4g61t.org

Yep, that's one of my mechanic helper's Mazda 121.

Man, talk about something that's come a long way. I thought this was going to be one of those threads that will never be finished or one day you'd post some pictures of a partially completed project then the next day talking about how you gave up on it. This is great. Kudos for sticking with it to man! Can't WAIT to see it in action.

I'll certainly second everyone's opinion: this is a seriously impressive project.

May I wade in with some questions?
From an engineering point of view, how did you size the various tube members that form the chassis and develop the configuration? Or are you working to specification provided as part of the racing class?
And (for example) the rocker arms that you are using in the suspension? Or are they off the shelf or did you have them machined to suit?

Continue the good work!
Greg

There is a minimum tube size specified for the main elements of the rollcage, by the regulations. The rest is up to the builder. The rocker arms were machined to my specification.

theoretically you are speaking of just using the crank at that point you would just need taller rods that would give you a 1.9 motor.


the smaller the crank the better it will breathe up top. how ever the torque will be lowered. with that said i do not mean you wont be able to achieve the numbers you want, i'm just putting this information up so that you know what to expect.

if you use the 61t block with your head then yes it would remain 1.6 and you will of course see some gains. the fp30 should be more than enough for the numbers your looking for, i dont know about the torque so much but the power will definitely up there somewhere.


either way good luck with it man, seems very interesting.

Eddie Rosado

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Eddie Rosado

Have you any experience with this type of combination?

nah not my self but all my buddies do this stuff with the hondas all day. and its all the same thing. you can take the k24 crank and swap it for the k20 one.

or you can think of it as the inverse of a stroker build. you are looking at a destroker ?lol


Eddie Rosado

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Eddie Rosado

If you are considering making a de-stroker 4g63 build, I'd highly recommend not waisting your time. It would still barely gain you any displacement as most of it is lost in the short stroke of the 4g61. You would just be adding the extra weight of 9+ mm of iron block and longer rods. Why? The factory 4g61 has a silly rod ratio over 2:1 and will rev higher than the head can flow, even with major work and large cam's.

If you honestly find you need more torque without major displacement increases, go for a 4g67 1.8L block and get back the longer stroke with less piston bore.

I personally think the setup you have will be great as long as you keep the rev's up. You will make very similar peak hp to a 2.0L, usually about 1000 rpms later. If the car is geared properly with the weight advantage, I don't see you having any problem smoking some 4g63's.

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Turning a 4g61t into 1595 cc's of FURY!
10.995 @ 134.44 - http://www.youtube.com/watch?v=bZXvcvzuWGQ

SOLD to the fastest shifting hermaphrodite in CO

Startup and first test drive:

https://rcpt.yousendit.com/752652629/4a ... 16fed9cecc

I'm speechless.

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Had a:
1991 Eagle Summit ES Hatchback - 4g15 12v 5spd
1991 Dodge Colt -4g15 12v 4spd
Have a:
1978 Oldsmobile Cutlass - 468BBO TH350
Round 3:
1990 Dodge Colt-4G63T 5spd

why????

Probably because this is one of the most insane builds we've ever seen, and now it's finally on the road--really awesome. I can't wait to see vids of it in action.

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91 GSX - 511fwhp and 352 lb/ft 25psi 110 octane, 7.68 @ 95.9mph 1/8th 21psi 91 octane, 11.93 @ 112.9mph, 117.7mph best trap speed, 20psi 91 octane
98 Volvo S70 T5 - DD

http://www.facebook.com/captaintonus

^^Yep. This is an awe inspiring build. I would go to jamaica just to get a ride in this thing.

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Had a:
1991 Eagle Summit ES Hatchback - 4g15 12v 5spd
1991 Dodge Colt -4g15 12v 4spd
Have a:
1978 Oldsmobile Cutlass - 468BBO TH350
Round 3:
1990 Dodge Colt-4G63T 5spd

You're in a class all by yourself as far as fabrication goes. To build a car from the ground up is amazing. Could you even guess how many hours of labor you have in this thing?

Keep up the awesome work and keep us updated!

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93 Mitsubishi Expo LRV 1.8/manual
95 Eagle Summit DL Coupe 1.5/manual
01 Mitsubishi Mirage ES Sedan 1.8/manual

Pure Evil. Nice vid intro...

Is this where you will be unleashing that insanity's wrath? -
http://maps.google.com/maps?hl=en&clien ... maica&z=16

Complete w/ laaate braking and b@ll shriveling turn apexes along the lines of:
http://www.youtube.com/watch?v=ycgWVn1j8EQ !?!

More updates!,
#89

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#89