Owner of a 152k '91 with 7psi CTSC and intercooler, AEM series 1. Car has some track history prior to 120k, when the CTSC was installed by the next owner. Seeing around 400rwhp. I don't see myself really needing more power i.e. going turbo at this point. I am not currently planning on tracking the car other than maybe the odd track day, but car is driven fairly hard on the street with frequent trips to the redline.
TB/WP/clutch were done at 120k, 9 years ago by Mark Basch along with motor mounts and a lot of other bits and pieces.
Hot oil pressure at the gauge is between 0 and 1 bar at idle and 4 bar at WOT (using a new SOS sender to repalce the factory), and using a new AEM sensor Teed off the “zero pressure” light sensor, I see ~18-22psi at hot idle and about 80psi under WOT, 60psi at 3500rpm, 75psi at 4000rpm
I had a compression test done when I bought the car a year ago:
front L-R 176-168-175
rear L-R: 172-165-150.
I just had a leak down test done in cylinder order: 3%-6%-2%-3%-1%-2%. Possibly transposed #2 and #3 though...does anyone have a diagram of which cylinders are which numbers?
So, I have a local specialist lined up to do the work and prefers engine out if possible. Cost to me is the same. He does all manner of imports, has a nitrous NSX and did his TB/WP engine out and a lot of other work including a tranny rebuild.
So, planning on the obvious minimum of:
- TB/WP
- SoS LMAs (never been done AFAIK)
- Valve adjustment
- Replace all coolant hoses
- Replace coolant and oil obviously
- Inspect clutch, replace if necessary – SOS 275? 350?
- Change Whipple oil
- Replace intercooler coolant
- Powder coat the spare set of valve covers
- replace coil pack cover seals and mounting bolts
Considering replacing/doing the following:
- Oil pump – how do my AEM sensor numbers look at the pump? Or should I do this anyway? Use the SoS new billet gears?
- Thermostat
- Motor mounts – typically necessary?
- Cam seals?
- Add an oil temp sensor?
- Inspect tranny and diff (I have a spare diff)
- Reduce exhaust noise: wrap headers and swap out cats for low mileage ones
- Sending off injectors to be cleaned/tested or upgrade to ID1000s
No need to do the following:
- clutch and brake master cylinders (done in 2013)
- replace SC belt and plugs (all done in last 4 months)
FWIW I have a spare block, crank and heads, all tested and blessed by a local well respected machine shop. Oh and a set of brand new CP pistons. Emergency backup...
I guess the real question is, given the compression test, leakdown and oil pressure, should I do a tear down and rebuild, full rebuild for power or leave as-is? I am all for saving money by combining jobs and preventive maintenance, but only if a big dollar job is really necessary.
Given engine already out of the car, what are approx $ figures for a stock motor rebuild, or a mild build with ARP, head gasket, piston upgrades plus machining? What would YOU do and why?
Thoughts on what I should also be looking at for my list, and on the (re)build question.
And if anyone has any parts I need, shoot me a PM with a price!
Thanks!
TB/WP/clutch were done at 120k, 9 years ago by Mark Basch along with motor mounts and a lot of other bits and pieces.
Hot oil pressure at the gauge is between 0 and 1 bar at idle and 4 bar at WOT (using a new SOS sender to repalce the factory), and using a new AEM sensor Teed off the “zero pressure” light sensor, I see ~18-22psi at hot idle and about 80psi under WOT, 60psi at 3500rpm, 75psi at 4000rpm
I had a compression test done when I bought the car a year ago:
front L-R 176-168-175
rear L-R: 172-165-150.
I just had a leak down test done in cylinder order: 3%-6%-2%-3%-1%-2%. Possibly transposed #2 and #3 though...does anyone have a diagram of which cylinders are which numbers?
So, I have a local specialist lined up to do the work and prefers engine out if possible. Cost to me is the same. He does all manner of imports, has a nitrous NSX and did his TB/WP engine out and a lot of other work including a tranny rebuild.
So, planning on the obvious minimum of:
- TB/WP
- SoS LMAs (never been done AFAIK)
- Valve adjustment
- Replace all coolant hoses
- Replace coolant and oil obviously
- Inspect clutch, replace if necessary – SOS 275? 350?
- Change Whipple oil
- Replace intercooler coolant
- Powder coat the spare set of valve covers
- replace coil pack cover seals and mounting bolts
Considering replacing/doing the following:
- Oil pump – how do my AEM sensor numbers look at the pump? Or should I do this anyway? Use the SoS new billet gears?
- Thermostat
- Motor mounts – typically necessary?
- Cam seals?
- Add an oil temp sensor?
- Inspect tranny and diff (I have a spare diff)
- Reduce exhaust noise: wrap headers and swap out cats for low mileage ones
- Sending off injectors to be cleaned/tested or upgrade to ID1000s
No need to do the following:
- clutch and brake master cylinders (done in 2013)
- replace SC belt and plugs (all done in last 4 months)
FWIW I have a spare block, crank and heads, all tested and blessed by a local well respected machine shop. Oh and a set of brand new CP pistons. Emergency backup...
I guess the real question is, given the compression test, leakdown and oil pressure, should I do a tear down and rebuild, full rebuild for power or leave as-is? I am all for saving money by combining jobs and preventive maintenance, but only if a big dollar job is really necessary.
Given engine already out of the car, what are approx $ figures for a stock motor rebuild, or a mild build with ARP, head gasket, piston upgrades plus machining? What would YOU do and why?
Thoughts on what I should also be looking at for my list, and on the (re)build question.
And if anyone has any parts I need, shoot me a PM with a price!
Thanks!
Last edited:
