91firebird350

Hey crew.

I have a very out there question and i was wondering if someone can help me with it.

Its seems that the TPI motor is to an extent not very modification friendly unless you go carb'd or get into writing code for a new PROM. The basics are nice to add on such as exhaust, runners, intake and other things, but to go farther its seems you have to get do programing.
I like my car and it is very responsive for 245/345 numbers.

Here is my interest.
My friend has a stock 5.0 Stang 225/300 and was curious to know why a small motor with close power ratings and a different air set up ( mass air vs speed dens ) takes to modifications a lot easier then our cars.
I have not seen very many people get into chips or computer with there 5.0 mustang unless it involves stand alone management units. I know that the stangs do have a computer aswell.

My friend just redid his whole motor, cam, heads, exhaust, headers ect and done. Why dont our cars have that luxury.? Arent Chevy 350's supose to be one of the easiest motors to work on or are these the exception to the rule.?

Now i do know price wise, Chevy is hands down cheaper then a Ford to build.

Can someone shed some light on this.

rough

From what ive read on tuning, you can throw all the parts you want at a car, and it can run without tunning, but when you want to suck every last hp/tq out of those new mods, tunning becomes your best friend.

Maybe ford has better ECM's, i dont know, Id rather not have my car "Found on Road Dead" so i don't drive fords.

Im sure one of the Tuner gurus can enlighten more information on this subject.

OldCelica

I know nothing about specifics to Ford engines so maybe I'm not the best one to answer this...... That being said here is my 2 cents:

350s are very economical to build. The main reason for this is that (For the most part. Except for 400 SBs) SBC parts are interchangeable form one engine to the other. This cuts down on manufacturing costs because after market companies do not have to design specific parts for a 305 vs 350 for example. The savings get passed down to the consumer. That is the main reason that SBC engines are cheaper to build.

As far as ease of building goes I'm guessing that if no mods to the computer are needed on the Ford engines then the computer dynamically configures itself and therefore compensates for cam, head, injector, timing, and displacement changes. I doubt that is the case. I could be wrong here though.

As far as I know anytime a computer is involved with controlling how the engine runs on any vehicle it will need to be reprogrammed to get peak performance after swapping out parts that change how the engine runs. For most (If not all) OBDII vehicles I believe that you can change the programming of the computer on the fly using a laptop and interface software. This GREATLY makes it easier to program the computer for mods. Our vehicles are OBDI unfortunately and I don't think that there is ANY way to adjust on the fly.

Most of this are my observations and not necessarily fact so if anything I said was incorrect please correct me.

DJ_SirG

good answers guy's.
The bottom line is, with all youre friend has done to his Ford is great he too will have the same prob as you with programing. Mods work well by allone but better with friends and better with programing.

TPI

Celica had it best IMO, 8bit OBDI has it's limits & is obsolete.

There is OBDII conversion for our cars, Im not sure how much more
beneficial it is in the long run.. but, the one big lure to OBDII is
Sequential fire as compared to a batch fire system of old..

Would be awesome on a TPI motor.. and OBDII provides just that.

This is probably not the reason why Mustangs are more mod friendly,
but it is reason enough to believe TPI could be that much better.

OldCelica

Also side note on the Ford 5.0L specifically. When comparing to our 305ci engines you need to take into account that the bore is bigger and stroke is shorter on the Ford 5.0. This allows for the fitting of bigger valves in the heads to gain more flow then we can get out of a 305. More flow = more HP.

I know the original question was about comparing a 350 to a 5.0L. I thought it may be more fair to compare engines that are (more or less) the same displacement.

90c350

You are comparing Speed Density Vs Maf systems as well. The Maf system will beable to compensate more for mods do to it being able to read the amount of extra airflow entering the engine. Speed density will not reconize an extra amount of fuel is needed when mods are done. It will have to be retuned for the extra air and fuel needed. Its just how the two systems work. The Ford Maf will still need to be retuned as well to get the best power or if you are going overkill with heads/cam etc. Just my 2c's

skyhigh4by

iTrader: (1)

If I remember correctly one of the most important mods for 86-88 stangs was to convert from speed density to MAF. Mods wouldnt do much for them until they made that swap.

91firebird350

So am i correct to assume then that TPI motors that where MAF prior to speed den. that they took to modification better. Its just interesting how it all goes together.

IROCtheThird

iTrader: (15)

If your asking what I think then yes, all MPFI 3rd gens from 85-89 were MAF, 90-92 were MAP. Yes MAF will compensate better, but not fully, especially when you start to get into bigger lift cams etc...