Time to pick brains for spare parts suggestions.

[jstricker]

This will be our first Lemons car that's been turbo'd. The other two we've run have both been N/A and we've had good luck with those motors for the most part. I'm looking for suggestions in two areas.

First, the engine will be basically stock as far as power adders. Stock IC, stock turbo (mostly), the goal is to make it appear to be stock looking from the outside. It also can't be TOO fast because that sets off all kinds of red flags and could result in the car getting crushed. Now keeping that in mind here are the plans for the motor:

Stock re-build of the top and bottom end. I have a set of new valves that I bought with other parts. The crank is good. Add ARP rod bolts for sure as well as ARP head studs. Surface the head and block. I'm planning now on going with a Cometic head gasket as opposed to a MHG. Stock pistons if possible. New bearings.

I'd like suggestions on the oil pump. Is stock good enough? I see there are options out there. I'm going to have to stick with the stock oil cooler/filter setup for appearance (it can NOT look too built). I was planning on using a set of N/A cams in the engine (I have several sets) but from what I read the power addition is little to none over the turbo cams, correct?

Of course, any other suggestiions are appreciated as well as long as you keep the Lemons ground rules in mind, that is CHEAP and has to LOOK STOCK.

Second, we really didn't have many spares for the engines at the track with the N/A motors. We took an extra timing belt an tensioner but never needed them. Fuel filter (did need it once) and an extra fuel pump. Coil and distributor.

For the Turbo, what would you turbo gurus suggest? Extra CPS? Are they a weak spot? Igniter? Coil Pack? These are the kinds of things that can be picked up reasonably here on the forum but I don't want to buy them if I don't need them, of course. You can also include other parts of the car as well, but mostly I'm unfamiliar with the common weak points of the turbo motor as opposed to the rest of the car.

In short, if you were building run to race for 24 hours straight, what spares would you turbo gurus take with you "just in case"???

John Stricker
Russell, KS
DOGMA Racing

 

[SideWinderGX]

Depends what you've done to it.

I'd replace all the coolant hoses (ALL). Fix the CPS wiring and make sure it isn't brittle. Look around and check the wiring for the coil packs and the igniter. Speaking of that, go search for jetjocks igniter mod, that's a little something you can do.

If everything there is done bring little electrical odds and ends like the coil packs, igniter and CPS...but I doubt they'll die on the track. Assuming you do a good job with the headgasket and cooling isn't a problem (radiator/fan in good shape, or aftermarket even) nothing should surprise you.

Oh, oil. Bring some extra oil.

 

[GrimJack]

^^^ What he said... and:

Stock oil pumps are fine. I'm not sure what the G-forces during the turns are like for Lemons, but you might want to work on baffling the pan a bit better, there's folks who have starved the oil pickup in high G corners. Or mess with the oil pickup. Or run an extra liter of oil. Personally, I run an extra liter of oil.

Replace all the damn vacuum lines, too. They are super cheap, and there are several that will play havoc with the system if they pop. And if you're running an early model GTE, replace that damn rubber plug on the coolant hardline on the firewall, near the back of the exhaust manifold.

The area I'd spend most of my effort would be the cooling system. Make sure it has a fan shroud. Buy a new fan, fan clutch, and water pump. Get them dirty after installation if you want them to look cheap. New radiator cap. New water pump belt. New overflow hose, including the 4" pickup line in the overflow bottle. Make absolutely certain you've eliminated any coolant leaks. The fastest way to test this is to add some water wetter to the coolant and take it for a run, then check for leaks. Water wetter changes the surface tension in water to a much smaller value, allowing it to leak through significantly smaller areas. I wouldn't run it during the race, but there's no better way to find and eliminate leaks in advance.

If you're going to crack open the engine, it's worthwhile to add new bearings, get the crank opened and cleaned out, and to be honest I'd install a set of JE pistons. The stock ones give you ZERO margin for error when it comes to detonation, and I don't think the inspectors will be able to tell what kind of pistons are in there! It's not a power adder, just extra insurance.

I'm not fond of the cometic gaskets - I've popped one, whereas the HKS I used has survived everything I've thrown it's way. They are both MHGs, by the way. You can even use a used one, just strip the viton coating and use copper spray instead. You'll have to strip the viton on every layer, mind you. I also pull the rivets and just use the block pins to line up the pieces, there's been too many issues with rivets between the sealing surfaces preventing a good seal. On that note, remember to machine the timing cover on the front with the block, they both need to be the same height for the gasket to seal.

Add in a $20 manual boost controller and you should be pretty damn quick for pretty damn cheap. Oh... and exhaust. You're going to need a 3" exhaust, preferably from the turbo back. That cast iron elbow, downpipe, catalytic converter, and exhaust are hugely restrictive. Fab up something cheap that looks like crap, and it'll probably be the most expensive part of the car that the judges can find.

Lastly, you can drill out the plug on the AFM and mess with the adjusting screw to give you a little more boost before fuel cut kicks in. Might make all the difference!

 

[jstricker]

Excellent, that's just what I'm looking for. All of the hoses will be new, certainly. The block and head will be surfaced with a new head gasket and ARP Studs. I'll do the search for the igniter mod you suggested, I'm completely unfamiliar with the Turbo's ignition having been dealing only with the N/A distributor/coil in the past. If I understand you correctly, it WOULD be a good idea to bring another coil pack, igniter, and CPS (even though unlikely to fail during the race......)? That can be done. Spare parts don't count towards the budget, only the parts that are physically on the car.

The radiator is going to have to be new, but it's also going to have to be reasonably priced. I see HPF has a Megan radiator for under $200 + shipping. Right now it has a twin electric (NOT the a/c fans) and a shroud. I'd personally prefer a good stock mechanical belt driven one to reduce the electrical load (remember, this will have about 12 hours of night racing with lights, fuel pump, etc. drawing on the alternator) but we'll see what happens there.

Thanks for the suggestions, keep them coming.

John Stricker
Russell, KS
DOGMA Racing

 

[jstricker]

^^^ What he said... and:

Stock oil pumps are fine. I'm not sure what the G-forces during the turns are like for Lemons, but you might want to work on baffling the pan a bit better, there's folks who have starved the oil pickup in high G corners. Or mess with the oil pickup. Or run an extra liter of oil. Personally, I run an extra liter of oil.

Believe me, I'm taking all of this to heart, you guys have the turbo experience, I don't! (well, unless you count diesel blowers and turbos where I think I might have most people here beat, but that's an animal with different stripes.) I'm pretty much planning on replacing the oil pump with a new one, glad to know a stock one is sufficient. If we run a quart overfull, is a crank scraper necessary/beneficial? They're not that expensive and seems like it might add a bit of insurance helping to keep the oil in the bottom.

Replace all the damn vacuum lines, too. They are super cheap, and there are several that will play havoc with the system if they pop. And if you're running an early model GTE, replace that damn rubber plug on the coolant hardline on the firewall, near the back of the exhaust manifold.

Good suggestion on the vacuum lines. There won't be as many as a street car but there are still plenty of them. The car is an '88 for what that's worth.

The area I'd spend most of my effort would be the cooling system. Make sure it has a fan shroud. Buy a new fan, fan clutch, and water pump. Get them dirty after installation if you want them to look cheap. New radiator cap. New water pump belt. New overflow hose, including the 4" pickup line in the overflow bottle. Make absolutely certain you've eliminated any coolant leaks. The fastest way to test this is to add some water wetter to the coolant and take it for a run, then check for leaks. Water wetter changes the surface tension in water to a much smaller value, allowing it to leak through significantly smaller areas. I wouldn't run it during the race, but there's no better way to find and eliminate leaks in advance.

I always used a couple of teaspons of dish soap but water wetter won't make any foam. I'm going to have to look and see what spares in the mechanical fan area I have. I know I do NOT have a spare factory shroud (I wish I did) but I think i have an extra fan and clutch assemble although it's off an N/A engine, I believe they're the same, correct me if I'm wrong.

If you're going to crack open the engine, it's worthwhile to add new bearings, get the crank opened and cleaned out, and to be honest I'd install a set of JE pistons. The stock ones give you ZERO margin for error when it comes to detonation, and I don't think the inspectors will be able to tell what kind of pistons are in there! It's not a power adder, just extra insurance.

I'm not fond of the cometic gaskets - I've popped one, whereas the HKS I used has survived everything I've thrown it's way. They are both MHGs, by the way. You can even use a used one, just strip the viton coating and use copper spray instead. You'll have to strip the viton on every layer, mind you. I also pull the rivets and just use the block pins to line up the pieces, there's been too many issues with rivets between the sealing surfaces preventing a good seal. On that note, remember to machine the timing cover on the front with the block, they both need to be the same height for the gasket to seal.

Thanks for the tip on Cometic gaskets. I haven't heard this before but I admit I'm still researching this stuff and there are only so many hours in the day. The engine is already open, I bought the car with a blown head gasket the PO had already pulled the head on to replace. SUPPOSEDLY before the head gasket blew the bottom end had just been gone through but it's all getting pulled apart regardless for inspection and new bearings.

Add in a $20 manual boost controller and you should be pretty damn quick for pretty damn cheap. Oh... and exhaust. You're going to need a 3" exhaust, preferably from the turbo back. That cast iron elbow, downpipe, catalytic converter, and exhaust are hugely restrictive. Fab up something cheap that looks like crap, and it'll probably be the most expensive part of the car that the judges can find.

Lastly, you can drill out the plug on the AFM and mess with the adjusting screw to give you a little more boost before fuel cut kicks in. Might make all the difference!

We're on the same page with the manual boost controller. I'm also adding a decent boost gauge since gauges don't count to the limit (I believe). My plan was to take the controller out for tech inspection and just put the lines together, then before the race put the controller in and cable tie it in the cabin so the driver can get to it.

Did you mean AFM or FPR??

Thanks for the tips.

John Stricker
Russell, KS
DOGMA Racing

 

[GrimJack]

The 88 usually has that stupid rubber plug by the firewall. Have a look at the back of the engine on the exhaust side, there should be a hardpipe there about as big around as your thumb, with a short branch off it that's stopped by a plug. The plugs cost ~$1 from the dealer, and they are prone to cracking due to the heat in the area. It's a leftover branch that is unused in the left hand drive USDM market, and in '89 they started making two separate parts, one for RHD and one for LHD, eliminating this little problem spot.

The concern I would have with a used fan / clutch is that it might not be 100% working. As long as the fan is the heavy duty one with 10 blades, it should be fine. The clutch is another story, I'd seriously either go new or search for the rebuild thread - there's some way to refresh the clutch. I've heard it works very well, but I haven't tried it myself. I'd definitely toss the efans, I've rarely seen ones that pull anywhere near the volume you get from the stock setup. New fan shrouds can be had from the dealer for $89, part number 16711-42060.

I'd just mount the boost controller in the engine bay and leave it there for the inspection. Every inspector is going to expect turbo cars to be boosted extra high in the hopes the engine will survive the whole 24 hours anyway.

I absolutely meant AFM. The factory method of adjusting everything to spec involved turning a screw in the AFM that lets more or less unmetered air through into the engine. After getting this set to precisely the correct value, they filled in the top of the screw hole so the end users wouldn't muck with it. The stock ECU can adjust a significant amount, so drilling out the plug and unscrewing this as far as you can without it falling out will give you a bit more leeway on the top end. It will also force the ECU to run at one end of it's allowable range, so I wouldn't suggest it for a road car, but it'll work for your purposes. If you pull off the AFM and look down the intake, you'll see the screw across the bottom.

 

[jstricker]

I absolutely meant AFM. The factory method of adjusting everything to spec involved turning a screw in the AFM that lets more or less unmetered air through into the engine. After getting this set to precisely the correct value, they filled in the top of the screw hole so the end users wouldn't muck with it. The stock ECU can adjust a significant amount, so drilling out the plug and unscrewing this as far as you can without it falling out will give you a bit more leeway on the top end. It will also force the ECU to run at one end of it's allowable range, so I wouldn't suggest it for a road car, but it'll work for your purposes. If you pull off the AFM and look down the intake, you'll see the screw across the bottom.

That's interesting. I just went and looked at one of my spare AFM housings and sure enough, there it was. I also have a Lexus housing and they have one too, although it's huge compared to the stock one. I'm going to have to think about what they're doing there (although I don't doubt what you told me, I just like to understand what's going on). It would seem if we were letting more un-metered air in than the computer thought it would lean things out.........but I'll think about it some more.

I've done tuning, but only on US cars, particularly with the 7730 ECM from GM. That's a whole different beast than what we're dealing with in the Supra's case though. Thanks for the tip and it's appreciated.

I do hope others will chime in as well as far as spares go, and not just engine spares. What I have that I can take:

Spare LSD diff
Spare half-shafts
Spare upper and lower front control arms
Spare rear lower control arms and links
Spare front and rear spindles
Multiple sets of rotors, pads, and at least one spare set of calipers
All of the consumables, of course

We were running about 3 hours of racing with the N/A Supras and fueled with 15 gallons. I'm guessing the turbo engine is going to be more like 2.5 hours or 6 gallons/hr vs. 5 gph without boost. Maybe not even that good. That means for 24 hours of racing we're looking at needing a minimum of 150 gallons of fuel if we last the whole race. This should be fun.

John Stricker
Russell, KS
DOGMA Racing

 

[GrimJack]

I'm going to have to think about what they're doing there (although I don't doubt what you told me, I just like to understand what's going on). It would seem if we were letting more un-metered air in than the computer thought it would lean things out.........but I'll think about it some more.

Actually, you've got it already, that's exactly what it's doing. The thing is, the ECU in closed loop can self correct a bit, and it learns as it goes.

The ECU has 5 settings:
- I think we are much leaner than we should be according to my maps, so I'm adding lots of fuel.
- I think we are a little leaner than we should be according to my maps, so I'm adding a little fuel.
- I think we are in the right place for AFR according to my maps.
- I think we are a little richer than we should be according to my maps, so I'm removing a little fuel.
- I think we are much richer than we should be according to my maps, so I'm removing lots of fuel.

IIRC, a little = 2.5%, and lots = 5%, but I'm a little hazy about those figures.

Normally, the AFM is adjusted so that the ECU sits in the center position. If you adjust that screw a bit, it'll flip over to the next setting. There's absolutely a danger there, as now you're running with a safety margin of 1 in the lean direction, and a safety margin of 3 in the rich direction.

 

[IJ.]

3qt accumulator

 

[jstricker]

Actually, you've got it already, that's exactly what it's doing. The thing is, the ECU in closed loop can self correct a bit, and it learns as it goes.

The ECU has 5 settings:
- I think we are much leaner than we should be according to my maps, so I'm adding lots of fuel.
- I think we are a little leaner than we should be according to my maps, so I'm adding a little fuel.
- I think we are in the right place for AFR according to my maps.
- I think we are a little richer than we should be according to my maps, so I'm removing a little fuel.
- I think we are much richer than we should be according to my maps, so I'm removing lots of fuel.

IIRC, a little = 2.5%, and lots = 5%, but I'm a little hazy about those figures.

Normally, the AFM is adjusted so that the ECU sits in the center position. If you adjust that screw a bit, it'll flip over to the next setting. There's absolutely a danger there, as now you're running with a safety margin of 1 in the lean direction, and a safety margin of 3 in the rich direction.

Makes perfect sense. I hadn't considered the effect of the ECU running in closed loop mode and having it switch maps. Thanks.

John Stricker
Russell, KS
DOGMA Racing

---------- Post added at 08:34 PM ---------- Previous post was at 08:33 PM ----------

3qt accumulator

I agree. I even have one on my Fiero road racer for my Northstar in it. Problem is the money limit. (Unless, of course, you have one you'd sell me for a nice, crisp $50 bill???)

John Stricker

 

[IJ.]

Damn I sold mine to Zumtizzle

 

[shaeff]

Powersteering cooler that's better than stock.

 

[SideWinderGX]

The 88 usually has that stupid rubber plug by the firewall. Have a look at the back of the engine on the exhaust side, there should be a hardpipe there about as big around as your thumb, with a short branch off it that's stopped by a plug. The plugs cost ~$1 from the dealer, and they are prone to cracking due to the heat in the area. It's a leftover branch that is unused in the left hand drive USDM market, and in '89 they started making two separate parts, one for RHD and one for LHD, eliminating this little problem spot.

The concern I would have with a used fan / clutch is that it might not be 100% working. As long as the fan is the heavy duty one with 10 blades, it should be fine. The clutch is another story, I'd seriously either go new or search for the rebuild thread - there's some way to refresh the clutch. I've heard it works very well, but I haven't tried it myself. I'd definitely toss the efans, I've rarely seen ones that pull anywhere near the volume you get from the stock setup. New fan shrouds can be had from the dealer for $89, part number 16711-42060.

I'd just mount the boost controller in the engine bay and leave it there for the inspection. Every inspector is going to expect turbo cars to be boosted extra high in the hopes the engine will survive the whole 24 hours anyway.

I absolutely meant AFM. The factory method of adjusting everything to spec involved turning a screw in the AFM that lets more or less unmetered air through into the engine. After getting this set to precisely the correct value, they filled in the top of the screw hole so the end users wouldn't muck with it. The stock ECU can adjust a significant amount, so drilling out the plug and unscrewing this as far as you can without it falling out will give you a bit more leeway on the top end. It will also force the ECU to run at one end of it's allowable range, so I wouldn't suggest it for a road car, but it'll work for your purposes. If you pull off the AFM and look down the intake, you'll see the screw across the bottom.

Any other options to replacing that hose/plug besides dealer something? Come to think of it, that, one of the two TB hoses and the lower rad hose are the only ones I haven't replaced.


+1 on the fan clutch rebuild, mine worked a lot better after I refreshed it with the 3000 cst oil. I also found out mine is an N/A fan clutch despite it being a turbo car...I can't win.

 

[GrimJack]

Any other options to replacing that hose/plug besides dealer something? Come to think of it, that, one of the two TB hoses and the lower rad hose are the only ones I haven't replaced.


+1 on the fan clutch rebuild, mine worked a lot better after I refreshed it with the 3000 cst oil. I also found out mine is an N/A fan clutch despite it being a turbo car...I can't win.

I've heard of some people pinching the pipe shut and welding it. I really have no idea how well that would work, my knowledge of welding is really weak.

 

[Moy]

Powersteering cooler that's better than stock.

a stock turbo oil cooler would work well for this, just stick it behind the grill (between the nose panel and bumper).

 

[jstricker]

I've heard of some people pinching the pipe shut and welding it. I really have no idea how well that would work, my knowledge of welding is really weak.

It will work fine and I've done it myself on other applications. Put the line in a vise and squeeze it as tightly closed as you can then bronze it shut (I wouldn't weld, I bronze anything I'm trying to keep from leaking in general). It will last several lifetimes. I went and looked at my lines after you posted originally and that's exactly what I intend to do with that pipe. The less rubber under the hood the better.

John Stricker
Russell, KS
DOGMA Racing

---------- Post added at 06:21 AM ---------- Previous post was at 06:19 AM ----------

a stock turbo oil cooler would work well for this, just stick it behind the grill (between the nose panel and bumper).

OK, why? We've never had any issues with our PS oil foaming or getting hot in the NA cars and they had no cooler at all. I realize the "cooler" for the Turbo PS is just a length of tubing in front of the radiator, but if it works why complicate things?

John Stricker
Russell, KS
DOGMA Racing