| Author |
Message |
    
Ali
| | Posted on Wednesday, July 24, 2002 - 09:36 pm: | 
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Anyone got these laying around? How about a cam shaft too? Building up a 4.6 engine for my '91RRC.
Thanks. |
hendrik
| | Posted on Thursday, July 25, 2002 - 08:05 am: |
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Ali,
why is it the 4.2 parts you´re looking for ?
(compression ratio ?; quite possible to put 3.5 heads and intake manifolds etc on top of a 4.6 block. With composite gaskets you will get a slightly lower compression ratio than 9.35:1) |
John C.
| | Posted on Thursday, July 25, 2002 - 08:20 am: |
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Ali, I'd be interested in learning more about your buildup. I have a 4.6 (valve covers to oil pan) sitting in my back yard waiting to be worked on. Any info would be greatly appreciated.
Thanks.
PS: It's gonna replace a 3.5 |
ali
| | Posted on Thursday, July 25, 2002 - 06:44 pm: |
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Hendrik & John,
I'm still learning, so here goes: the 4.2 heads and intake are more efficient than the 3.5 and 3.9 from what I've gathered. Currently I have 3.9L running in my '91RR but am simply looking for a wee bit more torque at low rpm. I've been reading about Buick 300 heads and other crazy stuff for high hp "improvements". However, I need loads of torque at the 1400-3000 range for better "crawlability" and mountain pass crossings. As you know, slapping all sorts of aftermarket hi-po stuff not only gives you more power but more headache as well! I'd like to use the stock 14CUX ECU with all OEM stuff that's already there. Prolly have to go to a rising fuel press regulator too.
If I do find a set of 4.2 heads, they will be rebuilt and ported/polished only to "optimize" the whole system. I understand they port match to the exhaust manifold quite well already. If no 4.2 then I'll yank mine out and do the same thing. Again, I'm not looking for a hi-po engine but simply want to max out on everything while maintaining reliablity and driveablity. As Craig H. once suggested, a cold start EPROM chip will be going in there too unless there's something else out there. Bottom line is that I don't want to drive around with a laptop adjusting all sorts of shiat! |
Craig M. Highland (Shortbus)
| | Posted on Thursday, July 25, 2002 - 11:13 pm: |
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Polishing? Yes-
Porting? Not so sure about that on an engine built for torque. I would look into some custom velocity stacks on top of the intake that are not only longer than stock, but of equal length. Ever seen the new M5 intake, or a Bosch Rover intake?
Have fun, it's worth it....
Craig |
Drew
| | Posted on Friday, July 26, 2002 - 08:02 am: |
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just use your 3.9 intake and heads, their is not much differance. the cam however go with 4.2 or an aftermarket one. |
hendrik
| | Posted on Friday, July 26, 2002 - 09:53 am: |
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Thought I posted something ... lost in silicon valley somewhere I guess.
Ali, watch the www.rpiv8.com website. Always a good starting point in these questions.
Lots of information regarding the Rover V8. |
Larry Grubbs (Larryg)
| | Posted on Friday, July 26, 2002 - 11:11 am: |
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Rumor has it that some people are using the Crane cams for the 4.6L buildup. They use the cam out of the Buik 215(?) I think. You can get one of these optimized for a lower torque curve. And it is much cheaper than the Pipers and the such, about $150ish I think.
Larry |
Ali
| | Posted on Saturday, July 27, 2002 - 02:01 am: |
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Yeah, I saw the Crane Powermax cams http://www.cranecams.com/master/apps/rover.htm. Does the rpm range sound good to you guys for torque: 1500-4000? Don't really understand the diff between their "base" vs "cruise" rpm concept. THeir phone lines are too busy.
Another good website is Reemer brothers in UK (not reemer eng). They really break down the whole engine buildup thing, right down to nuts and bolts.
What's the latest price on a 4.2 cam? Somewhere around $400?
Craig, guess it's time I find out what the stacks even look like on my 3.9!!
Thanks for the inputs guys. |
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