Twin M90's under a firebird hood
#51
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Car: 86 berlinetta 92rs gfx
Engine: 4 bolt 384 stroker
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Axle/Gears: 87 iroc 9 bolt
#52
Re: Twin M90's under a firebird hood
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
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
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.
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...
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...
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Car: 88 GTA
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#55
Re: Twin M90's under a firebird hood
cool built....actually I have been thinling how cool it would be just to look at.......but then again either nobody is doing it for a reason or somebody did it (you!!).
I am saving this stuff for a "someday" project
So what kind of effect would these show on a stock 5.7L LS1 ? or would I need to change things around to reduce compression.
If u had a Ls1 and where looking for a couple stock SC what year cars woud you keep an eye out for on ebay or JY ?
I am saving this stuff for a "someday" project
So what kind of effect would these show on a stock 5.7L LS1 ? or would I need to change things around to reduce compression.
If u had a Ls1 and where looking for a couple stock SC what year cars woud you keep an eye out for on ebay or JY ?
#56
Re: Twin M90's under a firebird hood
My blowers are from Ebay. They are the Tbird units
Im not sure how these will work with a L98, much less a LS1. Future plans 'may' include a iron 6.0L, but dont count on seeing that for a few seasons if ever
This isnt a project for the feint of heart
Im not sure how these will work with a L98, much less a LS1. Future plans 'may' include a iron 6.0L, but dont count on seeing that for a few seasons if ever
This isnt a project for the feint of heart
#60
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Car: 85 Camaro IROC
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Re: Twin M90's under a firebird hood
you have inspired people...
http://www.youtube.com/watch?v=MZ05_...ayer_embedded#
http://www.youtube.com/watch?v=MZ05_...ayer_embedded#
#61
Re: Twin M90's under a firebird hood
you have inspired people...
http://www.youtube.com/watch?v=MZ05_...ayer_embedded#
http://www.youtube.com/watch?v=MZ05_...ayer_embedded#
IDK how he was inspired by him? that was done before this project started.
It inspired me though.
#63
Re: Twin M90's under a firebird hood
DUDE! And you went and criticised my alternative LT1 swap while putting this thing together?
It's almost identical in concept to the setup I was designing for my friends Porsche 944 (minus 1 blower) before he decided to do an LSx swap.
We were going to mock everything up out of MDF then mill the bracketry out of 1/2" aluminum from the scrap metal store. Put it all together like an Ikea end table lol. Before that it was supposed to go on my Mazda but I went turbo instead.
I didnt read the whole thread but why wouldnt you use a blower kit for the 1G sbc and plumb it with EFI? The smaller (122ci) kits go for around 2K. Some porting and fab work can make one of the old school blowers work nicely, an intercooler between the blower and manifold is doable too.
Thats only slightly less displacement than your total displacement, the rear intake and bypass offer some significant advantages over the older blowers but I'm not so sure this setup will put out a lot more power in the end.
Never the less good luck, it's the type of thing I'd love to do for a friend.
It's almost identical in concept to the setup I was designing for my friends Porsche 944 (minus 1 blower) before he decided to do an LSx swap.
We were going to mock everything up out of MDF then mill the bracketry out of 1/2" aluminum from the scrap metal store. Put it all together like an Ikea end table lol. Before that it was supposed to go on my Mazda but I went turbo instead.
I didnt read the whole thread but why wouldnt you use a blower kit for the 1G sbc and plumb it with EFI? The smaller (122ci) kits go for around 2K. Some porting and fab work can make one of the old school blowers work nicely, an intercooler between the blower and manifold is doable too.
Thats only slightly less displacement than your total displacement, the rear intake and bypass offer some significant advantages over the older blowers but I'm not so sure this setup will put out a lot more power in the end.
Never the less good luck, it's the type of thing I'd love to do for a friend.
#64
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Re: Twin M90's under a firebird hood
got any updates for us pocket?
#65
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Car: 1991 Trans Am GTA
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Re: Twin M90's under a firebird hood
DUDE! And you went and criticised my alternative LT1 swap while putting this thing together?
It's almost identical in concept to the setup I was designing for my friends Porsche 944 (minus 1 blower) before he decided to do an LSx swap.
We were going to mock everything up out of MDF then mill the bracketry out of 1/2" aluminum from the scrap metal store. Put it all together like an Ikea end table lol. Before that it was supposed to go on my Mazda but I went turbo instead.
I didnt read the whole thread but why wouldnt you use a blower kit for the 1G sbc and plumb it with EFI? The smaller (122ci) kits go for around 2K. Some porting and fab work can make one of the old school blowers work nicely, an intercooler between the blower and manifold is doable too.
Thats only slightly less displacement than your total displacement, the rear intake and bypass offer some significant advantages over the older blowers but I'm not so sure this setup will put out a lot more power in the end.
Never the less good luck, it's the type of thing I'd love to do for a friend.
It's almost identical in concept to the setup I was designing for my friends Porsche 944 (minus 1 blower) before he decided to do an LSx swap.
We were going to mock everything up out of MDF then mill the bracketry out of 1/2" aluminum from the scrap metal store. Put it all together like an Ikea end table lol. Before that it was supposed to go on my Mazda but I went turbo instead.
I didnt read the whole thread but why wouldnt you use a blower kit for the 1G sbc and plumb it with EFI? The smaller (122ci) kits go for around 2K. Some porting and fab work can make one of the old school blowers work nicely, an intercooler between the blower and manifold is doable too.
Thats only slightly less displacement than your total displacement, the rear intake and bypass offer some significant advantages over the older blowers but I'm not so sure this setup will put out a lot more power in the end.
Never the less good luck, it's the type of thing I'd love to do for a friend.
#66
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Car: 1987 IROC-Z Camaro
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Re: Twin M90's under a firebird hood
Gear lube is the nastiest fluid in a car (especially burnt), barring non-DOT5 brake fluid, because it's only nasty for it's paint eating properties.
Pocket, you might want to look into ABS Powerbrake's electric booster setup. It lets you mount the master on the firewall, and you use an electric hydraulic pump instead of a vacuum or hydroboost. You can remote mount it anywhere, but the closer, the better.
Pocket, you might want to look into ABS Powerbrake's electric booster setup. It lets you mount the master on the firewall, and you use an electric hydraulic pump instead of a vacuum or hydroboost. You can remote mount it anywhere, but the closer, the better.
#67
Supreme Member
#68
Re: Twin M90's under a firebird hood
burnt gear lube makes my butthole pucker up, sooo nasty.
pocket i got a couple questions for u...
is the Z06 MAF a direct bolt in for a stock GM firebird MAF wire harness? and what is the purpose besides being larger/flowing more air?
and what does your "tuner" state about tuning for this beast? from what ive heard its better to tune with a SD setup than a MAF.... but ive also heard that the MAF is a easier plug and play system and will make it easier since it directly measures the air (not applying this to a forced induction setup). but doesnt the Forced induction change the purpose of the MAF? since its no longer sucking the air under normal atmospheric pressures and the intake is now pressurized? basically just saying now that there is more air per cubic inch vs a NA motor wouldnt the MAF calculations be off?
im planning to run dual t3/t4 turbos and i want to keep my MAF system and tune it. tuning is fun i just want it to work which is why i ask. i love the MAF system and im sure GM figured it was best bc it went from MAF to SD and back to MAF for EVERYCAR STILL BEING BUILT!
pocket i got a couple questions for u...
is the Z06 MAF a direct bolt in for a stock GM firebird MAF wire harness? and what is the purpose besides being larger/flowing more air?
and what does your "tuner" state about tuning for this beast? from what ive heard its better to tune with a SD setup than a MAF.... but ive also heard that the MAF is a easier plug and play system and will make it easier since it directly measures the air (not applying this to a forced induction setup). but doesnt the Forced induction change the purpose of the MAF? since its no longer sucking the air under normal atmospheric pressures and the intake is now pressurized? basically just saying now that there is more air per cubic inch vs a NA motor wouldnt the MAF calculations be off?
im planning to run dual t3/t4 turbos and i want to keep my MAF system and tune it. tuning is fun i just want it to work which is why i ask. i love the MAF system and im sure GM figured it was best bc it went from MAF to SD and back to MAF for EVERYCAR STILL BEING BUILT!
#69
Re: Twin M90's under a firebird hood
It is a truck 5 wire MAF. You need to cut the old MAF and IAT pigtails off and attach the truck MAF connector for it to work. It is larger and more accurate
Im confident in the tuners abilities. He suggested MAF for what Im doing, so I put the MAF back on. I read on tech about maxing out the MAF after so many PSI, so I was going to drop it. Hes tuned beasts much wilder than this combo and said MAF was better
We will see
Im confident in the tuners abilities. He suggested MAF for what Im doing, so I put the MAF back on. I read on tech about maxing out the MAF after so many PSI, so I was going to drop it. Hes tuned beasts much wilder than this combo and said MAF was better
We will see
#71
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Car: 91 Z28, 2000 T/A
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Re: Twin M90's under a firebird hood
It is a truck 5 wire MAF. You need to cut the old MAF and IAT pigtails off and attach the truck MAF connector for it to work. It is larger and more accurate
Im confident in the tuners abilities. He suggested MAF for what Im doing, so I put the MAF back on. I read on tech about maxing out the MAF after so many PSI, so I was going to drop it. Hes tuned beasts much wilder than this combo and said MAF was better
We will see
Im confident in the tuners abilities. He suggested MAF for what Im doing, so I put the MAF back on. I read on tech about maxing out the MAF after so many PSI, so I was going to drop it. Hes tuned beasts much wilder than this combo and said MAF was better
We will see
#72
Re: Twin M90's under a firebird hood
It's rare for MAF's because of the shape but VAF's as used on older Toyotas and Mazdas commonly fail above 15 PSI.
#73
Re: Twin M90's under a firebird hood
If you are talking about the LS1 MAF, they make an adapter for it so you don't have to hack your harness. I have the harness and a truck MAF if you are looking for one.
#74
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Car: 91 Camaro RS
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Re: Twin M90's under a firebird hood
Man, this is insane, you really got your act together, i cant wait to see this in action
#79
Re: Twin M90's under a firebird hood
Anything new?
Im going to do this build now. I saw you said that the GM units are bulky but I cant find any T bird eaton m90s at my local yards.
MORE PICS PLEASE.
Im going to do this build now. I saw you said that the GM units are bulky but I cant find any T bird eaton m90s at my local yards.
MORE PICS PLEASE.
#81
Re: Twin M90's under a firebird hood
In the pics did you already relocte the brake booster?
Also what are the dimensions of the T bird M90. I have a copy of the GM version (well atleast thats what I think it corresponds too)
Also what are the dimensions of the T bird M90. I have a copy of the GM version (well atleast thats what I think it corresponds too)
#82
Re: Twin M90's under a firebird hood
Deleted it attempting a manual brake conversion. Even with the additional mechanical advantage from moving the mount point upwards, the brakes are ridiculously hard. Im going to either build a remote system or incorporate a tiny import pancake booster/master
Dimensions
http://www.capa.com.au/eaton_m90data.htm
Dimensions
http://www.capa.com.au/eaton_m90data.htm
#83
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Car: 1987 pontiac firebird
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Re: Twin M90's under a firebird hood
why not use hydroboost brakes? get the booster from an 94-95 chevy astro van and the master cylinder from a 4th gen f body it will bolt rite in place and is a lot smaller. the only part that needs to be modified to convert to hydroboost is the linkage. the one from the astro will be 3/4 of an inch to short. but that aint hard to fix.
#84
Re: Twin M90's under a firebird hood
Distance from the firewall to the master flange is what Im trying to minimize
Hydroboost systems are smaller in diameter than vacuum boosters, but generally very similar in length. Also, I dont have a PS pump any longer
Hydroboost systems are smaller in diameter than vacuum boosters, but generally very similar in length. Also, I dont have a PS pump any longer
#85
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Car: 84 Z28 / 88 Trans Am / 87 base
Engine: L69 H.O. / 468 BBC / 2.8 v6
Transmission: 89 700R4 / TH375B / 700R4
Axle/Gears: 3.73 open / 3.23 posi / 3.42 open
Re: Twin M90's under a firebird hood
Am I seeing this correctly? Are the plates at the front of the block which hold the SC's also your front engine mounts?
#87
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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
Deleted it attempting a manual brake conversion. Even with the additional mechanical advantage from moving the mount point upwards, the brakes are ridiculously hard. Im going to either build a remote system or incorporate a tiny import pancake booster/master
Dimensions
http://www.capa.com.au/eaton_m90data.htm
Dimensions
http://www.capa.com.au/eaton_m90data.htm
many people in the pro-touring scene run non-assisted brakes with no problems on a semi dd car.
you will need a new master cylinder, and new calipers at a bare minimum.
the calipers from a power assisted car will not work.
if you are trying do do it on the cheap, start raiding junk yards for parts from older 80's cars with non-assisted brakes.
#92
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Car: 84 SVO
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Re: Twin M90's under a firebird hood
I peer in every now and again..
Nice to see folk still enjoying the old Malibu and eatons.
I've been busy building a SVO..
Nice to see folk still enjoying the old Malibu and eatons.
I've been busy building a SVO..
#95
Re: Twin M90's under a firebird hood
Splitting it up and selling it off for school
Intake is sold. One blower on my DD, other sold. Just trying to get by
Will go 6.0 LSx and some combo of blowers in the future though, dont worry. Chassis isnt going anywhere
Intake is sold. One blower on my DD, other sold. Just trying to get by
Will go 6.0 LSx and some combo of blowers in the future though, dont worry. Chassis isnt going anywhere
#96
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Re: Twin M90's under a firebird hood
awwwwww this was a sweet *** build man, stay in school kids and you wont have to abandon projects like this!!!!
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