MY 350TPI SD built..imput?
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Car: 88 IROC
Engine: 305TPI
Transmission: T-5
Axle/Gears: 3.42
MY 350TPI SD built..imput?
Ok, I just picked up my freshly rebuilt sbc. Its a 30 over 350 4 bolt(aprox 355ci) I'm running 113 aluminum corvette heads(brand new). I'm runining a 10:1 compression ratio, 1.5 rockers, SLP runners, 52mm BBK throttle body. Stock lower/upper intake. I plan on porting the heads/intake/runners. 24lb injectors, adj fuel pressure regulator. with comp cam XE268H http://www.compcams.com/Company/CC/c...x?csid=86&sb=2 I have a guy that will dyno tune my car in the spring with a completely custom tune. Any thoughts on my setup here? I know the stock tpi dont work the best for massive power but i figured I'd try and save some cash and just port the snot out of the base. I want a stump puller.
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Car: 67 ******mobile
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Re: MY 350TPI SD built..imput?
You can port the stock base but youl have a LOT of time into it to get it to move some air, had over 20 hrs in my last one (did go a little overboard though).
Think you can make 300 with the stock valve head ported but to make real gains youll need large valves and a full port job period. Intake ports require a bunch.
Trying to find my last flow sheet from a stock valved ported 113....
Think you can make 300 with the stock valve head ported but to make real gains youll need large valves and a full port job period. Intake ports require a bunch.
Trying to find my last flow sheet from a stock valved ported 113....
Last edited by cuisinartvette; 01-22-2011 at 07:45 PM.
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Re: MY 350TPI SD built..imput?
Ok, I just picked up my freshly rebuilt sbc. Its a 30 over 350 4 bolt(aprox 355ci) I'm running 113 aluminum corvette heads(brand new). I'm runining a 10:1 compression ratio, 1.5 rockers, SLP runners, 52mm BBK throttle body. Stock lower/upper intake. I plan on porting the heads/intake/runners. 24lb injectors, adj fuel pressure regulator. with comp cam XE268H http://www.compcams.com/Company/CC/c...x?csid=86&sb=2 I have a guy that will dyno tune my car in the spring with a completely custom tune. Any thoughts on my setup here? I know the stock tpi dont work the best for massive power but i figured I'd try and save some cash and just port the snot out of the base. I want a stump puller.
The 113s are good to about 350-375HP.
24lb injectors are a little light for my taste, I'd like to see you in 26 or 30
Careful with the adj, FP reg. The cheapo caps like Accel, BBK, etc... offer have two problems. 1. the vacuum nipple tends to fall off, and 2. the screws don't hold. Typical problems. We sell a modified GM regulator for $150. Much better reliability.
You're not saving much in porting the base, I think the Accel base is $400 new, you can probably get an EBAY one used cheaper. What's your time worth and what results are you going to get? Opening it up to a flow number is one thing, but air quality delivery is important, don't get bogged down in flow numbers.
Other than that, sounds like a solid combination.
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Car: 88 IROC
Engine: 305TPI
Transmission: T-5
Axle/Gears: 3.42
Re: MY 350TPI SD built..imput?
I have everything except the injectors and the adjustable fuel regulator, I have a friend that offered to help porting the intake(engine builder) and I'm a college student so I'm trying to do a semi-budget build. I have about 1600 into my current setup. As for power I'd like to think I should be in the 350-400hp range here, but when it comes to cam to engine combos I'm not really sure.
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Car: 88 IROC
Engine: 305TPI
Transmission: T-5
Axle/Gears: 3.42
Re: MY 350TPI SD built..imput?
Humm.... this is all food for thought. From what i've read you can take a stock base and port it to flow just as much or maybe alittle more then and aftermarket. I don't mind putting time into it, I don't have the lux. of throwing money at it. If I can make the stock flow the same or better I personally would rather do that. Am I in the wrong here?
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Re: MY 350TPI SD built..imput?
no you can do that, but a ported aftermarket will flow even more and when combined with a matching head/cam setup, it will make more power But if you are happy with 300whp, a ported stock base may just do all that on mild cleaned up 113 heads...and i mean casting smoothed out in the head ports, new valve springs and a good valve job..no real port work but a few hundred bucks spent on the pocket/bowls will help alot.
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Car: 88 IROC
Engine: 305TPI
Transmission: T-5
Axle/Gears: 3.42
Re: MY 350TPI SD built..imput?
I called one place and they said 600 to port the heads and the Intake together. How far of a port job I'm not sure. The internal stuff I don't really know too much on. How much porting can be obtained on an aftermarket base...Worth messing with? I already have a different set of springs that are supposed to increase the overall lift capabilities of the heads to I believe .510. I was have read that you don't want to exceed .470 lift on stock springs. I don't have the box in front of me. Would it be wise to opt for the 1.6 rockers instead of 1.5. How much is that going to affect tuning?
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Re: MY 350TPI SD built..imput?
IF you get the heads ported, atleast get the valveguides cut down and put in a good double spring. that should handle .550" lift easily and those heads do like mid lower .500's lift.
If the heads arent ported alot, then I dont expect flow to exceed 230cfm and 260-270 is the most i've heard you get out of them with a larger valve. IF you flowed 260-270, an aftermarket based heavily ported is recommended... but if you flow only 220-240, then you dont really need a ported aftermarket base...just gasket matched.
If the heads arent ported alot, then I dont expect flow to exceed 230cfm and 260-270 is the most i've heard you get out of them with a larger valve. IF you flowed 260-270, an aftermarket based heavily ported is recommended... but if you flow only 220-240, then you dont really need a ported aftermarket base...just gasket matched.
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