Nicely done! Congratulations!

 

Personally I think a 2bbl TBI is a better choice for a 1,9 engine, I doubt that a 1bbl TBI will make much more hp than a 1bbl carb. But the 1bbl TBI sounds just right for an ohv.

 

Actually the 1 bbl 1100 Sniper is rated to flow 175HP if you believe Holley. I will tell you that the 2 bbl 2300 Sniper I have on my 2.6L engine is arguably too much. The idle is not consistent and the acceleration from cracking open the plates is quite highly ramped. I've altered my pushrod geometry to make it smoother but it needs a serious amount of exponential curve added to make it right. I would love to try the 1100 on my 2.6L engine but too much work to play with right now. Now if the 2300 was a progressive TB like the 32/36 Weber I think it would work much better!

 

FWIW.. I like the idea too.. and was originally going to go that route with my manifold design.

But then one issue with the Holley 1100 crept up.. availability. ( Currently they do have an expected ship date of late April/May 2023 )

Also Steve H. the Red GT you see in my pictures. Had his fail on him and he sent it back for repair.. 3 months later he finally got it back and they hadnt fixed the main problem. He is still waiting..

I do love the concept and it would make things a lot easier, especially on mild motors. But QC and availability are what lead me down the other path.

 

Do you have a fuel return line back to the tank?

 

Great question! Yes, I forgot to mention that. We did run the return line back to the rear drivers side vent port. As previously mentioned in other EFI threads, those vent ports have a small orifice built into the tube so you need to drill it out to allow adequate flow for the return and avoid too much pressure buildup. Drilling that out can be tricky with tank in the car.

 

32mm throttle plate ? Sounds a bit small, the stock 19N etc Solex 35PDSI has a 35mm one.

 

The Autolite 1100 is 1.2" at least on all the data I could find it could be better. But not by much..

 

That is pretty cool! What are you going to use for the air cleaner?

 

Here's a Youtube link for the initial start and engine run on this setup.

 

Here's a Youtube link for the initial start and engine run on this setup.

Sounds good.. !

 

Thanks Charles. The obvious drawback to this versus what you are doing is limitation on ultimate power for bigger CIH engines, lack of multiport fuel tuning and no 4 channel spark control. The Sniper can control timing which I've played with on my 2300 setup but went back to stock Opel dizzy. Only one channel that controls the coil firing and you still need to use the dizzy to "distribute" the spark.

 

The Sniper can control timing which I've played with on my 2300 setup but went back to stock Opel dizzy.

Curious why you went back to the stock distributor? I've got a Sniper 1100 to install on an air cooled VW beetle engine. I have a Bosch 009 distributor for it which I can lock out and use a Pertronix I module according to your wiring diagram for your 2300 experiment. Did this not work out nicely for you?

 

great stuff! thank you so much for making the effort to post a video!

 

Great job.
The size is plenty. I have a bit of experience with fish carbs which your system reminds me of.
The main mod you now need (being a performance single barrel ) is to prevent refection from a flat bottom under the TB.

I remember Bob has a suitable mod with a 90deg divider at the base of the plenum that would do wonders.
Great job

 

Went hunting found this.

Porting intake

I was looking through the forums, and came across several mentions of porting the intake manifold in order to improve hp. I didn't find any mention of what the best method of doing this is. Is this something that can be done by an amatuer? (I'm fairly handy with tools, but no mech. genuis). I...

www.opelgt.com

You can just bolt a piece in the bottom of the plenum.

 

Here's a video of the first drive with the Sniper 1100.

Weather is hit and miss here in Ohio. We don't drive our Opels when they dump a bunch of salt on the roads so we have to wait until some good rains to clean the roads off!

 

Weather is hit and miss here in Ohio

Thats for damn sure! In the morning the furnace is on, by noon you need the a/c and it's raining and by sundown it's frickin snowing. And that is in May.....LOL.

 

Gil and I both think the Sniper 1100 is suited ideally for the stock to mild CIH engine and offers yet another option for a simple EFI conversion. Expect to see these adapter kits from OPGTS in the near future.

Just curious how insanely expensive is this conversion going to be?

 

I think you could do the whole conversion for around $1300 including pump, lines and Sniper.

 

Also, keep in mind that you could use a returnless Edelbrock fuel pump system, like I use, and not have to come up with a surge tank or run a return line to the tank, just a small vent line to the tank that doesn't require enlarging a tank vent outlet and you also don't get the "toilet running all the time" sound from the fuel constantly getting pumped back to the tank.

 

This would all be new to me but has my curiosity. Not necessarily my wallet for just show car driving though.

 

Lot's of CFM to HP calculators on google if you search for them and the conversion varies obviously depending on the efficiency of your engine design. But the majority of calculators yield lower numbers than most people think. Here's one calculator that indicates a N/A engine developing 100 HP only requires roughly 70 cfm. A 300 hp v8 engine only requires about 150 cfm according to motortrend.com. I'm no expert so I'm only offering what I've found thus far.

 

The Sniper rpm input is the low voltage side. The Pertonix is a Hall Effect sensor, same as your setup that simply provides the rpm pulse to the ECU. No difference at all. The sniper provides a separate coil trigger signal that runs through a coil driver device (nothing but an IGBT transistor circuit, and sold separately of course). All coils no matter what ECU or otherwise require a higher current coil driving device. As a matter of fact, most modern coils are what are called "smart coils" whereas the IGBT driver circuit is built into the Coil on Plug (CoP) or Coils near Plug (CnP) arrangement.

Granted, modifying the Opel dizzy to lock out the advance takes a little work but it's not that hard to do. So if yours is turn key then it does save some time and effort for those not willing to modify their stock dizzy.

 

The sniper provides a separate coil trigger signal that runs through a coil driver device (nothing but an IGBT transistor circuit, and sold separately of course).

This I think this the electrical difference ( excuse my ignorance of that end of the EFI system.. ) but the coil driver device is part of my system out of the box. The distributor has a pull up resistor ( thus the 3 wires and not two wires a Pertronix has ) and uses a Bosch ICM to drive the coils.

Per the Microsquirt directions :

Pertronix on Opel Dizzy :

My Distributor

The ICM can change to which version you want and let tuner studio do its work

If someone wants to go with one of the more exotic systems this can work..

The way it is "As is".. there is a way for the computer to see #1 and all 4.

Anyway, not sure this will work for the 1100.. but its what does make mine a bit different compared to a locked-out Opel Dizzy and Pertronix and it will work with a Microsquirt or Speeduino.

 

Charles, a quick tutorial on pull-up resistors and keep in mind I'm a EE: Practically all digital signal generators whether triggers, logic gates or otherwise generally require a pull-up resistor off the output transistor. Otherwise the signal will float (i.e. the term open collector). The Pertronix has three connections just like any other Hall effect sensor. The third wire is not a wire but the grounding plate when you mount the unit in the dizzy. So you still have plus, negative, and the signal wire. The pull-up resistor is internal and built into the output of the hall effect sensor and that circuit drives the internal IGBT which then drives the coil negative side. It is NOT an open collector circuit on the output of the Pertronix. Properly wired into the Sniper, it works fine as a digital trigger for the ECU RPM input with no additional circuitry at all.

But in all honesty, this thread is merely about the install of the Sniper 1100 on a stock engine. It is not intended to be a discussion about the pros and cons of your distributor versus any others. Suggest starting another thread on dizzy options for ECU applications.

 

Mike,

I see you are the foremost expert of things called Holley, in regards to GT's. Is there a particular model you feel is best for a 2.4?

 

I think, in the end, the best thing to do is to give your car to a dyno tuner. Get it running at a minimally acceptable level and if you want things to be more perfect, give it to a tuning place. Unfortunately, there's far too many guys who think it's more fun to figure it all out themselves. Those are the guys that post never ending threads about their latest tweak.

I was almost there with my SSD manifold/2 injector/twin throttle body experiment, but a weird quirk in the shape of the manifold or the squirting force of the injectors caused all the fuel to excessively favor #4 cylinder, causing it to chronically flood. But I could tell that the power I was seeking was there, but just out of reach. The solution is to have the manifold modded with 4 injectors at the ports, which is what I'm having done. But, just in case that fails for some reason, I'm also having a custom "normal" manifold made or maybe I'll use Charlie's if it tests out okay.

My plan is to first install a normal manifold, take everyone's advice and tweak it to run acceptably, then take it to a tuner and see if they can get more perfection out of it. That will happen on my yellow project car. Once it's running fine and dandy, then I'll consider removing the stock 2.4 Motronic FI and install the modded SSD manifold on my GTX car. I'll use the charts and settings from the yellow car's normal manifold set up to get it running. Since both engines are stock and identical, they should both run pretty much the same.

As far as sequential injection, well, I'll have the capability to do that, but it will be something that I will do at a much later date. First get both engines running with the simpler batch fire injection, then decide to turn into an engine weenie and try to sequential inject.

I really don't want to spend the remaining years of my life endlessly dicking around with Opel engines. I don't think it's fun or interesting in the slightest to play with engines. I'm into all the other mods you can do to cars.

And I also like to just start my car and go for a drive and not spend one second thinking about how my engine is running.

 

I’m considering putting this setup on a 2.4 with 38 Weber on it now. I am seeing a lot of doubt that it is big enough for anything over a mild 2.0. The unit states around 175hp and I can’t help to think that most people are highly exaggerating their HP numbers and don’t really know what they got. So best I’ve seen on a stock 2.4 is 123bhp. I have a bit bigger pistons that are higher compression, but the 1mm thick head gasket to drop it down, and an Isky Combo cam.. . So I don’t think we are talking anything more than 140-150HP. Though I’m seeing that most feel the 2300 Sniper is too much. Though one member cut down his 100 pound injectors to 48 pound, so basically would be the same poundage as the 1100, which is a single 100 injector.

 

I firmly believe that it will work.. but no different than a 38 or a 32/36 with a 2.4L it will limit total power and top end due to limited and restricted airflow.

The 2300 I think on a 2.4L would be fine as well but you will need to tune it on a dyno.

In most cases (i.e. not racing and those that drive the car on the trailer and off and go to cars and coffee..) either will work OK, given the tunable nature of the sniper.

If the dyno on my 2.5L with a slightly bigger OR-77 cam, taller rods, and similar pistons is any indication, header, and the GoinEFI manifold. One caveat is I did have a Low port head vs a High port so that could affect it some as well. I would say we are probably roughly the same compression.

That said I was 122 HP at rear wheels ( roughly 140 ) - So, I would still say 140-150 HP is probably high. Your probably closer to 115-125

As It comes down to air flow.. ( assuming your modified distributor and my ignition table are close to equal thats another issue ).

I know Bob will correct me, as engine dynamics airflow vs how airflow works in a HVAC system can be different.

That said physics is physics and being a HVAC engineer and having designed my own intake.. I can tell you at least the "base" numbers we have here can tell a tale.

So if you interpolate the data and note that the GoinEFI intake is the only one intake there that was identical between the runs. So it gives an anchor to the data, that and the bare open ports.

1.9L vs 2.4L on my intake there is a 10 CFM bump on the 2.4L head around the 025 to .030 range :

104-110 CFM at 0.35​

108-122 CFM at 0.45 lift​

​

Roughly a 4-10% increase​

High Port Head Bare vs the Low Port Head - There is a 0 CFM at valve opening to 20 CFM difference in the bare head on peak..

So in General terms..

High port heads flow up to 20% better to peak of the cam lobe ( All things being equal and no porting, etc.. )

Apply that to a Stock Down draft intake on a low port head ( we didn't have a downdraft for the high port ) and even the Holley modified one by Bob was at best 95-98 thats a 10-20% loss

Some comparison on the charts, do a little algebra.. and you will see

IN GENERAL:

High Port = 0 (0-0.25 valve opening ) to 20% improvement at peak vs Low Port Head​

​

Down draft = -10% to -30% loss of air flow vs EFI and Side Draft intakes.​

So on a Downdraft at best your flowing 10% lower than a EFI or Side Draft intake at 0-0.25 for airflow

So sticking to a downdraft intake with a Holley, it will still run, but will be a limiting factor on top end power and pulling off the line..

That said, with your mods, and a downdraft, and such you're probably looking at about 90-110HP rear wheels.. (115 to 125bhp)

Which is still 15-25% better than stock and as no one has to tell you it's VERY noticeable.

So budget, ease of install, and the final expectation and all come into play.

Enemy of the great is the perfect, enemy of the good is the great..

The GoinEFI intake was initially designed to fit... | Facebook

 

So after talking with Gil at Opel GT Source, we are both on the same page that even on a hopped up 2.4 this 1100 would be more than adequate. Even Gil mentions unless you are running the Autobahn at 136mph, it will be just fine if not perfectly sized for a 2.4. A little research showed one guy downsized the 2 barrel Sniper injectors to less than that of the 1 barrel to make it work better. So today I received the kit for the 1100 installation on an Opel all models. I will say I was very impressed with the quality and the materials used to make this happen. There is a factory air cleaner adapter, that is cast and then machined. I thought it was still the 3D printed parts. No it is all machined parts, the thermostat housing is new and now has a boss that is tapped for the CTS and they even include a drill bit so you don’t have to go hunting for tools. Very complete, although I’ll need to get an O2 sensor bung. I have a 2.4 in the shop that would be a good candidate for the conversion, so I’ll probably start with it.

 

Yep.. as I said it will work. Just as a 38DGAS will work.. They are made for larger motors after all.

The limitation is the intake.. and that will bottle neck the top end power and throttle response. Probably only truly noticeable on a Dyno. Because it will still probably be better than the original setup. Love to see what it does on the dyno actually.

 

Sunmit Racing right now has a sale on the 1100 EFI for 96.09 off. That’s a heck of a deal if you are considering this setup

 

Thanks Keith on those comments on the kit! Forrest and I worked and refined that conversion kit over last summer to get it right. Looking forward to seeing how it performs on your hopped up 2.4L!
I may still try this on my hopped up 2.6L but ultimately might go the injector swap route just so I can maintain the higher air flow capability.

 

Here is the Sniper kit you will receive. I wasn’t sure if it included an O2 sensor bung, but it does have one, with a plate.

 

Here is the Sniper kit you will receive. I wasn’t sure if it included an O2 sensor bung, but it does have one, with a plate.

JHMO but I have done several EFI installs and I highly recommend welding in the O2 bung as the plates don't seal well and the O2 sensor is one of the primary sources of frustration folks will have with the efi install if it is reading incorrectly due to leaks or the placement of the O2 sensor.