PDA

View Full Version : Please post some pictures of GT 40 engines



Hagman
02-02-2012, 02:05 AM
I’ve been doing research on installing EFI on the comp with a stock ford intake. The wrecking yard here has a Bronco that I can get all of the parts I need for $250. Fast EFI has a retro fit system that will hook up to stock ford parts but a o2 censer needs to be installed into the wet exhaust. The censer needs to be kept dry & get hot. Has anyone out there installed a o2 censer it to wet exhaust?
From what I understand a stock marine GT 40 engines are running a open lope efi system . This system has no o2 censer for real time calibration. This efi system changes air /fuel mixture by temp, map & throttle only .

86 century
02-02-2012, 08:56 PM
Yup the marine efi doesnt have an o2.

An auto efi will not run properly without the o2 it will stay in open loop all the time.

another way to go could be holly proinjection or one of the after market setups.

cadunkle
02-03-2012, 05:02 PM
Just stick with a carb, they're better. Simple, reliable, efficient. EFI doesn't really offer anything significant except mroe complexity expense and chance of leaving you stranded.

Hagman
02-09-2012, 10:50 AM
I know there has been a couple of threads on here about making the change to EFI. I’ve been reading this forum for a about 2 years & haven’t heard of anyone that’s made the change over. All of the carb guys say its not worth the money & trouble for the benefits and there right. I still want to install an EFI system . I’ve had my comp for 25 years 1700 hrs made all kinds of update & modifications that weren’t really need GT40 heads, PP exct . We8713ll I’m going to make the change if I don’t like it I’ll just change back. I was hoping for some support for you guys.
I have found a wrecked bronco that I can get all of the parts I need for $250. That includes distributor ,wiring, computer all of the censers everything but the fuel pump & a heated O2 censer. Or there a couple of companies that make aftermarket retro fit kits that will hook up to stock ford EFI intake manifold . Please give me some positive input,,, technical support and maybe some pictures of GT40 engines that have been direst up.
Hagman

Jetlink
02-09-2012, 02:20 PM
Hagman, correct me if I read your post above incorrectly but, you did the GT-40 head upgrade and do not feel that it was worth it in the long run? Reason I ask is that I had the opportunity to compare my non-GT-40 comp to another one that had the upgrade and it blew me away and I am now considering it. As for the EFI, that is your decision to make, if you can make it work then go for it.

86 century
02-11-2012, 01:26 AM
If you want to use the bronco fuel injection your gana haft to find a way to get the o2 in the exhaust before the riser where the water comes in.

Does your bronco doner have an o2 on both banks(i cant remember been a long time).

Have you thought of a way to get the o2's in the exhuast neer the riser before the water comes in.
Would be a bit of a chore to drill the mani's and get them resealed

Hagman
02-11-2012, 02:02 PM
When I went though my engine rebuild I made several changes at the same time . Manifold, GT40 heads. I had the heads C C’ed ,Cam, balancing , new carb and a 13x12.5 4 blade prop. The cam was a mistake. I ski at 34mph about 3200rpm that was right where the cam was changing power, we had a hard time holding a steady speed. However it worked grate for bare footing. I tried making changes to compensate all summer, in the end the cam went back to stock. I do know after the changes the boat is quicker out of the hole and it’s easer to hold a steady speed. There is know one here with a boat like mine to compare with. The guy I ski with the most has a 05 Prostar 190 and the comp comet pretty close ..If it’s because of the heads I don’t know. The balancing is what made the biggest different . To do it over the $1100 I spent on the heads would have went toward a prefect pass first.

Hagman
02-11-2012, 02:36 PM
If you want to use the bronco fuel injection your gana haft to find a way to get the o2 in the exhaust before the riser where the water comes in.

Does your bronco doner have an o2 on both banks(i cant remember been a long time).

Have you thought of a way to get the o2's in the exhuast neer the riser before the water comes in.
Would be a bit of a chore to drill the mani's and get them resealed
There87358736 is a couple of ways to install a o2 s sensor it to wet exhaust. Howel engine products has a fitting but there is some custom machine work involve . There is a adapter plate that is install between the manifolds. Here is a pic of one.

86 century
02-12-2012, 05:48 PM
That should do it.

I think the fords of that era are mass air flow so it should adapt to your eng fairly well.
You are going to need a way to fool the computer into thinking the down stream o2 are still there.
You should be able to do that by taping into your o2's and put a resistor in the line to make it think the cats are still there.

The only othe thing I can think of is the distributor not being a marine modle.
Myself I dont see it being any worse than points.

Will the intake from the donor fit you eng.
Does the block have the port for knock sensor.

Next thing would be the fuel pump and return line.
You could probably tap into tge fill line with your return line.

Don't take this as trying to tell why it wont work. Im just thinking of all the things you will run into along the way.

Hagman
02-12-2012, 10:38 PM
That should do it.

I think the fords of that era are mass air flow so it should adapt to your eng fairly well.
You are going to need a way to fool the computer into thinking the down stream o2 are still there.
You should be able to do that by taping into your o2's and put a resistor in the line to make it think the cats are still there.

The only othe thing I can think of is the distributor not being a marine modle.
Myself I dont see it being any worse than points.

Will the intake from the donor fit you eng.
Does the block have the port for knock sensor.

Next thing would be the fuel pump and return line.
You could probably tap into tge fill line with your return line.

Don't take this as trying to tell why it wont work. Im just thinking of all the things you will run into along the way.Thanks for your input. I haven’t taken the time to go check out donor Bronco the weather has been not so good here. And the owner is not in a hurry. All I know is that it’s a role over with 70,000 miles and it a 351 W. I’ll check all of your ??? I have the o2 part covered unless someone comes up with a better idea.
I‘m open to all suggestions.

Credo184
05-18-2013, 12:21 AM
Hagman I was wondering how the conversion is going I am very interested in doing the same swap. From what I have read going MPFI does not help on the top end; the boat's low RPM torque and manners are much improved. I was told that start up and warm up is a breeze with MPFI. I would not recommend just installing an unmodified car ECU. The load levels on a road going car are different from a boat. I think factory automotive fuel maps will make your boat dangerously lean at lower RPM's; on a car the fuel maps take very little feed back from the O2 sensors until it reaches operating temp appox 185. On a raw water boat that is to high and needs to be adjusted to 160 so the boat goes in to closed loop at that temp. I have found an adaptor to run a truck or van lower intake and mate it with a 5.0 upper.
http://www.bcbroncos.com/store/product_info.php?cPath=131_108&products_id=1059 (http://www.bcbroncos.com/store/product_info.php? cPath=131_108&products_id=1059)
I have been considering modifying a foxbody mustang harness with a microsquirt so these parameters can be set.