Twin M90's under a firebird hood
#1
Twin M90's under a firebird hood
This topic has been gone over quite a few times with one documented swap of a single M90 under a camaro aftermarket hood
SARURN5 successfully pulled off a swap but it wasnt in a 3rd gen. I need to give him more than just an honorable mention because nearly everything about this project was based off of his work
It begins with a design. This is about the 7th revision
The ducting is rather tricky
It fits
SARURN5 successfully pulled off a swap but it wasnt in a 3rd gen. I need to give him more than just an honorable mention because nearly everything about this project was based off of his work
It begins with a design. This is about the 7th revision
The ducting is rather tricky
It fits
#2
Re: Twin M90's under a firebird hood
I can fit my hand in there
About 1/4" clearance. A little trim is needed
You must go manual brakes or relocate the master/booster
As it sits right now
I cut off the front because i didnt need it. The radiator and IC are going to be angled downward to roughly 45* and moved closer to the crank pulley
The rack is off a Fiero and fitment is perfect, even the stock Fiero shaft fit like it was made to go in there. I got crazy on the notch so the hole is huge, dont worry Ill be cutting the middle section of the K-member out and welding a single tube in between for much needed clearance all around
Eventually I would like to extend my 8 pt cage forward into the engine bay much like this camaro did and remove the strut towers all together
http://i150.photobucket.com/albums/s...ubularnose.jpg
Engine is a stock long block L98 with LT1 intake conversion. SATURN5 ran the crap out of his swap on a stock JY 305. Lets see how long a L98 lasts. I have a race engine in the works for when it does finally let go
Trans is TH350
0411 PCM and harness
Fiero manual rack & pinion
Future projects on this:
Ford 8.8 rear
S10 manual brakes master cyl. I dont like the converted 3rd gen master I have now
C4 front disks
Tubular front conversion
wOot
#4
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Car: 88 GTA
Engine: 305 V8 LB9
Transmission: 4 sp. Auto-4L60
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Re: Twin M90's under a firebird hood
Dang, Jon! No wonder you thought my trans swap on jackstands and all my electronics work was easy!! That's pie compared to what you've done with this. I can't wait to see the BEAST that results from this work!
I still can't believe you do all this in your GRASS front yard and gravel driveway!!!
You da man!!
I still can't believe you do all this in your GRASS front yard and gravel driveway!!!
You da man!!
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Car: 86 berlinetta 92rs gfx
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Re: Twin M90's under a firebird hood
interesting setup, ill be watching this for sure!
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Re: Twin M90's under a firebird hood
Wow, that should be quite the setup. I had one of those blowers on my GTP, 2 should really move some air. Cant wait to hear that thing whine
#10
Re: Twin M90's under a firebird hood
I still can't believe you do all this in your GRASS front yard and gravel driveway!!!
Wow, are you willing to share the models for the LT1? I could really use some of those
wats the expected boost? and power?
Power? Ill be happy is the damned thing runs at all
Cant wait to hear that thing whine
Ive got the Th350 prepped and ready to install. I used the 40 tooth reluctor off a 89 Astro as well as the tailshaft. Im also running into problems with the tailshaft length being 1.5" shorter than the TH350 9" tail. The VSS will read proper, Im just worried if the driveshaft will ride with such little overlap (1/2-3/4") inside the seal. I have tons of spline contact thou so itll likely be ok. It just looks like the DS is about to fall out. Same issues most TH350 swappers run into when attempting to hook up an electric speedo without a JTR unit. In my case they dont sell a cable to 40 pulse per rev adapter so Im up a creek. Im surely not going to buy a cable to 4,000PPM then buy a dakota box to convert it again
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Car: 1984 Z28 HT,2006 2500HD
Engine: 5.7L, 6.6Llbz dmax
Transmission: 700R4, 6 speed allison
Axle/Gears: worn out 3.73 posi
Re: Twin M90's under a firebird hood
good luck changing the plugs but seriously that is freakin sick!
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Car: 1987 Iroc-Z28
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Re: Twin M90's under a firebird hood
subscribing, this is nuts. You need to get a video and let us hear that thing whine, paawweeease
#13
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Re: Twin M90's under a firebird hood
What are you doing for a bypass, did you keep the stock actuator or are you going to run something else?
FWIW, Mike Sitar (Twin Eaton M90 T-bird), and my brother's car have been around with this kind of setup for a long time before Saturn's car. We've even gotten some magazine coverage with my brother's car and it's been invited to run against a bunch of "tuner" cars in MM&FF's "Luxo Barge Shootout"
#15
Re: Twin M90's under a firebird hood
This is a full on drag car, sounds dont bother me. I was just stating my surprise at just HOW loud the things were
No bypass. Im planning 1-2 atmospheric BOV's before the MAF to keep the ducting from blowing apart at the end of each run
Ive been all over the Mike's website about his T-bird. Lots of good info there for anyone who likes fab work, not just relating to blowers
No bypass. Im planning 1-2 atmospheric BOV's before the MAF to keep the ducting from blowing apart at the end of each run
Ive been all over the Mike's website about his T-bird. Lots of good info there for anyone who likes fab work, not just relating to blowers
#16
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Re: Twin M90's under a firebird hood
Speaking from experience, figure out some kind of bypass or you'll never keep the ducting together. Remember, the positive displacement blower will move air whether the throttle is open or closed, BOV's are designed to deal with turbos that build boost pretty close to proportionately with throttle (with a little lag), and airflow can reverse through them. On my brother's car he has the original bypass, which we cutout and welded into some of the ducting, then he setup a manual linkage that only allows it to close when the throttle is WOT. Everything else he tried, even the same bypass just not opened as much of the time resulted in ducting blowing off, even with it only closing at WOT, the rubber elbows in his ducting inflate like balloons if he blips the throttle at idle.
I didn't notice, but are you running MAF or MAP? You may want to also try to figure out some way to mechanically dampen the signal since the lobes on the blower cause distinct pulses in boost that can confuse an ECM and make tuning a bear (data logs on my brother's car are pretty wild looking, one frame will show 11psi, the next will show 0, the next might show 3 or 10... it all depends on where the rotors are in their rotation at the instant the frame happened)
In Mike's case, it doesn't hurt that he's an engineer for Eaton...
I didn't notice, but are you running MAF or MAP? You may want to also try to figure out some way to mechanically dampen the signal since the lobes on the blower cause distinct pulses in boost that can confuse an ECM and make tuning a bear (data logs on my brother's car are pretty wild looking, one frame will show 11psi, the next will show 0, the next might show 3 or 10... it all depends on where the rotors are in their rotation at the instant the frame happened)
In Mike's case, it doesn't hurt that he's an engineer for Eaton...
#17
Re: Twin M90's under a firebird hood
i wouldnt mess with the driveshaft... get a custom one made so u have enough sealing surface at the end of the trans. your gona be making GOBS of power so u'll shred the stocker quickly. id get a MOLY one and call it a day.
this makes me want to throw dual T3/T4 turbos out back by the rear and run em HARDDDD!!!!!
this makes me want to throw dual T3/T4 turbos out back by the rear and run em HARDDDD!!!!!
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Re: Twin M90's under a firebird hood
You are welcome to my garage any time you want to use it...as long as it's not raining.
Can't much blame you there. You're a really generous guy (not to mention wicked smart!), and some people take advantage of that.
You could make anything run... We could put every ghetto fix in the "ghetto fixes" thread TOGETHER, and you could make it run. AND look great.
Take this for what it's worth from me (which isn't a whole lot...but still), but you'll want more overlap on the shaft. One of my buddies blew out his Richmond rear end over the weekend. NOT a pretty sight. One wrong move, and that DS is toast. I'd agree with getting a custom fab or aftermarket.
And Brennan, this man swapped my 700r4 for a 4L60 with my car on home-use jackstands with a home-use jack and ratcheting tie-down straps, and the car runs like a BEAST ( *bowing* We're not worthy!! We're not worthy!!). I wouldn't worry about the plugs.
I tried that a while back trading the long block models for a C4 differential and some trans roughs. Seemed i was sending alot of emails and receiving none back. No offense, but I like to keep the models I spend way too much time on if the reward is nil
Successful swaps has 12-16psi. Im shooting for 14-15 with the stock ford pullies and stock 8' crank. My drive ratio is 2.55 and there are no calculators for estimating twin air pumps
Power? Ill be happy is the damned thing runs at all
Power? Ill be happy is the damned thing runs at all
Ive got the Th350 prepped and ready to install. I used the 40 tooth reluctor off a 89 Astro as well as the tailshaft. Im also running into problems with the tailshaft length being 1.5" shorter than the TH350 9" tail. The VSS will read proper, Im just worried if the driveshaft will ride with such little overlap (1/2-3/4") inside the seal. I have tons of spline contact thou so itll likely be ok. It just looks like the DS is about to fall out. Same issues most TH350 swappers run into when attempting to hook up an electric speedo without a JTR unit. In my case they dont sell a cable to 40 pulse per rev adapter so Im up a creek. Im surely not going to buy a cable to 4,000PPM then buy a dakota box to convert it again
And Brennan, this man swapped my 700r4 for a 4L60 with my car on home-use jackstands with a home-use jack and ratcheting tie-down straps, and the car runs like a BEAST ( *bowing* We're not worthy!! We're not worthy!!). I wouldn't worry about the plugs.
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Re: Twin M90's under a firebird hood
WOW!!! What kind of HP do you think you'll get?
Eric
Eric
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Re: Twin M90's under a firebird hood
This is amazing!
- Can you post some more detailed pics of the scoop devices below the superchargers? I'd like to see how they are shaped and what not.
- What are the mounting plates for the superchargers made out of? I'm assuming it's steel, but what thickness?
- Will the LT1 (or is it a dirty LT4?) flow enough to make the most out of all this fab work?
- If you don't mind me asking, what do you do for a living? Some kind of engineer?
- What program did you use for the modeling? Solidworks?
Please do add a video. I would love to hear how that sounds.
Mike
- Can you post some more detailed pics of the scoop devices below the superchargers? I'd like to see how they are shaped and what not.
- What are the mounting plates for the superchargers made out of? I'm assuming it's steel, but what thickness?
- Will the LT1 (or is it a dirty LT4?) flow enough to make the most out of all this fab work?
- If you don't mind me asking, what do you do for a living? Some kind of engineer?
- What program did you use for the modeling? Solidworks?
Please do add a video. I would love to hear how that sounds.
Mike
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Car: 86 berlinetta 92rs gfx
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Re: Twin M90's under a firebird hood
This is amazing!
- Can you post some more detailed pics of the scoop devices below the superchargers? I'd like to see how they are shaped and what not.
- What are the mounting plates for the superchargers made out of? I'm assuming it's steel, but what thickness?
Please do add a video. I would love to hear how that sounds.
Mike
- Can you post some more detailed pics of the scoop devices below the superchargers? I'd like to see how they are shaped and what not.
- What are the mounting plates for the superchargers made out of? I'm assuming it's steel, but what thickness?
Please do add a video. I would love to hear how that sounds.
Mike
#23
Re: Twin M90's under a firebird hood
This is amazing!
- Can you post some more detailed pics of the scoop devices below the superchargers? I'd like to see how they are shaped and what not.
- What are the mounting plates for the superchargers made out of? I'm assuming it's steel, but what thickness?
- Will the LT1 (or is it a dirty LT4?) flow enough to make the most out of all this fab work?
- If you don't mind me asking, what do you do for a living? Some kind of engineer?
- What program did you use for the modeling? Solidworks?
Please do add a video. I would love to hear how that sounds.
Mike
- Can you post some more detailed pics of the scoop devices below the superchargers? I'd like to see how they are shaped and what not.
- What are the mounting plates for the superchargers made out of? I'm assuming it's steel, but what thickness?
- Will the LT1 (or is it a dirty LT4?) flow enough to make the most out of all this fab work?
- If you don't mind me asking, what do you do for a living? Some kind of engineer?
- What program did you use for the modeling? Solidworks?
Please do add a video. I would love to hear how that sounds.
Mike
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Re: Twin M90's under a firebird hood
How long do you think the motor will last since you mentioned that the one guys 305 did last long?
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Re: Twin M90's under a firebird hood
holy crap, i need a buddy like that living next door to me! i have total faith in this project.
#26
Re: Twin M90's under a firebird hood
It will be a MAF setup. Tuning stuff ill worry about after the physical stuff is finished. I appreciate the heads up and will look for it when the time comes
Ill require a new DS anyways. I highly doubt the stock alumn shaft would survive the first launch, but with the 8.8 rear it definitely wont fit. I have a shop in Winston that does all of our DS work. Hes confident he can make something ill never break
The blower hats are not built yet. The shape is very similar to the stock Tbird units with a bit more curves to cut down on turbulence. I have a CAD model but i doubt Ill build it based on that. Likely Ill just wing it with the welder and my hammer
Front plates are 1/4" plate steel. They double as motor plates which may turn out a nightmare if the blowers twist like crazy and the engine tries to walk a different direction. I took them up to 4,000RPMs (in park, no boost) and they stayed put so we shall see. I did an alternate model using 1/2" alum and the weight difference was 8 lbs. Not enough to bother with the huge cost hike and my inability to weld alum
The intake is a converted LT1. I chose it as a low cost alternative to TPI. The SC's will like the short runners too
Im a Mech Engr student, the program is AutoCAD 2002. I do some stress testing in SW 2007 on the COSMOS addon but those are rare
Several of my friends have a running bet on how long it will live. Most think it will explode upon startup. I do know that if we miss the tune and get any detonation those cast pistons wont be very happy
Emma wasnt very nice during the trans swap. Hope she does better at AF
Blower hat pics
Early design. Notice the holes in the front plates. I havent cut those yet
Essentially I was going to CNC some flanges and form an outlet up to some 2.5" exhaust pipe. This was later dropped since my CNC machine access was cut off when the shop closed down. Now Im using simple 1/4" plate with a semi rectangular hole made via cutoff wheel. You dont want to know how long it takes to cut 1/4" plate. Hell, most people dont believe me when i say I made the front plates with a hack saw and 4 1/2" grinder
A few of the actual undersides with a good shot of the rear brace. I added braces when I first applied belt tension and saw the blowers flex towards the crank about 5*
Ill require a new DS anyways. I highly doubt the stock alumn shaft would survive the first launch, but with the 8.8 rear it definitely wont fit. I have a shop in Winston that does all of our DS work. Hes confident he can make something ill never break
The blower hats are not built yet. The shape is very similar to the stock Tbird units with a bit more curves to cut down on turbulence. I have a CAD model but i doubt Ill build it based on that. Likely Ill just wing it with the welder and my hammer
Front plates are 1/4" plate steel. They double as motor plates which may turn out a nightmare if the blowers twist like crazy and the engine tries to walk a different direction. I took them up to 4,000RPMs (in park, no boost) and they stayed put so we shall see. I did an alternate model using 1/2" alum and the weight difference was 8 lbs. Not enough to bother with the huge cost hike and my inability to weld alum
The intake is a converted LT1. I chose it as a low cost alternative to TPI. The SC's will like the short runners too
Im a Mech Engr student, the program is AutoCAD 2002. I do some stress testing in SW 2007 on the COSMOS addon but those are rare
Several of my friends have a running bet on how long it will live. Most think it will explode upon startup. I do know that if we miss the tune and get any detonation those cast pistons wont be very happy
Emma wasnt very nice during the trans swap. Hope she does better at AF
Blower hat pics
Early design. Notice the holes in the front plates. I havent cut those yet
Essentially I was going to CNC some flanges and form an outlet up to some 2.5" exhaust pipe. This was later dropped since my CNC machine access was cut off when the shop closed down. Now Im using simple 1/4" plate with a semi rectangular hole made via cutoff wheel. You dont want to know how long it takes to cut 1/4" plate. Hell, most people dont believe me when i say I made the front plates with a hack saw and 4 1/2" grinder
A few of the actual undersides with a good shot of the rear brace. I added braces when I first applied belt tension and saw the blowers flex towards the crank about 5*
#27
Re: Twin M90's under a firebird hood
yea i kno how long it takes to cut 1/4" plate. i had to cut a whole bunch of it for my ford 8.8 tq arm mount. it was soooo annoying lol. my arms hurt from the sawzaw and went through blades like every couple of min. then i used a hand jigsaw to cut the center holes that HAD to be PERFECT to fit around the ford 8.8 snout. i tried a air cutter but it took too long.
heres pics
https://www.thirdgen.org/forums/atta...506altered.jpg
https://www.thirdgen.org/forums/atta...511altered.jpg
https://www.thirdgen.org/forums/atta...524altered.jpg
pocket... is the ford 8.8 rear the same as the stocker as far as snout length? im hoping my stock DS will bolt up and is the right length. i kno yours wont work bc the TH350 is a bunch shorter than the 700r4. not sure what your using as the pinion flange? but i used the stock large bolt DIA stock crown vic pinon flange and had to but a neapco ujoint flange for a 1330 to connect to it. the stock DS flange is so weak its ridiculous (stripped out the lock ring since its so thin installing the ujoint). you could prob simplfy it by just getting a pinion flange set up like the stocker from strange/moser and make it easier
heres pics
https://www.thirdgen.org/forums/atta...506altered.jpg
https://www.thirdgen.org/forums/atta...511altered.jpg
https://www.thirdgen.org/forums/atta...524altered.jpg
pocket... is the ford 8.8 rear the same as the stocker as far as snout length? im hoping my stock DS will bolt up and is the right length. i kno yours wont work bc the TH350 is a bunch shorter than the 700r4. not sure what your using as the pinion flange? but i used the stock large bolt DIA stock crown vic pinon flange and had to but a neapco ujoint flange for a 1330 to connect to it. the stock DS flange is so weak its ridiculous (stripped out the lock ring since its so thin installing the ujoint). you could prob simplfy it by just getting a pinion flange set up like the stocker from strange/moser and make it easier
Last edited by customblackbird; 09-11-2009 at 11:12 PM.
#28
Re: Twin M90's under a firebird hood
I havent went yard hopping looking for a 8.8 yet. When I do Ill post another how-to about it. I will be bringing my tape measure as I want a housing thats similar in length to 3rd gen and does not have an offset differential like the explorer units
A 9" tail TH350 uses the stock length DS
Im not sure which yoke Ill go with. I do know it wont be the flat one on most 8.8's
The design will be similar to what yours is except itll have 'wings' going to the axle tubes. This will take the stress off the cast iron ribs (mostly) and put it back on the weldable axle tubes. Id also like some form of top/bottom support possibly from a spacer plate under the rear cover with flanges above/below to run to the snout
A 9" tail TH350 uses the stock length DS
Im not sure which yoke Ill go with. I do know it wont be the flat one on most 8.8's
The design will be similar to what yours is except itll have 'wings' going to the axle tubes. This will take the stress off the cast iron ribs (mostly) and put it back on the weldable axle tubes. Id also like some form of top/bottom support possibly from a spacer plate under the rear cover with flanges above/below to run to the snout
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Re: Twin M90's under a firebird hood
awesome, whtas the ETA on the initial start up?
i wanna hear those things winding out!
i wanna hear those things winding out!
#30
Re: Twin M90's under a firebird hood
the only ford 8.8 that ive found to be close to the 3rd gen is the newer 96 and newer crown vics... they are approximate 1.5" wider on each side so a total of 3" wider than my 3rd gen 9bolt. this will allow me to run 17x10.5 rims with almost 7" backspacing with no issues only prob with the smaller ford 8.8 is the 28 spline axles. But the crown vics have 11.5" disk brakes . inorder for me to swap to 31 spline axles id have to hack off the ends of my axles tubes and weld on larger tube ends for larger bearings (crown vic and every other 8.8 has the axle tubes necked down at the end by the brakes) This would allow the use of the larger ford explorer axle bearings and 31 spline axles.
explorers are the only ones with 31 spline axles (larger bearings as well) but the pumpkin is offset as u said. the reason i made my tq arm bracket like that is so it can be removed. by keeping the tq arm mount attached to only the pumpkin means all the force would be absorbed by the pumpkin which means theres no need to fully weld the axle tubes. if you attach ur bracket to the tubes ur gona have to fully weld the tubes thats all, and it wont be removable.
sounds like ur design is alot like grannys tq arm mount for the RX7s to fit a ford 8.8 in there.
explorers are the only ones with 31 spline axles (larger bearings as well) but the pumpkin is offset as u said. the reason i made my tq arm bracket like that is so it can be removed. by keeping the tq arm mount attached to only the pumpkin means all the force would be absorbed by the pumpkin which means theres no need to fully weld the axle tubes. if you attach ur bracket to the tubes ur gona have to fully weld the tubes thats all, and it wont be removable.
sounds like ur design is alot like grannys tq arm mount for the RX7s to fit a ford 8.8 in there.
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Re: Twin M90's under a firebird hood
customblackbird's 8.8 swap thread has some great info in it. - Sounds as though you're thinking of a mount similiar to mine.
I vividly remember Saturn5's thread(s) about the twin eatons. Mark (83 Crossfire Ta/Silverback) is also a wealth of knowledge on the subject. - I am still working on a M90 fed TPI myself, but it is in my suburban.
As for the heads; although the intake port design becomes less critical with forced induction, a lot of power/efficiency can still be had in the combustion chamber. The exhaust ports need to flow; as although you force the mixture in there, the motor/port is still on it's own for getting the aftermath out.
I'm planning to either keep the eaton bypass as well as utilize a blow-off valve, or I may just run the 1-1/2" in-line procharger bypass valve. You may get by with just the blow-off(s) for a race app, but the bypass valves work great for a street app(power and efficiency).
I will definitely keep an eye on this thread; good luck with it!
I vividly remember Saturn5's thread(s) about the twin eatons. Mark (83 Crossfire Ta/Silverback) is also a wealth of knowledge on the subject. - I am still working on a M90 fed TPI myself, but it is in my suburban.
As for the heads; although the intake port design becomes less critical with forced induction, a lot of power/efficiency can still be had in the combustion chamber. The exhaust ports need to flow; as although you force the mixture in there, the motor/port is still on it's own for getting the aftermath out.
I'm planning to either keep the eaton bypass as well as utilize a blow-off valve, or I may just run the 1-1/2" in-line procharger bypass valve. You may get by with just the blow-off(s) for a race app, but the bypass valves work great for a street app(power and efficiency).
I will definitely keep an eye on this thread; good luck with it!
#34
Re: Twin M90's under a firebird hood
WOWWWWWWWWWWWWWW.............. I have been looking for info on the dual Eaton for about a month now.
I plan on doing the same to my caprice. 92 wagon 358 TPI
I saw mikes first, saturn5 and now you. I hope to be next on the list. Only one other person on the net has a TPI in his caprice wagon Lakeeffect
I found some off a 3800 Bonnie, I know someone on here wants a TPI intake to help me fund my Eatons
I realy like how you ran the blowers. thats different, everyone runs them exit up.
Im not as skilled as you so I belive im going to stick with it up.
Last question, are you blocking off the "NOISE PORT" on the supercharger? Or doing any type of porting?
Please post more pics, and vids I love it.
I plan on doing the same to my caprice. 92 wagon 358 TPI
I saw mikes first, saturn5 and now you. I hope to be next on the list. Only one other person on the net has a TPI in his caprice wagon Lakeeffect
I found some off a 3800 Bonnie, I know someone on here wants a TPI intake to help me fund my Eatons
I realy like how you ran the blowers. thats different, everyone runs them exit up.
Im not as skilled as you so I belive im going to stick with it up.
Last question, are you blocking off the "NOISE PORT" on the supercharger? Or doing any type of porting?
Please post more pics, and vids I love it.
#36
Re: Twin M90's under a firebird hood
I love shiny parts
2-1 intercooler is in from CXRACING (ebay). I flat out LOVE this thing. I googled it extensively before dropping the dollar and most everyone had great results
Next are the BOVs. Most research came from this board about them and there wasnt much complaining. They are advertised as 100% billet but are simply cast and machined extensively. I dont care for the top but the mild steel flanges (cast iron) will likely hit the scrap bin as they weigh nearly as much as the whole valve assembly
I went ahead and built a new radiator support using the stocker and stock dual fans. Its kinda heavy at 40-ish lbs. Ill likely get an aftermarket rad and fan setup if the project is a success. For now these will work. It will mount on short pieces of angle welded to the old frame horns. Body tabs will come off it to better support the nose and hold the hood pins
My truck/Z06 MAF arrived. What a mammoth. With advise from my tuner I changed my 0411 harness from SD back to MAF
Lastly is a comparison of the UMI trans crossmembers for a LSx 4L60E and TH350. Nice pieces
Notice the different directions of the bolt slots and trans mount locations. Im not sure if Ill end up using either one. I plan on making a torque arm that mounts to the crossmember on the twin M90 car and depending on how my exhaust goes I may have to "hump" the LS1 swap car
2-1 intercooler is in from CXRACING (ebay). I flat out LOVE this thing. I googled it extensively before dropping the dollar and most everyone had great results
Next are the BOVs. Most research came from this board about them and there wasnt much complaining. They are advertised as 100% billet but are simply cast and machined extensively. I dont care for the top but the mild steel flanges (cast iron) will likely hit the scrap bin as they weigh nearly as much as the whole valve assembly
I went ahead and built a new radiator support using the stocker and stock dual fans. Its kinda heavy at 40-ish lbs. Ill likely get an aftermarket rad and fan setup if the project is a success. For now these will work. It will mount on short pieces of angle welded to the old frame horns. Body tabs will come off it to better support the nose and hold the hood pins
My truck/Z06 MAF arrived. What a mammoth. With advise from my tuner I changed my 0411 harness from SD back to MAF
Lastly is a comparison of the UMI trans crossmembers for a LSx 4L60E and TH350. Nice pieces
Notice the different directions of the bolt slots and trans mount locations. Im not sure if Ill end up using either one. I plan on making a torque arm that mounts to the crossmember on the twin M90 car and depending on how my exhaust goes I may have to "hump" the LS1 swap car
#37
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Car: 1987 Trans Am
Engine: 355ci L98 soon to be turbo'd
Transmission: 700R4
Axle/Gears: 2.73 posi
Re: Twin M90's under a firebird hood
I'm glad you're actually continuing with this project (most people here start something, but never finish it). Subscribing.
#39
Re: Twin M90's under a firebird hood
I work full time, go to school, build wiring harnesses, fab stuff for friends, and somehow find time for this car. Unfortunately its not as much time as Id like. Im still waiting for a saturday that isnt raining or recently wet as installing transmissions are easier on dry dirt. Of course Ive been saying that for the past 2 months
#40
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Car: 1987 IROC-Z
Engine: 383 with Edelbrock ProFlow EFI
Transmission: TH350
Axle/Gears: 12 bolt 3.73 Eaton posi
Re: Twin M90's under a firebird hood
I work full time, go to school, build wiring harnesses, fab stuff for friends, and somehow find time for this car. Unfortunately its not as much time as Id like. Im still waiting for a saturday that isnt raining or recently wet as installing transmissions are easier on dry dirt. Of course Ive been saying that for the past 2 months
#41
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#44
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Car: 85 Camaro IROC
Engine: 5.7 TPI
Transmission: 700-R4
Axle/Gears: open rear, 3.42 gears
Re: Twin M90's under a firebird hood
wow looking good.
possibly ignorant question, but how do you plan to route the intake ducting?
possibly ignorant question, but how do you plan to route the intake ducting?
#47
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Car: 85 Camaro IROC
Engine: 5.7 TPI
Transmission: 700-R4
Axle/Gears: open rear, 3.42 gears
Re: Twin M90's under a firebird hood
sorry, let me rephrase that.
where will your "cold side" intake be... the non boosted part.
IOW, where will you put your air filters, maf, ect.
i thought the m-90's pulled air in from behind, so it will be slightly difficult to get clean air if this is the case
where will your "cold side" intake be... the non boosted part.
IOW, where will you put your air filters, maf, ect.
i thought the m-90's pulled air in from behind, so it will be slightly difficult to get clean air if this is the case
#48
Re: Twin M90's under a firebird hood
not trying to thread jack, just putting it out there. Might be some others out there who want to this, I was one of them.
I can snag some some L67 3.8 Bonnie superchargers if theyd like saw a few at the yard. LMK quick there are crushing the cars.
Ill take $150 ea plus shipping for them.
.
I was gonna do this swap, and this is the supercharger I was gonna use.
Man please when your done, post vids of it tearing the road up. Its a cool setup dude.
I can snag some some L67 3.8 Bonnie superchargers if theyd like saw a few at the yard. LMK quick there are crushing the cars.
Ill take $150 ea plus shipping for them.
.
I was gonna do this swap, and this is the supercharger I was gonna use.
Man please when your done, post vids of it tearing the road up. Its a cool setup dude.
Last edited by Killerzracing71; 12-11-2009 at 01:58 PM.
#49
Supreme Member
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Re: Twin M90's under a firebird hood
I'm contiually surprized that all of you insist on doing twins... you realize that with some porting and optimizing my brother's car went low 11's/high 10's with a single M90 on a 306(.030" over 302) in a 4 door LTD. Now that he wants to go faster he's building a new setup with a single M112...
For a while I was going to grab the worked M90 and slap it on my k1500, but now I've got other ideas...
If I remember right, the fox mustang axles should be just narrower than f-body axles... that being the case, the mid size fox chassis cars (t-bird, cougar, LTD, Marquis, fairmont...) should be right around an inch or so wider, very close to a 3rd gen, and the ones that had an 8.8 should have either massive drums (11" or so) or disk brakes. That should also put the SN95 axles at someplace between 3rd gen and 4th gen widths.
As far as the large bearings/31 splines... A c-clip eliminator kit for mustang axles will replace the ends of the axles, it's a good time to grab some 31 spline axles and are easy to install.
Personally, I think a Mopar 8-3/4" rear out of the late 60's/early 70's intermediates is a better candidate, it's the right size, can often be had for nothing, has the advantages of a ford 9" housing design with the geometry advantages of a 12bolt/8.8...
Gear lube running down your arm into your armpit or soaked in your hair is MUCH worse... not only is there the yuck factor, but there's the smell that you can't get rid of for days...
For a while I was going to grab the worked M90 and slap it on my k1500, but now I've got other ideas...
the only ford 8.8 that ive found to be close to the 3rd gen is the newer 96 and newer crown vics... they are approximate 1.5" wider on each side so a total of 3" wider than my 3rd gen 9bolt. this will allow me to run 17x10.5 rims with almost 7" backspacing with no issues only prob with the smaller ford 8.8 is the 28 spline axles. But the crown vics have 11.5" disk brakes . inorder for me to swap to 31 spline axles id have to hack off the ends of my axles tubes and weld on larger tube ends for larger bearings (crown vic and every other 8.8 has the axle tubes necked down at the end by the brakes) This would allow the use of the larger ford explorer axle bearings and 31 spline axles.
explorers are the only ones with 31 spline axles (larger bearings as well) but the pumpkin is offset as u said. the reason i made my tq arm bracket like that is so it can be removed. by keeping the tq arm mount attached to only the pumpkin means all the force would be absorbed by the pumpkin which means theres no need to fully weld the axle tubes. if you attach ur bracket to the tubes ur gona have to fully weld the tubes thats all, and it wont be removable.
sounds like ur design is alot like grannys tq arm mount for the RX7s to fit a ford 8.8 in there.
explorers are the only ones with 31 spline axles (larger bearings as well) but the pumpkin is offset as u said. the reason i made my tq arm bracket like that is so it can be removed. by keeping the tq arm mount attached to only the pumpkin means all the force would be absorbed by the pumpkin which means theres no need to fully weld the axle tubes. if you attach ur bracket to the tubes ur gona have to fully weld the tubes thats all, and it wont be removable.
sounds like ur design is alot like grannys tq arm mount for the RX7s to fit a ford 8.8 in there.
As far as the large bearings/31 splines... A c-clip eliminator kit for mustang axles will replace the ends of the axles, it's a good time to grab some 31 spline axles and are easy to install.
Personally, I think a Mopar 8-3/4" rear out of the late 60's/early 70's intermediates is a better candidate, it's the right size, can often be had for nothing, has the advantages of a ford 9" housing design with the geometry advantages of a 12bolt/8.8...
Gear lube running down your arm into your armpit or soaked in your hair is MUCH worse... not only is there the yuck factor, but there's the smell that you can't get rid of for days...
#50
Supreme Member
Re: Twin M90's under a firebird hood