LS1 V8 fd conversion progress thread

[Spartacus]

A quick update on progress today. As I have said before this is turning more into a major overhaul project rather than a simple engine conversion, mainly as it\'s just too good an opportunity to miss when parts of the car are so much more accessible at the moment. I’ll include all I’m doing although a lot of it isn’t necessary for the V8 conversion. Today was spent undersealing the back of the car while the rear subframe is off. Little tip to anyone else doing this, start from the middle of the car and work out. Then you might just end up with more underseal on the car than on your head, trust me I know!
The good news is that I received a package from the US which has a few bits I\'ve been waiting for which includes a Corvette fuel filter/fuel pressure regulator which also includes a return line output to the tank. It will go in the same place as the Mazda filter and it\'s even the same size so you can use the same mounting bracket, easy eh. I also received and changed the fuel pump for a Supra TT pump which should take care of all the fuel needs of the LS1.
Unfortunately my local motor factors only had 4 fuel hose clamps so I couldn’t finish the filter/fpr install but all the lines are made and ready to fit.

[M@r]{]

This thread has made an interesting read - look forward to see (and hear!!) this baby!   I remember a while ago some guy posting up a vid of a V8 RX, it sound sublime!

[Spartacus]

The quick update for today is a bit more relevant to the actual V8 conversion:cheers . The ls1 has a water temp sender on the left hand cylinder head but that is for the ecu rather than for the gauge, but as luck would have it there is another point on the right hand head that can be used for a second sender. Basically you have 2 options, the first is to install (via an adapter) the Mazda temp sender and use your existing gauge or the second option is to install an aftermarket sender and change the gauge. As the 2nd option gets rid of the non linier Mazda gauge and sounds so much more fun (not) that’s the way I have gone. The sender and adapter was easy enough to fit but I\'ll leave the gauge install for a latter instalment (got out of that one eh?:Giggle )

I also changed the thermostat from the factory 195 deg (I think) one which is very easy to do as it doesn’t even have a gasket, just a nice rubber O ring on the new thermostat. There is a lot of conjecture over what thermostat is best for the ls1 in the US. Some say that the engine was designed to run hot and others say that the reason that it runs hot is just for emissions reasons, and that more power is available if it runs a bit cooler. Until recently 160deg was the preferred option but there is now a 180 deg option which is what I have gone for (sitting on the fence here;) ). More to come soon.:wave

[shaunwil]

I\'ve seen people install the defi gauges in the stock cluster. Either a howto on here or on rx7club. The non-linear one is naff !

Shaun

[Spartacus]

I\'ve seen people install the defi gauges in the stock cluster. Either a howto on here or on rx7club. The non-linear one is naff !

Shaun

I will be doing something very similar, I\'ll put an after market water temp gauge and oil pressure gauge in the stock positions in the cluster and use the stock fronts and needles so no one will ever know, na ha ha :evillaugh (then pray it works) When I get a chance to finish it I\'ll add it to this thread.

[Spartacus]

Here\'s a quick taster

[Spartacus]

Today’s (ok an hour or two) progress was to take off the original GTO type engine mounts which can be seen in the 1st pic and swap them with F body types which are required when you use the Hinson Subframe. As well as changing to the F body type I took the opportunity to change to a polyurethane mount rather than the standard rubber to limit engine movement. To do this you need to drill out the rivets that hold the 2 halves of the mount together, split the mount, remove the bonded in rubber portion and replace them with the poly ones. Then just bolt the 2 halves back together and bolt to the block.

[Carl]

If you mean here, I have no idea but I have just loosely assembled the Y pipe the way it looked liked it wanted to be put together just for the picture. It may be completely different when I come to put it on the car.

The header must be bent for a left hand drive car\'s steering,you might need to swap some bits about and cut and shut the exhaust for right hand drive.
Keep up the good work.
Regards
Carl

[Spartacus]

The header must be bent for a left hand drive car\'s steering,you might need to swap some bits about and cut and shut the exhaust for right hand drive.
Keep up the good work.
Regards
Carl

From what I\'ve been told by Brian (Mr Hinson) they have made a custom right hand exhaust manifold to fit on a rhd installation. I would think that I have their standard left hand manifold designed as you say to fit around the left hand drives steering column. Time will tell as to how good the fit is :2Rolleyes

[Spartacus]

Today’s task was to change over a hydraulic fitting on the clutch slave cylinder, as the clutch line sent by Hinson’s had a quick connect fitting that you would find on a F body type slave and I have a GTO type. My GTO type slave is exactly the same apart from it has a short length of hard line coming out of the bell housing and terminating on a much smaller quick connect fitting.

A hero in the US:god  who has been collecting and sending over all those hard to get fuel line fittings etc on my behalf luckily had an old F body slave cylinder laying around so he sent that over so I could cannibalise it and use the fitting from it.
The first pic shows a GTO type fitting with the hard line and in case you’re wondering the fitting above it is the bleed. The second pic is the clutch line I need to attach to the slave, the third is of my slave and the f body one so you can see the difference and the forth is the fitting swapped onto my slave cylinder. As with most things so far it was very easy to do, just needing the small retaining pin punched out, carefully removing the fitting to make sure it comes out with the rubber O ring intact and just replace with the other fitting and tapping back in the pin. I must say everything so far has been really simple (it must be if I can do it:Thumbsup! ). Saying that, I will be connecting up the master cylinder and checking it all works before the gearbox goes back onto the engine just in case

[Spartacus]

As promised a post on how to modify the stock cluster to use aftermarket oil pressure and water temperature gauges.
I can’t take the credit for coming up with the mod as I came across it on another site, but it may be useful to those either doing this conversion or anyone just wanting more effective oil and water gauges.
The gauges I used for the swap are from the US but I’ve been assured that most 52mm gauges with the same sweep as the Mazda ones would work just as well.

First off, take the factory gauge cluster apart so you can get to the individual gauges. Take out the factory temp and oil gauge by first carefully (as you will reuse these) pulling off the needles then the gauge faces. Behind the cluster you will see 3 small screws behind the gauges that hold the gauge body to the cluster. Undo these and the gauge will come away.
Next take apart your new gauges, both gauges once taken apart look IDENTICAL, so make sure and label (or remember) which is which. Below is the oil gauge disassembled:

Now here’s the interesting bit, your newly stripped gauge has more than likely got the exact 3 bolt pattern as your old Mazda units the only difference being that the electrical connections will be different. So you just place them into the cluster (in the right positions)
Here is the water temp gauge installed.

And here with the new oil pressure gauge in its factory location, again using the stock 3 holes,

And lastly a closer look with both new gauges installed.

Next, put the factory water/oil faces over the new gauges, and put the factory gauge needles on your new gauges to line up where they originally were. You will notice that there is no way of mounting the stock faces down since the holes on the gauge don\'t align with the stock face plate, don\'t worry. You won\'t need to secure it because when you re-assemble your cluster, the black face plate (that surrounds the cluster) has dowels that will hold it in place, it’s hard to explain, but it works out great.


Now you can reassemble the front of your cluster and with any luck it will look something like this.
Now for wiring.
Firstly you need to carefully lift the green flexible circuit board away front the back of your new gauges and insulate with a few layers of tape where the bolts would go through and would touch. I also used some masking tape just to hold the circuit board away whilst I did the wiring. I decided to use the pos/neg slots that the fuel gauge uses, reason being, it was close by.

You need to take note of what pegs on the new gauges are POS, NEG, and for the SENDER. If you look at the pictures below I ran the POSITIVE (red) wire from the new gauges, to a spot on the fuel gauge. I did the same thing for the NEGATIVE (black).

Here you can see the back of my cluster ready to go back in. I’ve probably used a far heavier gauge wire than necessary but it was close to hand.
With the sender wires you have the option of tracing out where the original goes on the cluster connector and splicing it to it or running it directly to the gauge sender, which is what I am going to do.

I hope this helps for those who want a stock look, yet accurate linier gauges.

[RobbieRX-7]

That\'s a really really cool mod, but how did you make sure the needles went on properley? Like you dont want the reading to be off.

[Bulla]

Great thread keep up the good work. :Thumbsup!

[Spartacus]

That\'s a really really cool mod, but how did you make sure the needles went on properley? Like you dont want the reading to be off.

If you think about it the needle doesn’t need to go on the same position on the gauge spindle where the other one came off. The spindle doesn’t know where the needle is it will just move through its arc in correspondence to the resistance of the sender. So long as you put the needle back on at the beginning of its sweep on the gauge face it should all be ok. The only thing you need to make sure of is that the new gauges have the same arc of movement as the old Mazda ones. Haven’t put all that very well but hopefully it makes sense.

Mr B thanks for the encouragement. :cheers

[Spartacus]

Little bit done today in between showers. I finished off the fitting of the new Corvette fuel filter/pressure regulator, all in one and gives the LS1 the required 58psi nice eh? Also it’s very nearly the same size as the Mazda filter, and even fits in the Mazda bracket in the original position.:Party


I used a mix of some new high pressure fuel hose and a part of the original hoses (to get a nice bend) along with double hose clamps (just to be on the safe side:yes ) onto the Mazda hardline into the engine bay. The return line is no longer needed as the Vette filter/fpr has a return outlet as part of the unit so that goes straight back into the tank.
I decided not to try and get the evap line working for a couple of reasons, the main one being that the charcoal canister needed to come out as it wouldn’t fit with the new bracing on the subframe. Secondly, I would have needed to fit a pressure sensor in the fuel tank and connect it up to the new ecu for it all to work anyhow. In the end I took off the hose from the hard line and ran it up near the fuel tank vent pipe.

Now this was done I could fit the modded subframe with the diff already mounted (much easier way of doing it) onto the car making sure the handbrake and abs cables didn’t get caught (eventually:rolleyes: )


Once everything was bolted up I could then start to fit the suspension arms back on. But then the rain got the better of me so back it went into the garage to wait for another day:Snoring .