some minor mods

[slideways]

Hi All
i am trying to find a few more horses and was thinking of chipping and a big bore induction/bosch amf and possibly a plenum spacer, the question is how much will i gain from these mods,
i would like to find another 15 horses if possible before going down the sc route, are there any easy mods i can do to achieve this
i'm currently running a 4.0ltr mc1 cam with v8d,s stage 3 heads 72mm plenum and 45mm trumpet,also a straight through exhaust, and it produces 260 bhp 204 at the wheels

Rich

[thegman]

Those are great horsepower figures already. Also how did you calc your rear wheel vs flywheel? As 204 + 20%ish is a long way from 260. I would think that would put your flywheel hp at about 225

Edited by thegman on Tuesday 16th September 16:03

[450Nick]

There's your 15 horses right there! With 6 bonus horses!

[thegman]

i am saying that his flywheel figure of 260 is probably a little optimistic, given the 204 he quotes for the wheels.

[slideways]

had a RR sesion at austec open day on sunday fly 259.2 wheel 204.4 drag 53.7 torque 243.6 but the rev limiter was cutting in at 5815rpm

[450Nick]

Hmm reading that, my post makes absolutely no sense Should have read it properly methinks!

Why do you need 15bhp if you're planning on supercharging the car?

[slideways]

i would like to see what more i can gain before i sc also as im running on a standard ecu and chip and the rev limiter is cutting in early so may be there are some gains to be had there,

[slideways]

Heres the results of the R.R

any thoughts on my original post??
Rich

[450Nick]

I'm not sure how much it would give you, but I'd agree that the plenum spacer and big bore AFM would probably be the way to go seeing as you're going to need these things for the charger conversion anyway. If you're looking to spend a little more, an aftermarket ECU such as Emerald, Omex, DTA etc would give you some good gains and improve driveablility. It would also be well suited to the charger conversion later on as the fuelling can be better controlled than by the Lucas system. They do cost a bit though so I'm not sure if you'd want to pursue this route. Alternatively you could just go with a Tornado Chip and a remap, but you'd have to pay for another remap after fitting the charger so probably not the most economical use of your money.

I wouldn't think you'd gain anything from raising the rev limit as the MC1 cam runs out of puff during the 5's and it will be limited back down to about 5800 with a charger anyway. If it were me, I'd save the cash and get the charger a bit sooner, or do as you say and get bits of the kit now such as the AFM and spacer to spread the cost out and see a little benefit in the meantime.

That's my 2P

[GreenV8S]

Presumably it's already been remapped to suit those induction mods you already have. The figures you've got already seem quite phenomenal, and I'd be surprised if you managed to get much further. The plots show that peak torque is at much higher revs than normal which suggests you have a pretty wild cam. Do you know whether the bottom part of that run was done at full throttle? If it was, it would seem that the cam has absolutely crippled the bottom end.

[slideways]

450Nick said:

I'm not sure how much it would give you, but I'd agree that the plenum spacer and big bore AFM would probably be the way to go seeing as you're going to need these things for the charger conversion anyway. If you're looking to spend a little more, an aftermarket ECU such as Emerald, Omex, DTA etc would give you some good gains and improve driveablility. It would also be well suited to the charger conversion later on as the fuelling can be better controlled than by the Lucas system. They do cost a bit though so I'm not sure if you'd want to pursue this route. Alternatively you could just go with a Tornado Chip and a remap, but you'd have to pay for another remap after fitting the charger so probably not the most economical use of your money.

I wouldn't think you'd gain anything from raising the rev limit as the MC1 cam runs out of puff during the 5's and it will be limited back down to about 5800 with a charger anyway. If it were me, I'd save the cash and get the charger a bit sooner, or do as you say and get bits of the kit now such as the AFM and spacer to spread the cost out and see a little benefit in the meantime.

That's my 2P

Nick
as i've not done any thing with the ecu yet changing the ecu might be on the cards what would an ecu change cost (ball park)
Green v8s
I've no idea how the session was done and dont really know how to interpret the graph i only have an mc1 cam so not lary, the guys at austec were quite suprized at those figures and said they hadnt seen it before in a 4 ltr

Edited by slideways on Tuesday 16th September 22:52

[Inny]

HC?

[slideways]

nope, i wanted the h404 from v8d but they said it wouldnt fit cos i dont have pocketed pistons

Edited by slideways on Tuesday 16th September 23:27

[350Matt]

Definitely go for some aftermarket injection by binning the std afm you'll get about 8-10 Bhp and you'll pick up a lot more than that mid-range and you can control the spark properly.
Its not that expensive either if you can wield a soldering iron all the parts you'll need can be got for under a grand.

After that do you know what static CR you're running? as with after market injection this can be bumped up a bit see

http://www.empirenet.com/pkelley2/DynamicCR.html

for working out the dynamic CR and aim for 9:1.

From my old 4.0 ltr I got wheel figure of 232Bhp so about 275ish at the fly

Matt

[450Nick]

I wouldn't go that route anyway, you need a low C/R and a mild cam for supercharging - an H404 wouldn't work, an MC1 is ok but a better cam still would be an even milder one. I would go with an aftermarket ECU, though it is a lot of work and costs start at around 1K depending on how much you do yourself, which bits you go for etc. Do a search for Emerald on the forums and most of this info can be applied to an Omex, DTA, Megasquirt, GEMS system as well as the Emerald - though Emerald is probably the most bang for the buck I would think.

[slideways]

Thanks for all the input fellas,
V8D told me that composite head gaskets would give me a CR of 9:1 so i'm guessing its a little higher at the moment,
As i haven't had the mapped the ecu to any of the upgrades that i've done as yet i think i'm going to upgrade to a smooth bore intake pipe and plenum spacer/insulator then look at the emerald system, after that a charger looks favourite.

one final question have i missed any little things i can do for positive gains

Thanks again

Rich

[350Matt]

A few:

Reduce the con-rod 'cheeks' to 3 or 4 pads where they rub on the side of the crank journal to reduce bearing area and friction
Balance everything (end to end and rotationally)
Check rocker sweep over valve tip
Ensure lifter preload is correct
Use stiff pushrods (std ones aren't much cop) as there's a lot of power robbing flex at revs over 5K
De-shroud valves in combustion chamber (don't worry this won't drop CR very much especially if you re-skim afterwards)
Lighten the flywheel.
Lag or ceramic coat the exhaust to reduce underbonnet temps
Port match the inlet to the head (often a fair bit out)
Run a decent oil such as silkolene 15W 50
Fit copper colsibro valve guides

Matt

[Chimjunkie]

Quite a few simple things then. Will do those tomorrow