horsepower efi 300
 

Hey,

I was thinking about doing a rebuilt on my 300. It is a fuel injected motor (1988) and I was wanting to increase the power a little bit. Is there any way to achieve 200 hp and a good increase in torque on these motors without changing the computer? I know the heads are restrictive and swapping in a cam might be out of the picture because I remember reading some where that you have to get the ecm tuned. What I am wondering is there anyway to get another 25-30 hp ontop of the stock 170-175?

Stock is more likely 150-155HP
A stock truck 302 is only 180.

Headers, junking the cat, and rebuilding the engine may net you 160-170HP. The general concenssus around here is the EFI jobs are best left stock as the improvments are pricy and few.

If you are hardup for power, There are cams, programers, and intakes that will help out a bit.

i dont think they have a programmer for a speed density computer, do they?

if you want to make any real power from that truck you will pretty much have 3 choices...you can upgrade to Mega Squirt aftermarket ECU, you can upgrade to MAF (Mass Air Flow), or you can go back to carb

SD EFI systems will suport about 15% overall gain before the ECU self destructs, then youre in trouble...

200hp isnt all that hard...the mods that are gonna get you there are pretty much all internal engine mods...it can get a bit pricey

There was a guy on here that ran his EFI 300 on a dyno or something, and I don't remember his screen name, but he had the power numbers in his sig. I thought I remembered who it was, but they either changed their sig or I had the wrong person.

Anyway his truck made like 150 HP(I don't remember the exact HP number), and 272 TQ(that one is for sure right). Dynos only read at the rear wheels so 150 HP or around there, and 272 TQ is more than the engine itself is rated for. So he was probably running close to 200 HP, and 300 TQ. I think I asked him about it one time, and I don't remember what he told me, but I am pretty sure he told me one of his mods was electric fans.

Well that about as clear as mud I guess. I wish I could remember who it was.

Hi guys, I did exactly what Nicolass is looking for just one year back, I'll Explain what I did:

1° I got a stock rebuilt engine kit Sealed Power (Pistons .020", premium rings, valves, springs, crankshaft bearings .010", etc)

2° I got a Crame Cam 503905 + New Sealed Power lifter set.

3° 6 Motorcraft inyectors CM5041 + Variable fuel pressure regulator

4° 2.25 exhaust pipe + high flow muffler

No extra cooling was requiered, no tunners, programers, chips, nothing else.

My truck is F150,1995 4.9L + E4OD 4WD

ive been recently thinkin about using an electric fan. but i dont know what a good turn on temp would be. is 185degrees on/ 170 off good for the 300?i need to know so i know what relay kit i need for the install

Well the 300 is known to be cold blooded, and I think most EFI engines want to run hotter than carb engines anyway. I think 190 degrees is probably what the thermostat on the EFi 300 is anyway, at least the 351 I had was. I think you want the fan(s) to come on at or above the thermostat temperature so I would guess 210 degrees on, 180 or so off. I don't really know for sure though.

would this be acceptable?

Summit Racing SUM-890016 - Summit Racing® Electric Fan Thermostat Kits - Overview - SummitRacing.com

Should be quite adequate.

just to make sure im guessin my truck runs somewhere between there then? cool then ill be lookin at buyin a fan ive picked and this relay soon. is the install of the wiring any hard at all?

i cant remember but i think its 170 degrees the computer goes into loop mode...thats good...all engines run better warm...my truck in the winter sometimes wont make it to the N on the gauge and it acts gutless once it goes over that N it feels 10X better...i think it has something to do with the loop mode on the ECU

remember when buying electric fans the idea is for the fan to take up as much space on the rad as possible...2 small fans leaves more open space on the rad than one big fan does...the more air you can pull through the rad the better off you are...so the best way to go is one big fan rather than two small ones

hey javi2001 what kind of power did you push with that setup? im looking into a build and i want to do a MAF swap but if i cant i still want to build it just have to stay within the ECU limitations

Some have found that two fans from a Taurus fit and work fine.

im lookin at this one. could i do better? or will it do the job? the diameter is a good size and it has alot of cfm

Proform Parts 67016 - Proform Electric Fans - Overview - SummitRacing.com

this one actually looks better to me:

http://www.summitracing.com/parts/SUM-320718/?rtype=1

I have read just about everything on here about performance upgrades for the 300 efi, and I agree with what most everyone has to say except the fact that there is no chip or tune that can be done inexpensively to get around the air/fuel curves on the ecu. Well, I can honestly say that a friend of mine has purchased a product that allowed him to gain HP by doing the V8 TB swap, injector swap, and larger exhaust! He called me just the other day and told me that he produced 206hp/369ft lbs of torque with the upgrades he has done, and nothing is internal, just bolt ons and he has spent less than 500 bucks. Here is a link to the company he bought his product from. The x3 chip is what you need to look at, he said the only way to describe what it did for his truck was F@*KING amazing! Anyway here is the link:

X3 Performance Chip with O2 Sensor Control [40-50HP]

I can say that i wasnt there when he did the dyno pulls, so I cant verify this to be 100% true, but he has never lied to me about anything in the past so I take his word for it.

Oh, btw, I called this company today and asked about the x3 chip because they list it for the 90+ models, but they said that it will work on any efi truck with the 300, it just has to be efi. Im going to order this thing on friday and try to get to Dallas soon to do some dyno pulls. I just ordered the Magnaflow direct fit single cat set up and a single in/out 3 inch Flowmaster Force 2 setup, this should sound real nice on my 300, anyway if you guys want links to places to buy parts cheap let me know, Im only gonna have 400 bucks in a complete bolt on exhaust.

im sorry but i dont know if i can believe that