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Discussion Starter · #1 ·
So I picked up a complete Ramjet intake manifold and also included was the Mpfi 4 ecu and harness that the ramjet crate engine uses.
Currently running a dual plane gm perf intake and a sniper efi with hei and pulls really good.
Want to swap the ramjet intake for looks and more power hopefully.
So I have a few questions.
Can I simply plug and play the RJ intake and connect the mpfi 4 ecu and expect it to run my stock L31 cam decently? I Read that the mpfi 4 ecu is calibrated to the RJ"s cam profile etc. Specs on the stock L31 cam and Rj cam and not too far apart so maybe it will work?

I also want to go with coil on plug like an ls engine. I read that I can use a stock 0411 harness and plug and play with 24x reluctor. Need more details. I think I'm just going to go with a different cam but don't want to have my heads removed.
 

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the 'Duracell Project'
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i run a ramjet 350 in my 58 truk, it's a great plug n play motor, but expect no support from gm or this or any forum. the mefi4 is great when it's working fine, i had problems a couple years back and ended up throwing $1200 in parts at it. you'd think a gm crate motor would have gm support, nope. it's a marine motor, marinas can work on them, but insurance sort of dictates they can't work on any vehicle. my truk is currently running great and i think the ramjet is a great motor. just be aware of the restrictions. i wouldn't do what your planning, unless the motor was built to the exact specs of the ramjet 350.

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Discussion Starter · #3 ·
i run a ramjet 350 in my 58 truk, it's a great plug n play motor, but expect no support from gm or this or any forum. the mefi4 is great when it's working fine, i had problems a couple years back and ended up throwing $1200 in parts at it. you'd think a gm crate motor would have gm support, nope. it's a marine motor, marinas can work on them, but insurance sort of dictates they can't work on any vehicle. my truk is currently running great and i think the ramjet is a great motor. just be aware of the restrictions. i wouldn't do what your planning, unless the motor was built to the exact specs of the ramjet 350.

View attachment 618779
Yeah I
i run a ramjet 350 in my 58 truk, it's a great plug n play motor, but expect no support from gm or this or any forum. the mefi4 is great when it's working fine, i had problems a couple years back and ended up throwing $1200 in parts at it. you'd think a gm crate motor would have gm support, nope. it's a marine motor, marinas can work on them, but insurance sort of dictates they can't work on any vehicle. my truk is currently running great and i think the ramjet is a great motor. just be aware of the restrictions. i wouldn't do what your planning, unless the motor was built to the exact specs of the ramjet 350.

View attachment 618779
Ok so the harness and mpfi 4 are out of the question. But I can use still use the ramjet intake with another ecu and harness correct. What would be the best option? 0411 ecu and a harness from an 96-00 l31 truck? dizzy from an l31 also? Anybody looking to buy an mpfi 4 system? haha
 

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Discussion Starter · #5 ·
Was thinking of just buying a gm ramjet cam and running the mpfi 4 ecu and harness . Seems like the best option since I already have it might as well use what I have. A ramjet 350 is just a l31 with truck cam correct so should be pplug and play correct.
 

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Discussion Starter · #6 ·
Was looking over the ramjet manual and saw that it needs a 24 x reluctor ring to run and also saw that it needs a vss? I'm running a t56 without the gear on my output shaft for the vss. Can I do without a vss on this setup amd run good. H ow would this affect my setup. I think the vortec 350 comes with a 4x reluctor ring I would need to swap out is this correct can anyone confirm? What else am I missing
 

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Discussion Starter · #7 ·
Got a few questions for my swap. My plan is the ramjet intake on top of my L31 with an lt4 hotcam. I picked up a harness and 0411 off an 02 express van that I'm trying to use for the swap going into my 92 z28. Wondering if everybody uses the fusebox that comes with the harness or you guys remove it or what. Sorry for the noob question. Also got a t56 and wondering if I can remove all auto trans related pins? What would be the best program to tune this setup? I was looking at Hp tuners but whats the word on the street? Can I remove all egr and ac related pins?I Won't be runnig ac or egr or anything not needed. First time tuner help me out.
 

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Was looking over the ramjet manual and saw that it needs a 24 x reluctor ring to run and also saw that it needs a vss?
ramjet does not have a reluctor ring, just a standard distributor and a standard balancer
the manual was bastardized from a late 90s gm truck manual and has a lot of wrong information in it
no vss needed either unless you have cruise control like 58truk
 

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This being a basic multi-port F.I. why not go with a simple Megasquirt to run it? Something like a MS 2 will batch fire the injectors, run an idle step motor, dizzy and T.P.S. Good news is that you can tune it yourself without a high priced software.
 

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Discussion Starter · #10 ·
This being a basic multi-port F.I. why not go with a simple Megasquirt to run it? Something like a MS 2 will batch fire the injectors, run an idle step motor, dizzy and T.P.S. Good news is that you can tune it yourself without a high priced software.
[/QUOTEDo you
This being a basic multi-port F.I. why not go with a simple Megasquirt to run it? Something like a MS 2 will batch fire the injectors, run an idle step motor, dizzy and T.P.S. Good news is that you can tune it yourself without a high priced software.
Do you have a link for the MS 2 system? Reason I was trying to use the 0411 ecu is because everyone says its better because of the sequential fuel injection and the ability to use the vortec dizzy and crank sensor. But I read that MS2 can also control the vortec dizzy and run a maf and crank sensor as well. I'm using a harness off an 02 express van and am trying to eliminate certain wires I wont be using. What program is used with MS 2 to tune?? how cheap ?
 

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Discussion Starter · #12 · (Edited)
Got it to run. All sensors are hooked up except the o2 sensors. Only thing I did to get it to start was disable VATS. Got a few questions. Not sure if I'm supposed to use the MAF? I'm running the stock Ramjet injectors, can't remember specs but same injs in the lt1, Do I have to adjust a setting for injectors? Pulled a plug and it was kinda wet. So I started it up and checked for codes and I'm getting the p1345 for the cam offset, and another one for crank/cam correlation which I think is one in the same. So I found the cam offset PID. When I start it up the cam offset is at 0.30 I believe. Idleing around 7-800 rpm. Has to be at 0 correct? The way I (set timing) was find tdc on 1, balancer mark lined up with mark on timing cover, then stab dizzy pointing at the little 8. BIG problem I have is the vortec dizzy has no space to move behind the Ramjet intake, literally it's trapped in the same position blocked in by the fpr and fuel rail inlet. Rotor points at 8, and cap goes on in that fixed position. No space to adjust. What can be done. Anyway I can find how much 0.30 offset is and stab the dizzy in a certain way retarded or advanced to try to set the offset thing. Also wondering if anyone has a 24x reluctor so I can go CNP if this doesn't work out. I do have timing tape on my balancer if that can help.
Thought about something else also. Ramjet 350 fpr is set to 45 psi correct. Haven't verified on my setup.. Stock ramjet injectors I'm running are rated at 19.lb, stock vortec spider injectors are also 19 lb but pressure is 58 psi? the flow rate on the express van is set at 23.1. I used a injector calculator and put in my pressure and got 16.1 flow rate. Is this correct ?
 

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Can't address your fuel pressures or delivery rate but can say the ramjet is designed for 45lbs of pressure. With regard to your cam offset retard. If you are doing it correctly the scanner will show you degrees. Not sure where you are getting 0.3. In order to remove the 1345 you must be within +-2 of zero. My engine never wanted to be 0 it had to be negative.

You are going to have to be able to rotate the distributor while the engine is running to get it set correctly.

I'm also curious how you are using the OEM PCM that requires a MAF sensor.
 

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Discussion Starter · #14 ·
Can't address your fuel pressures or delivery rate but can say the ramjet is designed for 45lbs of pressure. With regard to your cam offset retard. If you are doing it correctly the scanner will show you degrees. Not sure where you are getting 0.3. In order to remove the 1345 you must be within +-2 of zero. My engine never wanted to be 0 it had to be negative.

You are going to have to be able to rotate the distributor while the engine is running to get it set correctly.

I'm also curious how you are using the OEM PCM that requires a MAF sensor.
Have been fixing up my setup one bit at a time. Had to move my inlet line because the dizzy was hitting the line not letting me set my offset. Got my offset down to almost 0. Tons of space now. I'm running the 0411 with maf delete. Only runnimg in sd . Getting lots of help. Still a work in progress but it runs great. Still buttoning up a few things.
 

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Discussion Starter · #15 ·
Have been fixing up my setup one bit at a time. Had to move my inlet line because the dizzy was hitting the line not letting me set my offset. Got my offset down to almost 0. I also was getting a p01345 for cam sensor performance but I believe I was getting inteference, I had my harness routed right along the dizzy ignition wires. Tons of space now. I'm running the 0411 with maf delete. Only running in sd . Getting lots of help. Still a work in progress but it runs great. Still buttoning up a few things.
 
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