So, I was lacking a ton of power. Low down, it seemed to be fine, but then at higher RPM, car was making lots of sound but no power.

Figured... that was just that N/A lack of power. But, when I pulled off my intake elbow, etc. I looked at the first upper butterfly. It was partially opened. But just barely. So, I had heard of the dashpot, and it's purpose. So, I wanted to see if it was working. So, at first I put everything back together, and had a friend sit in the car and rev high, then let go of gas quick. What did I see? Nothing. The thing that should have been moving that butterfly to open wasn't moving at all. I thought that was weird, so I attatched a device that let me either pull, or push air into the vacuum tube... and, what did i see? Nothing again. Pushed on the dashpot a little... it was stuck.

So, after a little forcing, etc. I forced the front butterfly open, and zip-tied it temporarily. I am going to be doing the TB mod, and emissions removal next week, so, till then.

What did I notice? Higher RPM appears to have a ton more power. But maybe that is just the butt dyno being fooled. Dunno, I like it better. Maybe I can finally beat a civic......

Anyways, thought I would share. Check that dashpot! Make sure it is working and not stuck...

 

This is what we need. More people with threads about what FIXES things..

 

LoL.

I can't tell if you are being sarcastic or not. Damn internet... why can't font express sarcasm?

Anyways. It would probably be better to replace the dashpot rather then pulling it. But, I am a poor kid, like most FC owners. Don't want to spend the money for a new one, and there aren't many FC's in this area at the junkyards. And if there are, the engines don't stay there long.

I think all the dashpot does is... when you let go of the gas quickly, it just closes slowly?

J-Rat, I really don't understand.

I was mostly posting that I was glad to find lost power.

If you were serious, then sorry. I am just used to only getting flamed. Tends to be the "cool" trend on these boards.

 

The NA's TB doesn't actually have a dashpot, it's just a vacuum actuator. It pulls the upstream secondary throttles closed when the engine's cold to prevent you romping on it, and they spring open once the engine warms up. They stay open they whole time the engine's warm. Turbos on the other have have a dashpot built onto the actuator, and the upstream secondary throttles open and close with the downstream ones. The dashpot prevents them opening too fast and causing a stumble.

As long as you normally treat your cold engine nicely anyway, there's no problem with removing the double throttle system. There'll be no gains either.

 

I was serious.

 

i was looking at my car to day and as took the elbow off. I noticed that my upper butterflys where fully open. the car has not run for about 2 weeks. they are not tied open or any thing. chould this be bad?

 

Most who frequent the lounge will be able to tell you that the official color of sarcasm is teal.

https://www.rx7club.com/lounge-192/official-color-sarcasm-574244/

 

Ahh, why teal for sarcasm?

Anywho. The car was warm when I took the elbow off, and the front plates were closed. Thanks for the info though. Guess it wasn't a dashpot, but the other thing.

Thanks for the information about what it is supposed to do.

 

ok, i'm confused. does someone have a pic of this not-really-a-dashpot-thing? Is it on the throttle body? Is it something that opens the throttle body valves (butterfly?)?
I don't have access to my haynes manual right now.

 

ussually a lack of top end is due to the 5th and 6th ports not opening u sure those are working?

 

yeah I would like pics of what to look for on my 86 n/a basically if I pull the elbow all 6 of the butterflies should open easily right?

Dave

 

I am pretty sure they are. The sleeves have been removed.

So, with that top front butterfly closed I shouldn't have noticed a lack of power?

I am going to be putting my sleeves back in, in addition to all the S5 VDI stuff, electronically actuated.

 

That's how they're supposed to be. When the engine's started cold the manifold vac acting on the actuator will close them until the engine warms up.

Look in the FSM, page F1-37. There are two throttles in each secondary bore, and the front ones are operated by the actuator.

There's only five. The primary throttle and rear secondary throttles are operated sequentially by the gas pedal. The front secondary throttles are held open by the actuator spring, and should close easily by hand and spring back open.

Of course you should, you were running mostly on the primary ports. The engine was strangled.