No, I didn't give up, but could use some help with the last push

[tdskip]

Hi folks - I know I went dark there for a bit but I did not give up on the SR20DE swap into the 1967 Triumph. I got busy with work, life, etc, but I am on the final push now.

 

With some extra phone help from Alleycat - which was very much appreciated - I swapped out my MAF and she runs and will idle now. In fact, I was able to actually bring her on the street for the first of what will likely be many shake down runs. Happy to say the 5 speed is a happy unit, which is a big plus because I wasn't sure of its condition when bought along with the JDM SR20DE.

 

There are three main issues I need to get sorted out that I am hoping to get some help on;

 

1) She runs and seems happy with good power, her idle will get stuck at around 3000 once warmed up. It does not appear to be a physical throttle body issue, and I did clean it before buttoning everything back up. Once it climbs up there it won't return back to a proper idle RPM and I have to shut it off. Any likely suspects on that? Was thinking vacuum leak but that would only show up once warmed up, would it?

 

2) My clutch engagement is way too high of an effort and very abrupt. I am using the OEM Triumph 3/4 bore clutch master and a Silvia slave. All are new, and the clutch is a SR20DET unit, also new. My guess is I need a smaller bore Clutch Master, but wanted to see if you guys had any other ideas for me? What do you use in your SR20DE swaps?

 

3) Are there any local SoCal events where I can meet you guys to buy lunch / drinks to say a proper Thank You?

 

Thanks in advance, and happy motoring!

 

 

 

[datzenmike]

A smaller master will be easier to move but move less fluid. Less fluid will mean less travel. The 3/4 master and Sylvia slave sounds about right but the Nissan clutch pedal may be longer than the Triumph and have more leverage.

[flatcat19]

IAC valve would create a high idle condition when warmed up.

[tdskip]

IAC valve would create a high idle condition when warmed up.

 

Ah, well that sounds like a likely suspect. Are the IAC valves a take it off and clean it thing, or better to replace? If replacing can I swap out a generic Nissan one from a G20 or similar?

 

EDIT - is it possible to clean it in place?

 

Thanks for the response!

[tdskip]

A smaller master will be easier to move but move less fluid. Less fluid will mean less travel. The 3/4 master and Sylvia slave sounds about right but the Nissan clutch pedal may be longer than the Triumph and have more leverage.

 

Thanks Mike.

 

Less pedal travel will make it worse, and if that bore size and slave combo is what people use then I suppose I should leave that alone.

 

Wonder how I can get more mechanical leverage in there.....

[q-tip]

Iac should be adjustable, my ka is,

[datzenmike]

I think that would be difficult. I'll try to remember when I get home to measure a Datsun clutch pedal from the fulcrum point down to the push rod for the master and the overall length. This would give you some measure of the mechanical advantage involved. A total guess would be 4 to one?. 

 

 

I looked up the pedal travel for my 710 and it's 7" for this I get about 1" of clutch slave travel. I think the master and slave are both 3/4" so it's assumed that the master also travels about 1 inch?

 

Have you ever driven an old 60s Chev? The clutches on them were fantastically stiff. I remember as a 20 year old with strong legs having trouble letting the pedal up without it shoving your knee into your chin.

[Stoffregen Motorsports]

When I swapped in the Toyota 4AGE Black-Top setup into a '65 Sunbeam, I used the original (AP, I think) Sunbeam master. Of course that was on an entirely different car with a totally different engine/trans, but the point is, I bet there's an original looking master available from some other application that may have a smaller bore.

 

Or you could get the Nissan master and, as mentioned already, double check the fulcrum/leverage/pedal travel of the pedal. If it turns out that the pedal travel is a problem, you could always install a stop.

[tdskip]

I think that would be difficult. I'll try to remember when I get home to measure a Datsun clutch pedal from the fulcrum point down to the push rod for the master and the overall length. This would give you some measure of the mechanical advantage involved. A total guess would be 4 to one?. 

 

 

I looked up the pedal travel for my 710 and it's 7" for this I get about 1" of clutch slave travel. I think the master and slave are both 3/4" so it's assumed that the master also travels about 1 inch?

 

Have you ever driven an old 60s Chev? The clutches on them were fantastically stiff. I remember as a 20 year old with strong legs having trouble letting the pedal up without it shoving your knee into your chin.

 

Thanks Mike - will measure. Would like to avoid the Chevy truck experience if possible, I keep inadvertently doing burn outs.

[tdskip]

When I swapped in the Toyota 4AGE Black-Top setup into a '65 Sunbeam, I used the original (AP, I think) Sunbeam master. Of course that was on an entirely different car with a totally different engine/trans, but the point is, I bet there's an original looking master available from some other application that may have a smaller bore.

 

Or you could get the Nissan master and, as mentioned already, double check the fulcrum/leverage/pedal travel of the pedal. If it turns out that the pedal travel is a problem, you could always install a stop.

 

Hi - thanks for the response.

[datzenmike]

I have a pedal set but all I know is it's Datun... could be from a truck. Anyway they will be similar. I get 6cm from fulcrum down to the pushrod and 30 cm from fulcrum down to center of the pedal pad... so 5 to one advantage.

 

Master is 5/8"

Slave is 3/4"

[tdskip]

I have a pedal set but all I know is it's Datun... could be from a truck. Anyway they will be similar. I get 6cm from fulcrum down to the pushrod and 30 cm from fulcrum down to center of the pedal pad... so 5 to one advantage.

 

Master is 5/8"

Slave is 3/4"

 

Hi - if I am doing this right I have about 5 cm from the fulcrum to the master pushrod, and about 26 cm from where the clutch pedal is hung to the middle of the clutch pedal.

 

EDIT - wouldn't one option from here be to leave the bore on master & slave the same but mount the clutch master cylinder up higher so I can use a longer pedal?

[datzenmike]

I guess so if there's room.

[tdskip]

IAC valve would create a high idle condition when warmed up.

 

I did the brake cleaner test looking for vacuum leaks and found an area on top of the engine that changed the engine RPM when I sprayed it. Looking at it made me realize it was the idle control valve (ICV). I pulled the ICV off, turns out it was right on top of the engine and couldn't be any easier to access, and it was totally gunked up with soot. Like totally. After some very judicious spraying with carb cleaner to clean it back to clean metal inside and letting it swirl around to clean the solenoid I reinstalled it and made sure I had a good seal. Holy cow the car is transformed. I was able to actually drive it around the block without protest. Even better she pulls cleanly and idles better (not as smoothly as she should, but workable).

 

I didn't really push her too hard but my theory about less weight and a lower CG appear to have been reasonable as she is noticeably lighter on her feet and changes direction more readily, Chalk another one up for the Ratsun forum. Thanks to all of you for the help, encouragement, and patience you have shown me.

 

I am still doing burn outs in the drive way due to the clutch engagement / heaviness issue however.