Auto TPI on marine Chevy 350

[AdamB]

I'm in the process of switching my old TBI chevy 5.7 truck motor to the TPI style fuel injection. A cheap and easy process which will net 30 to 40 more ponies... <br /><br />I know you can't put a auto carb on a marine engine, but how about tune port injection?<br /><br />The mid 80's TPI provided plenty of low and mid range torque which should work on a marine engine with the proper ECM and chip...<br /><br />Thoughts??

 

[tommays]

Re: Auto TPI on marine Chevy 350

you cant use any auto parts on a boat that use electric or are part of the fuel system is more or less a good guide line<br /><br />most auto electric parts are not do not have the correct spark shielding or good enough water proofing<br /><br />there are a lot of rules about fuel systems also<br /><br />most of the rules are ment to prevent fuel vapor explosiens eather by not sparking or not spilling fuel<br /><br /><br />tommays

 

[LubeDude]

Re: Auto TPI on marine Chevy 350

Tommays is right, but you allready have TBI, so I see no reason that you cant do it. K&N has a Coast guard approved filter for the TPI. You may want to contact Mercury Marine, as they have been selling engines wit the TPI on them for a number of years.<br /><br /> Any modification you do like this is entirly your responsability for you and your passengers, run your bilge fans, and dont cut corners on instalation.

 

[seahorse5]

Re: Auto TPI on marine Chevy 350

Marine fuel parts also are required by Federal Law to be fire-resistant. They have to withstand a 2 1/2 minute direct flame without leakage. Clamps and hoses, etc. are also required to meet these specs. Automotive items probably do not meet these guidelines as both Merc and Volvo have to use specialty items. Even the GM Marine TBI is comepletly different than the automotive version.

 

[AdamB]

Re: Auto TPI on marine Chevy 350

LubeDude,<br /><br />I meant I was switching my TBI in my truck to TPI, which made me wonder why I couldn't switch my 4 barrel carbed Chevy 350 marine engine to auto TPI also. The sytems are cheap in the junk yards now a days, like $150-500 depending on how clean and compete they area. <br /><br />But to everyone else that answered, thanks for your input. I guess it takes more than just being a back yard mechanic (who can do almost anything to autos) to be a smart backyard boat mechanic.

 

[seahorse5]

Re: Auto TPI on marine Chevy 350

Originally posted by AdamB:<br /> <br /> I guess it takes more than just being a back yard mechanic (who can do almost anything to autos) to be a smart backyard boat mechanic.

Besides being mechanically oriented, you have to know the laws because boat engines are in an enclosed space where fumes can accumulate and be ignited by a spark. In a car, the engine is open to the air, and any leaking fuel drips to the ground and evaporates.<br /><br />There are standards and procedures that have to be met.<br /><br />Aircraft engines also have to adhere to a set of regulations, and the mechanics have to be licensed.

 

[summit1]

Re: Auto TPI on marine Chevy 350

And don't worry about just yourself exploding on a boat ramp or on the water....I don't want my wife or kid to be exploded by someone using the wrong parts on a boat. <br /><br />I don't want to be a jerk here, but on too many threads (Tom can attest to this) no one seems to care about anyone but themselves when deciding to do some of the things they do. Remember, if you blow yourself up in your garage, hopefully that is your business, but when you blow yourself up on a boat ramp in a marina, it becomes everyone elses. Be smart and do the right thing.

 

[tommays]

Re: Auto TPI on marine Chevy 350

easy now people adam was asking what parts could be used BEFORE he did anything and i am sure now that he has been made aware of the problems of useing auto parts he wont<br /><br />tommays

 

[summit1]

Re: Auto TPI on marine Chevy 350

I meant no ill will with my post. I apologize if anyone took it that way. I meant to make the point that we should look at things from other perspectives. You are right Tom. <br /><br />It is frusterating to hear guys say skrew it, I am going to do it anyway...kind of like the antifreeze deal and letting it dump from the boat in the lake. It's that mentality that hurts others. I was just pointing out 'don't be that guy'

 

[AdamB]

Re: Auto TPI on marine Chevy 350

No offense taken guys, thanks and I will definitely make sure my boat complies with all laws, rules and regs.

 

[Peter J Fraser]

Re: Auto TPI on marine Chevy 350

AdamB,<br />If you took the care to use 'Packard' or 'Deutches' electrical connectors on all your wiring you would be OK. These are the same items that are used in a lot of marine applications already and are widely used on automotive as well.<br />With the correct spec cable you have most potential problems licked.<br /><br />Peter

 

[seahorse5]

Re: Auto TPI on marine Chevy 350

AdamB,<br /><br />Here a few sites that show some of the laws concerning electrical and fuel systems on a boat.<br /><br /> http://www.uscgboating.org/regulations/boatbuilder/downloads/electrical.pdf <br /><br /> http://www.uscgboating.org/regulations/boatbuilder/downloads/fuelsystem.pdf

 

[AdamB]

Re: Auto TPI on marine Chevy 350

Thanks, I'll look into it.<br /><br />Do you guys think I can get more torque out of my motor using 14X19 prop converting to TPI, or by switching to different 4 barrel setup?? Right now my hole shot sucks (especially pulling skiers), but am already over-revving with the 14X19

 

[tommays]

Re: Auto TPI on marine Chevy 350

adam<br />to be honest your boat should jumping out of the water with that motor a 5.7 on a 20 ft boat should fly<br /><br />my 3.0 sounds like its putting out more power right know i think you still need to see if the boat is water loged or something in the motor i would still make sure the tack is reading corectly<br /><br />tommays

 

[AdamB]

Re: Auto TPI on marine Chevy 350

Quickly read over both links provided, I see where they mention ignition protected items, such as coil etc. USCG regs also apply to carbs, such as they need flame arrestor etc. However, I still don't see anything that would prohibit auto fuel injection... as long as the originally protected items remained the same. K&N even makes a USCG approved filter for the TPI. THe TPI injectors spray directly into intake manifold, unlike the carbs and TBI units which have external spray. PS, wow, that's a lot of reading!! There is a lot of specific references to marine carbs having to pass marine tests, but nothing for TPI's...

 

[tommays]

Re: Auto TPI on marine Chevy 350

it has to due with the wires and the controls that run the TBI as well as the fuel pressure reg system and the need for the oil pressure saftey to shut down the TBI system if the motor stops unexpectely and it goes on and on<br /><br />basicly its more to due with the non-marine electric controls and pumps that run the TBI<br /><br />when i left the trade i started working on land based controls for enclosed spaces with fuel vapors and there is not any part on a marine engine that would be allowed to be used even at your local gas pump <br /><br />as strict as the CG regs seam they are really pretty mild and easy to meet compared to land and the NEC regs<br /><br />tommays

 

[jimmythekid]

Re: Auto TPI on marine Chevy 350

where would you put the oxygen sensors?

 

[jimmythekid]

Re: Auto TPI on marine Chevy 350

seems you would have to have different manifolds cause the o2 sensors cannot get wet

 

[Buttanic]

Re: Auto TPI on marine Chevy 350

You do not need oxygen sensors to run electronic fuel injection. Their primary purpose is to provide a optimized air/fuel ratio to minimize emissions. All that is really needed to run the system is a trottle position sensor(tps) and manifold absolute pressure sensor(map).

 

[highaltitude]

Re: Auto TPI on marine Chevy 350

the concern i would have would be ecm compatibility. i believe the automotive tpi setup uses a mass air flow sensor. the marine application does not. the sensor will not hold up to the abuse. a new ecm could make it a non-economical investment