supercharged 400ci chev

[TorqueFC]

we have recently aquired a fc sedan.

we want a further modified one than the one we now own. we were talking about going for a 400ci small block chev but have never attemped the conversions before. we know that in our fc that already has a 350 in it there is not much room whatsoever, which is the reason why im asking if recession of the firewall is needed.

also if we were to recess the firewall in what ways is it possible to move the engine furrther  towards the firewall

also is it possible to modify the subframes width on the inner side so theres more room between the block and subframe withought upsetting the mounting position of the guards and or grill.

with the fc we have with the 350 over heating has always been a worry, which is why were thinking of recessing the firewall, then moving the engine back so a larger capasity radiator can be fitted.

does anyone one this forum possibly have information, advice and/or pictures of a car with these modifications

cheers
torque

[FC-V8]

Torque
          A 400 is a small block & is externally the same size as a 350. I think the only difference is the 400 has an extra welsh plug each side.
Glenn

[GOA350]

Hey torque I will answer your questions later in more detail , but if you looked at my car you would realise that everything fits nicely without modifying the firewall much and I have an ally radiator and never have an overheating problem,
                               cheers GOA 350

[HARKO]

Did you find the power to weight ratio for victoria Tourque ?
Wow not in a million years could you legaly register that in NSW

[TorqueFC]

hey harko

no i havent found it yet, searched everywhere

there are a few victorian cars that ive noticed with 400ci chevs in em, and have been legaly registered.

GOA
our fc runs a 350 with a 5 core radiator but over heating is a little bit of a worry. in the next few months we will be purchasing a pair of pro topline heads from pavtek (750hp out of the box ). we were going to set them up on our fc until we rip the motor out, which will be in 2-3 years. our fc motor has had all bottom end work done, balanced steel crank etc. it will sit on aobut 180degrees cruising down the highway, but as soon as it slows down it begins to creep up. the block is an 010 block, 30 thou up.

ive done a few sketches, and to move the inner chassis rails one the subframe outwards, it would then need a different front end as the 4 front end mounting bolts would then be in different positions.

we wanted to make these modifications not only for more space but also so the motor can breathe a little better and also so it would look a little better.

rang around a few speed shops, most of them say 400 arent worth a pinch of s#^t, so may just go for another 350.

we can purchase a 350 010 block 10thou up for around $400, does this sound ok?, the block has been crack tested and recently bored out, and the place that has it is a flowcraft, which some of you may know.

also does anyone know how the firewall recession is done???. does the firewall get recessed just after the bonnet hinges, or does the hole lot get recessed and then different hinges get made.

Ken or possibly someone else on here may know, if the firewall is recessed, what type of pedal box and master could be setup???the car would be a 6sp manual box
(tremac)

thankz
torque

[Ed]

Hi Torque,

Having seen GOA's car it fits perfectly...

If u must recess a firewall here are some pointers...

dont recess any more than u need to. moving the firewall back will present you with a whole host of problems, you may as well then put a flat wall in.

it's a matter of simply cutting away the offending area, dropping the motor in and setting at the desired position and measuring the gap around the motor to your desired clearance.

here is a pic of a very bad recess job that was done on my wagon..

it reeks of amatuerism, and no I didnt do it.. i paid for this.. I ditn want to show these pics, but anyway..



I decided I could clean it up a bit.. so i got an EK roof and did some trimming and welding.



finally it cleaned up nicely to this...


The pedal box had to be modified on the firewall plate to clear the recess but essentially it is all stock.
The recess provides loads of room and additional clearance for the engine pipes.

Do NOT move your subframe arms for clearance, besides compromising the original design, it would reduce the structural integrity somewhat.

What some more spectacular conversions have are complete subframes from a more suitable car complete with front end grafted into place… A BIG BIG job but nevertheless possible.

Harko has just described his methods recently.

On overheating…
Has your fan got a shroud?
Is your radiator support directing air thru the radiator or does it allow some bypass flow?
My radiator is too small and after seeing GOA’s set up may get an ally one made up.

Hope this helps

Cheers

Ed

[TorqueFC]

thankz for that

i like the look of your firewall, is there any chance that you could post a pic of the firewall with the motor in it?

also how did you move your engine back, did you move the engine mounts???

on our fc everything is stock except for the top panel that would normally sit over the radiator is cut back. it does not have an engine fan as there is no room at all, but it has 2 thermos.

also there is only about 5mm gap between the water pump pully and the radiator and about the same between the harmonic balancer and bottom tank of the radiator.

cheers
torque

[FC-V8]

Torque
            If you are going to run a small block chev you don't need to modify the firewall. I have installed one in my wagon with pleny of room to run a fan & 4 core radiator with no mods to the firewall. Has your dads got a short or long nose water pump ?
Glenn

[TorqueFC]

short nose water pump

but we want to recess the firewall as the motor that wil go in will put out 600+hp so it will be in need of a larger capacity radiator

cheers
torque

[GOA350]

Hi torque,
              all i can say is i think youre heading up the wrong path. With Eds car the reason he has recessed his firewall so far is because he is running a 308 which has a wider V configuration than a Chev V8. In my opinion you should leave the firewall alone and concentrate on getting the radiator as far forward as possible. All I did was lower the front subby rail about 10 mm and widened the radiator opening out to the outer subby rails without sectioning anything then had a custom alluminium radiator made to suit by Race Radiators in Dandenong for about $700. Well worth the money considering how much I had already spent on my motor. I have a short nose water pump and have about 25mm between the fan and radiator. I also run an engine fan and a 16" thermo fan and my engine dosent get over 190 in traffic on a hot day. My engine is also 30 thou up with Pro Topline heads and whoever told you they flow 700 hp was playing with himself and you. The most they will flow is about 540 hp without having them ported.And on this they will only make these figures if you have the conbination right , eg; big cam , strong bottom end, carby manifold ect. In my experience make a detailed plan and stick to it , dont listen to your mates telling you  you need to do this and get that, make a plan , write it down and stick to it.
 Also go up to every modified FE or FC regardless whether its a 6 or an 8 and look at every detail and compare them all to how you would do it then ask as many questions as you can no matter how stupid they might seem , trust me this can save you heaps of money. Anyway thats enough of my rambling. If you need any help or need to look at my FE just give us a yell,
                            cheers     Scott (GOA350)

[TorqueFC]

thanks scott

we were having a few discussions at our house tonight. as some of you may know we have a 307 here thats got fully ported heads and manifold. the motor hadnt even done 5000 km's before we bought it.  we were at a mates place and started talking, anyway we noticed the motor and well for such a complete motor $1000 was reall cheap.

anyway scott could ou possibly send me some pics of your engine bay and any chassis mods ou have done, also possibly some information on your engine.

cheers
torque

[TorqueFC]

scott

spoke to pavtek today

wrote it down wrong

i meant to say that wed more than likely be using the racer pro heads as they are the ones that produce over 700hp

sorry for the confusion

cheers
torque

[propig2003]

dudes, brett (propig) here. just before chrissy last year, went and had a chat to bob fisher about supercharging the old girl. already running the 400 chev, was advised to use a 350 010 block as it would be around $4000-$5000 bucks cheaper as the internals for the 350 are readily available off the shelf whereas the 400 bits have to be sourced from the states if they are available at all without having to be machined up. suggest ya contact bob at fisher automotive who will be more than helpful in ya concerns.

cheerio
brett