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joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

I had always planned on starting a v8 hybrid project but not so soon. I was at the gas pump several days ago and noticed that my normally aspirated carrera body 924s has been getting a consistant 20mpg. It does this every winter, dropping from about 23mpg in the summer months, to worse mileage on the winter grade fuel. Sometimes it falls to 19. It is irritating to get such mileage from a 150hp 4 cyl. This led me to a craigslist find that was too good of a deal to pass up, so now long story short this is sitting in my garage.

It is a 1997 aluminum head chevy lt1 with 85k miles. with aluminum heads it weighs about 80 lbs over the newer ls1. Stock horsepower I believe to be around 300 but I am not a chevy man and am still doing alot of reading and learning.

I will be keeping the transaxle system, but there will be a very solid running 2.5 for sale in the near future.

Black Forest racing installed a lt1 383 stroker with somewhere near 500 RWHP in a 951 and claimed that the transaxle took season after season on the race track without a problem of any kind. Unmodified lt1s have been getting around 30mpg on the highway, so I am hopeful that this project will produce a cheaper to run, more reliable and more powerful car.
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87 924s
88 924SE gone
447 hp cgt clone
87 924S gone
84 944 sold
83 944 sold
89 turbo S LSD, ABS etc
86 951 white rocket
85 944 sport everything.
84 944 sold.
87 944 sold

Sigurd · Posted: Fri Nov 25, 2011 12:45 pm Post subject:

Nice project! Looking forward to seeing pics of the progress. The weight distribution shouldn't be to out of whack either, about 100lbs more in the front, right?
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'77 924

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

Lizard · Posted: Fri Nov 25, 2011 5:08 pm Post subject:

Sorry to burst your bubble, but unless you install a OD assembly into the TT (requiring cutting it all up), or you install the matching transmission and drivetrain you will never see better fuel economy.

If you convert to a programmable engine system you can do a lean burn and get WAY better fuel economy.
I did this with an 86.5 928S engine and went from 20-22mpg to 35mpg.
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3 928s,

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11724 Location: PacNW

I dunno, the 951 trans has a pretty high 5th/Final.

Joe, you using Renegade parts?
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

I have a lsd tranny with the super tall 5th gear from the early 944 that I am going to use. As far as adapting it in, I will probably use a c5 bellhousing and make my own adapter plate. Even if it gets the same mileage, I cant argue with double the horsepower.
_________________
87 924s
88 924SE gone
447 hp cgt clone
87 924S gone
84 944 sold
83 944 sold
89 turbo S LSD, ABS etc
86 951 white rocket
85 944 sport everything.
84 944 sold.
87 944 sold

bnoon · Posted: Sat Nov 26, 2011 2:55 am Post subject:

There are some nice tuning options for the LT1 engines out there. You will have no problem getting better MPG out of it in stock or modified configurations. I had a '93 TA with 4:10 gears and 400 horse to the wheels and got 29 MPG highway out of it. You will no doubt have a better final drive than that car did with your 5 speed.
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'80 924 Turbo - SOLD!
1986 Porsche 944 Turbo - SOLD!
Porscheless

Joes924Racer · Posted: Sat Nov 26, 2011 4:20 am Post subject:

Nice. Good choice on parts.
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Sigurd · Posted: Sat Nov 26, 2011 4:58 am Post subject:

ideola · Joined: 01 Oct 2004 Posts: 15548 Location: Spring Lake MI

Regarding weight, I don't know how the 2.0L compares to the 924S, but the 931 DIN curb weight was just over 150 lbs. heavier than the normally aspirated 924, and given the lighter gearbox, it's a good bet that most of it was due to the added components in the engine bay. I don't think 100 or so pounds will be too terribly bad...
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erstwhile owner of just about every 924 variant ever made