20mpg+ Build
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Car: 1989 Formula
Engine: 305
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20mpg+ Build
I have a 1985 iroc with a 1987 350 2 port tpi motor.
The motor is completely pulled apart and ready to be machined.
I'll most likely just bore it out 30 over.
My original plan was to put some vortec heads on it off a 96-98 silverado and a mild cam.
I know its a 350 and all but is 20 mpg a possibility?
Besides good tune, exhaust, and air filters. What are the best build parts for 20mpg?
Is there any way to keep power with a little economy?
Thanks in advance
The motor is completely pulled apart and ready to be machined.
I'll most likely just bore it out 30 over.
My original plan was to put some vortec heads on it off a 96-98 silverado and a mild cam.
I know its a 350 and all but is 20 mpg a possibility?
Besides good tune, exhaust, and air filters. What are the best build parts for 20mpg?
Is there any way to keep power with a little economy?
Thanks in advance
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Car: 1988 Gta trans am project 1-1/2
Engine: 86 4 bolt main cammed sbc 355 hsr
Transmission: 89 wc bw t5
Axle/Gears: Bw 9 bolt (3.27) pbr 11in
Re: 20mpg+ Build
Yea do a stock tpi build an u should see 20+ mpg make sure the torque converter lock up works if auto car if standard u could go with a lower rear end gear ratio like 2.73's 3.08's etc etc
#3
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Re: 20mpg+ Build
second that call....my stock 305 TPI with 3.08 rear end does 26 mpg highway all day long. 20mpg city.
that said replacing the stock fuel injectors to the Bosch ones from SouthBay was a big part of that. Before I was at 19 mpg highway.......the old ones were that tired.
that said replacing the stock fuel injectors to the Bosch ones from SouthBay was a big part of that. Before I was at 19 mpg highway.......the old ones were that tired.
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Car: 1971 Camaro
Engine: 427
Transmission: TKO600
Axle/Gears: 3.73
Re: 20mpg+ Build
One of the goals of my build is 20+mpg.
Should not be too hard to reach ,with a light right foot.
Should not be too hard to reach ,with a light right foot.
#5
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Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: 20mpg+ Build
yea i decided to just port the tpi heads instead. (college budget) ill do some research into the bosch fuel injectors as well. Also im converting the car to a manual with a T5.
Glad to hear that such a fun car can still get 20+ mpg.
Also that comp 500 cam, does that add mpg? or just the best cam you can really get w/o hurting mpg?
Glad to hear that such a fun car can still get 20+ mpg.
Also that comp 500 cam, does that add mpg? or just the best cam you can really get w/o hurting mpg?
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Car: 1971 Camaro
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Re: 20mpg+ Build
I can't say if the 500 cam would improve milage.
I sent Comp my specs and said I wanted good performance and milage, they suggested the 500 cam based on that.
I sent Comp my specs and said I wanted good performance and milage, they suggested the 500 cam based on that.
#7
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Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: 20mpg+ Build
I emailed them too a couple days ago. Still waiting for my response. I'm following your re re re build page to kind of guide mine.
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Car: 86 IROC
Engine: 350 Vortec TPI
Transmission: 700R4
Axle/Gears: BW 3.27
Re: 20mpg+ Build
I have the 501 cam with vortec heads and I would say highway doing 70mph I get about 25mpg. This is going to the track, making 5 passes and driving home after. General mixed driving, I would say I get about 20-22.
#10
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Re: 20mpg+ Build
You want a 350 and 20mpg+?
Put a stock 350TPI with a T56. Done.
Do it with a LT1.
Do it with a 5.3L Gen3 swap too.
Just about any T56 or T5 equipped 350 with a mild cam and good tune will do 20mpg+ easy if its running right. Gearing is KEY.
My LT1 with a T56 got 32mpg steady state highway cruising to Road America, and on the way back with the 0% ethanol gas WI has I got 34mpg.
Put a stock 350TPI with a T56. Done.
Do it with a LT1.
Do it with a 5.3L Gen3 swap too.
Just about any T56 or T5 equipped 350 with a mild cam and good tune will do 20mpg+ easy if its running right. Gearing is KEY.
My LT1 with a T56 got 32mpg steady state highway cruising to Road America, and on the way back with the 0% ethanol gas WI has I got 34mpg.
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Engine: Boosted LSX
Re: 20mpg+ Build
26mile one way. Im guess If I actually get a tune it would do a little better.
Right now its still on stock tune, so deff. not great being all a.i.r , egr is deletes along with 2 o2 because of the long tubes.
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Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: 20mpg+ Build
ok ended up getting some vortec heads ($200) and im not sure what i should really do with them... but im not going to port them. I just need to figure out what is good to do to the heads and what type of cam to get to break 300hp and still get 20+mpg. Any suggestions?
#13
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Car: 86 Camaro Z28
Engine: 305 TPI
Transmission: TH 700R4
Axle/Gears: 2.73
Re: 20mpg+ Build
get a new intake manifold because your stock TPI manifold wont bolt up. scoggin dickey makes one for around 400 bucks.
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Car: 1991 Christine Z28
Engine: RV Cam and Intake 350 SBC
Transmission: 5speed
Axle/Gears: 3.08 ls Posi
Re: 20mpg+ Build
stock 305 tpi 122k miles, shorter belt(no a/c, no a.i.r.), t5, 3.08 gears. cruising at 80mph on the highway I got 26mpg. With headers, t56, and a tune that could EASILY be 30+ mpg.
I'll let you know how much the 350 gets on the highway with the corvette tune and headers when I get time to do some highway driving. I'm going to guess 28mpg though.
I'll let you know how much the 350 gets on the highway with the corvette tune and headers when I get time to do some highway driving. I'm going to guess 28mpg though.
#15
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: 20mpg+ Build
I have a SDPC TPI intake for those heads. Its new never installed but box is long gone. PM me if intrested
#16
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Car: 86 Camaro Z28
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Axle/Gears: 2.73
Re: 20mpg+ Build
Hope the OP see this. cause i dont know if hes done his homework on vortec heads, but if he has and already has a manifold man i would be very appreciative to be next in line
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Car: 86 Camaro Z28
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Transmission: TH 700R4
Axle/Gears: 2.73
Re: 20mpg+ Build
well out of respect I'll wait till the op says yes or no, or until the next time you go out there. I'll definitely come out, honestly i have never been and i would love to bring the family!
#19
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Car: 1989 Formula
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Re: 20mpg+ Build
I work at advanced auto parts so i can get the edelbrock vortec manifold manifold for 20% off. http://www.summitracing.com/parts/edl-3817
Is the sdpc intake better though?
I just sold my 083 tpi heads and intake manifold for $150 so theres no turning back now.
Is the sdpc intake better though?
I just sold my 083 tpi heads and intake manifold for $150 so theres no turning back now.
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Car: 86 Camaro Z28
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Re: 20mpg+ Build
hell you could get more than 20% discount from just ordering online.. if you look up online discount codes you can get nearly 40% discount... i used to work there and it was funny that they offered us 20% discount and online you can get more than that... and really theres no difference between the two, they are just made to go on vortec heads, both work with big tube runners, so if ya dont have those consider getting one of the kits on ebay (someone on here may have one) for getting the dents out of your runners, supposedly they have a stage 3 kit that also widens the tubes out to the size of big tube runners, i hear good things about siamesed runners as well but i think you sacrifice torque for horsepower somewhat that way- they look neat though
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Car: 1989 Formula
Engine: 305
Transmission: T-5
Axle/Gears: 3.45 1LE Disc LSD
Re: 20mpg+ Build
I have the vortec heads
I will have the edelbrock vortec adapter
Also I will have a mild cam.
Can i use a t-5 transmission? or do i have to save up for a t56?
I have no clue what my pounds of torque will be...
I will have the edelbrock vortec adapter
Also I will have a mild cam.
Can i use a t-5 transmission? or do i have to save up for a t56?
I have no clue what my pounds of torque will be...
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Car: 1991 Christine Z28
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#23
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Re: 20mpg+ Build
I was really impressed with my 217k 91 L98 car coming from Kingman AZ to West Jordan UT. (540 miles) I Filled up in Kingman and When I got to St.George I still had about a touch over a quarter of a tank, I could've easily made it to Cedar City but I decided to fill up early. When I got to West Jordan I still had a 1/4 of a tank left. I don't know how to do the math but it did awesome.
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Car: 1991 Christine Z28
Engine: RV Cam and Intake 350 SBC
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Re: 20mpg+ Build
I was really impressed with my 217k 91 L98 car coming from Kingman AZ to West Jordan UT. (540 miles) I Filled up in Kingman and When I got to St.George I still had about a touch over a quarter of a tank, I could've easily made it to Cedar City but I decided to fill up early. When I got to West Jordan I still had a 1/4 of a tank left. I don't know how to do the math but it did awesome.
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Car: 1991 Christine Z28
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#29
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