increase horsepower using 1993 Beretta computer (Page 1/2)
sledcaddie SEP 02, 08:07 PM
So, this guy tells me a story about some guy from Michigan, who used the computer box out of a 1993 Chevy Beretta to increase horsepower in his 88 Gt to 250. He stated that the process involved changing the stock EGR to an electronic one, and disconnecting the cold-start injector. Anybody ever heard of this before? Is it somewhat legit or just snake oil? Thanks for any input.
olejoedad SEP 02, 08:12 PM
Snake oil.
gregr75 SEP 02, 08:34 PM
if it sounds too good to be true, it probably is.
Dennis LaGrua SEP 02, 08:59 PM
Shortly after the Fiero V6 was built, a racer by the name of Herb Adams decided to dyno test the engines. He tried making numerous changes to the program timing and fueling. After trying many combinations no power increase was made by altering the chip program. Herb reported that the GM engineers did their job well. What did work was the porting of the restrictive exhaust manifold that gave an extra 5-7 free horsepower.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

Mike in Sydney SEP 02, 09:00 PM

quote
Originally posted by sledcaddie:

So, this guy tells me a story about some guy from Michigan, who used the computer box out of a 1993 Chevy Beretta to increase horsepower in his 88 Gt to 250. He stated that the process involved changing the stock EGR to an electronic one, and disconnecting the cold-start injector. Anybody ever heard of this before? Is it somewhat legit or just snake oil? Thanks for any input.



Snake oil? More like BS. If it was possible, the members of this forum would be all over it.

250HP is 110GHP more than stock. You might be able to do it with a 110 shot of nitrous - once. After that...?

I'm hard pressed to understand why changing the EGR to a electronic unit (how would that work, anyway) or disabling the cold start valve which if I understand it correctly only operates during the cranking cycle when the engine temp is below 95°.
lou_dias SEP 02, 10:26 PM
That's known as the 7730 ECM conversion. I'm using the NA$T1 code mask with supports up to 8400 rpm.
I currently make 211 rwhp using a heavier drivetrain than stock, so hypothetically I am making 250 hp.
It's a 3.5L iron head engine. It's still not running perfect so I do expect to make more power. Also, I'm still on 93 octane with octane booster. Once I go E85 it should make closer to 240rwhp.

So it's not impossible, just requires a lot of unmentioned investment.
Notorio SEP 02, 11:43 PM
Without looking for my old bookmarks, or searching, doesn't the 7730 conversion yield a smoother idle and provision for a knock sensor?? Of course one can't do this in California because the digital EGR would fail the visual test.
82-T/A [At Work] SEP 03, 07:34 AM

quote
Originally posted by sledcaddie:

So, this guy tells me a story about some guy from Michigan, who used the computer box out of a 1993 Chevy Beretta to increase horsepower in his 88 Gt to 250. He stated that the process involved changing the stock EGR to an electronic one, and disconnecting the cold-start injector. Anybody ever heard of this before? Is it somewhat legit or just snake oil? Thanks for any input.




On any otherwise stock motor, you could gain a couple of horsepower by having custom programming to optimize the fuel mapping... but you wouldn't really gain any peak horsepower since things like EGR (if I'm not mistaken) are shut off during wide open throttle anyway. I think 93 was the last year for MPFI, and they went to SFI the year after, or maybe SFI started in 1993. You gain better around-town performance, but again... no increase in peak HP. Going with a newer ECM though should improve some drivability issues that tend to get exacerbated when the car gets older.

A brand new Fiero though never had hunting idle or hesitation at any RPM.
edfiero SEP 17, 01:59 PM

quote
Originally posted by Notorio:

Without looking for my old bookmarks, or searching, doesn't the 7730 conversion yield a smoother idle and provision for a knock sensor?? Of course one can't do this in California because the digital EGR would fail the visual test.



I am still amazed at California emission testing. Guys doing visual inspection today weren't even born when the Fiero was produced.
Would it be the end of the world if we stopped emission testing after a car hit 25 years old or something?
82-T/A [At Work] SEP 17, 02:32 PM

quote
Originally posted by edfiero:

I am still amazed at California emission testing. Guys doing visual inspection today weren't even born when the Fiero was produced.
Would it be the end of the world if we stopped emission testing after a car hit 25 years old or something?



I'm not an expert, but I think most states that do have emissions testing, likely have some rules that a car is less scrutinized once it reaches a certain point. Sometimes it's combined with other things like getting a classic car designation (which brings with it different / lower insurance premiums since you wouldn't be driving it as much).

But yeah... I'd imagine, if the car is meeting emissions requirements (tailpipe sniff), why do they care then if the original equipment is on there?