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Discussion Starter #1
Ok so heres what im planning

92 dodge daytona, fully stripped down, as light as possible (2300 lbs?)

5 speed

3.0 with full top end work, porting and polishing heads and intake, 52mm throttle body, accel 7+ spark/fuel kit (computer tunable) with 30lb (ish) injectors. no unneeded accecories, just water pump and altenator, underdrive pulley

t3/t4 hybrid
methanal water injection
racing fuel (110 octane)
75 horse shot of nitrous

Ok so my questions, can i run 30psi of boost with the water/meth injection and a large intercooler? Will the stock shortblock take it? any idea about horses here? im guessing close to 600 w/no2

I know very little about building a fuel injected motor, so can I get the top end,and turbo done (with low boost, 7-10 pounds) and put on large injectors and the motor run without changing the ecm?

the accel unit is very tunable, but can i get the motor running well enough to drive without changing the computer?

this will be strictly a racer, no daily service what so ever
any suggestions and help would be appreciated
thanks
 

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You should be able to hit 600 hp on 30psi without the no2... Less boost if you bore the block out some. What kind of RPM do you plan on running? Stock valves?
 

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well, ive found out rather quickly there is no aftermarket for the motors. so jy cams. even with the better mits. cams, probably a 6000 to 6500 limit.(valve float is not cool, lol) Is there a valvespring you would reccomend, like a set of comp cams duals?
 

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The bottom end of the 3.0 is very strong minus the pistons. You'll have to upgrade to forged otherwise you'll have 6 ashtrays on your hands. I think stock pistons are only good to 300ish hp :confused:
 

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You should be able to hit 600 hp on 30psi without the no2... Less boost if you bore the block out some. What kind of RPM do you plan on running? Stock valves?
Actually have have been learning over the last year or so that large overbores are good for maybe 500-600 hp but when you do a big bore and try to lay down 30+psi boost the heads flex (the dohc heads) and when you have a bigger bore, weaker parts of the cylinder head deck are exposed to combustion and you are more likely to push coolant.

The issue is NOT fixable with headstuds and Oringing the block doesnt actually fix the situation.

We have no idea when the sohc heads will start flexing. Hassler said he used to lift the heads but that just isnt true unless he was detonating like crazy (which he probably was running 20+psi with no intercooler). Head studs are proven to not help the 6g72 and the fastest 6g72's are now using stock headbolts except for 1 car and it still pushes coolant because its bore is too big for the heads @ 900hp.
 

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well, ive found out rather quickly there is no aftermarket for the motors. so jy cams. even with the better mits. cams, probably a 6000 to 6500 limit.(valve float is not cool, lol) Is there a valvespring you would reccomend, like a set of comp cams duals?
What do you mean by aftermarket? The things you cant find easily are turbo kits but technically every other performance part you could need is purchasable even if you have to go to Australia to get it (custom intake manifolds).

Pistons, valves, cams, whatever you need is out there. Just takes more work then typing in your credit card number.

I dont think you have to worry about valve float at 6500 rpms even with stock springs......especially on our wimpy stock cams.

I dont think anyone has come up with a good solution yet when it comes to actually sourcing a stronger spring. There have been some guesses but thats about it. I do think you can get those from australia too though but you would think there would be something locally available.
 

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Anyways with that light of a car you probably only need 350whp and NO nitrous to run a mid 11 second pass.

Robert hasslers 2700ish pound duster has run 12 flatt with a tiny 16g turbo and NO intercooler and ghetto fuel control and no timing control.
 

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im not 100% sure whether the SOHC 24v springs are the same size as the 12v (id think they are but i dont know) if they are, Tearstone.com has some F/I valve springs for $360 i think, granded you would have a full set of spares though
 

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aka time to split your springs with someone :p
Would be nice to know if any springs out there are an honest match.

Honestly those are way to expensive. My custom valves were 388 dollars and they are about 12% lighter then stock which is probably going to do more for your valvetrain then ANY valvespring, especially since lifter collapse is probably a bigger problem then float.
Im sure 7000 rpms would have no valve float problems on stock cams because they are just so lame.

Vale springs should cost $2-4 a piece. Aka no more then 50 bucks for 12.

custom valves will save you 300% or more weight compared to things like titanium retainers. Still would be nice to find some though. I would prefer to do all I can to lighten things before I tried to increase spring strength.
 

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Given that this is a drag only setup and the goal is a quick ET, have you considered ditching the 5-sp and going with a 3-sp AT? High stall torque converter would allow you to tune the engine for the higher RPM band...

What are the details of your head porting plans?

(not sure you need 600 hp to get into the 11-sec range...)
 

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Discussion Starter #11
the only things i have even ported are big block mopar heads and sbc's, so my plan is to make the ports as large as possible, and clean up the combustion chamber and mirror polish it. port the intake and gasket match the manifolds.
 

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NOOOOO!!!!! DO NOT do that!! You will kill the flow. Velocity is your friend.

Yes, you will not need 600hp to hit 11's. I think you'll have an issue getting to 2300#s though. 2500 is doable though. Being that weight you will only need around 400-450hp to hit 11's comfortably. These power levels should be attainable with about 20#'s of boost with a propperly sized turbo with no N2O.

I too would suggest using an A670 for your application. For drag only an auto is the way to go. Gearing should not be an issue and you'll be able to stay well within attainable rpm's.

What you want to do is very possible.
 

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Wouldn't it be easier to lighten up a P body than a Daytona?

As for fuel control, I think MegaSquirt is currently our best option. And our only real option, other than carefully creating some other way of adding fuel for the extra boost.
 

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the only things i have even ported are big block mopar heads and sbc's, so my plan is to make the ports as large as possible, and clean up the combustion chamber and mirror polish it. port the intake and gasket match the manifolds.
Did you mean "port" matching or "gasket" matching. Gasket matching only slows the air down.

You want to target about 250-300 feet/sec velocity on the intake port at peak valve lift. The intake port needs to be significantly reshaped for that to happen.

What lift cam do you plan on using? Plan on about 13% squish because of the lifters (common rule of thumb, not sure what the specific number is for the 3L).

Not sure a mirror polish of the chamber is need. I would just hit it with a cross-buff.
 

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Gasket matching only slows the air down.

You want to target about 250-300 feet/sec velocity on the intake port at peak valve lift. The intake port needs to be significantly reshaped for that to happen.

By reshaped do you mean the intake port needs to be reduced?
 

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If you do the reshaping right, no port cross-sectional area does not significantly change. But it does require epoxy...
 

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Discussion Starter #18
so can you use the stock computer with bigger injectors to get the motor running? I just found out the accel system isn't avaible to the general public. only accel approved engine management shops:(
 

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The concept is to use bigger injectors and turn the base fuel pressure way back. Then use a Rising Rate of Gain (RRG)/Fuel Management Unit(FMU) to boost fuel pressure when you are in boost. Another option is cold start injectors...

I used a combination of those on Daytonastein.
 
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