Bundera Engine Conversion- COMPLETED!!

Post by **Singo17** » Thu Sep 18, 2003 4:47 pm

BUNDERA wrote:Well the system is in place. 2.5" system with the straight through muffler. Sounds awesome when u give it a gutful and nice and quiet if u are just cruising.

The engine now runs alot smoother and has heaps more power than it did with no exhaust!

I now need to get a bonnet scoop and I also need to work out an intercooler..think I will front mount it.. needs a bonnet scoop to get some air on the engine as it gets quite warm after a while..

Took it on a local track yesterday...I love Goodyear MTR's they kick arse! (Off Jeffery's Track) Those side lugs rock!

I will definatly get some pics soon.

Regards,
Nick

GU ones are cheap put two on

Post by **robbie** » Thu Sep 18, 2003 5:16 pm

raise the back of the bonnet up (next to the windscreen) so you let hot air escape, run a front mount.. and you're sweet

dont know why it runs better with an exhaust, turbo's don't like any backpressure so you must be trippen :finger:

Post by **slowhilux** » Thu Sep 18, 2003 7:51 pm

DONT PUT A BONNET SCOOP ON !!!!

The reason for this is the air entering the scoop is taking away air pressure from the front of the car, ie, the radiator. This in turn will cause the motor to overheat. These motors run pretty hot, especially on the exhaust side, just cos it is so compact and restrictive in that area.

Even putting the bonnet scoop on backwards wont help. If you tie a piece of string to a scoop thats mounted backwards, the string will get sucked back in the scoop. So what does that tell you about which way the air is flowing?? Only properly engineered scoops work, like factory built performance cars (Ferrari, Porsche, etc.)

Phill

Post by **robbie** » Thu Sep 18, 2003 10:37 pm

so you're telling me the drag cars with hornet style bonet scoops are a waste of money?

why do you think the string gets sucked in, cause its sucking the cool air from outside in..

sorry, but I think you have just confused yourself dude

Post by **Singo17** » Thu Sep 18, 2003 10:51 pm

slowhilux wrote:DONT PUT A BONNET SCOOP ON !!!!

The reason for this is the air entering the scoop is taking away air pressure from the front of the car, ie, the radiator. This in turn will cause the motor to overheat. These motors run pretty hot, especially on the exhaust side, just cos it is so compact and restrictive in that area.

Even putting the bonnet scoop on backwards wont help. If you tie a piece of string to a scoop thats mounted backwards, the string will get sucked back in the scoop. So what does that tell you about which way the air is flowing?? Only properly engineered scoops work, like factory built performance cars (Ferrari, Porsche, etc.)

Phill

So the air going into the scoop passes over the engine and then exits the radiator at the front causing overheating.

Post by **slowhilux** » Fri Sep 19, 2003 3:08 pm

Ding ding ding....wrong!! Drag cars (mainly carby V8s) use a bonet scoop for their air intake for the motor, nothing more nothing less. If you see a rotary or efi drag car with a bonnet scoop, its there for wank value. They are not running for long enough to warrant trying to get hot air out from the engine bay.

As for the air pressure subject, a radiator works at its optimum when whe it is the ONLY item at the front of the vehicle that recieves airflow through it. Start taking away the pressure that flows through the radiator, by adding shit like brake ducts and bonnet scoops, it isnt going to perform its job as well as it could. Sorry, but i cant explain it any more simpler than that.

The string item. OK, so the cold air is being sucked back into the engine bay. So where does it go? Not very far. Remember we are trying to get hot air OUT of the engine bay, not give it more air to heat up.

Honestly, the best thing you can do for the cooling, is use a bigger radiator.

Oh, and if you are still worried about hot air floating around the bay, buy a couple of bildge pumps. Wire them up and mount them so that they are facing in a direction so as to push the hot ambient air down underneath the car and out of the bay.

Post by **Skip** » Fri Sep 19, 2003 5:16 pm

Good news gents, got the Bundy registered today, all I had to do was change the drivers mirror from convex to flat. Will put my original convex mirror back on now as it is electric. Ill take some pics, but will need someone to host them, if anyone wants to give me a yell.

BUNDERA: Man you must have given that firewall a good old whacking. My rear turbo is going to foul the bit that juts out by a couple of inches. Looking at my import, there should be stacks of room for an intercooler the size of a supra one in front of the radiator. Also did the exhaust guy run the exhaust down the side of the car?

Just out of intrest, the front brakes are pretty good on this thing, the discs are at least 310mm with 2 spot calipers

, unfortunatly it didnt come with LSD diffs, the axle code is G 144, meaning 4.875 ratio, 4 pinion free wheeler, tranny is R151f.

Let the conversion nightmare begin!!!!!!!!!

Post by **dumbdunce** » Fri Sep 19, 2003 6:58 pm

most diesel bundys came with G145 Limited Slip! there is some argument as to whether the '4' on the end of the axle code might mean electric locker, or open 4 spider carrier - but I reckon you'd know if you had a locker.

if you want a limo carrier let me know I've got a couple lying around.

the R151F is the pick of the bundy gearboxes, lower first gear and almost bulletproof - same gearbox as current 105 series diesels!

Post by **Thor** » Fri Sep 19, 2003 11:50 pm

Just throwing in my 2c worth on the scoop idea.. had a look for a site a saw a while ago but couldn't find - had stats (he used sensors around the engine bay) from a wrangler owner who was looking to reduce temps under bonnet. apparently it was very bad to let too much air in scoop style (something to do with when it was a cold day the engine wouldn't run properly after being designed to operate at a certain temp). however it did warrant cruiser 40 series style fins on each side of the bonnet. i believe he ended up using fins off a pontiac.

Post by **Singo17** » Sat Sep 20, 2003 2:05 am

slowhilux wrote:Ding ding ding....wrong!! Drag cars (mainly carby V8s) use a bonet scoop for their air intake for the motor, nothing more nothing less. If you see a rotary or efi drag car with a bonnet scoop, its there for wank value. They are not running for long enough to warrant trying to get hot air out from the engine bay.

As for the air pressure subject, a radiator works at its optimum when whe it is the ONLY item at the front of the vehicle that recieves airflow through it. Start taking away the pressure that flows through the radiator, by adding shit like brake ducts and bonnet scoops, it isnt going to perform its job as well as it could. Sorry, but i cant explain it any more simpler than that.

The string item. OK, so the cold air is being sucked back into the engine bay. So where does it go? Not very far. Remember we are trying to get hot air OUT of the engine bay, not give it more air to heat up.

Honestly, the best thing you can do for the cooling, is use a bigger radiator.

Oh, and if you are still worried about hot air floating around the bay, buy a couple of bildge pumps. Wire them up and mount them so that they are facing in a direction so as to push the hot ambient air down underneath the car and out of the bay.

So if he had a rear mounted radiator he could have bonnet scoops....

Yeah do that

Post by **slowhilux** » Sat Sep 20, 2003 8:31 am

If he had a rear mounted radiator, there would be no need for a scoop, cos the hole where the radiator was in the engine bay would be the biggest and best damn "scoop" you could have!! Imagine the airflow through a 600x600mm hole in front of the motor. Not that this would help f%@$ all doing slow trail work, this is where the bildge pumps come into their own, constantly pushing air out regardless of the outsied air/road speed

Phill

Post by **Singo17** » Sat Sep 20, 2003 10:04 am

Sorry Slowhilux I am only pulling the piss.

Ignore posts

Post by **MUSS** » Sat Sep 20, 2003 12:43 pm

how long did you expect these bilge pumps to last as they are originally made to pump WATER and not air :roll:

Post by **Skip** » Sat Sep 20, 2003 1:38 pm

dumbdunce: excuse my ignorance, but whats a limo carrier?

Good news, ive lined up a bellhousing from Dellow to suit my motor/gearbox combo.

Post by **Singo17** » Sat Sep 20, 2003 3:49 pm

Skip wrote:dumbdunce: excuse my ignorance, but whats a limo carrier?

Good news, ive lined up a bellhousing from Dellow to suit my motor/gearbox combo.

I assume LSD carrier

Post by **dumbdunce** » Sat Sep 20, 2003 6:19 pm

yeah. limited slip. my bad :/

Post by **slowhilux** » Sun Sep 21, 2003 3:35 pm

Singo,
Tis all good mate

So far 2 of these bilde pumps have lasted in a mates turbo MX5 for bout 15months, and still going strong! Considering they run ALL the time, and its his only car, AND it does about 35-40000km a year

Post by **jessie928** » Sun Sep 21, 2003 5:45 pm

to quote slowhilix"
Ding ding ding....wrong!! Drag cars (mainly carby V8s) use a bonet scoop for their air intake for the motor, nothing more nothing less. If you see a rotary or efi drag car with a bonnet scoop, its there for wank value. They are not running for long enough to warrant trying to get hot air out from the engine bay.

As for the air pressure subject, a radiator works at its optimum when whe it is the ONLY item at the front of the vehicle that recieves airflow through it. Start taking away the pressure that flows through the radiator, by adding shit like brake ducts and bonnet scoops, it isnt going to perform its job as well as it could. Sorry, but i cant explain it any more simpler than that.

The string item. OK, so the cold air is being sucked back into the engine bay. So where does it go? Not very far. Remember we are trying to get hot air OUT of the engine bay, not give it more air to heat up.

Honestly, the best thing you can do for the cooling, is use a bigger radiator.

Oh, and if you are still worried about hot air floating around the bay, buy a couple of bildge pumps. Wire them up and mount them so that they are facing in a direction so as to push the hot ambient air down underneath the car and out of the bay. "
------------------------------------------------------------------------------------
What so an efi v8 engine doesent need cold air?
Of course a drag car is running for long enough to expell hot air, you cant take a stone cold engine and thrash it down the quarter mile, well in actuall fact you can, but dont expect much life/performance from it.

Heat soak is your enemy before a drag/race whatever,

a hole in the right place on your bonnet does heaps to expell air, especially at the most important time, when moving slow. this is called natural ventilation.... because heat rises and will travel to the highest point to be expelled, ( this is usually the rear of the bonnet near the hinges so vent it there or lift up the rear of the bonnet.

air pressure to the front of most card doesent get concerntrated in one point only, there are many points in the front of 4wd's that creare positive pressure of varying strength. Adding a brake duct or a bonnet scoop will not take pressure away from the radiator, it will just make use of wasted air that would have run underneath or over the car.

a bigger radiator is not always the cure for overheating, airflow over and around your engine. you can have the biggest and badest radiator, but if you got nowhere for the hot air to escape when your going very slow ( when there is no airpressure around) you will have overheating dillema's

Next time your on the trail, take a laser temp gauge and point it at various parts of the bonnet when the trucks temps up. The hottest part is where you should open a big ass hole!

When the cars moving along enough for the air to be pushed around the engine and out thrugh the transmission tunnel it doesent matter if air is sucked in through the hole in the bonnet.

JEs

Post by **slowhilux** » Sun Sep 21, 2003 6:31 pm

Agreed heatsoak is your worst enemy, hence the reason why ALOT, not all, drag cars are NOT warmed up before a run. To this extent, most "drag" motors (whether it be rotary, V8, 6 or whatever) are comonly known as "grenade" motors, ie, more time/effort/money spent on outright power than reliability. Sure with this in mind the motor may last 6-12 months of racing, BUT hoew much of this time is actually spent running, be it on the dyno or track? Stuff all, compared to a daily driver or even hypo street car (which is usually a compromise between power/reliability).

If i was Nick, i honestly would not worry bout a bonnet scoop (personal experiences AND testing), cos when driving it on the road, it will have more than enough airflow through the bay to not worry bout heatsoak. But once i got to a trail, doing slow-arse low range work, hell, take the bonnet off! Switch the thermos on full time, and let all the air escape with no restrictions.

Geez, i got one of these motors in a 26 year old celica, with bigger turbos, custom manifold/dumps etc etc NO heatshields (factory have about 8 around the turbos), and it doesnt get that hot under the hood (all exhaust parts are ceramic coated tho). Only time it gets warm is when i manage to get the manifold/exhaust housings and dump pipes to glow red :finger:

, THEN she gets a bit toasty!

Post by **BUNDERA** » Sun Sep 21, 2003 9:21 pm

Well it looks like there are a few disagreements over the bonnet scoop idea.

I am still not sure what I am going to do regarding that.

I am definatly going to get a front mount made or severly modify the one i have.

I am still running the original suspension and will be fixing the suspension for good in the next few weeks.

I will get off my arse and take some pics of the finished thing tomorrow I prommise.

Regards,
Nick

Post by **MUSS** » Sun Sep 21, 2003 10:48 pm

bout bloody time too :finger:

Post by **jessie928** » Mon Sep 22, 2003 2:27 pm

your adding different parts into the eqaution, like ceramic coating....
I would like to see your underbonnet/engine temps without ceramic coating and in a 4wd doing trail work at high rpm , turbo's spooling and NO airflow to keep it cool.... i dont like the chances of your 16" davis craig pumping enough air there....try all this is 30+ degree heat and now your talking cool of times....

when were talking drag cars, i didnt realise were talking about throw away engines.....

any engine you want to last, has to be warmed up and KEPT at a specific running temperature for it to live a long and healthy life, ESpecially a turbocharged engine running at elevated boost levels.

Jes

Post by **slowhilux** » Mon Sep 22, 2003 6:37 pm

Jess,
I understand where your coming from. But i doubt that when you are doing slow trail work, you are not actually using most of the rpm range. I'd say with a 1G, low 1st, you wont need to rev it past 3400-3600rpm (the have soft cut at 7200rpm). Im sorry about bringing the ceramic coating into the equation, but it is the BEST single way to keep under bonnet temps down.

I didnt actually mean for this to turn into a debate like it has. I originally tried to just offer my own experiences( from actual testing), but i spose i went about it the wrong way.

Nick, BTW, if you decide to turn the boost up, factory boost cut is at 14.7psi (1bar exactly), so set it at bout 13.8-14psi ON A HOT DAY. This allows for the extra boost created on a cold night....

Phill

Post by **jessie928** » Mon Sep 22, 2003 6:54 pm

Phill,

Debate?

maybe i'm typing it the wrong way, this is just a e-mail disscussion list and thats what were doin, were throwing suggestions, idea's thoughts around, and its just that

dont take it the wrong way

Jes

Post by **slowhilux** » Tue Sep 23, 2003 3:18 pm

yeah when i wrote debate, i couldnt think of anyother word, but what you said is what i meant

Phill

Post by **dumbdunce** » Wed Sep 24, 2003 9:03 am

it's a MASS DEBATE!

Post by **BUNDERA** » Wed Sep 24, 2003 3:52 pm

dont mention that word infront of jake!! ":finger: :rofl:

"

Post by **BUNDERA** » Wed Sep 24, 2003 3:53 pm

posting up pics now...

Post by **robbie** » Wed Sep 24, 2003 4:01 pm

hurry up

Post by **BUNDERA** » Wed Sep 24, 2003 4:09 pm

here are some pics..

Dont bag the airducting both... the air intake and between the turbos and inlet manifold.

I am going to mount the airintake in the space on the pass side where the original one was fitted. As for the intercooler I may not bother as I am looking at getting a MWB or SWB Cruiser in late december (Diesel) for my trip 2 the cape next year..

Nick

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Bundera Engine Conversion- COMPLETED!!

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