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89 740 NA project.

hk 40

Banned
Joined
May 15, 2011
Location
RTP, North Carolina
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I am putting one back together for my son. We got it running good with all the lights working and the other day it just died on him and wouldn't crank anymore. I ran the self test on the ignition and fuel system and everything came back 111. I then looked at the timing belt and it is real loose worn with threads showing and covered in oil. It's pretty likely it's slipped, so I'll replace that and see if she runs again. I love this car as it sits at 220k and was still running really well. It needs an exhaust but it is so easy to work on who would care that owns anything new. I was hoping to source a header and decent exhaust. We haven't thought about making it a turbo even though I have the reverse dome mahle pistons out of a b21ft. but I think for now I'd just like us to have a nice NA tune then go from there. Any Ideas on a good header and cone filter?



Regards,
Hubert
 
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It was definitely the timing belt. Turned the crank before the cover was fully removed . No action on the belt, it's gone. At least 10 teeth are totally absent from the belt :) At least I know we will run again. Now im looking for a good 4 inti 1 NA header. Any leads?​

TIA,
Hubert
 
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KL Racing has a header, but $ is likely better spent in other areas first. The stock manifold and header pipe are not that bad.

It's all shot though and the resonator and muffler are gone so I'd rather just replace it all for cosmetics as much as performance. The engine has been gone thru already and is truly mechanically sound. It is running like a clock so a nice exhaust and cold air induction it would seem would be a good start. Of course the end game will likely be a turbo but I don't want to start at that with a turbo exhaust header. I was thinkin SAM may have something for better NA performance. Nothing would goto waste as I have several of the red block vehicles at different stages. If you don't mind please share a link to the KL header. I really wish there was some individual bell mouthed velocity stack style port injection units for the redblock??? Also the heater tube from the exhaust manifold to box stock air filter flapper assembly... there has to be something a bit cooler looking and more functional than that. :oops:

Regards
Hubert
 
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Yeah "naw" she wont run like that....:-P Don't know if anyone can in the attachment see the pieces of the old belts teeth sitting beneath the camshaft gear. The bet stopped in
just that position too.

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Nevertheless I installed a new timing belt and we have action.
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While I was in there visual inspections of car show its pretty sound. I went ahead and pressure washed the undercarriage oil pan etc. It is looking really good to see the REDBLOCK with no dirt or solvents on it :wtf:. The child is gone to work in the vehicle and I may never get it back to finish my vision for him.....:lol: Seriously though Im going to see what we can do with this old girl....​
 
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One thing I always have to have in my cars is music so a nice stereo is part of my vision for him. In the front doors will be pioneer separates . TS-C1301 which are 5 1/4 inch driver and 1 in dome tweeter which will actually be Skar audio 1" titanium's. I already have a Sony deck in there with aux in for media but I plan to retrofit a tablet right in front of the main air vents like a modern vehicle and run a pioneer blue tooth standalone DSP processor. It features all the high end adjustments any audiophile would need and runs from the Tablet or your phone through a pioneer app. In the rear deck I'm actually going to mount 8 inch drivers beneath the rear deck instead of on top this way we only have to perforate the rear deck on location versus cutting big holes in the read deck of the vehicle car. I want alot of sound with very little visually apparent for all the sound it produces. I want a OEM or rather stealth install. For the subs I'm going to build a aperiodic ally damped infinite baffle. They are very cheap on the pockets and very compact. For about a yard (100 dollars) this is the power u get. More than enuf for a good 4 channel delivery in "BETSY" Im carrying these Skar Audio and Taramps in our stereo shop. HiTech Audio.


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2020 razor

Max Power 2,000 Watts
RMS Bridged @ 4Ω 500W x 2
RMS Power @ 2Ω 250W x 4
RMS Power @ 4Ω 190W x 4​
 
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A little theory on aperiodic enclosures. For people that may be interested in putting a very nice sounding stereo in their old 740's

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Tuning an aperiodic enclosure. The theory is the air trapped in the sealed enclosure (acoustic suspension) mechanically fights back like a shock absorber what the amp want to do with the linear motor physically so the electrical impedance peaks at the linear motors resonant frequency driving down the amplifiers delivery of power on the low end. Dynaco found out in the 60's that simply cutting a hole in the enclosure and controlling the enclosures breath through a aperiodic material like R-25 (pink panther fiberglass) halved the seen impedance ( double the power ) at resonant frequency. It creates much better delivery of the low end an creates a relatively flat response that rolls of nicely down to the resonant frequency. To the ears this enclose deliver a much smoother response than the acoustic suspension system( a sealed box). I will leave a sketch of the basic design as it will be very easy to set up in the SQUARE Volvos. This delivers excellent and accurate reproduction of the low end of the music. Plays much deeper than any sealed enclosure with a much smoother roll off. It also take up very little trunk space. In fact you'll retain about 90% of it with this style enclosure which is a goal for a more stealthy installation.​

Regards
Hubert
 
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The problem with good sound and the factory locations is obvious in this car. The speakers are too low in the door and biased to the driver to have a sound stage in front of the windshield. I don't want to use kick panels so the only other way is to try a center stage and digital time alignment. With respect to not adversely bending sound the coaxial is the best bet. If u put the tweeters on the pillars and speakers in the door from a separates set you truly create more sound alignment issues. It may sound okay to the ears but you wont have a highly defined sound stage with good imaging and stereo separation. This leads me to rethink the component set and opt for a bi amplifiable coaxial. This would allow you to keep the factory grills and appearance while having a good sound stage hard to ruin with non equidistant alignment issues. The pioneer DSP has the dual 31 band 1/3 octave eq. digital time alignment and fully adjustable 3 way crossovers with 24db slopes. If you stay with the 5 and1/4 drivers creating small aperiodic enclosures for the door may be possible. The OEM mounting of the speakers in only the pressed board door panel will never produce quality sound. The speakers need solid mounting to the steel door. This in mind lets build some epoxy glass enclosures. We can accomplish this by building a plug and then vacuum forming layers of glass matt and high temperature epoxy over the plug then popping it out when it is cured. When I get home Ill post the vacuum forming rig and we can start building the plugs for coaxials



Regards,
Hubert
 
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Well it seems we will be getting deeper in it after all. The Radiator hose blew on the child and he drove the car hot till it stopped.:grrr:

The head gasket is blown away on initial inspection. Will be removing the head shortly...YAAY Im thrilled..... :) I had it running really good. No way I'm going to go through all this for natural aspiration so looks like things get interesting alot sooner than I thought. I certainly know what I need in an exhaust now. While I was siting around surfing for ideas I tucked the speaker grills in a crushed blue velvet. The doors are black and charcoal tweed . I think Ill set a contrast with these and the door inserts in this color. The tabs that attach to the red anchors in the door always break so Ill use button magnets and an on location pin to keep them in place. Since it will be disabled for while I guess ill tear the interior all they way down and lay some wiring for the electronics. We need to start piecing together the basic OEM turbo setup. If you know where the basic OEM parts are speread out here, feel free to point me to it in the thread. Around 200-225 hp should be more than enough for the young man who blows head gaskets and possibly blocks... :-P

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Regards
Hubert's
 
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Well I guess ill start taking the head off. Any wagers on if the kid broke my heart or not? Anyway I decided the best way to go about the aperiodic door enclosures was to invert the speaker grills to be the removable backs of the enclosure to load the owens corning 703. We can see that only two trim rigs of 3/4 mdf will basically make the round enclosure depth. It will be no larger than the midbass in diameter and only 2 inches deep if you add a half inch of the ridged fiberglass installation. Ill finish them with a flanged lip that will screw into the steel of the door. The I can sound deaden everything. The speakers will be mounted behind the door panels not just in the doors hard board which is terrible. Because the drivers will be behind the interior door panel the factory grills should easily fall in their place. I will still share the vacuum form process for GFK and CF parts in time.​

Thank you for your time and patience.
Hubert
 
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If no one knew what USD audio used for their world famous Aperiodic enclosures in their worlds finals IASCA cars here it is. Its corning 703 rigid fiberglass board. It comes in varying thicknesses, I share how they are tuned later for those that may not know. Im sure the older Cali boys know about USD audio and their infamous Buick Grand National.​

Regards,
Hubert
 
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I have an Acura I'm currently working on that will have three 12's in an aperiodic enclosure. He loses virtually no trunk speaker and will have plenty of drop. The cone can move fairly easy but it is damped by the aperiodic material and sub sonic and low pass filters. The subsonic filter needs to crossed at the woofers resonant frequency. For tuning that's 1 part. More comes later. A winglet goes in place here to help seal the front from the back before I fill the voids with expandable foam. This separation from trunk to car interior cabin is critical in getting this enclosure to act right.​

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These are the woofers this thing holds. I plan to put at least three 10's in the 740 probably 4. I want some DROP!​

Regards
Hubert
 
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Here is another example of one for 15's. They have to play through this or in front of this from the trunk into the passenger cabin. The screen material was used so this one could be loaded with loose pink panther if I wanted too. It will also look cool with the contrast of the fiberglass against it. It really keeps the material in its place and off the drivers. Both sides have a back with the woofer hole cut out . I have it off so you can see the interior. Two blocks on 2 inch material load in here and the back goes back on. Remember the box volume is infinite(the trunk when closed and all outside when open). The speakers play through this or have to breathe through this from the trunk to inside the car however you want to look at it. When this is tuned correctly a box will never have its low end or transient response.
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Regards
Hubert
 
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Get yourself some old skool RFR3115s and rawk out with that mad drop.

But seriously, glad to see another bass head here :cool:
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Me too. Glad you are here but first comes the long hand of the law. Any wagers if this head is damaged or not?

Im assuming those are rockford numbers. I worked with Hugh Cobb in the late 90's who was their beta tester for years and won the worlds years ago at 0-500 class. Of course with all Rockford Fosgate. I did a nose bleed system when I worked with him which was 6 Rockford DVC 12's in wall in a Chevy cavalier. BIG DROP TRUST. The streets no longer run it really the big name brands. Many are turning to TARAMPS and SKAR audio. The class d has taken over. My amps of choice are any Hifonics from the ZED audio days. The key to the aperiodic is the qts need to be below .45 so typically woofers with big rubber surround are no good especially if the woofers in front versus behind the damper. The dayton audios posted have carbon fiber impregnated into their paper cones. Very strong and very tight. This isnt a setup purely for spl. It is designed for accurate bass reproduction with all kinds of music. It should play classical just as good as rap or rock well below the woofers resonant frequency.

Regards
Hubert
 
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This is what it came out to be with the winglet in place. Of course you could probably fit it better but this will come out nice. Im going to invert the woofers so they are facing the trunk. This way I can put a beauty board over them an only the sharpest eye will realize the trunk is shortened just by a bit in between the shock towers.

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The 7 inch Kenwood multimedia deck that flips out is mounted inside the gutted factory in dash changer. I also polished the trim bezel. We plan to adapt the GPS screen above it to for own needs. I'll likely install a HDMI to composite video so he can run a firestick in the car with his mobile phone hotspot.

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You can see from the trunk how the rigid fiberglass mat will load into each chamber. The final mounting plane will be just in front of these strut towers. That's it as far as the enclosures depth into the trunk. He will have full access to his spare and amp rack. The power wire is 1/0 . The alternator is a 240 ampere. When the cross members go back in there will be no way to quick remove the enclosure without tearing the enclosure and speakers apart.​

Regards,
Hubert
 
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