Fuel Pump and Headgastket Question
01-29-17, 05:08 PM
#1
Fuel Pump and Headgastket Question
I have a 92 SC3 that has not run in at least 4 years, with that being said I am finally getting a chance to get her back on her feet and will be pulling the motor out for a fresh rebuild here in the next couple weeks. My plan at this time is to stay NA, just get it back running so I can enjoy a reliable car, and maybe in a couple years go turbo (undecided at this time). I have two questions
1. Since I am replacing the HG, would there be any loss in power or any Cons in putting a TT head gasket on now and staying NA, so that I wouldn't have to do so latter if I would decide to go turbo?
2. I will be replacing my fuel pump and strainer and was originally planning on going with an OEM spec one, but should I go ahead and upgrade to at least a TT pump and strainer now or wait til later? If or when I would boost my horsepower goal would probably be in the 500-550 range, if that helps at all
Thank You in advance
-Scott
1. Since I am replacing the HG, would there be any loss in power or any Cons in putting a TT head gasket on now and staying NA, so that I wouldn't have to do so latter if I would decide to go turbo?
2. I will be replacing my fuel pump and strainer and was originally planning on going with an OEM spec one, but should I go ahead and upgrade to at least a TT pump and strainer now or wait til later? If or when I would boost my horsepower goal would probably be in the 500-550 range, if that helps at all
Thank You in advance
-Scott
01-30-17, 12:13 AM
#3
Moved to Performance and Maintenance section and removed your duplicate thread, OP.
I agree with Stretch21. If you are not in a strict emissions area just go with an OEM TT head gasket, ARP studs (but OEM Toyota stud washers) and you will be better prepared for boost down the road. Power will be down due to lower compression however since you will be going from a super thin GE gasket to a 1.3mm TT gasket. I am not sure by how much. The ECU will compensate if you are staying NA but the response won't be quite a snappy as 10.0:1 while you are naturally aspirated.
Are you considering different pistons and an overbore as well or are you going to re-ring your OEM 10.0:1 pistons? FYI, Toyota does not sell overbore GE 10.0:1 or GTE 8.5:1 pistons, just the factory 86mm bore size. It is aftermarket only if you want an 86.5mm pistons and rings (and most availability is in 2618 forged alloy but I think a couple of reputable piston manufacturers may still sell 4032 forged for the JZ).
If you are removing the engine I would also recommend removing the oil pan, cleaning it and tapping out the un-machined turbo oil drain port and adding a -10AN turbo drain fitting with a cap for now. It is best for you to take care of that modification with the oil pan removed rather than attached. You don't want to get any shavings into your your rotating assembly.
For bearings you can order new OEM close sizings from Toyota or any place that will sell you the specific part numbers based on your block, crank and rods numbers or you can go with a set of Clevites or ACLs.
I did this recently with my GTE block build. Same procedure for GE/GTE. In post #306 the oil pan turbo drain tap is documented first. Then the OEM Toyota bearing sizing process. Aftermarket bearings in "standard" sizing don't require the procedure outlined to get the right fit. It's up to you which route you want to go when doing your rebuild:
https://www.clublexus.com/forums/bui...ml#post9726193
I also agree with Stretch21 about the fuel pump. Get the Denso OE replacement (you can get it from Toyota or from an auto parts store that sells the same thing. You want Denso #950-0109 which has the strainer. I did this recently too and it is not difficult. Though I do recommend using a thick rag to block the open gas tank fumes and a mask (or a ventilated mask if you prefer).
You could install an OEM Denso Supra TT fuel pump or an aftermarket pump but you would need to perform the +12V Mod with a relay to give the pump the needed constant +12V with the safety shut off feature. You will need to do that later anyway but if you are not going to boost yet it is easier to just replace the inexpensive NA fuel pump for now and have less to change. Stretch is right. It is not a difficult job.
I have a Denso TT fuel pump waiting to be installed into my car but for the same reason I recently just installed a new Denso NA pump to keep things simpler while I still have a stock non-boosted engine.
Good luck!
I agree with Stretch21. If you are not in a strict emissions area just go with an OEM TT head gasket, ARP studs (but OEM Toyota stud washers) and you will be better prepared for boost down the road. Power will be down due to lower compression however since you will be going from a super thin GE gasket to a 1.3mm TT gasket. I am not sure by how much. The ECU will compensate if you are staying NA but the response won't be quite a snappy as 10.0:1 while you are naturally aspirated.
Are you considering different pistons and an overbore as well or are you going to re-ring your OEM 10.0:1 pistons? FYI, Toyota does not sell overbore GE 10.0:1 or GTE 8.5:1 pistons, just the factory 86mm bore size. It is aftermarket only if you want an 86.5mm pistons and rings (and most availability is in 2618 forged alloy but I think a couple of reputable piston manufacturers may still sell 4032 forged for the JZ).
If you are removing the engine I would also recommend removing the oil pan, cleaning it and tapping out the un-machined turbo oil drain port and adding a -10AN turbo drain fitting with a cap for now. It is best for you to take care of that modification with the oil pan removed rather than attached. You don't want to get any shavings into your your rotating assembly.
For bearings you can order new OEM close sizings from Toyota or any place that will sell you the specific part numbers based on your block, crank and rods numbers or you can go with a set of Clevites or ACLs.
I did this recently with my GTE block build. Same procedure for GE/GTE. In post #306 the oil pan turbo drain tap is documented first. Then the OEM Toyota bearing sizing process. Aftermarket bearings in "standard" sizing don't require the procedure outlined to get the right fit. It's up to you which route you want to go when doing your rebuild:
https://www.clublexus.com/forums/bui...ml#post9726193
I also agree with Stretch21 about the fuel pump. Get the Denso OE replacement (you can get it from Toyota or from an auto parts store that sells the same thing. You want Denso #950-0109 which has the strainer. I did this recently too and it is not difficult. Though I do recommend using a thick rag to block the open gas tank fumes and a mask (or a ventilated mask if you prefer).
You could install an OEM Denso Supra TT fuel pump or an aftermarket pump but you would need to perform the +12V Mod with a relay to give the pump the needed constant +12V with the safety shut off feature. You will need to do that later anyway but if you are not going to boost yet it is easier to just replace the inexpensive NA fuel pump for now and have less to change. Stretch is right. It is not a difficult job.
I have a Denso TT fuel pump waiting to be installed into my car but for the same reason I recently just installed a new Denso NA pump to keep things simpler while I still have a stock non-boosted engine.
Good luck!
Last edited by KahnBB6; 01-30-17 at 12:20 AM.
01-30-17, 12:14 PM
#4
Thank you guys for your feedback/help.
The reason I was considering the TT fuel pump instead of doing a stock oem replacement on my SC is because the Denso TT pump is only $40 more. I figured if the TT pump on a stock GE motor wouldn't cause the car to run funky, I should just spend the extra $40 now instead of having to purchase another pump down the road. Thoughts? I will also look into what is all required for the 12V mod and take that into consideration.
Kahn- I am planning on a re-ring on the factory pistons unless I find damage when I pull the head. Also, I am planning on dropping the pan, but didn't even think of tapping it for a turbo line while it was apart, so thank you very much for that Idea, makes a lot of sense! I will have to drain the fuel that is currently in the tank since it is junk at this point from sitting so long, so I am just going to have to deal with the fumes.
Thank you guys again, I am really looking forward to get my car running again. I sold it back in 2007 due to hard times and then was able to buy it back from the kid who bought it from me in 2013 when he jacked it up, so it has been sitting since. All I know is that he over torqued the cam gear bolt into the cam which caused the cam to break from there I am unsure of any other damage etc to the engine/drivetrain.
The reason I was considering the TT fuel pump instead of doing a stock oem replacement on my SC is because the Denso TT pump is only $40 more. I figured if the TT pump on a stock GE motor wouldn't cause the car to run funky, I should just spend the extra $40 now instead of having to purchase another pump down the road. Thoughts? I will also look into what is all required for the 12V mod and take that into consideration.
Kahn- I am planning on a re-ring on the factory pistons unless I find damage when I pull the head. Also, I am planning on dropping the pan, but didn't even think of tapping it for a turbo line while it was apart, so thank you very much for that Idea, makes a lot of sense! I will have to drain the fuel that is currently in the tank since it is junk at this point from sitting so long, so I am just going to have to deal with the fumes.
Thank you guys again, I am really looking forward to get my car running again. I sold it back in 2007 due to hard times and then was able to buy it back from the kid who bought it from me in 2013 when he jacked it up, so it has been sitting since. All I know is that he over torqued the cam gear bolt into the cam which caused the cam to break from there I am unsure of any other damage etc to the engine/drivetrain.
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