DAW

Thanks, Tony D, I PM'd him and asked about the sonic testing. DAW

The LD28 rod is basically an FJ20 rod except with a larger wrist pin. This is why I question other anecdotal info about the LD28 that I read...that an engine with 21:1 c.r. or so, would have weak internals or thin cylinder walls. I'd sure like to see some sonic testing data. DAW

I have 2 2.8L 10:1 L6's configured differently. One is an F54 flat-top shortblock with an N42 head with headers and triple carbs, and the other is an LD28 shortblock with an N42 head with headers and fuel injection. Both have stock cams. The F54 based engine is prone to spark knock, while the LD based engine is not. I attribute this to the longer r/s of the LD (140/83 = 1.69) vs that of the F54 (130.4/79 = 1.65) and possibly the effect of the pre-combustion indent in the head of the LD piston (the clover-leaf thing, it is named after someone...). The LD based engine has an abundance of low end torque vs the F54. The LD is in a Maxima and I'm using the original 3spd A/T with lock-up torque convertor. The diesel torque convertor has a lower stall speed than even a gas Maxima but the response off idle is impressive. The F54 is a M/T so it's a little hard to compare, but it doesn't seem to have the low-end torque that the LD produces. I'm reluctant to turbocharge the LD based engine because I think the N42 head will be prone to detonation, but I'm thinking a low pressue intercooled turbo (even at 10:1 c.r.) may be the next step. I'm not looking for high rpm power, but for maximum torque from this engine. If I ever get around to it, I'll put together an LD shortblock with longer rods, flat top pistons, overbore, and a high quench head (P90) to extend the rpm capability some and preserve the off-turbo high torque characteristics. I hear so many anecdotes and myths about the LD bottom end but very few personal empirical accounts from anyone re hybribization for gas use. I put together my LD28/N42 combination 12 years ago and it's been a daily driver and a ski car over the years. Last year an Expedition made a U-turn into me and totaled the passenger side. It still drives fine but is an eyesore. Ultimately, I was going to put together various LD-based gas engines with various configurations using the Maxima as a test mule before pulling them to convert to rear sump and transplant to a Z car...but I don't have the time these days. Some info I could use though is some RELIABLE, accurate data re sonic testing of cylinder wall thickness of the LD28 block; not heresay. DAW

Or, since you have some $$ invested in your triples/header/etc., you could use an N42 head or a late E88 head and have 10:1 c.r. which will definitely wake up the power...but these heads have a tendency to lead to detonation even with a reasonable amount of spark timing advance (and you'll want to run a bigger cam too). The closed chambered heads like the P79 and P90 run with flat top pistons tend to circumvent these detonation tendencies. But all things considered, either run pop-up pistons/P90/triples; or flat-tops/P90/turbo. The turbo is cheaper, sell your triples and just find a stock 280ZXT and take the whole turbo manifold/turbo/injectors/intake/ECU/distributor and intercool it on your P79 shortblock, and you'll be happy with the result. DAW

The P90 is a turbo head. By replacing your P79 with a P90 (more cc in combustion chamber) you lowered your compression ratio and reduced the power of your engine. At this point, consider turbocharging the setup you now have. You will have increased static c.r. as compared to the OEM turbo (P90) spec engine, but if you intercool and limit boost, and run Knock sensor, it will be a nice combination. (and it has a nice squish factor re the flat tops and chambered P90) DAW

I have an E31 with a fresh valve job and the larger L28 exhaust valves installed. Very reasonably priced in Seattle. DAW

OK, so you won't have a piston-to-valve check until you've already had the machine work done on the head (BTW, did you include N42/N47 valves in your formula/solution there?...you'll need these if you cut 0.080" from the head/shim the towers)...I'd say go for it...the worst case scenario is that you have to fly-cut the pistons...and that's not the end of the world to do... DAW

Check the piston-to-valve clearance and you'll know. Read any HotRod magazine for discussion. DAW

With a used chain and sprockets and a clean-up cut on the head, you may be in sprocket hole #2 to get the cam timing right. If it's a toss up between #1 and #2 holes, I recommend #2 since that is the direction that wear is going to take you. DAW

Found one. Thanks Scott! DAW

I need the bracket that bolts to the block. DAW

I need one pulley. DAW

The things rolling around are supposed to be there, they stop sediment from forming. DAW

I was planning a rear-facing TB, but all things considered the whole idea makes less sense than a FMIC. It would be a lot of work for no gain in performance. DAW

Heat soak would be a big problem if the intercooler is mounted centrally over the engine, but I was thinking of locating it on the right side of the engine bay and isolating it. On the other hand, maybe it doesn't make sense and I should stick with a FMIC. DAW

I figured this was as good a forum as any for this: project to fabricate this set-up. Must include a custom hood, a custom intercooler, plumbing, and performance parameters (e.g., mount on cooler, right side of engine bay; or not). First step is to have a look/see at the engine bay re intercooler positions. It would be cool to mount the intercooler in a separate stainless steel compartment to handle the cooling air flow. Maybe a fan will be included, one that will freewheel well at speed and maximize flow (when off). DAW

the same basic rule applies. I recently had a soft pedal on my 510 and it turned out to be a bad rear wheel cylinder and NOT the master cylinder (of course I discovered this after I had already bought online the master cylinder rebuild kit). DAW

Almost any leak in the system could give that sign (push fast is firmer than push slowly). However, if you are losing large amounts of fluid it could also be a bad wheel cylinder or caliper, or a loose bleeder screw. The pathognomonic test is to push quickly to get a firm pedal, then ease up a bit on the pedal pressure - - if the pedal now drops when you eased up; then your master cylinder is defective (and you may find some fluid in the dust seal on the master; or soaked into the paint and your carpeting under it). DAW

Are you losing fluid? DAW

Why not put the whole carb set-up in a custom built plenum so that pressure is equalized? That's how Maserati did it (but with only one, progressive, carb). The priciple is the same: fewer air pressure differential problems; i.e., boost carbs and all as an environment...You would want noncollapsible floats here... I have a later model Biturbo with efi so I can't say from personal experience how the blow-through in a box works on the road (my fi Biturbo hauls a**, though) DAW

I'd guess Volvo RWD series from the appearance but I have no idea re dimensions. The rear bar on the volvo bolts on like that to the rear lower links. DAW