What will it run?

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mshred

mshred

The Green Manalishi
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Ive inputed all this info into desktop dyno and drag, but i know those programs can be overly optimistic.

heres the setup
1991 LA 360 shortblock bone stock rotating assembly with the pistons a mile down in the hole (factory dished)...
62cc RHS heads as prepped by Brian at IMM engines for a total compression of (hoping) 9:1-9.5:1..I did some calcs on summits site accounting for the 62cc heads, stock bore and stroke, pistons down .0705 down in the hole and a 5cc dish with the mopar thin 0.024-0.028 compressed thickness head gaskets gets me a compression of 9.5:1

Cam is a custom hydraulic roller from Brian at IMM to go along with the RHS heads
230/230 at .50 duraiton
576/576 lift
105LSA with 4-5 degrees advance ground in

Running the cam with Hughes 1.6 ratio rockers and shafts
RPM air gap intake with a 750HP
1-5/8 headers into a 3" exhaust with x-pipe and borla xr-1 race mufflers

2.66 first gear 4 speed with CF DF clutch, 4.10 dana, 3400lbs with me in it, caltracs and ranchos out back, calvert 90/10's, /6 t-bars and RMS UCA's up front
28x12.5 ET street tire

What do you guys think it will run? I will be pleasantly surprised and quite extatic to say the least if it actually runs what the program predicts, which is:

peak hp: 397 at 5500rpm
peak tq: 407 at 4500rpm
11.82 at 114.8 in the 1/4 with a 1.78 60ft. launching at 4000 rpm and shifting at 6k...if this were to happen, id probably faint from disbeleif at just how simple this combo is

However, I am not even really concerned with these shift points since me and Brian discussed that this combo could see over 6000rpm, at most 6500 shifts..all shifts will be with the throttle matted through a v-gate shifter

I know what to expect from it, but im really hoping it will run better than what I think...So let em fly, what do you guys think?

And BTW Brian at IMM is a great guy to deal with! Will definitely be going back to him for any engine needs! Very nice, knowledgable and is very competitive with his prices!
 
Ok, you know basically what was in my stock bottom end magnum with RHS heads, the race weight was 3200, guestament FWHP was 340-350, I was running 3.73 gears & 27" tire, best 60ft. was 1.79. 12.5s @ 105

Your biggest setback (so to speak) is the stick, I would say at that weight & HP, If you practice on the launches & get decent at it you should see good ETs, I'm going to say very low 12s (like 12.teens) only because you'll need to be in the 1.6s to see 11s, thats going to be hard when you dump the clutch & it boggs momentarily, what will help is a 2 step, its good your going with ET streets instead of DRs.
 
Ain't that what drag strips are for?
 
JoeDust451 said:
Ok, you know basically what was in my stock bottom end magnum with RHS heads, the race weight was 3200, guestament FWHP was 340-350, I was running 3.73 gears & 27" tire, best 60ft. was 1.79. 12.5s @ 105

Your biggest setback (so to speak) is the stick, I would say at that weight & HP, If you practice on the launches & get decent at it you should see good ETs, I'm going to say very low 12s (like 12.teens) only because you'll need to be in the 1.6s to see 11s, thats going to be hard when you dump the clutch & it boggs momentarily, what will help is a 2 step, its good your going with ET streets instead of DRs.
Click to expand...

Hey Joe, if i can run a low 12 ill be extatic! Im hoping the caltracs will help me hook...you must have read my post wrong, I am using ET streets, not the drag radials. And I also have a two step hooked up as well, so between that an the v-gate, im hoping it will launch hard and i wont miss a gear...as you already know combo's like yours are my inspiration, and i really hope i can run similar to that

StrokerScamp said:
Ain't that what drag strips are for?
Click to expand...

yup...but the car is still being put together, and the tracks here arent opened yet...come on man, don't u know i live in igloo country? lol

805moparkid said:
seems like a big cam for such low compression...
Click to expand...

I actually think the cam is perfect for what i wanted. The lift will match well with the flow numbers of the heads, while the duration will really emphasize a strong midrange. The LSA will give me the nasty idle i love but will also help pump compression as far as I have read elsewhere. I don't have any doubts it will perform as intended, just trying to get an idea of what I can expect from a low compression combo like this
 
805moparkid said:
seems like a big cam for such low compression...
Click to expand...

Not if Brian helped with the combo (i'm sure he did), that guy knows his SBs quit well, i'm sure it'll be a screamer. & that cam is not that big.
 
mshred said:
Hey Joe, if i can run a low 12 ill be extatic! Im hoping the caltracs will help me hook...you must have read my post wrong, I am using ET streets, not the drag radials. And I also have a two step hooked up as well, so between that an the v-gate, im hoping it will launch hard and i wont miss a gear...as you already know combo's like yours are my inspiration, and i really hope i can run similar to that



yup...but the car is still being put together, and the tracks here arent opened yet...come on man, don't u know i live in igloo country? lol



I actually think the cam is perfect for what i wanted. The lift will match well with the flow numbers of the heads, while the duration will really emphasize a strong midrange. The LSA will give me the nasty idle i love but will also help pump compression as far as I have read elsewhere. I don't have any doubts it will perform as intended, just trying to get an idea of what I can expect from a low compression combo like this
Click to expand...

If your really want practice on your shifting throw a 150 shot at it :salute:
 
Don't be affraid to run a bit more air pressure , to help get a bit of spin out of the tire.

Is the trans modified at all?...Pro shifted or Face plated????.

Don't try to set the world on fire, just go out there and make a solid base line run and build on it!.
 
JoeDust451 said:
Not if Brian helped with the combo (i'm sure he did), that guy knows his SBs quit well, i'm sure it'll be a screamer. & that cam is not that big.
Click to expand...

yes, I agree! After talking with Brian I have total confidence in the whole combo, and im dying to get it out and test....just need some good weather here, and the car together too lol...not exactly work friendly in the non heated garage in winter

JoeDust451 said:
If your really want practice on your shifting throw a 150 shot at it :salute:
Click to expand...

I wanna do some baselines on the motor and get it tuned that way first. I got a couple of grudge races setup, which is where the spray is coming in...but, if i can get it running real good on the motor, i may even hold off on the bottle for now

416Todd said:
Don't be affraid to run a bit more air pressure , to help get a bit of spin out of the tire.

Is the trans modified at all?...Pro shifted or Face plated????.

Don't try to set the world on fire, just go out there and make a solid base line run and build on it!.
Click to expand...

Hey Todd, im going to start higher with the air pressure and work my way down. My plan is to get a couple revolutions outta the tire on launch and then go to help take some of the shock out since im not running an adjustable

The trans is not modified at all, but i figure at this power level and keeping the shifts at 6500rpms or under i should be fine. Im very excited to keep the throttle matted and shift with the vertical gate, gonna be a blast!:supz:
 
any other guesses? or is this combo way far fetched? lol
 
After thinking asbout this for a bit , i think the only thing holding you back is compresion. BUT if the cam is installed to build cylinder pressure you'll be "OK".

I'm hoping for low 12's after some tuning.

The "non" modified trans and clutch will hold you back...hate to say it.

But you need some driveline slip and a trans that WILL allow you to slam gear changes at higher rpm.

Prove me wrong!...I hope you do.
 
Yes, the compression is definitely what is holding me back, but im really hoping that with the smallish chamber on the heads, the thin head gaskets and the cam spec's i can hopefully raise it enough to perform well.

I know that the stock trans and the non adjustable pressure plate will never be as precise as an adjustable unit, but this is a low buck street combo. I think if i can find a sweet spot for it maybe i can be consistent. If it runs a low 12, I will be happy! lol
 
Dago Red said:
X 2

High 12's
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I don't get the whole big cam thing...the duration is not big at all, very mild actually. The lift isn't even high, its actually just right for the heads. The LSA is tight to nasty up the idle and build cylinder pressure and compression (The LSA was chosen before I even made my desired idle characteristics known)

crackedback said:
Read this if you want some ideas on potential. Granted this one has 10.8:1, but I think the 400hp number bounced around is a bit light on power estimates.

http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Board=Racer&Number=3508495

That cam might have big lift numbers, but, it's not big on duration.

It'll make enough power to run high 11's if tuned up properly.
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amen to the cam specs...I have seen that thread before and it is quite interesting how much power that motor made, but thats a 408 stroker motor. Mine is a stock stroke 360.

Do you still think high 11's are possible with my combo with proper tuning? I know what to expect, but i have this lucky feeling that this combo will run better than everyone is telling me only for the fact that some others with very mild and similar combos are running quite well...if it doesnt, atleast i didnt get my hopes up, but if it does, man i will be happy:thumleft:
 
Watch what it MPH's. If it's in the 111+ range it's got high 11's in it.

There's a 360 engine in Brian's shop with a similar cam, 10.75:1 and street ported eddies and the guess is it should push the car it's going in to low 11's, maybe high 10's if it's light enough. Time will tell.

ET is suspension/chassis
MPH is HP
 
crackedback said:
Watch what it MPH's. If it's in the 111+ range it's got high 11's in it.

There's a 360 engine in Brian's shop with a similar cam, 10.75:1 and street ported eddies and the guess is it should push the car it's going in to low 11's, maybe high 10's if it's light enough. Time will tell.

ET is suspension/chassis
MPH is HP
Click to expand...

Yes, im definitely going to be watching those timeslips....damn im getting anxious to see what this thing will do

As far as the hook goes, I learned all of that the hard way last year. Ive done everything I can to my suspension front and back other than going to very expensive double adjustable shocks or a different rear suspension setup i.e. ladder bar, 4 link, etc.

Some weight reduction would help, but being a full interior street car with a stereo and maintaining my basic level of comfort, it seems hard to find any ways left to shed some weight..im going to try though this year
 
It's a pretty tight engine as far as the 9.5 compression vs the cam specs.
You could have even used more duration and been fine.

I like the 4000 grand converter for the engine.


The car will be a 60 foot monster and that's where your et will come from.
11.90 to 12.20 is my guess at 108 to 111 mph.

You hardly ever see any body run a tight lsa.
That cam will out perform many bigger cams just because of the lsa being right for the engine and combination.
 
T67POWER said:
It's a pretty tight engine as far as the 9.5 compression vs the cam specs.
You could have even used more duration and been fine.

I like the 4000 grand converter for the engine.


The car will be a 60 foot monster and that's where your et will come from.
11.90 to 12.20 is my guess at 108 to 111 mph.

You hardly ever see any body run a tight lsa.
That cam will out perform many bigger cams just because of the lsa being right for the engine and combination.
Click to expand...

another exciting prediction!:razz: it isnt a converter car though, gonna be shifting my own gears with the man pedal!:thumbrig:
 
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