Ajax’s intake manifold

[yellowcar]

Yep, I understand that 4 into 1 doesn't HAVE to mean all top end but since you were moving from a tri-Y to a 4 into 1 I was extrapolating and making the leap.

I did the same sorts of things with my Yellow 510. Since I had been down the race motor for the street route before and knew it was no fun (Or maybe I should say only fun a small percentage of the time) to drive a car around that had zero bottom end and needed to be rev’d to 10k to make any power. I wanted a motor that made lots of torque so I built a L/Z 24 (as a side note this was ~ 1990 and my brother had just bought a brand new 240) and originally, When I built the motor I did everything I could to keep the velocities up; conservative cam, smaller carbs (38MM Dell’ortos) and a small tube, short header. While the motor made lots of torque as predicted after a while I realized that it would rather give up some of the torque for additional top end. So, I talked to Rebello and had them grind a big cam, moved to 45 OERs and built a bigger tube stepped 4 into one header for it. It was an immediate improvement and while the loss of torque was noticeable the top end more than made up for it and that was without even jetting it correctly. It was running waaay rich so I am sure I would have picked up a lot more power when it was tuned. But then I found the 69, stole the dash out of the yellow car and now, there it sits…

Anyway, the short version is I bet you will be happy with your planned mods…boy hard to shut me up once I get started

[Ajax]

Anyway, the short version is I bet you will be happy with your planned mods…boy hard to shut me up once I get started

No worries there

Quoted for awesomeness.I think my engine definitely has the potential to break 200 on pump gas. It will just have to wait until some money is available- going to fix drivetrain first.

[Bigvinnie]

vinnie you sound like you know what your talkin about pretty well with the velocity. i am wanting to go all motor also with time. its all in idea right now but got to have a plan to start getting the funds so what kind of compression can you run on pump 93 gas does it have to be non ethanol or regular gas? ethanol raises the octane by 1 or 2 points does it not? the only problem i really see with all motor is the intake manifold and throttle body. in my opinion i think the throttle body needs to be slightly bigger than the stock one 5 to 10mm and with port and polish and bigger valves check my forum out man. zerothread?id=483743

I don't want to ajck Ajax's thread so I will keep it short.

On 93 pump gas you won't want to go any higher than 10.5:1. That is if you keep the ecu stock and use 310cc injectors which would be needed to keep the A/Fr's consistent with that compression ratio.

As far as velocity is concerned with runners do not over kill runner diameter's stock runner diameter is 44m, there is no need to exceed past 45mm.

Your TB can be bored there is really no need to exceed 64mm, there are a couple principles behind this logic, not only because the TB itself becomes a weak structure after 64mm.

When raising the compression always take squish and quench factors into consideration. If you have a pentroof head you will want a piston dish that is concaved in shape. If you have a hemispherical head you will want a piston dish that is flat in shape. thi shas to do with the properties of flow and swirl in the chamber, and believe it or not 90% of people building a high compression KA get this wrong, and get low results in HP.

Sorry to thread jack.

[jrad240sx]

hey this also 90's250sx i have another account couldnt get that one logged in but i had my car dynoed on dyno dynamics and made some good numbers. I have 9:1 comp. ratio. bc stg 2 cams and valve springs. stock intake manifold with egr eliminated and a cheap but decent ebay header..... fresh rebuild with 10lbs flywheel and clutch with lightweight underdrive pulley. ill post when i can figure out how to get this picture on here....

what do you guys think? blue line is hp and dotted blue is torque. that is first run with stock maps and after an hour or less the red is what my last run was...solid red hp dotted red torque

[Chaotic_Warlord]

hey this also 90's250sx i have another account couldnt get that one logged in but i had my car dynoed on dyno dynamics and made some good numbers. I have 9:1 comp. ratio. bc stg 2 cams and valve springs. stock intake manifold with egr eliminated and a cheap but decent ebay header..... fresh rebuild with 10lbs flywheel and clutch with lightweight underdrive pulley. ill post when i can figure out how to get this picture on here....

what do you guys think? blue line is hp and dotted blue is torque. that is first run with stock maps and after an hour or less the red is what my last run was...solid red hp dotted red torque

Not to be an a**, but those are still at or below the stock from the factory numbers. If you had a baseline dyno from where you started before you did anything at all to the car then those number would be more impressive.

[jrad240sx]

yea really close to the amount it makes at the crank... a stock ka gets about 125 to the wheels almost a 30 hp increase is pretty good considering im going to turbo in the future and considering the comp ratio is low 9:1 i think those are pretty good numbers....and not to mention this had a sohc motor in it so kinda hard to see stock numbers but with the performance parts without nistune only 117 hp then with nistune you take full advantage of what you buy with a good tuner! they arent super impressive and arent suppose to be considering its setup for turbo in the future and i didnt do that much to it it just took me a long time cause its my first build by myself. And also alot of people get there cars tuned on dyno jet which give you higher numbers and his dyno actually showed me those numbers if it would have been a dyno jet and it was 175 to the wheels. they call the dyno dynamics the heartbreaker because they show more actual numbers rather than overrating them.