Discussion in 'Discussion Forum' started by Dr.Jeff, Jun 22, 2018.
Did he mention camshaft, was it also stock?
He used sport cams, but we didn't discuss the details. I'm planning to move the sport cam from my 1500 as well but I'm a little bit worried the duration might be too long.
The main thing I have heard about cams with a turbo engine is to avoid valve overlap (both intake and exhaust open at the same time). Some "performance" cams will have more overlap, so be sure to check the specifications. To avoid overlap, a cam with higher lift is better than one with long durations. And it has also been said a cam with good torque/low end performance is better to help before the boost comes on (improve power/initial acceleration during turbo lag). Again, some performance cams tend to be the opposite, they focus on top end (high RPM) power, not torque. So in some cases a stock cam is said to actually be better than a high performance cam with a turbo because of these things. But with the American version of the X1/9 that is not true - the cam we got is that bad. However you guys in Europe have much better stock cams ("Euro spec"), so maybe that is a good choice? I have a aftermarket cam from one of the USA vendors that is ground to be similar to the stock Euro spec cam, but with a little more lift (however the overall quality is not the best). Over there companies like Piper and Cat make specific performance cams for the Uno Turbo and Punto GT that should be good. But here they are difficult to get making them much too expensive with the shipping cost. I would like to be able to compare those cams with the stock Euro spec 1500 cam to see how they are different. But cam makers like to give the specs in non standard terms, or not give any info at all. Plus I do not have enough cam knowledge to be able to interpret them well enough. If anyone can offer more information about them it would be a big help. Also if anyone in Europe replaces their stock cam with a aftermarket one please let me know, I would like to buy a good stock 1500 Euro spec or UT or Punto GT cam.
I bought one just like the one on the video. I must admit to not looking too deeply into the ability of the cheaper one as far as heat transfer goes as the problem I had with it was that it just wouldn't flow enough air, leading to increasing boost to overcome the restrictions, leading to increase temperatures , etc ,etc. We very quickly knocked that on the head and bought a PWR with instantly better results allowing less boost, lower temperatures and more control overall for higher output. Having had the chance to compare the internals of both it's obvious why the PWR flows way better. However, if you're not going for higher hp then the cheaper one I guess would do.
Yes, overlap should be avoided and actually what I meant with duration. The midrange is good in my 1500, but is not very lively above 6k. I don't know what cam I currently have but I think it is a 12B 33/73, lift 9.4mm and 110°. Is there a way to verify this? Is there a marking on the cam? It is still in my 1500, and I will not tear it down until late October.
This is probably not the best cam to go for, but this is what I have. And the UT standard cam of course.
UT standart cam is not the way to go?
I am amateur.
I’m going to use 1.6 from Punto with all stock internals, valve springs from UT and turbo system from UT. Couln’t find any information witch cam to use 1.6NA or UT, so there is still 1.6 cam.
I don't know anything about the stock cams for any models other than the X. But I assume the cam that came in a factory turbo model would be a decent one to use compared to any non turbo model factory cams? Obviously there are aftermarket options, but no idea how they actually compare.
perhaps go back a couple of steps and ask:
what is the pressure ratio across the engine .......and what influences this
then ask - how does the engine see the cam for different pressure regimnes .......
for an "effiecent" "turbo setup" the pressure ratio should be close to 1 : 1 .......
you can then think about:
1. duration requires for rpm band.
2. overlap with regards to the above.......
3. other camshaft requirements to enable air to be moved
Could you explain "pressure ratio across the engine"?
Might be something that I use every day but don't use those terms.
Based on previous comments, I believe it is referring to the boost pressure differential (or loss) as it travels through the entire system. Restrictions will cause back pressure and raise temps. So if you can make everything offer zero resistance then you will get the most performance with the least temp increase (i.e. more efficient). The head and valve train will likely be the largest restriction area. Unfortunately there is only so much that can be done with these heads on a low-budget, home-based build. But I imagine the comment was related more to cam choice in this instance. Hopefully Simon can offer suggestions for a good cam choice?
Thanks Simon. It will take me awhile to go through this.
Next bite of the UT elephant...
UT Mk1 has no Cam Position Sensor but measures engine speed by reading the flywheel. I don't think a modern aftermarket ECU can handle that so I am looking for an alternative.
It seems to be possible to drill a hole in the cam wheel, tap it to fit a M8 bolt. The bolt will act as trigger pin. A short or flat sensor should be possible to fasten on the cam shaft housing somewhere close to the cam wheel, 2mm away from the sweeping bolt. A digital trigger seems to be better and more accurate than a Hall Sensor.
I've seen other discussions here on X-web about converting the distributor to a Cam Sensor, but I am not sure that's the best way or even realistic. I rather not keep the distributor as it would require modification to work as a sensor. It would also be in the way for tubes and Inter Cooler etc.
The resolution on the stock Crank Position Sensor (2 teeth only) is not good enough and MaxxECU requires a 36-1 or 60-2 trigger wheel. I've found a 60-2 teeth crown wheel that fits perfectly, and to be welded on to the stock crank wheel.
Must the 60-2 wheel be positioned relative to TDC or will the ECU learn the crank position (just like it does with the cam sensor)?
Probably will other sensors need replacement as well, but I start with these two.
The position of the crank trigger wheel is dependant on the position of the sensor and how your ECU is programmed. The two must be placed relative to one another so they fire off the missing tooth at the correct time. Therefore they can be anywhere around the crank pulley so long as both are properly placed together. But also check the setup instructions for your ECU to see if it has any specific requirements. I can link the instructions for this from a MegaSquirt ECU if it will help (it explains things fairly simply). In a earlier post I showed how I made the crank trigger arrangement, but it is similar to what you described.
There have been many examples of making cam position triggers as you described, including some for the SOHC in particular. I'll look to see if I have any pics saved, but there may have been some posted earlier in this thread. There was a good explanation of the type of sensors that can be used on the forum...maybe also earlier in this thread(?), so scroll back and see if it comes up.
A hall sensor is a digital sensor as in it makes a square wave, a variable reluctance sensor is analog and works like an electric guitar pickup and produces a sine wave.
Finally got the specs on the injectors. 360cc Bosch with suitable adaptors. The fueling control is very good across the range with the Maxx ecu. With the old ecu it was struggling at lower rpm and over fueling, also the progression was in jerky steps, but then it is technology that is at least 30yrs old.
I'm glad to hear the inputs from everyone about injector sizes, it helps to support what I had previously determined for my particular project needs (based on things I had read).
Yes, thanks for all input it has been very useful. This is a world class forum.
I had difficulties finding EV1 injectors in range of 350-400cc so yesterday I ordered 440cc MSP injectors that will work with my hose mod and top adapters. Lots of people in UK are running their UT's with even bigger injectors w/o problems, and I think the super fast MaxxECU wll handle it just like you say Speedy Fiat. I also ordered individual Bosch ignition coils and a 4 channel (sequential) trigger so I am slowly getting there. Fueling done, ignition done, sensors done. Turbo and IC next... And I almost forgot, clutch. -Seems to be tricky with a X1/9 gearbox on an UT flywheel. OR, I'll eventually go for the X1/9 flywheel but finding a clutch capable of 200-250hp and lot of torque is not easy.
I am not certain but I recall something about the UT flywheel is not a direct fit with the X's gearbox? I believe some grinding of the bell housing is needed to clear it. As you will not be needing the UT's flywheel trigger, then maybe better to use the X flywheel? Here in the US there are a couple companies that offer performance clutches (of various levels) for the X. I would think there are even more options available in Europe.
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