Welcome to Modern Mopar Forum

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more! This message will be removed once you have signed in.


Whippled 405 Jeep Srt8

143 posts in this topic

I’ve gotten a lot of help from this forum so I thought I’d share my current project.  I’m not near as experienced or as smart as the big dogs on this forum but I do what I can.  My dad and I are currently working on a little father son project which includes swapping out the stock shortblock for a Dave Weber 405.


This project started over a year ago.  Dozens of phone calls to several vendors and lots and lots of research led me to Dave Weber at Modern Muscle Performance Group.  I’ve worked with and bought several things from most all of the vendors in the Hemi community and Dave was the best fit for me.  Our goal is a street oriented, driver friendly, powerful machine that can launch hard on the street.  We are not interested in any track records.  After a lot of discussions, Dave, my dad, and I decided on a 6.1L based stroker with Thitek heads.  The actual pistons and pins Dave had in mind didn’t exist at this time other than in his head.  We had nothing but time and were in no hurry for the engine so we gave him the go ahead to start things rolling.  He worked with Mahle over the next couple months and the pistons came to fruition.  Dave also worked with ATI to get me a 17% overdrive damper that was lighter weight than the norm. 


It was apparent from the beginning that the limiting factor of the engine would be the Magnuson sitting on top.  Initially, the plan was to build a bottom end that could support the Maggie maxed out but as things escalated, as things often do, the Maggie became the weak link.  Whipple had a new 2.9L twin screw out that would be a better fit but they didn’t have one for the WK1 engine configuration.  Dave talked us into a Whipple and challenged us to make it work.  So that’s what we did.  We pulled the Maggie off and sold it.  Put the Whipple on and redid the fuel system completely for the future goals.


Dave finished up the engine and we received it late in June.  We’ve been sitting on the engine waiting for the winter when we can take the Jeep down for a few months.  We’ve used that time to fine tune the Jeep and get it as ready as possible for the new power plant.  I’ve had a lot of fun driving it and the weather has been unseasonably awesome for the last month so I’ve been taking advantage of that and been enjoying the Jeep.  I expect to take a couple months to tear down the engine and build it back up.  I want to redo some custom brackets I’ve made and that will be time consuming but so much easier with the engine out of the way.  Same with the wiring.  The stock wiring harness is going on 10 years old and needs a lot of tlc.


6.1L based iron block 405 stroker.


The build up.










The heads. 

Thitek 100-2125

2.125” hollow stem intake

1.65” exhaust









The delivery.

Had it delivered for a dock pickup.  Forklift into the back of the truck and easy ride home.








New engine hoists first pick.



Bought some castors for the cradle and now it rolls around like on roller skates.



Waiting for the right time.



The Jeep.



The Whipple.


Stockpiling parts for the project.



The Kooks have been waiting a long time to go on.



Since we’ve had the engine sitting around the garage for a few months we decided to detail it a little.  I didn’t like the casting flash on the timing cover and I also wanted to paint the water pump in order to keep it a little cleaner.  So we smoothed some things out.






























I found an oil filter adapter on ebay and got it for $15 shipped.  I bought some new seal and bolts and cleaned it up and painted it as well.






Here are some of the things I’ve been collecting and working on over the last few months.


New sensors and hardware.  With my Jeep being about 10 years old and 75k+ miles on the thing, I decided to just go ahead and get new sensors.  If any fail right away, I always have my stock ones as backups.




I have lots and lots of parts waiting to go on this pig.




I’ve tried a few different tensioners and so far I’ve had luck with the Dayco.  I changed out the plastic pulley for a Procharger metal pulley with a lip that I got from Demon Performance, thanks to Nate.  This will be installed initially and see how it can handle things.  If this doesn’t work then I will upgrade to a GT500 with an adapter.  I ground off most of the casting and painted this as well. 










I have another Procharger metal pulley with a lip that will go in place of the stock idler but it is currently running on the Jeep right now.  That one will get transferred over.


Share this post

Link to post
Share on other sites

Nice Build!  You and your Dad must be wishing it was the winter months now.


All very nice parts.


So no track records, but you have Thiteks :)........  what ET are you looking to go for?


Linda :)

Share this post

Link to post
Share on other sites

Wow..... nice build thread. 


You and your father going to make some good memories with this build. Nice attention to the little details in this.


Keep the pix coming! We love build threads.


Looking forward to the end result.



Share this post

Link to post
Share on other sites

Thanks all. 


Looks great. Those pistons have a heavy dish, what ratio is she?


Those are Dave Weber’s 2618 pistons.  The dish isn’t as bad as it looks.  Hell, maybe it is, I don’t have a huge reference to go by.  I’ll be using a 0.060 5 layer head gasket which I think puts the cr real close to 10.0 to 1.


Nice Build!  You and your Dad must be wishing it was the winter months now.


All very nice parts.


So no track records, but you have Thiteks :)........  what ET are you looking to go for?


Linda :)


Winter should be a good time.  If I were to guess on an et… something that would probably get me kicked off the track due to no cage.


More about me;  Some of you know me, my name is Kevin.  I just turned 40 and my dad just started his semi-retirement a few months ago.  He now works from his home office.  We play with cars as a hobby.  Here are some of our current and past projects.


My 2005 AWD Ram

05Ram01.jpg 05Ram02.jpg



This is my dad’s 2003 Harley Davidson Edition F-150.


Harley engine



I sold this G37 to fund my project Jeep.  It was a fun little pocket rocket but needed another 150hp.




Our old fox body.  My dad had a Cartech turbo on this thing in 1989 before anyone even knew how to really modify the fuel injection stuff.  This car would blow the tire off from an 80 mph roll.




My dad's 2007 300C SRT8.  We did a heads and cam swap, ported tb and intake, magnaflow midpipe and corsa exhaust, and 3.55 in a getrag.  With the 305 drag radials, it’s awesome.  We love boost but damn, got to love naturally aspirated instant power.  It’s so smooth and driver friendly but an animal when asked to be.




Here’s a project that has since been sold.  Pro Street Trans Am GTA (no engine in this pic).


Remember back in the mid 90’s when the Chevy 502 crate engine just came out?  My dad wanted to see if he could stuff one into an f-body.



Dad's funny car running 8's back in the early 80's.  I was born and raised at the drag strip.  Seriously, I’m part deaf in one ear since I was a kid.



Share this post

Link to post
Share on other sites

 ^^^^^^^^ Yup Exactly, Never do you buy Thiteks if you don't want to go Fast !

And getting kicked off the Track with no cage, is a cool goal to go for ;)



Linda :)

Share this post

Link to post
Share on other sites

I took the Jeep to a shop to evacuate the Freon for me.  Then I drove it straight to my dad's garage and we tore into her.  Put it on the lift and drained the fuel lines and drained the coolant from the intercooler system so we could pull the supercharger and tub.  We also pulled the midpipe out and unbolted the torque convertor.




If the Kooks go on as planned, this will be for sale soon. 




Before too long we had parts everywhere.  I've had a lot of these pieces off before but it was a first for several of them.




We've found part of the engine.  Problem is, there's a lot more left to find.




If for no other reason, this thing should run better just due to weight reduction.




Yes, we took off more than was necessary but this is our first engine swap in the Jeep and we tend to error on the conservative side.  For example, the headlights could probably stay on but they are one plug and two screws away from being off.  So much more room and they are out of harms way and I spent a lot of time building those things. 


Then I dug this thing out.



Share this post

Link to post
Share on other sites

Nice progress and that's a bad ass garage.  Your detail work is a page out of my book.  The timing cover and even the Dayco look night and day better.  Keep up the good work.

Share this post

Link to post
Share on other sites

Removed the transmission and t-case.  Not sure if this was absolutely necessary but we weren’t sure if we could get the dowel pins to separate between the engine and transmission and we really wanted to try to get the engine out with the heads still on if possible.  We also thought we would probably have to push the Jeep off the lift and over to the empty stale to use the engine hoist.




Decided that we would try to mock-up the engine hoist while on the lift.  We were under the impression that the only way to pull the engine out the top was with the heads off.  I asked several of the experts and they told me that the only way to pull the engine with the heads on was if you dropped the cradle.  We also figured we would have to move the Jeep off the lift to pull the engine but that wasn’t the case either.




Well before too long, the engine was hanging in the air and it got pulled out all in one piece with the heads still on. 






Look at the size of that hole!




More garage art!




I was hoping this project would take most of the winter but the whole thing is disassembled already.  Time for detail work and cleanup.

Share this post

Link to post
Share on other sites

New 405 next to the stock 370.




This is just a picture to compare the size of the intake ports between the stock heads and the Thiteks using a gasket for reference.






Setting up shop.



Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now