clintonvillian
Famous Member
I wanted to start a new thread as the other was cluttered with what ifs … My apologies, but I think I am slowly starting to iron out a few things and wanted to keep this thread strictly looking at the M112 build.
As stated previously I'd ideally like 300 HP and 400 ft-lbs. But if I am sinking this kind of money into it, why stop there....so I would like the option of increasing the boost and maybe going higher. BUT IT HAS TO BE RELIABLE.
Here is what I have:
-87 4.9L
-The head completed: 2.02 Intake, 1.72 Exhaust, 1.72 Rockers, and a CNC Head Port.
-C5AE 240 no hole rods
-Custom sheet metal intake and a Clifford Intake
-Dynomax Headers
-T-5 3.35 1st, 1.93 2nd, 1.29 3rd, 1.00 4th, .68 5th
-2.78:1 Rearend
-Eaton M112 with 2.5:1 drive ratio (I can and may need to go to a larger pulley on the blower as discussed in previous threads).
Discussion/Questions:
1. I have decided 100% on a Holley EFI system (Megasquirt is ruled out). I have not decided on using the HP or Sniper unit yet. I want to discuss each option below.
2. As listed above I have already purchased remanufactured 240 rods with ARP studs, peened and polished. Will these handle the stated power, where's the cut off? or should I sell them and go for the Compstar Rods
3. I have decided to run a water/methanol injection system and for go any type of intercooler. In normal driving I wont be in the boost that much, mainly just once in awhile showing off for other car guys.
4. According to FTF in another post, the Felpro #1024 is about the best Head Gasket out there. What PSI do you think this will hold up to? OR will I need to go to copper and an O-ring (again it is a daily driver so I don't want a leaky head gasket).
5. I have a normal nodular cast crank, will it hold?
6. Which side of the motor should I mount the Supercharger on. Personally I like the drivers side. It just fits better, but will require me to pipe up and over the valve cover to the intake. It also makes bracing the supercharger easier because I do not have to contend with the headers. I think this will also help reduce heat in the supercharger.
Option 1. If I mount it on the drivers side, it eliminates the possibility of using the Sniper system in a draw through setup, due to the additional charge of air in the intake possibly exploding. This forces me to use the HP system with a fuel rail.
I actually plan to run the pulley right through the powersteering pump hole. I have electric power steering installed so I don't need the pump.
Option 2. Now, if I were to mount it on the passenger side, I could mount it directly to the intake. This gets complicated due to bracing it, and it would require me to relocate the alternator to the driver side, in order to keep my belt routed correctly and have good wrap on everything. Not impossible, but additional work. This does however allow me to use the simplified sniper setup, no fuel rail, easier tuning etc.
6. Ignition (at least in my mind) now thanks to the guys on this forum has gotten simpler.
Sniper: As of now, I can use the TFI unit, Holley harness, and an Aftermarket Ign. Box to control timing. Or if I am lucky they will have the plug and play distributor out by the time I get there.
The other Sniper option is to modify all the vanes to the same width on the TFI distributor and add a crank signal. Then I think the Sniper is capable of controlling the timing without an aftermarket box. (That's what I gather from the Holley forum anyhow).
HP: I can pickup cheap used COP (Or coil near plug rather) from an LS (including plug wires). Reuse the TFI distributor, remove the vanes for my cam signal and create a cap as you guys have mentioned before. The worst part about this will be the bulky harness that comes with it. I'll have to figure out how to clean that up. Or possibly find a donor cam sync. This will require a 60-2 crank trigger.
I guess to summarize things, I'd really like to hear your input on the water/methanol, the 240 rods, head gasket, nodular crank, and which side of the motor/holley system to go with.
I am currently talking to a few different local engine builders. The one that is retired (built for the the Petty's (I think) back in the 80's and 90's), has raced 240's and 300's before, but I doubt he has any experience to help me with the fuel injection if I need it. He seemed very interested in helping build the six. The other is younger and worked for Joe Gibbs racing. Currently builds $20k plus turboed engines for mudders. I think with tuning he would be able to nail it down, but I am not so sure I can afford him, nor do I think he is that interested in my project.
As stated previously I'd ideally like 300 HP and 400 ft-lbs. But if I am sinking this kind of money into it, why stop there....so I would like the option of increasing the boost and maybe going higher. BUT IT HAS TO BE RELIABLE.
Here is what I have:
-87 4.9L
-The head completed: 2.02 Intake, 1.72 Exhaust, 1.72 Rockers, and a CNC Head Port.
-C5AE 240 no hole rods
-Custom sheet metal intake and a Clifford Intake
-Dynomax Headers
-T-5 3.35 1st, 1.93 2nd, 1.29 3rd, 1.00 4th, .68 5th
-2.78:1 Rearend
-Eaton M112 with 2.5:1 drive ratio (I can and may need to go to a larger pulley on the blower as discussed in previous threads).
Discussion/Questions:
1. I have decided 100% on a Holley EFI system (Megasquirt is ruled out). I have not decided on using the HP or Sniper unit yet. I want to discuss each option below.
2. As listed above I have already purchased remanufactured 240 rods with ARP studs, peened and polished. Will these handle the stated power, where's the cut off? or should I sell them and go for the Compstar Rods
3. I have decided to run a water/methanol injection system and for go any type of intercooler. In normal driving I wont be in the boost that much, mainly just once in awhile showing off for other car guys.
4. According to FTF in another post, the Felpro #1024 is about the best Head Gasket out there. What PSI do you think this will hold up to? OR will I need to go to copper and an O-ring (again it is a daily driver so I don't want a leaky head gasket).
5. I have a normal nodular cast crank, will it hold?
6. Which side of the motor should I mount the Supercharger on. Personally I like the drivers side. It just fits better, but will require me to pipe up and over the valve cover to the intake. It also makes bracing the supercharger easier because I do not have to contend with the headers. I think this will also help reduce heat in the supercharger.
Option 1. If I mount it on the drivers side, it eliminates the possibility of using the Sniper system in a draw through setup, due to the additional charge of air in the intake possibly exploding. This forces me to use the HP system with a fuel rail.
I actually plan to run the pulley right through the powersteering pump hole. I have electric power steering installed so I don't need the pump.
Option 2. Now, if I were to mount it on the passenger side, I could mount it directly to the intake. This gets complicated due to bracing it, and it would require me to relocate the alternator to the driver side, in order to keep my belt routed correctly and have good wrap on everything. Not impossible, but additional work. This does however allow me to use the simplified sniper setup, no fuel rail, easier tuning etc.
6. Ignition (at least in my mind) now thanks to the guys on this forum has gotten simpler.
Sniper: As of now, I can use the TFI unit, Holley harness, and an Aftermarket Ign. Box to control timing. Or if I am lucky they will have the plug and play distributor out by the time I get there.
The other Sniper option is to modify all the vanes to the same width on the TFI distributor and add a crank signal. Then I think the Sniper is capable of controlling the timing without an aftermarket box. (That's what I gather from the Holley forum anyhow).
HP: I can pickup cheap used COP (Or coil near plug rather) from an LS (including plug wires). Reuse the TFI distributor, remove the vanes for my cam signal and create a cap as you guys have mentioned before. The worst part about this will be the bulky harness that comes with it. I'll have to figure out how to clean that up. Or possibly find a donor cam sync. This will require a 60-2 crank trigger.
I guess to summarize things, I'd really like to hear your input on the water/methanol, the 240 rods, head gasket, nodular crank, and which side of the motor/holley system to go with.
I am currently talking to a few different local engine builders. The one that is retired (built for the the Petty's (I think) back in the 80's and 90's), has raced 240's and 300's before, but I doubt he has any experience to help me with the fuel injection if I need it. He seemed very interested in helping build the six. The other is younger and worked for Joe Gibbs racing. Currently builds $20k plus turboed engines for mudders. I think with tuning he would be able to nail it down, but I am not so sure I can afford him, nor do I think he is that interested in my project.
