E58 400 plus HP Dart sport build

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Again thanks for the advice all jumped and explained it really helped a lot. I would not have done this in just over a year with FABO great group of folks appreciate it. Been following builds here since 2010.
 
They are true 1.6 ratio roller rockers red and blue in picture. Stock are actually below 1.5. checking cam spec valve lift I'm now 526 intake and 540 exhaust. This cam is @107 rather than 110 so has overlap. For sure need to go to 3.73 rear gear. I fixed the tachometer tonight pulled out of loom and wrapped in foil tape. Also put that inside a 1/4 vacuum hose ran through one of the plugs it used for firewall insulation. Then checked no RFI issues tach is steady at idle. Speedometer same issue fixed tomorrow. Ran it up first gear 4500 holy cow and into 2nd before I chickened out. She is ready to go for sure. Just needs miles like you said rumble fish. Temps still right at 190 or lower very pleased with AC I needed it down low Oklahoma is HOT.

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Here’s the thing, there are several companies that offer a 1.6 roller rocker but they do not all exact lift the valve a true 1.6 mathematically. Or in actuality. Is the differences in the contact point of the roller tip the push rod contact point and the frog buckram point and the differences between them, additionally, pushrod length also has a play in this. Double check to see what your actual lift is.
 
Here’s the thing, there are several companies that offer a 1.6 roller rocker but they do not all exact lift the valve a true 1.6 mathematically. Or in actuality. Is the differences in the contact point of the roller tip the push rod contact point and the frog buckram point and the differences between them, additionally, pushrod length also has a play in this. Double check to see what your actual lift is.
According to build sheet and what I and builder did it is as specified a 1.6 ratio. The stock push rods were short so they were changed out and measured for correct length and what we wanted to accomplish. Would not have used them anyway as pretty old as they were old tired looking rocker assembly.
 
According to build sheet and what I and builder did it is as specified a 1.6 ratio.
What is the cam card saying for it’s lift?
The stock push rods were short so they were changed out and measured for correct length and what we wanted to accomplish.
Of course, there’s no other way. ;)
Would not have used them anyway as pretty old as they were old tired looking rocker assembly.
As in the old/OE rockers?


Not breaking balls or anything of the like, but…..
Your diction isn’t very conducive for easy reading.
 
Update on progress and let's get a why in there. Why did he build this car and this engine this way. Well what he thought to be true what he thought he knew hahaha.
So what did we learn. Be patient and not every you read from manufacturer is remotely correct mwhahahahaha. Example 13 inches of vacuum on a high lift cam. Ummm no lmao try like 7.....at 1000 rpm and out of lope land .

Not every thing is GD power valve say power valve I will hunt you down lol for the love of gawd if you comment at least make your gibberish better than mine. As said before I'm not great at explaining as Im usually pissed by the time I explain where I'm at. But yes I'm having a lot of fun.

What would I do differently. Well less cam I was talked into this. I would do less cam for more for more friendly tuning. I will be going to manual brakes or a vacuum pump. Less CFM carburator would follow would not need for the cam. Stroker kit to make up for cam as would have cost less. Less cam with my combo and more compression would have been same HP or close to it.

Buying parts then buying other parts to replace what I didn't like after the fact. Nothing is cheap do your research and reviews.

Anything stock under the hood that had hoses and uses vacuum if you change alot go radical ditch it you will be sorry if you don't. Vacuum secondary waste of time on lopey cam and power brakes. Not saying you can't is it worth the effort lol.

So now your thinking what's his plan power brakes can stay there usable not great. Vacuum secondary is gone plate in it's place. Changing to progression ignition eventually.

So all that's said is Vince enjoying the drive well second gear drop around 6200 is amazing on a 2.94 gear. And third right after with a 727 is a lot of fun. Rumblefish360 is right a high compression/pressure motor is stupid addictive (even on the low side! I know I know I could have done things differently) Plan to get heads ported these can flow close to 300 cfm. Change transmission to a ZF 8hp70.

What's it like to drive it's a GD blast and I can straight up frighten friends and chase modern cars off. I'm guessing good numbers qtr hooks up real well gears will maybe make that harder to hook for now leaving it as is good match for trans change. I can't deal with 3000 at 70 plus mph hell no drives me nuts. Not to loud just wear and tear and gas mileage. Gas mileage yeah it has none. It does get to zero to 60 in a low 5 average few times was better but I was really in it .... Qtr no idea no track yet not really interested it's quick will get better with transmission.

Now call me nuts this is what my car did what I observed. Is it a good build with a XE268 cam this build would be great for a beginner. The cam I chose is great for what I wanted but it is not forgiving. Lots of extra work should have stuck to mild plan.

Last thing stay away from dumbasses.com they are crazy stupid.....they tell lies!
 
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First oil change went well torn open oil filter nothing found. Observation Pro-form restamped Mopar emblem valve covers are not Fing tall. If you buy them both vent holes using a 1.6 roller rocker will smack and you will have to take off then trim them cut your finger with die grinder. ***** and then clean them up and use another new set of valve cover gaskets and chew *** on Summit. Thought you should know ..grin!
 
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how much initial timing do you have on the engine?

I know you have a thumpr cam is it the small, mid or large one. If someone told you you would get 13in of vacuum with the mid or large one, yeah not gonna happen at a typical idle level. The large one is 240+ at .050, not "idle" or vacuum friendly.

Have fun with it. Good to read it is broken in and running strong.
 
how much initial timing do you have on the engine?

I know you have a thumpr cam is it the small, mid or large one. If someone told you you would get 13in of vacuum with the mid or large one, yeah not gonna happen at a typical idle level. The large one is 240+ at .050, not "idle" or vacuum friendly.

Have fun with it. Good to read it is broken in and running strong.
Large thumper cam and things have been changed were going to manual choke that's solved and the why. Getting rid of the vacuum advance on the distributor got a plate to install. It's driving great it really does not need a choke but since it's there manual if I need it just in case cable will be there. I changed the power valve 3.5 rear jets to 84. A/F sensor reads right around 11 to 11.5 idle but will adjust the idle metering screws out a smidge now. Driving A/F sensor is showing 11.5 to 13.5 it's a good average of 12.5. Power valve was 6.5 not bad but the 3.5 is a huge success. Matches the vacuum now of cam. Timing I'm at 18 degrees and total timing at 35. It's very snappy now and driving great best I have tuned it since I got her up and running. We're I to purchase carburetor again I would have gone non choke 750/850. Distributor would have had no vacuum advance from the start. Lessons learned and I can argue why you don't need those things on a hopped up strip street car driven on cruise in and for fun.
 
Appreciate this thread so much. You're at the finish line and i'm in your draft. Sucks when a machine shop takes their merry lovin time so I felt that when you got your block back. I just got mine after 11weeks of waiting for overbore, crank R&R and cam bearings done, and still have to build the bottom end. Expensive hobby but can't wait to fire up and get some of the same reward!

Also, what sold you on going to a ZF 8hp70 transmission next? curious as my 727 is a big question mark for me still.
 
I am enjoying the car now. Couple things I would do differently so here we go.

190CC heads
Roller cam conversion more money but maybe someday

Phased the cam forward and not at zero for driveability on street when installed the lope at 1100 rpm in overdrive and 40 will get you nutty

Started out with a Pertronix distributor ignitor 3 in the first place

Had my 850 Holley tuned by an expert prior. 5 emulsion circuits now and not 3 lesson learned on why and power valve matched better. Sharpton racing NE Oklahoma got that dialed in.
CAM
Maybe I could have gone with a 110 phased cam instead of the 107 little lopey but long as your 1500 rpm crusing or better it's fine. The ZF 8 speed sport or track mode or manual shift it's fine only economy mode in town lol will drive you bonkers. Highway at 81 mph at 2100 non issue and 20 plus smiles per gallon. Amazing highway and to fast for my own good.

Forged pistons - here is why boost not a safe or good idea on KBs do I need it no lol

Stroker maybe later debatable it has so much torque already I have broken a leaf and two shocks. Prior to full frame connectors is when I broke things. Now if I get to much grip it will axle hop done this twice and it's gawd awful. 8.25 rear so far no complaints little to narrow messes with my tire and wheel choice has to go but 2.94 gears are perfect with the ZF 8HP70. I know the torque is high as the controller can read it directly from output shaft 8hp70 trans stock is rated at 550 foot lb

Now let's talk stall and launch, does my car have lag will a lesser car and cam say 268 energy cam catch me? No not a chance in hell. If I dont hook and toast them yes any car has a chance.

This car off the line with a trans brake built into ZF it's amazing. The 3 speed was fast 727 no doubt but I gained at least two seconds not kidding in a quarter mile easily with the ZF. You can literally floor it from a stop to 100 MPH and it may wiggle a little here and there. Shifts come in at 6300 rpm with rev limiter set at 6400 the car is incredibly quick.

I credit the launch to frame rails and the tuning done in shift tables from Ma Mopar and Russel Drake at Sound German Automotive. These mid to high range cams are something else and for a non stroked engine she will rev comfortably to 7k no valve float. No reason to as cam is 1500 to 6400 and set my redline rev limiter by that guideline.

Comp claims a 2800 stall is needed and that is what a 2020 6.4 liter ZF transmission scatpack car is equipped with I'm told. Its still a bit lopey at stop light but not like 2400 to 2600 stock 727 converter. It's not rocking and rolling idling by any means in gear. 1000 rpm idle is very happy.

I'm not 100 percent sure on HP but all the guys around here in my area and builders think I over achieved on the HP goal. More around 450 or so they seem to think. I may dyno in Tulsa as I am curious same time I dont want them jacking up my car in process. The build I followed was a 420 HP build. However I bumped compression from stock to 11 to 1 by testing it. I also did a much bigger cam and a 1.6 roller rocker assembly along with much higher CFM to feed it.

Picture of the ZF 8HP70 8 speed transmission and new exhaust in now.

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Appreciate this thread so much. You're at the finish line and i'm in your draft. Sucks when a machine shop takes their merry lovin time so I felt that when you got your block back. I just got mine after 11weeks of waiting for overbore, crank R&R and cam bearings done, and still have to build the bottom end. Expensive hobby but can't wait to fire up and get some of the same reward!

Also, what sold you on going to a ZF 8hp70 transmission next? curious as my 727 is a big question mark for me still.
Wrote a big book below with comments on the ZF 8HP70 below. Launcher launches hook ups all of the above in the why. Sport mode/track mode and highway economy driving mileage wow on a built motor all true! Oh yeah manual mode hahaha on built engine in light A body. Lots of fun donuts and track the car check and check all day. The car is amazing I would never touch a 3 speed 904 or 727. ZF is plentiful reliable takes big power. Is there work to be done yes see my transmission thread it's still well worth the work as the reward is amazing.

My transmission cost me below
1000 26000 mile 8hp70 2020 Scatpack 6.4 car

400 adapter

1000 controller

600 8hp shifter used at junk yard 125 I wanted new OEM. I'm done being cheap do it right I say now.

400 driveshaft

100 transcooler remote

200 pfte gas 6an and 8an transmission line

Is it expensive yes but build a 727 right or buy it built with a warranty. Then add a gear vendor. Your around 5000 to 6000 dollars. I think I got ya beat even if you paid 1000 for fab work I still got ya for a cheaper better solution long term. Leat that's my opinion. But if you like your car stock that's great and I understand that or like the old 3 speed go for it.

The fabrication work was me and notebook paper and a square and ruler and measuring tape Ya know that's hard to say I guess I'm handy but I was told I did a really nice job and that I did it well. If I were to do it a second time would be even nicer I had no kit this is my kit.
 
that 8hp70 transmission is the best choice , wish I had enough time left to put one in my car ,It can't be beat for mpg or 1/4 mile times
 
See engine labs dyno build 360, I do plan to do some head work and I'm bumping compression up as well 10.2 to 1 should be right on the edge of 400 with better compression which they left bottom end stock pistons. Modifying And Testing A Dodge 360-Cube LA Small-Block On The Dyno
I have no dog in this hunt. But I will mention the westech dyno seems to be a little on the happy side compared to others.

For instance a stock rebuilt high compression 340 with headers and the comp 268 cam supposedly made 400 hp as well.

That said what you are putting together sounds like a great low buck street combo no matter what the actual horse power level winds up at.
 
I have no dog in this hunt. But I will mention the westech dyno seems to be a little on the happy side compared to others.

For instance a stock rebuilt high compression 340 with headers and the comp 268 cam supposedly made 400 hp as well.

That said what you are putting together sounds like a great low buck street combo no matter what the actual horse power level winds up at.
400 hp is possible my 340 dynod at 450hp with a decent cam 573 lift 1.6 rockers and trick flow heads . Don't think it was a happy dyno
 

400 hp is possible my 340 dynod at 450hp with a decent cam 573 lift 1.6 rockers and trick flow heads . Don't think it was a happy dyno
Cool build. I like them all and appreciate the hard work we all put in to our rides.

If I were set on the combo the op is putting together making the 400hp I would at least take a look at the comp 275 cam with the mopar lobes.
 
108 mph is a 12.30 with good short times. Moves pretty good according to the MPH!
 
that 8hp70 transmission is the best choice , wish I had enough time left to put one in my car ,It can't be beat for mpg or 1/4 mile times
Agreed I know it's not stock but my car is resto mod.
400 hp is possible my 340 dynod at 450hp with a decent cam 573 lift 1.6 rockers and trick flow heads . Don't think it was a happy dyno

My cam is well past the 268 now with 1.6 roller rockers installed 541 Intake and 528 exhaust. I weigh less than Russel Drake's truck from Sound German Automotive and he runs an 11 same transmission and horsepower nearly the same I'm told and out weighs me close to 900 pounds. I expect an 11 goofing around on phone timers Im seeing numbers that indicate I should be there. I'm a little concerned about going to track.

SAFETY. I need to handle the brakes and get a vacuum system installed to pump up the booster. It's a little low they work ok but I need to be able to be able to lock the car up and takes a little to much effort. With the 8 speed this car is over 120 mph very quickly it tracks great now and such stopping is my big worry. I'm not dying first trip to track lol! I do t expect to lock them but I do expect lot more brakes than I got now. They are brand new and they work pretty good in town but way to soft that's the low vacuum at work.
 
108 mph is a 12.30 with good short times. Moves pretty good according to the MPH!
I was slow off the line smoked through 1st and almost lost it hitting 2nd , with a better driver it could do much better
 
Agreed I know it's not stock but my car is resto mod.


My cam is well past the 268 now with 1.6 roller rockers installed 541 Intake and 528 exhaust. I weigh less than Russel Drake's truck from Sound German Automotive and he runs an 11 same transmission and horsepower nearly the same I'm told and out weighs me close to 900 pounds. I expect an 11 goofing around on phone timers Im seeing numbers that indicate I should be there. I'm a little concerned about going to track.

SAFETY. I need to handle the brakes and get a vacuum system installed to pump up the booster. It's a little low they work ok but I need to be able to be able to lock the car up and takes a little to much effort. With the 8 speed this car is over 120 mph very quickly it tracks great now and such stopping is my big worry. I'm not dying first trip to track lol! I do t expect to lock them but I do expect lot more brakes than I got now. They are brand new and they work pretty good in town but way to soft that's the low vacuum at work.
with that 8 speed and 400+ hp you better have good brakes , and locking up the wheels at 120mph is not what you want . Brakes should be number 1 on your to do list
 
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