This is the sensible approach considering whatever stand-alone you buy isn’t going to have a 348 base map. If this were a more popular car you might be able to get away with both, but for ours. No way.
Aren't the stock injectors 18lb/hr? Don't think that would support 350hp at stock fuel pressure. (maybe 300 or so maxed out)
Need to check but pretty sure that's at 3.0 bar, at 3.4 should work. I know back on the 355 ITB effort they were able to add 20% more fuel above 4500 rpm and 10% below that.
You don't need a base map. You just need to know how to tune. While there are easy pathways if you have a corvette you can still start from nothing and do well. There are lots of resources out there like DIYautotune and HPtuners that will support you while there are others like Motec who say they help but in reality not very much. I would only consider motec after a good understanding of tuning. I would go to DIY or HP with zero knowledge but just a desire.
I think you’re missing the point. I was agreeing that it makes sense to get the motor running right in stock form on an new ecu *before* making physical changes to the engine. That’s all.
Correct, any more significant horsepower from the F119 needs bigger injectors. When I had my injectors flow tested after they were serviced, they all flowed 184cc at 30psi. That cannot support 400hp. I doubt at 100% duty cycle they would, which is not good for injectors to be doing. The AFR on my dyno runs was 12-12.5:1, if you open up and give it significantly more air, its going to run dangerously lean, its going to need more fuel and more timing.... You might get away with 13-13.5, but that is starting to get a bit on the lean side. Its a real black hole getting into this sort of thing, and a vortex of exponential cost, which is why despite my interest and motivation to actually do this to my car, I have not done it, its an expensive exercise.....not to mention the time. 30 more horsepower, you might get that, but I would not do it without running it on the dyno so you can monitor AFR, you might end up with a very lean engine and eventually cause damage to the engine...
I think 3.8 bar and 24 lb injectors at 90% according to math at least. I do know the Spider had 320 with stock injectors and No Doubt with Plugzit was able to add 20% more fuel to that. Pretty sure the LM car has stock injectors and FPR.
Pretty sure factory GM LS1 injectors will work. I have it in my notes somewhere, but they can be found from 22lb and up cheap.
The point is not to make a 355, its about projects on the car of which I have had many. This is just another in feasibility phase.
Mustang fox body 24 lb also as far as I know. Check your notes get back to me as this all helps. To be clear this is a months months months long effort part time. Still need to order the mill and lathe, just finishing up work shop now that engine is rebuilt and running as a perfect baseline, it make's a good candidate car. And spare TB just arrived.
You don't need to buy a throttle body "from" something else, you can just buy them, generic, various manufacturers. I was looking at some the other day, you can just specify what you want it to have and what size, no brainer for a project like this. Also don't need injectors "from" something else either, just specify what you want and buy 'em.... Yes, 320hp from the 119H is more than just pushing more fuel at it. It has bigger throttle bodies, and a larger plenum, from this, and my own dyno runs they definitely needed both more fuel and air, and also remember the 119H is a higher compression ratio engine too, more volumetric efficiency... I'm not trying to put you off or criticize, just sharing what I know from my experience messing with high performance engines most of my adult life, making mistakes and learning from the process. I'm an advocate for eeking a little more power from the 348. It just may not be as simple as it seems, 10% power increase is not "that" noticeable, but maybe its enough to liven it up a bit.
Yep I spent almost a decade tuning turbo motors so its no so much of desire and no skills as much as itnis a problem to be solved in small increments, also why I know 400 hp is a whole other problem than 330-350 ish, need new EM and a few cans of worms for that. Spider has 20 hp more than TS, additional 10 would be 30 over TS and 10 over spider. If nothing will keep my brain busy. I am making my own tb actually. What's the fun in buying one. Pretty sure unichip piggybacks are an easier option than new ecus btw.
Right, sucking that mich air without em will not work the ecu can. It can not compensate that much, a bit on either side to be adaptive but not 30% more fuel without map changes for sure. Did you notice effects of it missing at lower rpm or did you keep it intact under there?
Well I would be, rather than speculating on what the various models "should" have, I would get it on a dyno and get a baseline. You know what Ferrari are like, it depends on what day of the week it is, what fuel they used to dyno test/tune or how they feel at the time as to what horsepower rating the give their engines sometimes. Like I mentioned, the models which have 320hp (supposedly) have the F119H, higher compression and the bigger throttle bodies, larger plenum....the compression being the key element there. Who knows the cam profile might be different? Ah cool, making your own throttle bodies is awesome, then you can dial it in to exactly what you want, nice! I looked into Eproms to remap my car, and although it would be cheaper, its a massive PIA, they are not as straight forward as it seems to flash, but not impossible. Plus, you're starting to mess with 30+ year old electronics, these motronics are not going to last forever. I would find it very hard to believe the 355 2.7 cars have the same/similar fuel/ignition map as the 348, totally different engines as you know, but I don't know so I am only speculating..... Where did you get that information from?
I have the Motronic 2.7 355 chip hex extract, few folks have the spider extract, waiting for a copy. A guy out here compared them back in 2012 btw. There still are ways to turn them into 3d maps. When I get them both I will do that. 100% sure you can get to 350 with a slight chip flash and slightly bigger injectors. Flow is usually stated at 3 bar or so the bosch ones are, with 3.8 bar they are actually almost 21 lb with 19.4 lb at 3 bar from memory, 3 bar is what almost 44 lb.
Very interesting, and I agree with your 350 theory, more RPM would help too, 8000 rpm limit would be better, if the engine can breathe it will rev higher which will help to produce more power (in theory)..
Easy to get into a can of worms, next thing you know we are talking cam profiles and so forth..... I go around all these things in my head when I am thinking about making more power and then I end up doing nothing on the basis that its going to end up being a massive and rather expensive exercise...
Its called Shipwrights' disease. One you know its a thing you know to avoid it. 330-350 tops is where I am at. Should be very doable.
Despite what is said I believe I need an injector 10=12% bigger ar 3 bar, single spray nozzle, close to 21 degree angle, same form factor as OEM. The TS is at 3.4 bar so no fpr upgrade for TS needed. 10% bigger at 3.4 bar is more like 13% bigger in the TS and 15% bigger in Spider with napkin math. A huge injector will cause issues with motronic even after a chip updates An inector sized for that need with 80= 85% duty will work getter than 40lb injectors just sh*tting fuel ino the cylinders. Plus they need to be avaliable not rare like hens teeth. Well see...
Lots of info on injectors out here that are not "wrong" but are not "right" either, they lack context. A X flow injector can actually be +/- a huge % depending on FP for example. If a 300hp engine needs 21 lb injectors... how do the 18/19 lb 348 injectors work? It does work... so maybe it a math thing. Injectors are rated at 3 bar for 1 thing and some cleaners/rebuilders flow test them at much less like 2 bar so always check the bar.. Anyhow... The 348 injectors actually flow 200 cc at 3 bar FPR, which is 19lb/hr but .... the 348 TS has 3.4 bar, not 3.0 bar FPR. So, for a V8 engine making 300hp at the crank, at 3 bar FPR, and an 80% duty cycle one needs 21 lb injectors. The 348 injector at 3.4 (TS FPR) bar is 21 lb rounding. The 320 hp variants needs 2 lb more or 23 lb injectors and the Spider needs somewhere in between. The 348 injector at 3.8 bar (Spider FPR - 6 psi more) meets that need as well. Not a lot of room for overhead so to meet over head needs it dips into the duty cycle I'm sure. Anyhow the injectors for the 348 are not undersized they are correct but just. Feel free to check my math but CLEARLY the TS and Spider run quite well with the injectors even on the track. So they can not be undersized. They however are not sized for 330 hp although I know few cars out here that actually do that power with stock injectors but you can bet they are near 100%. So search for a mythical 10%-15% not 50% more injector, measured at 3 bar, with 348 specs continues.
