This 1985 IROC-Z has the original 305 V-8 engine with Tune Port Fuel Injection. The car runs and drives pretty good and even has some pep to it. It chirps 2nd gear so i’m assuming someone rebuilt the transmission at some point and maybe put a shift kit in it. I believe it’s a 700R4. Good transmission but it too will receive an upgrade. The engine has 97k miles on it but you wouldn’t think that based on the condition of the car. It was well kept and maintained most of it’s life. I’m pretty sure it has been kept indoors since day one. There is zero rust on the whole car and a quick pressure washing revealed much of the original blue overspray paint on the undercarriage. Also while on the lift I found out these cars are kind of difficult to put on a two post lift. They are low and there are not many options for lift points without damaging things. In this case, both front fenders bolt to the pinch weld (which is normally a good spot to lift a car), but in this case it cannot support the weight of the car and instead ends up smashing the fender flange, causing bad fender to door to hood panel fitment and bad gaps. I straightened out those flanges and the panels instantly fit much better. I may end up doing something different that will make putting this car on the lift much easier.
The TPI old school V8 is going bye bye but I may keep it around as sort of a museum piece. Since it is an IROC engine it may be something people are searching for in the future, or not. This week we will begin our video content on the 2016 LT4 that came out of a Z06 Corvette. I wanted to get an LT4 out of a ZL1 Camaro just to keep it all in the family but I ended up getting a great deal on the corvette one and I’m finding it has some benefits, I think. There are basically two versions of the LT4 Gen V engines (though there are minute differences from year to year such as the supercharger hats and supercharger internals), for the most part they are all the same engines. The main differences to look out for when purchasing a used or new one is wet sump vs. dry sump. Now, I don’t have a ton of experience dealing with dry sump engines (though i’ve been involved with some of this on high horsepower cars at Rad Rides such as the Blowfish Bonneville land speed car, and some other twin turbo cars that came out of that shop. Because the availability of these engines is somewhat low, especially low mileage ones that are in good condition, I had to take what I could get when it came to oil management. The engine I got is a dry sump engine (which i’m assuming all Z06’s were dry sump due to packaging constraints). The corvette is a lower, thinner car so cramming a large engine into them is sort of an engineering feat in itself. But what this means is GM has already figured out how to make this large package as sleek and slim as possible. The dry sump oil pan is much more conducive to clearing the F-Body crossmember. We will have to figure out how and where to put a remote oil tank and route a couple of large -12 oil lines but that has already been done and shouldn’t be a problem. We may need to ditch the factory washer fluid reservoir but that’s what they make Rain-X for. Also this week we will film the process of removing the old serpentine front runner along with the accessories so we can install the new Holley mid mount system which comes with more desire-able components which lend themselves better to a custom, hot rod type application. I do not know for sure if the Holley mid mount set up is the perfect solution for and LT4 in a third gen but i’m about to find out and so are you! What I do know is that the stock corvette setup is not going to work as the components such as the air compressor are too low on the block and will be in the way. The other major issue with the stock setup is the lack of a hydraulic power steering pump. The corvettes (and I think the ZL1’s and CTS-V’s) all have electric power steering racks which we will not be hassling with. We plan on using the upgraded quick ratio gear box from Detroit Speed on this build along with their bold on front suspension and struts. There are several things I plan on modifying on this car but I don’t need to re-engineer what other great companies have already developed. I’m not interested in cut-throat product competition, though I am interested in developing some parts where there is a gap in the industry.
The first thing we need to do this engine swap is some proper engine mounts. There are a few options available out there for doing this swap but I felt like Hawks Motorsports had the best solution for my situation. I even called them to talk with their tech department to make sure this was a direct fit and the confirmed it is. The only thing (according to Hawks) that needs to be modified is the factory third gen heater box needs a notch cut in it to clear the engine. I’m ok with that. We will make a plastic patch and bond it in place to fill the hole and be done with it. The Z06 engine mounts are huge and bulky. I’m sure they work great for vibration dampening but they’ve got to go! Another thing we need to figure out is the headers. There are a couple of options for this swap available but honestly i’m not in love with either one of them. We have already been in contact with a header manufacturer about developing a CNC bent stainless header for this exact swap application. Stay tuned for that! The Hawks engine mount kit also has the option for selecting what transmission you want to run. So in this case I got the TR6060 trans mount kit. One thing I don’t care for on the Hawks kit is the red urethane bushings. Why does everyone make red bushings?! Just make them black and call it a day. The red is soooo gawdy! We may just use them for mock up and find some black ones because it bugs me that much.
Also for this engine swap we will need a few other smaller (not cheaper) items such as a dry sump A/N line adapter that will replace the factory aluminum pre-bent lines coming out of the oil pan. This we ended up getting from Hawks also. Then we had to get an oil cooler relocation adapter that eliminates the HUGE OEM one that is right in the way of the headers. Improved Racing makes some nice solutions for this but they aren’t cheap. We opted for the one with the internal thermostat which is supposed to improve engine wear on daily driven vehicles by not overcooling or over heating the engine oil. This also comes with A/N fittings that will get plumbed to an external cooler, most likely up by the radiator or maybe we do some custom air inlet ducts in the plastic facia!!
Ok, so we are doing the TR6060 six speed that came out of a 2019 ZL1 Camaro. Different car than the engine, but similar family of parts which makes it much easier to do a swap like this. The Corvette LT4 didn’t come with the clutch, flywheel, or pressure plate or hardware so I had to search for some parts. I did end up getting the exact clutch that came out of this low mileage transmission but no flex plate or pressure plate. I found those on ebay which also came from a low mileage car. I was looking into new beefier clutch options but decided I didn’t want to spent $2500 on a dual clutch at this time. If the OEM one was good enough for GM to put in these cars it will be good enough for the time being. We may upgrade to a better clutch later after we pound on it a bit. I also had to hunt down new metric bell housing bolts, flywheel bolts, and clutch mounting bolts. I’ve heard you might as well replace the pilot bearing while it’s all apart so I got one of those from Amazon along with a bearing installation tool from ICT billet (also Amazon). All this being said, we should be good to mate the engine, clutch, transmission together in an upcoming video.
Since we are using a 6 speed out of a ZL1 Camaro and since I don’t really care for the original boxy center console (with no cup holders), I decided to see if we can make a console from a 2010 Camaro fit this car. It already fits the shifter, shifter booth, has the H-pattern on the plastic part, has some cool options for center console gauges (including a boost gauge) and most importantly it comes with not one, but two cup holders, an arm rest compartment with USB charge port and cigarette adapter inside it. It also has the OEM provision for a better looking parking brake handle which I do plan on getting and retro fitting to this car since I have the ZL1 brembos with the internal parking brake.
Levi
1985 IROC TPI 305 V8
LT4 out of a 2016 Z06 Corvette
TR6060 six speed manual transmission out of a 2019 ZL1 Camaro
Holley Mid mount serpentine kit
Holley Mid mount serpentine kit (exploded view)
Diagram of Holley Mid Mount pulley system