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Hey guys, first off, this is my first post. I've been a P-car fan my entire life, spent the last 10 years squirreling away money for the "perfect" (to me) 964 C4. Mechanically inclined with all my other vehicles (BMW, Cadillac, Toyotas), and active on corresponding forums. Excited to contribute to this wonderful resource, I pulled the trigger on a 1993 964 C4 located in CA in January of this year (more on that later). The car is currently at a well known independent shop in Torrance, CA. After scouring Rennlist and other like-minded forums, my question is this: Does anyone have experience with Joe Gibbs HR1 15W-50 in the 3.6? The engine is original, unmolested to my knowledge, ~61,000 miles on it. I would also appreciate input on the COLD leak down/compression test results. COLD compression / leak down numbers came back as follows:
Cylinder: Compression: Leak Down:
1 180 10%
2 180 4%
3 181 10%
4 179 3%
5 180 10%
6 180 4%
I know pulling the leak down / compression test when cold isn't great... the car was sent to a third-party shop for a PPI (a different independent shop located in Costa Mesa), recommended by the sales broker, where the PPI with leak down / compression test was done. Assumed it would be performed hot (as it's an aircooled engine...) and got bit on that one (more on that one later). Currently, I'm just looking to drive the car regularly as I get used to the handling characteristics of the C4. Eventually DI events and autocross. Where the itch goes from there, we'll see.
I'm excited to be a part of the forum, and appreciate any input.
Last edited by MPJ964; 03-16-2018 at 02:17 AM.
Reason: Clarity
Welcome to the forum- 964 is just the ultimate air cooled narrow body IMO so you will surely love it!
I don't know why an experienced shop in Torrance (assuming callas rennsport maybe?) would do a cold compression/leakdown ..how does the car feel to you when you drive it? how is the oil pressure? how does the car pull? if all those are good then i would feel the leak down done warm & correct should show good numbers.
Thanks for the reply! Editing my post for clarity - the shop that did the original PPI is NOT the same shop that the vehicle is currently being serviced at in Torrance. Car seemed to pull well for being 25 years old; but I can't recall the oil pressure.
Last edited by MPJ964; 03-16-2018 at 02:23 AM.
Reason: Rude
I have a 90 C2 with a partial top end and reseal done two years ago and I just started using Joe Gibbs as of January this year. Thus far the car runs quieter and smoother than before, even on cold startup. I haven’t observed or smelled any oil leaks either and oil pressure is spot on. I’ve driven it maybe 800 miles since and haven’t noticed any smoke at startup, no smell or measurable oil usage.
Last edited by Marine Blue; 03-16-2018 at 10:17 AM.
I know pulling the leak down / compression test when cold isn't great... the car was sent to a third-party shop for a PPI (a different independent shop located in Costa Mesa), recommended by the sales broker, where the PPI with leak down / compression test was done.
Congrats on the purchase and you are right about the numbers, not very meaningful if done cold. What is done is done, but NEVER have the selling party chose the place for your PPI. You may want to post the shops where the PPI was done and where the car is at currently, there is enough knowledge on this board to give you further information to make sure your are in good hands. As for the Joe Gibbs oil, the short answer is that there should be no issue as long as it has the proper levels of ZDDP.
Currently, I'm just looking to drive the car regularly as I get used to the handling characteristics of the C4. Eventually DI events and autocross. Where the itch goes from there, we'll see.
First, thanks for the replies. You folks are awesome. I bought a liter of Joe Gibbs HR1 and sent a sample out to Blackstone Laboratories. VOA results coming soon.
Work has been insane, so I haven't had time to reply as of late. My apologies.
Speaking of late, better late than never:
Being loaded for transport to indy shop.
Currently, the vehicle is "finished" (for now).... 60K service done, a couple parts replaced, ride height, alignment corner balance completed, some electrical work done... Wallet got quite a bit lighter. Hoping to have the dash gauge face recovered, but waiting on a upholstery shop to get a quote... also possible minor paintwork.
Any idea what it would cost to replace the lower dash panel and recover the gauge cluster face? Photos below (don't mind the body plugs).
A new use for body plugs
That looks expensive.
Previous owner had a radar detector installed in the 90's... I had it removed and the wiring harness repaired... Which happened to sort the radio out as well. Bonus!
Update on leak down/ compression numbers - I had the shop perform the tests again:
Shop that had done 60K service under previous owner had over-tightened some of the valves, so I'm glad I had the work re-done out of caution. This car has been a learning experience so far.
Wow! Car looks real nice. It looks like your wheels are a mismatch front to rear. The fronts are Cup II (993 style) and the rears are Cup I (964 style).
Wow! Car looks real nice. It looks like your wheels are a mismatch front to rear. The fronts are Cup II (993 style) and the rears are Cup I (964 style).
Thanks for the replies guys. These photos are prior to it getting any work done. Since then, it's had some paint-less dent removal work, as well as the front bumper repaired and resprayed. And yes, the wheels are mismatched - the vehicle had been in an accident, unbeknownst to the previous owner. I am owner #3. There are 3 OEM Cup I wheels and one OEM Cup II wheel with Michelin AS3's mounted (205/50/17 front & 255/40/17 rear). All wheels chromed. Going to pull them off shortly and replace with a set of 17" Sport Classic I's with Michelin PS2's (225/45/17 front & 255/40/17 rear). At some point, I'll have the Cup wheels checked out. If they pass, I'll look to have them de-chromed and cleaned up, and find an OEM replacement Cup I wheel to complete the set. Those will be my winter wheels.
03-16-2018, 01:14 AM
First Post: Joe Gibbs HR1 - 1993 964 C4
It looks like your wheels are a mismatch front to rear. The fronts are Cup II (993 style) and the rears are Cup I (964 style).
