A Plan for your Consideration and Discussion

[jstricker]

It's time to visit the oracle that is the 7M-GTE forum here at SM for some thoughts from the village elders (not necessarily referring to age but experience).

I am in the final planning and assembly of the engine for our Lemons car. Two things are paramount:

1) Longevity
2) Budget

Both of these take precedence over horsepower, so keep that in mind as you make your comments if you could, please.

The plan I have now is the following build. Basically, a stock bottom end but freshened uup with Clevite bearings. The crank is pristine and I'll probably polish it, but other than that a thorough cleaning is it. The rods will get ARP rod bolts. I found a set of cheap ARP main studs as well as a set of ARP head studs.

The block is at the machine shop now getting decked (the engine had a BHG) with the front cover in place. The head will also get decked and checked for cracks. I'll grind the valves myself as I have the tools for it and the work I do on the car doesn't count against the cost. I have the helicoils for the exhaust studs so they're going in right away. I have 3 spare heads so there is no shortage of shims to properly set the valve clearance. Head gasket will be a MLS, again for cost reasons.

I've read the debate here and on other forums about the value or lack thereof to use the NA Intake cam. Everything I've read runs from the range of 1) it does little to no good to 2) it can give about a 10 hp pickup. Nowhere did I read that it hurt power although it may soften up the bottom end a tad. That's not really a concern since the Lemon's races are always rolling starts and once on track the engine will probably not say anything under 3,000 rpm. With that in mind (and because I have 3 extra NA intake cams) I'm going to use one.

I have a Lexus AFM with the Supra electronics so I plan to use that to avoid fuel cut for as long as possible. I also have a 3" downpipe that came with some other parts I bought. Although I'd like to use 550cc injectors the budget rules that out. It does not rule out the use of an adjustable FPR, though, or a manual boost controller.

Again, for the sake of longevity, I want to limit the boost from stock levels to a maximum of 12 psi. The EGR will be gone and I do plan to add a sandwich block on the oil filter to run an aftermarket oil cooler since I found one for about $50. Not as good as a full re-route, I know, but better than stock.

The ignition will be stock with the ground mod done. The injectors will be checked (by me, I have a test rig) for balance and a good spray and that's about all that can be done with them.

OK friends, what am I forgetting? I can check and degree the cams in and have an idea to adjust the timing in a limited fashion to get it dialed in. So what else can I do to get this ready given what I've already told everyone?

Thanks in advance for the input.

John Stricker
Russell, KS

Edited to add:

I'd be interested in hearing what the CRANK HP estimates of this might be. I would think in the area of 260-275 which is at least 50-60 over the NA 7M's we've been campaigning. Other opinions??

 

[Poodles]

Use the GTE cam, you lose power by using the NA cam. It's the exact opposite of what you think, it makes the bottom end come on hard but chokes the top end.

Running a lexus AFM without 550's is going to be a tuning chore. If you can borrow a wideband and get it dialed in with the AFPR and the AFM screw you should be set. As it's a race car, run an open downpipe with a turn down (undercoating is flammable so need to direct it down or out the side).

 

[jstricker]

Use the GTE cam, you lose power by using the NA cam. It's the exact opposite of what you think, it makes the bottom end come on hard but chokes the top end.

Running a lexus AFM without 550's is going to be a tuning chore. If you can borrow a wideband and get it dialed in with the AFPR and the AFM screw you should be set. As it's a race car, run an open downpipe with a turn down (undercoating is flammable so need to direct it down or out the side).

I have a wide band that will datalog. That said, will I be ahead (in your opinion) with keeping the stock AFM and selling the Lexus in the classifieds to offset some cost? I have no problems going that way as long as we can get in that HP range I mentioned in my first post and avoid fuel cut. If it were you putting this together with the parts available, which way would you go?

In the parts we bought as a lot there was also a K&N filter in a stock housing as well as a simple round adapter with a very large K&N cone filter. The cone filter would take some adaptation to get mounted (not a big deal) but the stock shape filter would, of course, be a stock bolt in. Will the K&N stock size filter flow the air required without issue to make close to 300 crank HP? I have thought about modifications to the stock filter hat as well, but haven't looked at it that close yet.

The downpipe open brings up another question, we do have sound rules. How loud IS a 7MGTE right out of a downpipe? The turbo will quiet it somewhat, but I have no idea how much having never heard a turbo'd Supra without a muffler. I plan to use side exit just ahead of the rear wheels as the exhaust has to exit behind the driver's compartment. I can go into that in more detail in another post but even with a muffler is should be similar in back pressure to a 3" straight through system with 2" X 4.5" oval exit.

Thanks for the thoughts, hope others chime in as well.

John Stricker
Russell, KS

 

[jdmfreak]

I was making about 10 lbs of boost with my stock ct 3"downpipe and no boost controller with the stock supra afm

Sent from my DROIDX using Tapatalk

 

[Poodles]

On the issue of sound, open downpipe is pretty loud, and I have no idea what the sound rules are so it's hard to say if you'll be fine or not.

You could try a stock AFM, up the boost and see if you get the power you want without hitting fuelcut. The only other issue you guys might have is going to be boost leaks, what are you guys doing for intercooler piping?

 

[jstricker]

On the issue of sound, open downpipe is pretty loud, and I have no idea what the sound rules are so it's hard to say if you'll be fine or not.

You could try a stock AFM, up the boost and see if you get the power you want without hitting fuelcut. The only other issue you guys might have is going to be boost leaks, what are you guys doing for intercooler piping?

I have a couple of full sets of stock piping but I was really planning on some ghetto bent muffler tubing to minimize the connections. I read somewhere about someone that used PVC which in theory should work well with glued joints but a search turned up nothing about it. IOW, I'm open to suggestions..............

I appreciate the information. I'm actually leaning now to the stock AFM and selling the Lexus one. Simpler is better, almost always.

John Stricker
Russell, KS

 

[Poodles]

You could go with stock piping if needed, I'd just upgrade the clamps (if you can find cheap t-bolts). The two spots that are bad are the pipe right off the turbo and the coupler that goes to the throttlebody. Pipe off the turbo bakes and crumbles, and the coupler at the throttlebody isn't made as well as the rest and fails (usually on the bottom where you can't see the split :rofl

Have you thought about cooling for the car?

 

[jstricker]

You could go with stock piping if needed, I'd just upgrade the clamps (if you can find cheap t-bolts). The two spots that are bad are the pipe right off the turbo and the coupler that goes to the throttlebody. Pipe off the turbo bakes and crumbles, and the coupler at the throttlebody isn't made as well as the rest and fails (usually on the bottom where you can't see the split :rofl

Have you thought about cooling for the car?

Thanks for the tips, I'll check those couplings and I do have T bolts (I'm a diesel mechanic) and can probably find more relatively cheap.

Cooling I'm debating. I need a radiator. I can get a stock replacement in brass for cheap. I have an excellent stock shroud, the two a/c fans that work, and a 10 blade stock fan with turbo fan clutch. I may take the clutch apart and refresh the oil in it because I think it just takes silicone shock oil, at least that's what most of them take. I've thought about one of the EBay aluminum radiators but that's going to stand out like a sore thumb at tech inspection even if I paint it black. I was also planning on using the stock automatic transmission cooler in the radiator for the power steering cooler to get it out of the front of the car.

Again, any thoughts are welcome.

John Stricker

 

[IJ.]

Radiator shouldn't make a difference for an inspection....

 

[jstricker]

Radiator shouldn't make a difference for an inspection....

Yeah it does. I should probably explain the procedure.

The rules say that except for certain specific things that have to do with safety the car can't cost more than $500. That includes the price of the car. Now you can sell stuff off the car and that money can go to the fabrication so that helps. Also anything you build yourself or do yourself doesn't count, but if you hire it done then the labor you pay for has to count.

Now there are two inspections. The first is a safety inspection. They check the cage, harnesses, seat, wheels, tires, brakes, fluid leaks, master cutoff, etc., etc., just like any other safety/tech inspection. Once you get a sticker for THAT you move on to the BS inspection where you try to talk your way past Judge Phil. Judge Phil is no dummy. He knows cars and he knows BS when he sees and hears it. He knows that the cars are costing more than $500 but his job is to keep it within limits (his own mind you) and within the spirit of the rules.

If he decides you spent more than his limit you get docked laps. Sometimes a lot of laps. I say a Spec Miata docked 250 laps down at Houston one time because you can't buy a roller SM chassis for under $4K and Judge Phil damn sure knows it.

Radiators are not considered safety equipment. If an obviously new radiator is in the car he's going to expect to see a receipt. It will count against the $500. It needs to be offset somehow.

In our case we got lucky. I found the car in basically one piece for $250 and have the receipts to prove it. We also found a pickup load of Supra parts with LOTS of spares for $170. This provided us with a lot of needed parts but even more important things that have some value as trade bait or to sell. Now you know why I'm so insistent to try to keep the outward appearance of the car stock. It's also why I'm going to turn my own solid sub-frame bushings out of $30 worth of surplus aluminum. It's why I bought used KYB shocks and struts. Instead of using coil-overs I'm going to cut the springs two full coils and use $8 spring rubbers from Speedway. We found some ST bars in the pickup load of parts so they're getting used. I'm going to build different end links.

I think you get the picture. Frugal is the word here and making the most out of what you have. Our team is lucky. One of the drivers has a body shop so he's handling the painting and using the cheapest paint imaginable but since he's painting it himself all it will cost against the car is the cost of the paint. I do race car fabrication part time out of my shop and have a Lathe, Mill, Drill Press, Plasma, Mig, Tig, oxy/acet, four post hoist, four corner scales, suspension setup tools, tubing bender (bent the cage myself), full diagnostic equipment, etc. Another driver owns his own shop in down by Wichita and has numerous contacts in the aviation industry that let us score dirt cheap surplus mil-spec parts and surplus/scrap aluminum.

All of this helps but we have to be very, very careful because this is a NEW car to Judge Phil. He will have never seen it before and believe me, he will question EVERYTHING, especially since it's a turbo car. All I can do is document everything and hope he buys it but it helps to stay very close within the rules even when the rules don't make sense. For instance, there's a lot of fueling going on at one of these races. It takes a significant amount of time particularly since while you're fueling you cannot have anyone in the car, changing drivers, working on the car, or anything else. In fact, the only people that can actually be touching the car are the fuelers and they have to be in SFI firesuits and helmets. This leads to a lot of spilled fuel and wasted time so I built a 40 gallon fuel cart with an electric 12 gpm pump. Pull up the cart, take off the cap, less than 90 seconds later the cap is back on and we haven't spilled a drop.

Other teams bitched. It was unfair, they cried. It was unsafe, we all know you can't have an electric pump moving gasoline, right? So this year, they banned it. Exactly 5 teams in Lemons had a cart like ours (and 3 of them I sent the plans and equipment list to them so they could copy ours because I really do think it's that much safer), but it's still banned. now we have to dump fuel in out of a can. SO, I spent last night with the filler neck off the tank. I drilled out the unleaded restrictor and pulled the flapper out of the bottom. I increased the size of the vent hose to 3/8" and ran it through a fuel filter and a roll-over valve. I tested it and it will take a full 1" stream of fuel out of a can now, before it wouldn't. It's more dangerous, it's more work, and it's a PITA, but it's the rules so it's what we have to do.

John Stricker
Russell, KS

 

[Poodles]

Could cobble together a bigger radiator from another car as well.

If you can hunt down a 91/92 power steering cooler it has better cooling, but it's still in front. Could also use one off another car (it's on the return, so low pressure).

 

[IJ.]

Sorry was thinking legality for on road....

Does it make a difference if it's a Freebie zip nada type deal??

 

[jstricker]

Sorry was thinking legality for on road....

Does it make a difference if it's a Freebie zip nada type deal??

That depends on what you can talk Judge Phil into. As I said, he knows cars and he knows BS. IF, let's say, you get "Joes Radiator Service" to give you a new radiator for nothing and "Joes" isan't on the side of the car as a sponsor or anything, he just wants to help out............Maybe that might fly. However if "Joe's Radiator Service" is on your car and he gave you a free radiator then a fair market value for that radiator is assessed against the car. If you do manage to find a sponsor the best thing to do is to get cash and use it for travel expenses.

From the Lemons website:

WHY NOT CHEAT ON THE $500 LIMIT?

Because our BS-Factor judging panel will dock you one lap for every additional $10 it thinks you spent. It's also a claiming race, meaning the organizer can buy your car after the race for $500 if he thinks you've been cheating.

Now while it is a claiming race to my knowledge they have only claimed one car, ever. That was last fall when some guys showed up with a Mustang (I believe) that looked ratty as hell and had a $10,000 Pratt and MIller race engine in it. Most of the really blatant cheaters end up as either the People's Curse award and getting crushed or simply spend most of the race in the penalty box watching other cars go around and around.

It's very hard to explain or put in print what is allowed and what isn't, you kind of have to be there and get a feel for the thing.

John Stricker
Russell, KS