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#241 Stoffregen Motorsports

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Posted 11 January 2017 - 10:28 AM

HKS used to make the composite steel head gaskets. Don't know if they still do. There is another company that makes them, but I can't think of their name right now. The cool thing about them is that they are reusable and rebuildable, and even adjustable by adding or removing shims to raise or lower the compression ratio.

 

If you can't find one, I would just o-ring the block and bring to the track a few OEM Nissan gaskets. Even the GT motors still use OEM gaskets.

 

Hopefully you're not going to use head studs though as they make head R&R a pain in the ass.



#242 distributorguy

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Posted 11 January 2017 - 12:43 PM

I am using ARP head studs and a Nismo gasket.  ARP nuts are eaier than stock bolts, and we need more strength.  Over 15:1 compression, naturally aspirated.  Its not likely to see even 50 miles between engine rebuilds.  It'll be ok.  Once the motor is certified (if we back-up a record run), and if we fail the whistle test, then we pull the head.  No big deal.  4 hood pins, so that's not in the way, big pop-up tent to work under on the salt.  

 

Guys, when you offer advice, keep in mind this is Bonneville.  Relaxed pace, almost never full throttle to modulate tire slippage, very high compression, never touch the brakes, light load top speed racing with soft shifts.  Durability is only for RPM, not load until peak speed, then the load is wind not traction.  Its boat racing with wheels and salt and even less traction.  Nothing about it is similar to track racing.  



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Posted 11 January 2017 - 02:32 PM

It's drag racing on a 5 mile dirt/salt track.



#244 Stoffregen Motorsports

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Posted 12 January 2017 - 09:20 AM

I guess using studs is the price you pay for such a high CR.

 

I freakin hate em.



#245 distributorguy

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Posted 12 January 2017 - 11:48 AM

I've installed SO many sets...  I like 'em.  Once you figure out how to NOT drop and lose washers and nuts it just becomes a way of life.  

 

Drag racing WOULD be like Bonneville if you needed a 3-4 TON car weight to have enough traction to achieve 200 mph.  That weight also has to be perfectly balanced to avoid spinning out.  Grease the track, then compare drag racing to racing on salt.   :thumbup:



#246 distributorguy

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Posted 18 January 2017 - 02:13 PM

So I think we have a solid plan for the fuel system.  Carter "black" fuel pump - 90 GPH, 7 psi.  Aeromotive ultra-low pressure fuel regulator with 15 psi gauge, 6AN and 3/8" OD stainless lines throughout.  

100 micron filter before the pump, tank modified with a 3/8" OD outlet for fuel supply.  Both vents tied together and Teed into a roll-over valve so the tank can't leak if we crash.  The pump is wired with a relay, 30A fuse, and impact/rollover switch (From a Ford Taurus).  

 

The carbs will be plumbed later with another 30 micron filter either before the regulator or two filters after the regulator to decrease the chance of debris restricting fuel flow.  Each carb gets its own line from the regulator.   Fuel starvation would become insanely expensive, so we're going to avoid that at all costs!!!

 

I've looked at doing a fuel cell, but most are just tanks anyway, with no real protection from a crash.  The factory tank is legal, and in a very safe place, plus it helps balance the driver's weight.  When I have a spare $1000 and no go-fast goodies to spend it on, I'll buy a Fuel Safe.   I've got $400 into this system, using a LOT of parts I already had around.  It could easily reach $2k if I bought all new goodies.  I still may have to buy a higher pressure pump to get the fuel pressure consistent.  We'll see how this plays out with the SUs for now.  The Webers get installed in about 3 months.  



#247 Stoffregen Motorsports

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Posted 19 January 2017 - 12:26 AM

Are the fuel inlet nipples on the SU's removable?  Some of them are not removable, while the threaded fittings vary between applications. Some are BSPT, some are straight threads.

 

Weber DCOE's use a 12mm x 1.5 thread pitch and Mikuni/Solex uses a 12mm x 1.25.

 

It would be nice to plumb -6 all the way to the carbs with fittings instead of hose clamps.



#248 distributorguy

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Posted 19 January 2017 - 05:51 AM

My Webers are 10 x 1.5.  Oddly small, but adequate.  I ordered -6 fittings for them, so they'll be well fed! The SUs don't matter.  They're for low rpm use, only to get the truck aligned, balanced, and work out a few bugs.  Plus they are on the spare engine.  The race motor goes in later with the Weber setup.  Their nipples are press-fit.  Only the older ones have banjo fittings.  



#249 distributorguy

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Posted 25 January 2017 - 01:43 PM

I stand corrected.  12 x 1.5.  Now I get to reorder.  Not sure where I crossed my numbers.  They mic at 11.88.  ???

 

Last night we got the fuel system basically finished for the test motor.  Need to work out throttle return springs and cable, choke cable, and add tranny fluid.  Then we hook up the battery and see what melts down first.   :thumbup:



#250 distributorguy

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Posted 27 January 2017 - 11:46 AM

No melts downs, but the 17 year old jet tubes on my "rebuilt" HS4 SU carbs decided they were never again going to accept fuel pressure.  Who knew fuel lines could fail in only 17 years???  Got the new ones installed this morning.  They hold 3 psi, so the next trick is to crank the motor to get oil pressure, then once the team is around to help and witness the giant blue cloud we fire it up.   :thumbup:   



#251 Stoffregen Motorsports

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Posted 28 January 2017 - 08:35 AM

Yeah, a failure point for sure. You could always upgrade to a thicker hose. But then, these are just for shakedown.



#252 distributorguy

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Posted 28 January 2017 - 08:42 AM

I'll be using Aeroquip hose to the new Webers - AN-06.  No likely failures there.  



#253 distributorguy

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Posted 31 January 2017 - 06:40 AM

Here's a recent pic of the engine bay, just before start-up (hasn't happened yet).  There are a few loose ends including an air gap above the radiator, the distributor wire isn't tied down, the rear carb velocity stack is too close to the brake booster (solid engine mount so they'll never make contact), and the engine breathers are not yet plumbed into an oil separator, just in case.  Feel free to pick it apart and let me know what YOU see that could/should be changed to improve durability, reliability, etc...???  I do not believe we need to run the brake/clutch lines through a heavy steel tube past the flywheel, but I'll research that further.  The stainless fuel line is run outside the frame for just that reason.  The float bowls were wrapped in header wrap prior to just repairing them, but with ceramic exhaust I don't think they'll heat up - that WILL be tested.  The MGB plastic fan will be replaced with an electric pusher on the race motor, or maybe left in place as the shroud adds air resistance to the front end (more air will flow over the truck instead of through it).  May be reverse logic?

 

[/URL]">http://6A180D35-B1F5-4895-A72B-8E9D26AEA731_zps



#254 Stoffregen Motorsports

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Posted 31 January 2017 - 09:30 AM

Looks great.

 

Consider using a master cylinder reservoir relocation kit from Wilwood to get those reservoirs out of the way. I use them often.

 

Also, maybe a stronger battery tie down? Eliminate the j-bolts and fab something so that if you do crash, the battery doesn't fly out of the hood. A gel cell battery would be my choice of battery too.

 

Other than that, it looks really tidy.



#255 distributorguy

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Posted 31 January 2017 - 09:47 AM

You caught my "dangling carrot."  You have to give the inspectors something easy to find, then they get lenient on other simple stuff.  The battery hold-down is a $7 kit from the local farm supply store.  I was going to use a bungee cord to make it more obvious, but that's a little too crude.  I have a full face frame made up for the top of the battery that will be held in place with clevis pins.  I have a couple red-tops around, but the extra weight of a wet cell is a good thing.  Plus they recharge faster and I don't know how big of a power sap running an alternator will be, which is why the field coil is switched on the dash.  

 

As for the master cylinder, I figured next year I'd go to rear disc brakes.  I just don't have the time this year. The Webers will have adequate clearance anyway. I don't know how well the H190 setup is going to hold up, and parts are virtually impossible to find.   New parts don't exist.  When our 2 diffs break, we go to something custom.  At that point I'll need a different master anyway, with rear discs.  I'll probably switch to a Blazer 10-bolt.  For a couple years they used a larger ring & pinion - strong with low drag and disc brakes.     



#256 Stoffregen Motorsports

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Posted 31 January 2017 - 10:53 AM

I used to drive around without a driver's license, so that the officer had something to ticket me for. Worked every time...well almost.

 

Frontal weight is a big consideration, but I having a battery blow up and ruin everything under the hood kills me. But then, if you're not running an alternator, that's probably not a big concern.

 

I didn't realize the H190 was so hard to find parts for. If it were my choice, I'd go with the dropout 9". Being able to remove the diff sure makes things easier when you're not in the home shop

 

How about a Toyota axle? They're light weight (compared to a 9"), there's a million sources of aftermarket parts including lockers, spools, LSD's, gears, bearings, disc conversions, full floating hubs, etc. You could even run a factory electric locker and convert it to cable operation for simplicity. You can score a TRD rear axle out of a Tacoma for $300, at least out here in CA.



#257 Stoffregen Motorsports

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Posted 31 January 2017 - 11:05 AM

Also, the low amount of pinion offset on the Toyota diff means less parasitic power loss.

 

The early 4x4 axles were 55" wide, then 58", and 61" for the Tacoma. And you'd retain the 6 lug wheel pattern.



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Posted 31 January 2017 - 11:52 AM

Why isn't the battery in the far back of the bed where you need the weight. When we ran my sons Nascar clone, we ended up with 400# of lead and needed more.



#259 G-Duax

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Posted 31 January 2017 - 02:20 PM

I don't know how well the H190 setup is going to hold up, and parts are virtually impossible to find.   New parts don't exist.

 

Must not be looking in the right places.

What are you looking for ?



#260 distributorguy

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Posted 01 February 2017 - 06:21 AM

So far I'm still on the hunt for 4.11 gears.  I found a locker.  Bearings are no big deal.  How about a shim kit?  They never came with disc brakes, not that I can't convert it, but its just more time consuming to make brackets, etc...  Toyota is on my radar but I have no experience with them.  I didn't know they had so much aftermarket support.   Ford 9" is out of the question - saps too much power.  I don't have 20 hp to spare. 

 

The battery is up front because I can stack 1/4" steel sheet on the bed floor.  at 75 lbs a sheet, it adds up quick.  There are very few places you can add weight up front.  This isn't Nascar.  Overall weight needs to be high - heavier is better for traction - at all corners.  Add weight until you get great traction (with perfect overall balance), then take enough away so that you can handle the wheel slip.  Most 200 mph cars at Bonneville weigh well in excess of 6000 lbs.