The V8 Owners Forum -

Ultimately the compressor map isn't that important here.

You have the blower you have, that isn't likely to change. So assuming it is in good order, check the essentials. A D1S-C is capable of making power.

So, Check there are no air leaks in the system. This means pressure test the entire system from volute inlet, to intake valves. Resolve any leaks.

Belt slip. As you already know engine rpm and gearing....affix a small tooth to the blower pulley so you can point a sensor at it to get a blower speed pickup. This will let you know if there is any belt slip, and remove all doubt about that aspect. And it can be one of the most problematic ones. So rule it in or out.

It could also be worth pressure testing the system whilst in operation as I already described, with at minimum a pressure sensor before and after the intercooler.

Get those basic fundamentals sorted before going nuts with anything else.

I was trying to show that just because a spec sheet shows a max number of air flow or power of 600(pick your number)HP - doesn't mean it will make 600 on your engine.

You will probably need to achieve quite a high pressure ratio to get 600hp out of a restrictive flowing engine like the Rover V8.

SuperV8 wrote: ↑

Mon Jan 25, 2021 8:46 pm

I was trying to show that just because a spec sheet shows a max number of air flow or power of 600(pick your number)HP - doesn't mean it will make 600 on your engine.

You will probably need to achieve quite a high pressure ratio to get 600hp out of a restrictive flowing engine like the Rover V8.

Absolutely, RV8 doesn't really flow a huge amount of air, so it will need a decent amount of boost to get there, although that also depends on blower size.
And of course with a blower...you need to factor in driving the blower itself takes power.
So 600hp measured or estimated at the flywheel...in reality might take an actual 650-675hp as 50+HP could be needed just to drive the blower.

Don't obsess about numbers. Ensure it is all healthy, ensure there is no belt slip or leaks...and enjoy. If it needs more, spin the blower faster. I doubt almost any RV8 will exceed the abilities of a D1SC

Just looking at your pulley setup - doesn't seem much difference in your sprung tensioner between slack and tight.
Does it have enough swing before it hits the end stop? As your pulleys take power from your belt (especially the supercharger) they stretch the belt - so the sprung tensioner will need to move and take up this slack!

Have a look at some videos of superchargers and sprung tensioners and the amount they can move under boost!

SuperV8 wrote: ↑

Thu Jan 28, 2021 4:37 pm

Just looking at your pulley setup - doesn't seem much difference in your sprung tensioner between slack and tight.
Does it have enough swing before it hits the end stop? As your pulleys take power from your belt (especially the supercharger) they stretch the belt - so the sprung tensioner will need to move and take up this slack!

Have a look at some videos of superchargers and sprung tensioners and the amount they can move under boost!

Yep, I've posted about that before. They stretch a surprising amount, and the tensioner needs to have enough strength and range to maintain tension throughout. Usually the belt will need to be an extremely tight fit in the engine off position. And it needs a good strong tensioner.

well we bit the bullet this year (late 50th bday present) and had the shell sent away for restoration, scary whats found under seemingly good paintwork etc,

Current state with the car as of yesterday after 5 months of panel work

Not cheap to do by any means, but needs must. Rust just gets everywhere ! Hopefully that'll be it sorted for many years to come.

Ideal time to sort arches etc for additional tyre clearance where necessary.

I did a lot of repairs to mine during the lockdowns, seemed ideal time as nowhere to race etc. But trying to cut out old rust and replace is just a nightmare, even more so when some was around the caged areas.
I didn't go as far as a full strip down though.

That's major work there !

It always worries me that even the most skillful repairs will not last as long as when Ford built it in the first place. Getting the right paint, getting it to stick, getting it to seal against moisture, etc. etc.

Dunno what the answer is though (apart from have a Land Rover where it can all be replaced!).

Chris.

ChrisJC wrote: ↑

Mon Aug 29, 2022 3:47 pm

It always worries me that even the most skillful repairs will not last as long as when Ford built it in the first place. Getting the right paint, getting it to stick, getting it to seal against moisture, etc. etc.

Dunno what the answer is though (apart from have a Land Rover where it can all be replaced!).

Chris.

I think a lot relies on ensuring all work is done in a clean, warm, dry environment. And also treat any rust with a suitable rust killer...that isn't always so easy though.

I injected stuff into the sills, and gaps etc I could find. Hopefully it will help, but time will tell. I know there are some areas under paint I should have done better, and already just over a year on a few bubbles are re-appearing. Not structural, but very annoying. But my garage is not heated, and over winter whilst dry inside, the atmosphere can be damp. All this was before painting, although I did have a lot of it done with epoxy primer.

Under some rusty bits under the scuttle/wing are where there were multiple layers of metal, some actually were full on bare steel. Just trapped from new, and they were still like new. Outer layers were bad though

A little update, after nearly 6 months of panel work and rust removal top coat has finally gone on
car will be coming home soon for me to start refit work while they concentrate on the panels left to prep and paint,
once im done the car will then go off to have the new exhaust and manifolds made, the car will then go back to Browns for final panel fit up and then flat and polish,

Long road ahead still. Lots of patience needed.


I opted for fibreglass wings. Mainly as at least they won't rust again !! lol

But they were an absolute ton of work to get to fit half decent. No idea why, but they were just a bit wrong everywhere.

Looking good Coops!

Car finally came back on the road in October 2023 after 2yrs away being restored,
Custom stainless manifolds and system built on the car in September 2023 by Rich's Fabrication Nr Grove Oxon, My Sons ST Fiesta, My Daughters Swift and my Capri at a local breakfast meet in October,

Must feel good to have it back on the road. All shiny shiny