Johns cerbera rebuild and upgrade

[portzi]

been busy again today got the front suspensions all stripped out and the rack plus associated pipework, the shocks with suitable springs are now on the project maroon chim but the big news is the power plant has arrived all now uncrated checked and ready to start the implant into the now bare chassis,i also took delivery of my new engine crane so much better than the old ex raf one.

Hello John, your not ex Marine craft if you was serving in the mob??

Mark

[Brummmie]

While you have the box out, I would seriously consider getting rid of the plastic shifter fork pads.
Replace with metal ones.
I managed to rip the teeth off 3rd, but it took a few years!
I have a heat treated shot peened 3rd gear and shaft now.

What diff ratio/box did you go?
Did someone mention twin turbo!!??

Good effort.

[portzi]

Brummmie said:

While you have the box out, I would seriously consider getting rid of the plastic shifter fork pads.
Replace with metal ones.
I managed to rip the teeth off 3rd, but it took a few years!
I have a heat treated shot peened 3rd gear and shaft now.

What diff ratio/box did you go?
Did someone mention twin turbo!!??

Good effort.

So with a yank lump and twin turbo, what sort of cars will This be in the range of?

Mark

[NickOrangeTVR]

Brummmie said:

While you have the box out, I would seriously consider getting rid of the plastic shifter fork pads.
Replace with metal ones.
I managed to rip the teeth off 3rd, but it took a few years!
I have a heat treated shot peened 3rd gear and shaft now.

What diff ratio/box did you go?
Did someone mention twin turbo!!??

Good effort.

We decided on reflection to not go for the Turbo - the specialist who supplied the engine really 'knows his st' - we wanted to try and keep to AJP type power delivery and especially wanted to reduce the amount of Torque which is really hard to deliver in such a light car, so the Cam we had hand ground is going to give us 500BHP+ but probably 425-450lbs torque, it will be like the AJP a bit lumpy at low end but through mid+high end rev smoothly. (best made plans and all that....)

We decided given that were lightening the car considerably that 500BHP per ton was plenty for track use! And we also felt the extra money was better spent on suspension which is going to be heavily modified.

Engineer1949 can answer the detail of the ratio's we selected.

[robsco]

All this said, why not have just fitted a 4.7 AJP?

[Engineer1949]

I a word cost but other considerations are parts availablity long term plus should we want a 700 hp monster its easily doable not so with th ajp its not we dont like the ajp it is a grand engine just dosent suit this particular project.


John

[portzi]

Hello John, your not ex Marine craft if you was serving in the mob??

Mark

[Engineer1949]

fraid not just commercial marine big and small, but a small update just to let you know been side tracked by a chassis replacement to a griff but did get the chassis away for shot blasting ready for when the griff goes i can get stuck back in to getting the engine mountings done prior to its trip to emerald to go on the dyno.

john

[MPoxon]

Hi John, I read on your blog you are using a Motec ECU with advanced knock detection. Which Motec ECU are you planning on using?

[Engineer1949]

its been to long since i did anything worthwhile to the cerb but all the thinking planning etc. is done and the hard work begins firstly got the chassis and body set up ready for work in earnest tomorrow first job carry out a couple of little repairs to the chassis then install the engine and make manifolds etc. but some way to go yet couple of pics of her set up in the fab shop.


john

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

[Engineer1949]

to answer the last question we are now going to use emerald with the new traction control etc. etc.

john

[TimJM]

It's good to see this project back on here with an update. Keep the pics coming as you make progress.

Which seats are you using for this project, I can see them in the pic but not well enough to work out which ones they are?

[Engineer1949]

The seats are from intertrim several folk have them in there chims now ,they where in our chim but the colour didnt look good this car is going to be much more radical road legal race car basicaly so the seats will go in the cerb.


John

[Cerberaherts]

Very interesting thread! Please keep posting pics. How are you going to do your exhaust manifolds? Are you going to modify the chassis to get the engine nice and low and the exhausts clear? A couple of LS conversions I've seen have had the engine sitting pretty high, not ideal for suspension dynamics!

[Engineer1949]

good day today started by cutting out the rotten corner to the nearside front outrigger and replacing with new tube all looks well, then got the engine /box in place and lots of measuring both chassis and body eventually got it where i wanted sitting nice and low in the chassis and a bit further back than the original ,all works well with the planned two only seats being further back in the cab, i have fabricated the majority of the offside engine mounting all the final welding and gusseting will be done when the engine is out again but pleased with todays progress.

john

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

Untitled by brundallmotorsport, on Flickr

[Engineer1949]

just to answer cerberaherts question the engine is nice and low as low as i can get it without the flywheel being to far below the chassis, the engine is going to end up dry sumped leaving the ordinary sump on till its been to emerald on there engine dyno for mapping etc. going to run it in there as well, as to the manifolds i have got pure precision water jetting some manifold flange blanks i will tailor them to the heads then build my own tubular manifolds four into two into one both sides going to have a mid mounted box for best effect shall we say with the opportunity to fit the original cross body rear box for those tracks that need quiet


john

[Cerberaherts]

Engineer1949 said:

just to answer cerberaherts question the engine is nice and low as low as i can get it without the flywheel being to far below the chassis, the engine is going to end up dry sumped leaving the ordinary sump on till its been to emerald on there engine dyno for mapping etc. going to run it in there as well, as to the manifolds i have got pure precision water jetting some manifold flange blanks i will tailor them to the heads then build my own tubular manifolds four into two into one both sides going to have a mid mounted box for best effect shall we say with the opportunity to fit the original cross body rear box for those tracks that need quiet


john

Ah, dry sump. We'll worth the extra work and expense to get the engine dropped so low. Fabulous work, looking forward to seeing your manifolds. Will you be pulse-tuning them with a balance pipe? It's already shaping up to be a hell of a car..

Edited by Cerberaherts on Friday 9th January 20:54

[Engineer1949]

Martin short is letting me use his cad team to design the manifolds body mounting and suspension you may remember he is the man who built and drove the first successful cerbera gt race car back in the day so using his expertise to hopefully get it right first time,the car he built was a speed six they usd 27 engines in the first season but he also has lots of experience with the ls his moslers are powered buy the ls7.

John

[Brummmie]

The engine mounts look like they could be quite soft?
With the exhaust being so tight, as it has to be, and your alternator also very tight, be sure you have enough clearance.
I had to stiffen the pull side mount on mine as it was touching, with a poly bush.
I also used a Nissan micra alternator as it was loads smaller, and we are not needing such a current draw as a GM car anyway.

[Engineer1949]

hi brumme the mounts are metalastic originals i have a pair of uprated mounts from sc power on order with the heat shields they keep the blownc him under control but i am looking to put a torque reaction bar into the mix once the basic mounts are done.

john