6k rpm. The car would probably be noticeably quicker than stock. If you had the time to play with runner lengths and maybe even the throttle size i am sure you could shift the torque higher and make more power.

Yea, that actually looks pretty good. Sure, we all want more peak power, but the powerband is wider & stronger which would result in a quicker car. Downside is less high RPM fun... perhaps with some further tuning/development we could see better results up top.

[Tokay444]

Needs larger diameter throttle bodies.

[PulsarBeeerz]

Originally Posted by Tokay444

Needs larger diameter throttle bodies.

Correct, as I said earlier..

However at that point you might as well make your own custom kit and forgo the Greedy kit completely as you wouldn't be using much of it at all. Past racing classifications and novelty the cost to source50-52mm ITBs for this layout for the mid-range and last 10whp NA one could build a legit 2.2-2.4L for the same cost and not need a standalone to run it.

[Turdinator]

Originally Posted by Tokay444

Needs larger diameter throttle bodies.

Why do you think that and not different runner lengths?

[Tokay444]

Originally Posted by Turdinator

Why do you think that and not different runner lengths?

Because the restriction is in the diameter.

[Turdinator]

Originally Posted by Tokay444

Because the restriction is in the diameter.

It seems like they are using 4AGE 20v ITBs. The start of the thread lists the throttle sizes as 45mm for the Sard and 48mm for the Greddy. I would have thought the 48mms would be enough for this motor. Do we know which was used in for this dyno? The Sard does seem to have a greater volume plenum and shorter runners which I think would be preferable. Maybe a mix and match would net better results. I also know you can get 50mm TBs from people like Toda. So if its only the TB size that is restricting things there are ways around that if you are prepared to spend a little extra.