I'm with
A7M. Any turbo will always give any amount of the power you want. You work within a restrained budget, and cost up 350, 400, 500, 600, and 700 flywheel hp, and see if your not broke at the end of each one!.
For each dollar spent, a turbo is money for jam. It's main problem is greed, and buiding the pipes and bits to take the power within your budget. It's easy to leg blocks, pistons and run main bearings and cams if you don't build the engine to suit each level.
Nitrous is just a stage one turbo system, and doesn't factor in most peoples minds. You can't go more overboard than half the existing power extra 'cause it just detonates pistons. So a 240 hp engine can become 350 hp easy, but not 400 hp
On the pessimstic side, there's a bag load of items that make me see $$$.
1. Firstly, it needs to be built to a purpose. It doesn't have to be al things to everyone, it has to suit your goals.
2. I don't like manual drag cars.Way too inconsistant unless you can rig up some kind of ABS operated launch control system or perhaps a disk brake on the drive shaft. In the future, these may preload the tendancey to loose it on the line. That's why I'm like 95% of all RWD drag racers and I like autos, (four speed autos actually),
3. I don't like the stock 200 rods, the Pontiac 400 or 300 I6 Ford are hell for stout and cheap if you can find a friendly American or laid upo Poncho.
4. I don't like the thinner acl race pistons under lots of boost. (You will run lots of boost becasue no-one does the work you've done to sit around and moan about a lack of hp!)
5. I don't like the expense of dialing in the EFI. (Goes with the territory when you play auto manufacturers).
6. I don't like the kind of exy fabricated exhast set-ups the drag racers use. I think the stock set-up is the best for long term durability, and there is little to stop you fitting a BA set-up if you add a 9.5 mm spacer. Just enough room for plugs, and if you use a low mount C4 V8 block adaptor, you can fit it up. (Shameless plug on a project I'm working on)
My first thinking is let's shove it through the
Falcon 6 Performance computer as it is.
Currently, with what I guess is the standard aftermarket 62.5 thou spacer, and two 41 thou Permaset gaskets, you have
Input Values:
Number Of Cylinders 6
Bore Diameter [inches] 3.71
Stroke Length [inches] 3.91
Combustion Chamber Volume [cubic centimeters] 35
Head Gasket Compressed Thickness [inches] 0.041+0.0041+0.0625 = 0.1445
Head Gasket Bore Diameter [inches] 3.81
Piston To Deck Clearance [inches] 0.016 (most X-flows sat at this)
Select Piston Type Dished
Dish/Valve Relief/Dome Volume [positive cubic centimeters] 3.0
Volumetric Efficiency: 95%
RPM (at maximum power): 5500
Displacement, [cubic inches] 254
Displacement, [liters] 4.2
Static compression ratio 11.2:1
Cubic Feet per Minute required @ 5500 rpm, [cfm] 383
Estimated Horsepower @ 5500 rpm
Assumes altitude of sealevel, barometric pressure of 14.696 and 60° air supply to carburator = 276
Considering your getting 181 kw, thats about 240 hp at the flywheel. I'm certain there is another 36 hp hiding somewhere if you rework the electronics and ignition system.
There could be 400 hp there with a nitrous bottle and a further drop in compression, but with a SR 4 box, it won't take the punishment or drop the quarter mile times as much as a good C4 with 2300 rpm stall will.
My cost effective way to B-I-G hp.
I'm not an expert, and if this offends you, then send hate mail to my adress in Dunedin.
First, I'd look at converting to the EF intake runner base. There is nothing different between the 1994 Coon and the 2005 item in the major casting. Or use the Nismo item used on the latest 1500 hp XR6 Turbo.
You will then have the same intake as the latest 240 and 270 Barra. Why not get the Ford standard part BA turbo manifold, add a big 9.5 mm steel plate gaket, and adapt it like you have done to the intake? Run the GT45 or a big TO4.
Do a simple decompression job, with a copper or straight steel spacer gasket dry decked to both block and head.
As i've said, I don't aggree with the 200 rods, or the pistons. Not at the 650 hp level. Each has a limit of strength. I'd look at Pontiac 400 rods, or the 300 I6 rods form Yank trucks.
There is no way a 35 cc chamber is going to give you the c/r you need. I'd just get some T356 alloy laser or profile or cnc machined cut to gasket shape suit, and weld and and aradite it to the existing head, and bring it back to the 58 cc chamber you need. I don't care if it ends up bathtubed at all.
The head could stay fixed with the current gasket set-up, but I wouldn't use that sutuff. In my opinion, needs to be dry decked, and a nice 145 thou copper gasket plate with Moroso fire rings biteing up to the top and bottom.
Don't worry about the lack of good 'o' deck if you use a thick plate to get the compression back. Who cares if you have a piston parked 125 thou below the head anyway if the compression is too high?
If you can get the compression to 8.6:1, it won't be a nasty sucker on 98 octane.
After all that, you can dial in a bit of boost (18 to 22 psi), some intercooling, and then be sure to add a great auto to you block. There should be 650 hp there if its tuned right.
And forget 3-speed autos. Look at fitting the the 4R70W or AOD-E or even a worked THM 700 there. Stick with the 24" tall tyres, add a set of 3.27:1 hyrdratrack gears, and it'll criuse at 2000 rpm at 110 clicks with the converter locked up, and then glide through the traps at 130 mph (210 clicks) at 6000 rpm in third.
Street cars that race are the biggest turn on a car addicted guy could have. One you can cruise to the drags with, and then shut down the oposition with.
Why want something you can't have when with your skills, you can use the factory gear and get all the grunt without spending 10 grand plus on fabrication?