Turbo systems for X1/9's

Bjorn, I'm not sure if I completely followed what you did. Does the hose go into the intake manifold's injector bore, then the injector go into the hose? In other words it replaces the o-ring (Volvo) or round rubber mount (Fiat)? If that is what you have done then I'm thinking it might be as well to use the stock injector plastic mount. Will the Volvo injector fit in it? The Fiat injector does have a o-ring, so I do not think the plastic mount would break. But maybe I misunderstood, sorry.

I doubt that how far the injector tip sticks into the manifold would make too much difference. As you say there is still the other end to deal with. Have you looked at the various injector adaptors that are made for converting injector types (like in this case from hose-top to push-in)?

Regarding a turbo upgrade. Naturally it will depend on your overall goal. Keep in mind how the specific turbo size and design affect the power band and overall performance. For example you may get more top end power (greater boost) but have little low end power due to a long spool up time. Also there may not be too many choices that will fit the stock manifold (if you plan to use it) due to its uncommon flange type. If you change to a aftermarket tube type manifold with a more common flange, then there are lots of options. Another possibility if you keep the standard IHI turbo (and manifold) is either change the turbin (as GIK suggested), or change only the wheel inside the stock compressor housing. There are a couple of aftermarket billet wheels available for this unit. They are designed to offer a bit more output from the basically stock turbo. It is not difficult to rebuild the turbo, or to install a new wheel. Just have the shop balance it after.
Yes, the rubber hose goes in to the injectors bore, and injector WITH O-ring goes in to the hose. Volvo injectors do not have the upper mounting ring and metal bracket so I took those from the UT injectors. IMO it is a bad idea to reuse the plastic injector mount as the Volvo injector requires a bigger bore. By having bigger bores, the walls would be very thin and would most likely break (due to the pressure from O-ring). My solution with a hose eliminates that problem. Zoom in my first picture and you clearly see the difference between the injectors. The UT injector has no O-ring, it has a rubber gasket in the very bottom. Therefore it doesn't create a pressure on the plastic mount walls, it relies on the push down force from mounting ring/bracket.
 
By having bigger bores, the walls would be very thin and would most likely break
Now I get what you meant. I can see the difference in diameter. Just keep in mind there is quite a lot of pressure the injector mount has to deal with, both from the fuel and the cylinder compression; ironically many Bosch systems have almost as much fuel pressure as the cylinder's compression, and the two are working in opposite directions so the total force is very high.
It will be interesting to see what you come up with using these injectors. But I sort of wonder if it may be one of those things that becomes more difficulties and expense than just using what fits directly. However don't let that discourage you, I'm only thinking out loud. ;)
 
Now I get what you meant. I can see the difference in diameter. Just keep in mind there is quite a lot of pressure the injector mount has to deal with, both from the fuel and the cylinder compression; ironically many Bosch systems have almost as much fuel pressure as the cylinder's compression, and the two are working in opposite directions so the total force is very high.
It will be interesting to see what you come up with using these injectors. But I sort of wonder if it may be one of those things that becomes more difficulties and expense than just using what fits directly. However don't let that discourage you, I'm only thinking out loud. ;)

Jeff, I'm confused as to how cylinder compression affects port injectors. I can see where boost pressure acts against the injector mount, and the occasional back fire has to have a momentary shock load, but I don't know how compression pressure enters into this.
Am I misreading your post?
 
Gene, you are right, it really does not if the valves are working correctly. For some reason I was thinking about direct injection engines. So in this case it would be about the fuel pressure mainly. On the stock X FI system that is a relatively low pressure (~50psi?), but since we are talking about aftermarket FI systems it can be 100psi.
 
Last edited:
Feel free to download a data sheet that covers most Bosch Fuel Injectors (link further down). Original or upgraded injectors can be tricky to find for the X1/9 (and UT Mk1). But with the "Hose Mod" on manifold I wrote about earlier, in combination with an "Top O-ring to hose adapter" almost any EV1 style injector would work. There are of course also other factors to consider when choosing a new injector such as impedance, spray angle etc. and I think this Excel file can be a good help.

I also found a formula for dimensioning injectors for a specific application (HP):

A common value for gasoline/petrol engines is BSFC - Brake Specific Fuel Consumption
BSFC NA engine: 0,5
BSFC Supercharged engine: 0,6
BSFC Turbo charged engine: 0,65
If running E85 add 0,15
Recommended Injector utilization is 80% (0,8)

Formula:
(hp * BSFC) / (No. of injectors * utilization) = X lbs/h, then X*10,5=cc

I am aiming for 200hp with gas so:
(200 * 0,65) / (4*0,8)=40,625*10,5=427cc

427cc??!! That's a lot. On my little tiny 1.3l UT engine? Can this really be true? I am looking forward to hear what Speedy Fiat says about this.
So now to todays quiz. Based on the formula, what kind of Bosch EV1 injectors should I buy?
-I will do the "Hose Mod" and covert top O-ring to hose if necessary.
-The Hose Mod will move the injector 5-6mm further in to the manifold (so I assume a wider angle on spray pattern would be beneficial).
-My MaxxECU handles any impedance/resistance.

It seems like .xls files cannot be uploaded to the Forum so please download your own copy from my OneDrive area instead:
https://1drv.ms/x/s!AkRtY7j1Vtuhmq5On2W1QQSRKaobOQ?e=4qe2Tv
 
The numbers obtained from that formula seem high to me. Back when I went through everything it came out to around 210cc injectors for my project (around 130 HP, turbo X1/9 engine). Even when I daydreamed of having 150 HP it was around 250cc max. Unfortunately I do not recall the specific formulas and data that went into it, only the outcome. And lots of information I've come across seems to confirm it. I'll be interested to hear more details.

Edit: I recall that things like fuel pressure were also part of the computations.
 
Upgrading the turbo internals is a good way of keeping costs down. I used the following company www.turbotechnics.com to install better internals to increase performance internals. I was a bit skeptical about this as the standard set up was struggling at much over standard and I didn't think changing the internal components would make that much difference. However , it did, requiring less boost, creating far less lag, a much flatter power curve and lower intake temps.
We also swapped from the original flywheel sensor to a trigger wheel on the front pulley. An electronic boost control solenoid. It has forged pistons and rods. Changed to a coil pack from a distributor. Upgraded the knock and oil pressure sensors. Installed an inlet air temperature sensor. Upgraded the throttle position sensor. Lamda sensor in a bigger bore custom exhaust. Bigger injectors (260cc I think, I'll double check) which required a simple adaptor kit to fit. Ditched the air flow meter. Ditched the standard intercooler for a PWR charge cooler. This wasn't all fitted at once but incrementally over a few weeks and many dyno runs to overcome fueling, temperature and power curve issues.
Depending on what output your after you certainly don't need all the above, but the further you go the less the factory set-up can cope with it and so you are effectively developing an engine with a miniscule resource budget as compared to the original manufacturer
As is the often the case with my projects I start with much more enthusiasm than knowledge regarding how to do it and the costs involved, but then would I go ahead (and miss all the fun) if I knew all that in the first place? While making no great claims for my progress i think I'm now getting somewhere near on this one
 
the further you go the less the factory set-up can cope with it
Pretty much everything you described with your setup is exactly what I've come to understand after researching things. And it parallels what others have learned and developed as well. So I am trying to do much the same as I build my system. I've been rather fortunate to gain from the experiences of others (like yourself) and from access to some of the leading turbo experts at events like the SEMA show. I have been very impressed with their willingness to openly share their knowledge and experience.


Bigger injectors (260cc I think, I'll double check)
Please see if you can find your notes to confirm this. I'd like to hear if my estimated injector size is about right.


I am of the impression that one of the biggest challenges with a turbocharged engine in a X1/9 will be heat management. Given the amount of increased engine operating temps (internally) and increased engine bay air temp from the turbo (externally), in a vehicle design that already has limited heat management capability (mid-engine, tight engine bay, marginal cooling system). Requiring improvements/additions to the engine's cooling system (e.g. radiator, tubes, etc), the size of the intercooler, and external thermal control (things like heat shields, insulating materials, and air flow). I am trying everything possible in this regard, to the extent of sacrificing the rear trunk and opening up the bulkheads and rear taillight panel.
 
Germany is in EU so I do not need to go there. I can order car parts from all countries in EU without extra customs charges etc. But best would be to find something on Swedish junkyards. I've managed to fit a "standard" Volvo, Pegeout, Saab etc. injector to a UT Mk I (and X?) by using a rubber hose that fits exactly to the drilled hole on the inlet. I am not using the plastic adapter between the injector and inlet tube because I realized it would break. The UT/X injectors do not have an O-ring, they have a round gasket that seals by pressure from the injector mounting ring. I assume an O-ring would cause the plastic adapter to crack over time.
As you see the Volvo 240,740,940 injector to the left doesn't differ much from the UT injector to the right except the O-ring:
View attachment 25498

By adding a rubber hose that fits exactly to the hole on the inlet tube, with an inner diameter of 14mm, and reusing the rubber ring and mounting ring from UT it looks like this:
View attachment 25499
This is super tight and opens up for a lot of options. The upper part of the injector is still causing a problem but can easily be solved by the (overpriced) Australian converter/adapter mentioned in earlier posts.
(The picture above is just a test. I will clean it up, have a pair of tubes instead of washers ;-))

However, one thing in this setup is worrying me a little bit. The Volvo injector will be closer to the inlet compared to the UT injector:
Volvo:View attachment 25502 UT:View attachment 25503

I don't know if this will have an impact on spray pattern. To me it looks like the Volvo injector would be more efficient. It at least looks better? What is yor oppinion?
The Volvo 960 Turbo injectors would be my first choice for my application. They deliver 310-330cc/min and that should be good for the 200hp I am aiming for on my UT Mk1 engine.
I've also found a complete list of Bosch injectors. I will structure it in an Excel file and publish it later.

I've discussed a turbo upgrade with GIK Turbo Sweden, they are a Holset, Garrett and IHI representative. There is not much space for a bigger turbo, the alternator is very close to the downpipe. They offered me to rebuild the IHI VL3 with a bigger turbine which was quite costly (700$). Speedy Fiat, Did you upgrade the turbo? I would love to hear more about your mods.
I like You solution with Volvo injectors.
Also there is, I believe, cheaper adapters than ones from Australia and in EU, because electrician has already bought them for me.
will try to ask him tomorrow.
 
Upgrading the turbo internals is a good way of keeping costs down. I used the following company www.turbotechnics.com to install better internals to increase performance internals.
I just reviewed the linked website. Sounds like an impressive company. Please refresh my memory, are you still using the standard UT turbo but with upgrades, or do you have a different turbo unit plus the upgrades? And what internal upgrades did they do; impeller wheel, porting, different housing, or ??? Thanks.
 
Regarding injectors and adapting different types. Although I choose to retain the stock type of injectors (hose tops) that directly fit the manifold and Fiat fuel rail, I did look into some options that have the 'push-in' tops rather than hoses. As I understand there are two basic approaches to the upper adaptation; a complete fuel rail replacement (I think that's what Bjorn pictured earlier from Australia), or individual adaptor pieces that convert each injector from push-on to hose to utilize the stock fuel rail. There seemed to be many different brands with different prices, but I did not find a lot of difference between the two approaches. Each approach has benefits and drawbacks, but both sounded like they would work well. And the total cost to go either direction appeared to come out about the same once everything needed was included. Although I did not pursue this very extensively, I think it might come down to your planned performance level. If your system will require a lot more total fuel flow to support the desired power, then using replacement custom fuel rails may be better. On the other hand if you are planning a milder street turbo and the stock fuel rail will supply enough fuel flow, then I'd go with the individual top adapters.

For my plans the stock rail will be sufficient. However I have done a couple of minor improvements to help it. The fittings on both ends (inlet and return) are replaced with larger ones (mostly to accommodate the type of fittings needed rather than the flow requirement), the fuel lines (hoses and hardlines) are increased size, the fuel pump and filters are larger high output versions from other vehicles, plus I replaced the fuel regulator with a aftermarket adjustable version. If you really want to increase the fuel flow with the stock rail there are two more things you can do. The inlet end has a significant reduction in diameter where the fitting is. You can cut off the stock end to eliminate that reduction and weld on a larger fitting. Or you can supply the fuel feed to BOTH ends of the rail (removing the stock regulator) and add a new return port plus regulator in the middle (where the two halves of the rail join). I'm sure there are other (better) solutions, these are just things I came across.
 
I like You solution with Volvo injectors.
Also there is, I believe, cheaper adapters than ones from Australia and in EU, because electrician has already bought them for me.
will try to ask him tomorrow.
Yes, cheaper (4.93 EUR + VAT) adapters are available from Finland http://www.finjector.com. They have a wide range of fuel injector related products. Seem to be very serious.
If you found them cheaper elsewhere please let me know.
 
Upgrading the turbo internals is a good way of keeping costs down. I used the following company www.turbotechnics.com to install better internals to increase performance internals. I was a bit skeptical about this as the standard set up was struggling at much over standard and I didn't think changing the internal components would make that much difference. However , it did, requiring less boost, creating far less lag, a much flatter power curve and lower intake temps.
We also swapped from the original flywheel sensor to a trigger wheel on the front pulley. An electronic boost control solenoid. It has forged pistons and rods. Changed to a coil pack from a distributor. Upgraded the knock and oil pressure sensors. Installed an inlet air temperature sensor. Upgraded the throttle position sensor. Lamda sensor in a bigger bore custom exhaust. Bigger injectors (260cc I think, I'll double check) which required a simple adaptor kit to fit. Ditched the air flow meter. Ditched the standard intercooler for a PWR charge cooler. This wasn't all fitted at once but incrementally over a few weeks and many dyno runs to overcome fueling, temperature and power curve issues.
Depending on what output your after you certainly don't need all the above, but the further you go the less the factory set-up can cope with it and so you are effectively developing an engine with a miniscule resource budget as compared to the original manufacturer
As is the often the case with my projects I start with much more enthusiasm than knowledge regarding how to do it and the costs involved, but then would I go ahead (and miss all the fun) if I knew all that in the first place? While making no great claims for my progress i think I'm now getting somewhere near on this one
Thanks for sharing. Very useful information as I am preparing for my build. The MaxxECU allows me to do my build much like the way you did it.
I also think upgrading the IHI VL3 would be a good idea, but costly. GIK Turbo want 700EUR for such operation. I can buy a brand new high perf Garrett to a Volvo for that money here. I would like to hear more about your boost controller solenoid as the IHI doesn't look very standard on the exhaust side. I assume the WG spring (0.84 bar) should be removed and the bell replaced by the solenoid in someway?
I've been in contact with a couple of UT guys in UK to discuss injectors. They are running 450 cc injectors, you have 260 cc?! To test fitting I currently have Volvo 960 Turbo (2,3l, 4cyl. 165hp) 334 cc injectors, so 260 cc injectors on a 200hp UT seem a little bit small? It would be a lot easier to find 260cc injectors than 450 cc injectors so please verify that the smaller would be sufficient and where to find the "adapter kit" if my "Hose mod" on EV1 type injectors shouldn work out as expected.
 
I see they also have bottom adaptors for injectors. Could any of them work for the injectors you are considering?

Regarding selection of the injector size, it seems very common for guys to get really high flow rate units - much larger than their needed requirement. I think much of this is not understanding that bigger is not better. The ECU can throttle back the pulse rate/duration, etc to reduce output, but only to an extent. At lower RPM's (e.g low speed running or idle), that will get below its ability to provide the right mixture (if the injector is too large), resulting in poor running. Therefore I would not necessarily assume what others have is correct or best.

Boost control can be handled by the ECU in conjunction with a solenoid (example below). The solenoid will regulate the vacuum/pressure signal to the wastegate (actuator in the case of the UT IHI turbo) to control the cycling of the gate and boost. The small (and very short) vacuum/pressure hose on the turbo is spliced to install the solenoid in line.

Sample boost control solenoid:
mac3port.jpg


Where the solenoid is installed on the UT turbo, between the arrows:
Mk1 UT engine view - Copy.jpg


Example of how it works:
3-port_install_0.jpg
 
Jeff

it matters "where" in the engine cycle the fuel is injected........

there are wastegate cansiters that can "push and pull" .....and 4 port solenoids.
 
it matters "where" in the engine cycle the fuel is injected.
Referring to injector size I assume?


there are wastegate cansiters that can "push and pull"
Which is why I said "vacuum/pressure" line, trying to be general. :) And in the specific case of the standard UT turbo being discussed, a 3-way solenoid is correct (no second port on the other side of the canister's diaphragm). ;)
 
I see they also have bottom adaptors for injectors. Could any of them work for the injectors you are considering?

Regarding selection of the injector size, it seems very common for guys to get really high flow rate units - much larger than their needed requirement.

Boost control can be handled by the ECU in conjunction with a solenoid
Yes, Finjector also have adapters. Some to allow a Bosch injector to fit in various Japanese cars, some to adjust the lenght of the injector, and some for people making their own manifolds. The latter is more or less an aluminun tube to be welded on the inlet. In our case my "hose mod" removes the need for adapter and welding. Adapter or hose would work for EV1 (rubber mount) but probably not for EV6 injectors. EV6 would likely pop up due to internal pressure as a straight fuelrail cannot be used on X and UT Mk1 engines. We are stuck with stock fuel rail and EV1 injectors.

I sure lack clear directions for chosing injectors. Some say 450cc others say 260. I've found Punto GT/UT Mk2 Stage 3 (250hp) injectors, also used in Volvo 850T; EV1 339cc, so they would fit with mod. They would be affordable and easy to find here in Volvoland. That's something in between, but I will wait for Speedy Fiat specs before I decide.

Thanks for the explanation for how ECU, Boost Controller and Waste Gate play together. -I am a newbie in turboing so I'm still learning. One more question though. The WG spring allows 0.84 bar if I remember correct. Must it be replaced for more boost or will Boost Controller and ECU handle this?
 
I imagine if those 339cc injectors are good for a Punto GT stage 3, then they should be more than enough for your Mk1 build. There are several improvements with the Mk2/PGT set up compared to the Mk1 UT that would require a larger injector on that application (basically it is more efficient) - especially for a stage 3 built PGT. So I can't see how a modified Mk1 could exceed it. But that is just my impression.

As far as experience with turboing, I am also a newbie. But I have been extensively researching it for almost 3 years, and specifically for the UT. So I am trying to share what I've learned. But I would certainly value the input from those with more experience. So keep that in mind with my opinions.

I received some good info about wastegate spring pressures (and blowoff valve springs) from a couple of top experts for building turbo systems. They suggest to start by identifying your target boost (maximum PSI/bar). Then select a WG spring rate that is 50% of that (assuming you are using a ECU/3-way solenoid boost controller setup). 100% if not boost control. The reason is the controller can then adjust the pressure from there. It is different if you have a wastegate (actuator) with two vacuum/pressure attachments; one above and one below the diaphragm. That can use a 4-way solenoid that can increase AND decrease the boost levels much more, therefore a completely different static spring rate is used (softer if I recall). I purchased a aftermarket actuator the has a selection of springs plus is adjustable for spring rate (has a threaded fitting over the spring seat). It also allows the length of the actuator rod to be adjusted to assure proper seating/sealing of the wastegate and full articulation.

The recommended spring rate is different for blowoff valves. The suggestion here is to start with a spring that is somewhere between your engine's idle vacuum reading and the lower range of your target boost level. The recommended range is wider than with a WG because some trial testing is necessary to dial it in. The idea is to use the lowest spring pressure that will seal the valve and not "float" when alternating between acceleration and deceleration ('blipping' the throttle). This is where an adjustable BOV (similar to the adjustable WG with a threaded fitting) is really useful to help get it set.
 
I had an interesting discussion with the owner of BJP Race in Sweden when I was looking for injectors. It turned out that he built 3 UT Mk1 engines 15 years ago. With big valves and ported head and Mitsubishi turbos. They produced 240 hp with stock internals. Whats even more fun, they are still working. Peter Björk (shop owner) meant that 400cc injectors are necessary to obtain this level. He also ment that modern injectors perform much better than legacy ones, so even a bigger injector would work also on lower revs and load. He recommended a Standard SMP 440cc that would fit (EV1) with *hose mod* and top adapter. The price is reasonable so I will go for those.
Now I am going to eat the next part of the elephant:
I think a Liquid to Air Inter Cooler would be best on our mid-engine cars. A lot of heat are generated and not much space available in the engine compartment. I've been looking at PWR and AVT IC's but they are very expensive compared to the IC's on Ebay, Ali Express etc. I've been warned about China made IC's; bad quality, poor cooling, pressure drop... But after watching this I am not really sure if I will spend 3-4 times more money to have a branded IC/Heat Exchanger.
Have a look a these videos. The first one is a "scientific test" the second a "On Road test".
 
For a power level of 240HP, 400cc injectors sounds reasonable compared to what I've read about. Not that the HP level is the best measurement to judge by, but it falls in line with the other things I've heard. So 400cc isn't unreasonable compared to what I found for a SOHC goal roughly half that power level with 200cc injectors. By the way, 240HP may almost be too much for the X to be able to put to the ground.

As for Chinese products. I do not believe in the general notion that all China products are junk. In fact some of the best products in the world come from China, and some of the worst come from countries like America or Germany. And vise versa for all of them. In other words, there really are no valid blanket statements that can be made about the country of origin when it comes to today's global market. The truth is many of the well known brand-name products from other countries are in fact manufactured for them in China. Most countries allow companies to legally say "made in XXX" on items actually produced elsewhere. Just legal jumbo. So you really cannot tell where a particular item is really made, or what it's actual quality level is just by where it is sold from or who is selling it. But as I said, that does not make things good or bad, it is a case by case (or item by item) issue. And price definitely does not dictate quality as many people seem to believe. That is only common sense in today's marketplace.
 
Back
Top