SRT_DSTRHOLC
Well-Known Member
but it says unported heads
360 to a 408 how much quicker
- Thread starter stroker408
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Locomotion
Well-Known Member
* 750 Holley or Quick Fuel - with choke tower and flap.
* 904 w/2.71 low gear
* 4.86 rear
* Sunoco Purple
* Cam has 270*+ duration @ .050"
* Low tension oil rings
* Everything blueprinted by an engine builder who knows what works best under the rules - valve job, honing stones, ring gaps, etc.
* Honed with torque/deck plate.
* Lightweight oil and rear end fluids.
* Converter that flashes to 5,000+, but I shift around 66-6700.
* Light wheels and tires.
I picked up with a TTI X-pipe and Dynomax Ultraflos after some jet changes, found that a dual plane intake had more torque and actually flashed the converter higher by a bit, but a single plane was faster and run Hoosier 9" lightweight radials. Despite being "touchy" on marginal tracks, they are faster than bias ply tires and I have my suspension hooking well enough at IHRA event prepped tracks to be consistent. One way to look at it is that, despite not making a "lot" of HP (running a best of 115 so far), I am using the available HP and torque "efficiently" to run a best of 11.31.
These are just a few things that help to go fast and I'm always tinkering. It's a never ending learning process. My engine builder has his way of doing valve jobs, honing, etc. It's not just "parts". It's figuring out how to tune them and pick them to work together. It's not just what you put together, it's how you put it together. But this works for "MY" combo. Plugging in some items into another combo may help, or may hurt!
But, as mentioned, there are similar cars that are even faster! They have more time, money, dynos, etc. I started out running low 12's in 1999. So it's taken me 10 years of testing, tuning & refining this combo for a gain of less than a second under the rules so far. And I still have more to learn.
* 904 w/2.71 low gear
* 4.86 rear
* Sunoco Purple
* Cam has 270*+ duration @ .050"
* Low tension oil rings
* Everything blueprinted by an engine builder who knows what works best under the rules - valve job, honing stones, ring gaps, etc.
* Honed with torque/deck plate.
* Lightweight oil and rear end fluids.
* Converter that flashes to 5,000+, but I shift around 66-6700.
* Light wheels and tires.
I picked up with a TTI X-pipe and Dynomax Ultraflos after some jet changes, found that a dual plane intake had more torque and actually flashed the converter higher by a bit, but a single plane was faster and run Hoosier 9" lightweight radials. Despite being "touchy" on marginal tracks, they are faster than bias ply tires and I have my suspension hooking well enough at IHRA event prepped tracks to be consistent. One way to look at it is that, despite not making a "lot" of HP (running a best of 115 so far), I am using the available HP and torque "efficiently" to run a best of 11.31.
These are just a few things that help to go fast and I'm always tinkering. It's a never ending learning process. My engine builder has his way of doing valve jobs, honing, etc. It's not just "parts". It's figuring out how to tune them and pick them to work together. It's not just what you put together, it's how you put it together. But this works for "MY" combo. Plugging in some items into another combo may help, or may hurt!
But, as mentioned, there are similar cars that are even faster! They have more time, money, dynos, etc. I started out running low 12's in 1999. So it's taken me 10 years of testing, tuning & refining this combo for a gain of less than a second under the rules so far. And I still have more to learn.
sumbitmopar
Well-Known Member
I think it's going to depend on the carb tune and the traction. If the carb is tune real good (remember, you're feeding alot more cubes now so your probably gonna have to change something)and the car hooks up real well ( you should have a bunch more torque)you should pick up quite a bit. How much we'll have to wait and see! Good Luck and tune'r up!
Locomotion
Well-Known Member
Mine didn't cost near that, but his would run faster too!
SRT_DSTRHOLC
Well-Known Member
so i gues its all with tuneing and having the right parts.
I have magnum heads
a xe274 cam .524 lift with 1.6 rockers
kb107s 10.6 compression
4.10 gears
crosswind intake
bigs Stage 5 750 dble pumper
and i just want mid 12 to low 12 until i get the 360x head or edelbrocks
and what is on your car to lighten it up besides oils and wheels
I have magnum heads
a xe274 cam .524 lift with 1.6 rockers
kb107s 10.6 compression
4.10 gears
crosswind intake
bigs Stage 5 750 dble pumper
and i just want mid 12 to low 12 until i get the 360x head or edelbrocks
and what is on your car to lighten it up besides oils and wheels
Locomotion
Well-Known Member
Well, I actually had to ADD weight to get it to the class minimum weight in IHRA J/Crate Motor which is 3,530 lbs with driver. I usually race at between 3,540 and 3,580 lbs. I did remove some stuff allowed under the rules, like wiper motor, radio, heater core, blower motor, etc. which allowed me to put more weight in the trunk, like the battery & weight boxes, where it will do the most good, as well as frame connectors and 8 pt. roll bar.
Carb tuning with jets, pump cams & squirters is important. Jet for MPH and change squirters and pump cams for 60' & 330'.
Shop around for a good engine machine shop. They deserve a lot of credit. But the more attention to detail, the more expensive it is. Also, remember that some stuff is not "street friendly" for dual purpose cars, like low gears, loose converters, lots of cam duration, low tension rings, very lightweight wheels, etc. Needless to say, you have to consider the attention/rebuilds required with more radical combos. I try to swap out/freshen engines after a season or two. Some hardcore class racers do it much more often.
Carb tuning with jets, pump cams & squirters is important. Jet for MPH and change squirters and pump cams for 60' & 330'.
Shop around for a good engine machine shop. They deserve a lot of credit. But the more attention to detail, the more expensive it is. Also, remember that some stuff is not "street friendly" for dual purpose cars, like low gears, loose converters, lots of cam duration, low tension rings, very lightweight wheels, etc. Needless to say, you have to consider the attention/rebuilds required with more radical combos. I try to swap out/freshen engines after a season or two. Some hardcore class racers do it much more often.
stroked 340
Banned
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First off i Totally agree with Myron:thumbup::thumbup:..
73dart360 my 360 combo is:'77 360 block .30 over and decked
stock crank,Eagle rods
speedpro pistons/rings
Lunati "voodoo" .533/.552 hyd. cam
Edelbrock 65 c.c. heads slightly ported
Comp cam magnum rockers
Edelbrock air gap gasket matched
Quickfuel 850 carb w/1" wood spacer
Full msd ignition..
For my 416 substitute the 4" crank for the stock 360 and the 340 block was also line-honed,and runs Diamond pistons other then that same heads,rods,cam,carb,intake is used.. What really helps the 360 out is the 4.30 gears i run now,wheres as the 416 was running 11.0's with only 3.91's....:-D:-D
By the way i have a very GOOD machince shop doing my work,and an even better assembler putting them together for me,at least the shortblocks..
Sorry, I shouldn't have been sarcastic. But, you will always have the extra inches, no matter how much the 360 or 408 is scienced out.
Also, just for those that may not be aware, NHRA and IHRA Stock Eliminator have different rules than IHRA Crate Motor. "Stock" intakes and stock lift w/ any duration cams in Stock. "Stock" heads in Stockers, too. I was a NHRA Stock Elim racer for a while, I'm not familiar w/ Crate rules. Maybe Myron can fill us in some.
Locomotion
Well-Known Member
The main differences between "regular" Stock and crate motor Stock is that CM combos are allowed any unmodified, over-the-counter intake and a unmodified Holley or Quik Fuel carb. The carbs must come with a choke tower & plate. 750 for small blocks. 850 for big blocks. (Most don't come with carbs and the ones with manifolds tend to be flanged for a square bore carb.) Also, piston deck height is .035" including gasket across the board (to simplify things). Other than that, all of the IHRA accepted crate motors have manufacturer blueprint specs that need to be followed just like a "regular" Stocker. In my case, the 360/300hp Commando (factored to 320hp) cam spec is a hydraulic .474" lift., flat top pistons with 2 notches, OEM heads w/1.88" intake & 1.60" exhaust, + .015" stroke allowance, .070" max overbore, etc.
The original intent was to provide a less expensive way to get involved in class racing while using factory speced engines. No need to hunt for rare, expensive manifolds & carbs and heads are more modern and plentiful.
You can also build them from scratch, provided you use the appropriate parts, since some are no longer available as a whole. Most parts, like cam, rods, pistons, valves, etc. are swapped out for legal aftermarket parts anyway in any Stock class.
This was the main reason I got into class racing. I know nothing about Carter carbs and the Mopar combos have been so popular and refined over the years, resulting in some very fast cars, that I would have been a slow moving duck for any heads-up races. At least I knew how to tune a Holley from my bracket racing days.
73dart360
Well-Known Member
Those Are Some Nice Combos, I Like Seeing The Low Budget Race Cars, It Takes Alot Of Enginuity And Gives You Alot More Satisfaction When You Blow By A High Dollar Build.
SRT_DSTRHOLC
Well-Known Member
so your motor only makes 320? or you say it makes 320?
it was rated 320 from the factory...probably making alot more then that...
Locomotion
Well-Known Member
No, IHRA says that for "rating" purposes relative to other combos. The Commando 360 with small valves was originally factory rated at 300hp. After a couple of years of seeing how it ran against some other engines, IHRA decided it was under-rated and upped it a couple of times to the current 320. The result is having to weigh more or the vehicle/engine combo gets bumped up to a faster class. I use to be able to run in L/CM. Now it's I, J and K/CM.
Yes, I'm sure the engine makes a lot more HP. the weight/HP charts show something around 400+. I never had it on a dyno. But all the Stock class engines make more than their rating, especially after doing all the allowed modifications. It's actually just a reference number for classification. When Stock was first started, it was probably pretty close to the actual numbers. Now they allow much more duration, electric water pumps, low tension rings, etc. as well as other little "tricks" that can pass tech.
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