Intake

[1987cp]

hehe... you want to make power with central fuel injection? Get a Holley Commander 950 TBI system!

[nitroracer]

Well Gm had good luck with teh TBI so Im sure there is the potential to hot-rod a cfi. And some people just like to be different. I think we all fall into that category for driving/modding the cars we do and not being old as dirt.

[OVERKILL]

hehe... you want to make power with central fuel injection? Get a Holley Commander 950 TBI system!

Speaking of that kit, I have one in my basement that I'm putting on a 4.3L GM in a boat in the next few months............

[OVERKILL]

Well Gm had good luck with teh TBI so Im sure there is the potential to hot-rod a cfi. And some people just like to be different. I think we all fall into that category for driving/modding the cars we do and not being old as dirt.

They had good luck with it? Because as I recall, TBI was the reason that the GM engines were absolute TURDS compared to their TPI counterparts and why there was a switch to SEFI on the Vortec motors which, combined with the improved heads, made for a HUGE improvement in power output.

Remember, in 1987, the 302 in the Mustang made 225HP, whilst the 350 TPI in the Camaro made 220HP. That is the BETTER of the two induction offerings from GM.............Yet makes 5HP less than the crap-headed 302 that is giving up 48ci to it...............

[gadget73]

The CFI manifold was horrible, and the heads also kind of sucked, but in properly running form, a 1985 cfi motor makes like 5 hp more than a 1986 SEFI motor. I'm really convinced that with a better set of heads, even stock e7 heads, good exhaust, and an aftermarket intake with a 4v to 2v adapter the CFI system has the potential to be a decent performer. It won't be a super screamer, but it would do OK. The CFI unit also necks down internally. Boring the neck out should result in better airflow, which also should be good for a bit od power. If you stick in a slightly more agressive cam, maybe a truck cam, it would probably rock and roll.

[grandpaslincoln]

Hell I'm convinced, if you think it should be done, then it shall!

[interceptor1985]

NO CFI!!!! Go Carbed or EFI and I see that your going carbed more power to ya

[Tiggie]

The CFI manifold was horrible, and the heads also kind of sucked, but in properly running form, a 1985 cfi motor makes like 5 hp more than a 1986 SEFI motor. I'm really convinced that with a better set of heads, even stock e7 heads, good exhaust, and an aftermarket intake with a 4v to 2v adapter the CFI system has the potential to be a decent performer. It won't be a super screamer, but it would do OK. The CFI unit also necks down internally. Boring the neck out should result in better airflow, which also should be good for a bit od power. If you stick in a slightly more agressive cam, maybe a truck cam, it would probably rock and roll.

The only problem I see is that the ECM would completely freak with the better air flow from the heads and intake and cam swap. I suppose you could do it with an aftermarket ECM.

[1987cp]

Remember, in 1987, the 302 in the Mustang made 225HP, whilst the 350 TPI in the Camaro made 220HP. That is the BETTER of the two induction offerings from GM.............Yet makes 5HP less than the crap-headed 302 that is giving up 48ci to it...............

Didn't the TPI 350 (L98, I think they called it?) have various things holding it back? Like small intake runners, restrictive exhaust, not such great heads, and that sort of thing? I also want to say TPI's switched to a speed-density system somewhere around 1990, accompanied (I think) by a bump in output. Someone correct me if I'm way out in left field.

[1987cp]

The only problem I see is that the ECM would completely freak with the better air flow from the heads and intake and cam swap. I suppose you could do it with an aftermarket ECM.

Right, wouldn't you'd need entire new fuel and timing maps at the very least? And then change it every time something's upgraded, not to mention the modifications to the throttle bodies and buying bigger injectors and that sort of thing, plus the trouble of integrating everything so all the pieces talk to each other properly. I'm not convinced it would be cost-effective just to end up with a cobbled-together injection system, but I could well be wrong.

[Mercmarquis]

megasquirt CFI lol

[OVERKILL]

Didn't the TPI 350 (L98, I think they called it?) have various things holding it back? Like small intake runners, restrictive exhaust, not such great heads, and that sort of thing? I also want to say TPI's switched to a speed-density system somewhere around 1990, accompanied (I think) by a bump in output. Someone correct me if I'm way out in left field.

The Mustang engine had all the exact same restrictions, a crappy intake, welfare heads, crappy headers.....etc.

And yes, somewhere around 90, GM "fixed" some of the issues to try and gain some power output. Of course Ford then slapped a set of GT40's on the same 'ol 302, put in a slightly milder cam with some 1.7's, and put on a better intake and we had the Cobra motor, which still made more power than GM's offering........ With less displacement.

It wasn't that GM's offering didn't have potential; It did. But GM's solution has always been to simply throw more cubes at it instead of trying to irk more power out of what's there.

When they finally departed from the antiquated small block to the LS1, there was a nice big jump in power output..... ~320HP. Of course Ford was making the same power with the DOHC 4.6L....... 281CI vs 346CI....... The LS1 was somewhat under-rated though (like the '00 Cobra R) and so ACTUAL power output was a bit more than the 320 flywheel quoted.......... The added displacement meant that the engine didn't have to scream as high to make that power and ultimately, was the reason that the Camaro was faster than the Mustang, even when both had the same rated power output.

[gadget73]

Right, wouldn't you'd need entire new fuel and timing maps at the very least? And then change it every time something's upgraded, not to mention the modifications to the throttle bodies and buying bigger injectors and that sort of thing, plus the trouble of integrating everything so all the pieces talk to each other properly. I'm not convinced it would be cost-effective just to end up with a cobbled-together injection system, but I could well be wrong.

Phayzer was running E7 heads on his CFI motor in his 84 for a while and it did OK. To get the most potential out of it, you'd need to fatten up the fuel mix but even without doing that, it would still perform better than stock just by removing some of those restrictions. Unfortunately as far as I'm aware, the CFI computer is not tweecable, so you're pretty much on your own with it. Possibly a batch fire truck ECM could be plugged in and tuned though. They both have just 2 injector drivers so it might just work.

Also I never suggested it would be cost effective, only that it would probably work, even if not as well as a carb. You could certainly megasquirt it though. It might be an interesting experiment just to see what could be gotten out of it. Unfortunately its got the potential to become real expensive for little gains. It might be something I'd like to play with if I can get the parts for close to free and I was planning on doing a carb swap or something anyway. If you're already doing a carb swap, but still have functional CFI, it wouldn't be all that much to slap the CFI unit on there and just give it a run to see what it does. If it fails, just yank it and toss the carb on there and call it a day.

[85crownHPP]

I talked to one of the guys that souped up his CFI LTD (fox body) - he put the bored-out CFI on top of a fresh bored HO roller block with nice heads and the 4bbl intake w/ 2bbly adaptor and he said it went 13's.... this was with gears and exhaust and other goodies...
This was using the "HO CFI" computer found in 84-84 CFI AOD mustangs and the few LTD LX's that got the HO CFI

He said the main setback was that the two biggest injectors you can get for it only squirted X amount of gas and by the laws of physics was only good for something like upto 280 HP or something. Still not too shabby...

[1987cp]

This was using the "HO CFI" computer found in 84-84 CFI AOD mustangs and the few LTD LX's that got the HO CFI

Interesting. I should have figured the Fox-body CFI systems would have a lot more potential! How'd it do at part-throttle on the street?