Colt Triflo Mild Cam + A/T = Idel at 1000 rpm?

[epic1400cs]

I have installed Colt Triflo Mild cam recently onto my Aerodeck with automatic gear box. I like the cam very much but I am not sure about the ideling at the moment. It is common that if you fit sports cam you need to raise the idling speed a bit due to lack of torque at the bottom rpm so I did. Being A/T means when it is in drive ranges(D4, D3 or 2) and stand still, the rpm is less than the idle speed intially set. At the moment free idling rpm is around 1000 to 1200 rpm so that when the selector is in D, the rpm is around 750. If I try to make it lower, the engine stops.The problem is now in winter and when I start the engine, the warm up idling rpm is like 2000rpm and very roud - especially with straight exhaust it is good wake up call for mu neighbourhood. Also the shift shock from P to R or D is pretty big and I dont like it very much considering our rather fragile AT.

I am just wondering if there is anybody out there who knows how to lower the idling rpm without engine stops - like using cam gear to move the torque curve to lower rpm? The eigine is injection (A20A4 almost same as A20A3) by the way. No sales for 5 speed swap or non OEM A/T fluid or additive please.... Please also dont start 'that is how it is so you should cope with it' - I know that and thats why I am curious to find solution. Thanks

[rjudgey]

AT aren't designed for upgraded cams the change in vacuum pressure messes it all up and idling is just one of the results of upping the cam, it should idle at 1000rpm okay maybe slightly less but you may find that you might have to add a little more fuel or try adjusting the ignition timing to lower it might help as well. lower ignition timing will reduce idle speed maybe if you can just knock off 100rpm or more it might be okay worth a try. Also when i had a Teg with Auto and Concerto with D16Z with Auto found the best way to deal with high rpm cold start was to put it into D2 first then into reverse seemed to make less of a bang.

But really now that you are starting to add performance upgrades to the engine your first priority should be manual Box conersion as you said these box's are fragile and it won't stand much abuse and if you revving higher and producing more power its going to shorten life even more.

P.S. what happend to having a pint!!!

[epic1400cs]

lower ignition timing will reduce idle speed maybe if you can just knock off 100rpm or more it might be okay worth a try. Also when i had a Teg with Auto and Concerto with D16Z with Auto found the best way to deal with high rpm cold start was to put it into D2 first then into reverse seemed to make less of a bang.

Thats the sort of answer I wanted, thanks for your tip! By retard the timing, will it effect the out put power or it is minimal? I will try it tonight I think.

But really now that you are starting to add performance upgrades to the engine your first priority should be manual Box conersion as you said these box's are fragile and it won't stand much abuse and if you revving higher and producing more power its going to shorten life even more.

Yes, I understand that - I assume the mechanism of our A/T box is more or less idential to the one fitted to B20A which is 160bhp - its simply from my experience driving both of the box. I am hoping our box will stand up until my A20A4's bhp reach that level.(I know I am less ambitious that you are!)

P.S. what happend to having a pint!!!

Did we say before Christmas? no, sorry my bad, let me send you PM tonight.

[shepherd79]

with tryflow you should keep the stock idle speed.

[rjudgey]

Duration and lift is still more than stock and that effects the tuning and idle running with a manual it's not so critical as you just be more carefull with the Gas and clutch whereas the Auto it has to be able to idle at a certain speed and not stall. The problem he's getting is if he sets the idle to 1000rpm when it engages and drops the rpm to 750rpm it stalls the engine but if he sets the idle higher than 1000rpm it makes a loud bang when engaging the gears.

The lower ignition advance will just alter the power band a little as long as it's not huge amounts and i'm just talking moving it mm's not cm's then you should be fine if you move it all the way back or forward your engine will not run properly and your damage it. Mark where you have it at the moment there is a little pointer on the dizzy flange if you mark the cam bearing support that it mounts to then just try a couple of mm's retard which i think should be towards the front going towards the back advances, you'll be able to tell as the engine revs will pickup or slow down slowing down is retarding picking up is advancing the ignition.

[shepherd79]

he should be able to adjust to 850-900rpm without any problem.
most likely you don't have timing adjusted properly.

[epic1400cs]

Thanks guys.

Yeah, the problem is when the AT is engaged. I can set the idle as low as like 650 no problem but when the AT is in D or R it will be like 500 then even with OEM cam it will stall. When I replaced the cam, I didn't touch the idel screw or timing and it idled around 750 rpm in P range with no problem but it stalled when I stopped for traffic light in D range. Thats why I started to raise the idling rpm. 850 sounds very realistic and I will try it out soon.

[A20A1]

I just upped the mixture on my carb and made it run a bit richer at idle which helped it idle at 500 rpm.

But since you are EFI you don't really have that option.

[epic1400cs]

If I remeber correctly, your car is A/T right?

[rjudgey]

which is why i suggested the adjustable fuel pressure regulator if you up the pressure slightly it will run a bit richer at idle with your cam and maybe make it less likely to stall. FSE do one that will fit as i have one on mine. But i'd try the ignition timing you sure you got the dizzy on exactly the same after the camshaft swap? Just needs a bit of tinkering i'd imagine could take a look if you want when your around.

[epic1400cs]

I am in a toy shop! Yes, I should double check the timing first.
Will adjustable cam gear help at all?

[rjudgey]

no not really you can allways make your stock one adjustable mine is but it's a bit ghetto!! We'll see maybe if you haven't resolved it by Saturday i might be able to get it running better.

[carotman]

Maybe you could mess a bit with the idle boost solenoids if adjusting the timing doesn't work. Just a thought.

[Jasonf860]

When I first installed my Delta 272 cam, I had a hard time trying to get it to idle. I adjusted the timing and it started to idle better, but was still off. I drove it for a week before I realized that my timing belt was off by 2 teeth. Once I fixed that and readjusted the timing, it idled perfect.

[epic1400cs]

Yesterday, I tried to retard the timing a bit, may be one degree or less but as much as I could, as well as installing adjustable camgear(Golden Eagle one I bought from Ludi Mali ages ago).

I set the camgear as 3 degree advance to give lower rpm torque and it worked pretty well and now the idling is 700rpm or so and it gives excellent accelaration at the same time. The idling is almost same as with the normal cam. I might try how different it will be to set 2, 4, and 5 degree.

Only the problem I still have is the tapet noise - I set the clearance in 0.20mm ex 0.25mm but it makes noise so next time I will go in 0.25mm and ex 0.30mm.

[rjudgey]

Your going the wrong way, if you want your engine quieter which as yours nearly standard and you want it quiet you need the gap smaller, also depends what thickness oil your running too. The settings your using are for a high performance setup with an engine that runs hot. I'd go with the following.

Inlet valves .15mm
Exhaust .25mm (or try .20mm it will be okay and bit quieter)

The above is stock minimum clearance on A20 style engines.
If you oil is thin e.g. 5/30, 5/40, 0/40 sythetic try below:

Inlet valves .10mm
Exhaust valves .15mm

It also depends how you adjust them, the feeler gauges should drag through the rockers quite a bit if it's easy to pull out too loose, makes a big difference.

[epic1400cs]

After changing the cam, I have set intially

In 0.15mm
Ex 0.25mm

and the tapet was already noisy so I followed an advice from Colt - try make the gap of In tapet wider. I didn't change the Ex. Mmmm, actually ex might be the one making the noise. I should try Ex 0.20mm, too.

I always use castrol magnatec (mineral) so am I right that I dont have to go too narrow?
I always try to set the tapet with the feeler gauge drag a bit but not loose. I will pay more attention to be perfect next time. In anyway, thanks for your advice.

[A20A1]

If I remeber correctly, your car is A/T right?

Correct-o-mundo


valve lash page
https://www.3geez.com/forum/showthread.php?t=39319

Your going the wrong way, if you want your engine quieter which as yours nearly standard and you want it quiet you need the gap smaller, also depends what thickness oil your running too. The settings your using are for a high performance setup with an engine that runs hot. I'd go with the following.
Inlet valves .15mm
Exhaust .25mm (or try .20mm it will be okay and bit quieter)

0.0078in / 0.2000mm, I should have tried that perhaps for the exhaust... I never went lower then the lowest stock recommendation really.


0.0050in / 0.1270mm
0.0100in / 0.2540mm

[rjudgey]

Depends how hot the climate is as well, being as it's winter now and allready temps arearound 0-10 degreees C the gaps can be smaller, if it were summer and the engine was running hot then .25 would be more suitable, but i'd still say that .20 is still fine on a20 in summer for normal road car.

B20A specs are even finer and the valves aren't that much bigger or made from different materials and uses the same grade oil?

[Toohardtohandle]

About a month ago I had the Colt Cam installed in my 1988 (ex-i, 210,000km, auto). I took Geoff's advice and went with the "mild" tri-flow, since it's my daily driver. So as it stands today here are the current mod's I've done.

Pace Setter Header
K&N Air Filter
Colt Cam Mild Tri-Flow

Although I'm happy with the gains that I've made...I can't help but think the car should be doing better. I know, I know, I'm beening hurt for driving an automatic car. But the greatest difference I see is from about 60-70km to about 140-150km. And if I'm driving in D4 forget it. If I want any response at all I have to be driving in D3. Geoff was right, the biggest difference I noticed is when I'm driving on the highway and I want to pass someone, I drop it down to D3 and lots of pull right up to the redline. But the moment I push it back into D4, the fun is over. The same can be said about the bottom end.

So here's my question. Does anyone think that by adding a CAI and or a custom exhaust will it make a signifcant difference; either to my top or bottom end?

Thanks for your insight

[rjudgey]

Try these,
CAI kit.
Throttle body mods/remove Butterfly screws replace with countersunk, por tout the mouth and knife edge the inside of it for perfect flush fit with CAI.
FPR maybe some Accel injectors
4th Gen Map sensor
Exhaust system 2.25" mandrel bent tubing not crush by most cheap exhaust shops or just get pacesetter which is mandrel bent
Pacesetter Hi Flow Cat to go with the above
Maybe change the coil adn ignition system to MSD etc.
That should give you more pep most likely the exhaust is strangling the engine as it's only 1.75" on stock pipe but the rest will really liven things up for you .
Also not being funny your engine is quite tired i'd do a compression check first and see where your at if your rings are shot doesn't matter what you put on you'll still be slow. Also hope you used new rockers or had the old ones reconditioned or the lobes on your new camshaft will be fubar!!

[Toohardtohandle]

Thanks for the imput

And to answer your question "no" I didn't change the rockers, and I didn't based on what Colt Cams said and the mechanic that installed it said as well. If what you are saying is true...fuck am I going to be pissed!!!! Because I specifically asked that question. I had at one point stopped by the local exhaust shop and asked about changing what I currently have. They had said that by and large I had pretty good flow and that the minor gains that I would make probably wouldn't justify the expense? Can you or would you know (your best guess) what kind of hp I would gain from changing to either a ram air or CAI with a custom exhaust. Keeping in mind that I have a K&N in already. Keep in mind that I live in Canada and our dollar is just slightly higher than the Peso (lol).

[epic1400cs]

I am not sure if I am answering your question because I am not planning to install CAI but, I noticed significant difference after I have installed adjustable cam gear. Initially I have installed it and set to 3 degree retarded in order to lower the ideling speed without engine stall in D range. However, after I started driving the car on street, I realised that this set up made big difference - much bigger than when I simply installed the cam. I can feel much stronger torque from lower rpm. This is totally different from track or strip - you want have bhp at high rpm but on street the situation is quite different. I understand that adjustable cam gear is difficult to get but if you have a chance to come by, I recommend it.

D4 is pain especially when you accelarate from walking speed - it missed the gear sometime. If I need max accelaration I start with D3 with 1st gear(means full throttle) with left foot brake before start. Soon after AT shifts up to 2nd, I switch to 2 range then continue till its rpm reaches near red then back to D3 to shift up to 3rd gear, if you know what I mean.

Obviously, if you replace the exhaust, it will help the ex gas flow. Mine is 2" but with straight through silencers I could feel noticable difference in mid rpm.

For CAI I haven't tried it but some Honda tuning shop in Japan like Spoon says our car already have CAI with non-heat conduct piping. They also use normal air intake set up for their racing car because they dont want to change the "pulse" of incoming air defined by the piping design. Shortening the length of the CAI piping is good for high rpm but it may effect lower torque but I am not 100% sure. Only the mod the Spoon does is to remove the resonator (like branch piping next to battery) to smooth the air flow and use better air filter as far as I understand.

I have one AT throttle body with port job + slight big bore done by pro and that might help to give some more horses to your set up so let me know if you are interested.

[rjudgey]

whats the buttefly size? if it's bigger than stock i'll buy it from you.
Also with the exhaust it's way too small don't listen to the muffler man he hasn't got a clue, i was runnign stock exhaust on mine the pressure got so bad that it was tearing the exhaust apart from not the welds but the acutal tubing, and this was new exhaust not old one thats rusted out. so in the end got so fed up of having to keep sending it back to be repaired i got a custom 2.25" done, but i later found out that they used a joint that was only 2" and that the bends were crush type and not mandrel bent which is whats causing my engine to bttleneck at 7.5k rpm and also keeping power to just just under 200bhp, before i had exhaust done engine was putting down about 165bhp roughly had it changed and boy i felt like a different engine it was quite frankly scary driving it for the first time scared me and the exhaust bloke!!! After about a week or so got used to it and then went looking for more power. Now i have the bigger valves and few other tweeks and a 285 camshaft i'm looking at a Pacestter header, minus the secondary pipes which will be custom with 2.25" main pipe going straight to custom 2.25" mandrel bent system single exit sports silencers but not straight through would be way too noisy with the webers have to keep at 105db at couple of meters at 2500rpm from exhaust for noise regs on track!!!
And yes Adjustable cam gear will help too you can mod your old one to see if it helps also, or buy a second one from scrappy to experiment with.
As for the rockers, it depends on how badly worn they were, if they were scored and have wear patches on them it will damage the lobes on the camshaft after a while, but if they were nice a clean and shiny you should be okay, you can recondition them i did takes alot of patience you need lots of wet and dry and a totally dead flat surface like thick perspex or glass base then a case of rubbing them all round evenly till they are all polished up and nice and round with no indentations and no marks like new. If you looked at your old ones and you didn't see any marks don't worry about it but with an engine with 200k plus km's i'd be surprised if they were in that good a condition. You never know wiht the right oil and regular 3k mile change all it's life it might be but most people never look after there cars that well!!

[Toohardtohandle]

whats the buttefly size? if it's bigger than stock i'll buy it from you.
Also with the exhaust it's way too small don't listen to the muffler man he hasn't got a clue, i was runnign stock exhaust on mine the pressure got so bad that it was tearing the exhaust apart from not the welds but the acutal tubing, and this was new exhaust not old one thats rusted out. so in the end got so fed up of having to keep sending it back to be repaired i got a custom 2.25" done, but i later found out that they used a joint that was only 2" and that the bends were crush type and not mandrel bent which is whats causing my engine to bttleneck at 7.5k rpm and also keeping power to just just under 200bhp, before i had exhaust done engine was putting down about 165bhp roughly had it changed and boy i felt like a different engine it was quite frankly scary driving it for the first time scared me and the exhaust bloke!!! After about a week or so got used to it and then went looking for more power. Now i have the bigger valves and few other tweeks and a 285 camshaft i'm looking at a Pacestter header, minus the secondary pipes which will be custom with 2.25" main pipe going straight to custom 2.25" mandrel bent system single exit sports silencers but not straight through would be way too noisy with the webers have to keep at 105db at couple of meters at 2500rpm from exhaust for noise regs on track!!!
And yes Adjustable cam gear will help too you can mod your old one to see if it helps also, or buy a second one from scrappy to experiment with.
As for the rockers, it depends on how badly worn they were, if they were scored and have wear patches on them it will damage the lobes on the camshaft after a while, but if they were nice a clean and shiny you should be okay, you can recondition them i did takes alot of patience you need lots of wet and dry and a totally dead flat surface like thick perspex or glass base then a case of rubbing them all round evenly till they are all polished up and nice and round with no indentations and no marks like new. If you looked at your old ones and you didn't see any marks don't worry about it but with an engine with 200k plus km's i'd be surprised if they were in that good a condition. You never know wiht the right oil and regular 3k mile change all it's life it might be but most people never look after there cars that well!!

First and foremost...thank you for your responses, much appreciated. At this point I'm feeling like "in for a penny in for a pound". I've started the mods, and now I'm wondering where I should go now. The cam gear would have been nice to replace while I was having the cam installed (I'm such a dumbass). Oh well live and learn. There is a performance shop not too far away from where I live and I was planning on going in and talking to the custom exhaust guy and seeing what he has to say (a second opinion if you will).

Can either of you recommend a CAI that will fit into my car? And what are your max speeds respectfully. As I mentioned in my earlier post...I hit about 180km and that's about it. Are you reaching higher speeds with your cars, and if so can you give me some sort of an idea what speeds you are reaching?

Thanks again for your insight