Compression?
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From: Woodstock Ga.
Compression?
I was wondering what the cr would be w/ a US 4.5L w/ euro big valve heads?
Would the pistons need to be cut?
Finally, would I need a euro intake?
I am attempting to upgrade to a complete euro top end as time and money allows. I would be starting w/ heads and cams and intake if I need it.
Stephen
Would the pistons need to be cut?
Finally, would I need a euro intake?
I am attempting to upgrade to a complete euro top end as time and money allows. I would be starting w/ heads and cams and intake if I need it.
Stephen
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From: Orange, Cal
A complete running Euro S motor will be cheaper than buying top end parts and putting them on your 4.5 with the cost of head gaskets etc.
If you choose to spend the extra money, assuming it works, putting a head designed for a 97.5mm bore on a 95mm bore engine, the compression might turn out a bit less than for a stock US head.
If you choose to spend the extra money, assuming it works, putting a head designed for a 97.5mm bore on a 95mm bore engine, the compression might turn out a bit less than for a stock US head.
Racer
Joined: Jan 2009
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From: Adelaide South Australia'79 5spd twin turbo
Hmm, interesting concept, the top end of the "euro"engine is what makes the horsepower difference.
Although as Danglerb alludes to, your compression ratio is likely to actually drop, therefore it will be substantially lower than the "euro" compression ratio.
You would want to use the complete "euro" top end as the manifolds are larger, in theory you should be able to see a larger flow improvement on a 4.5 litre than on a 4.7, as the Euro top end was designed for the 4.7 therefore it is slightly oversized for a 4.5.
I'd be curious to see what improvement would be seen by simply fitting "euro" cams to your engine?
Cheers Roy
Although as Danglerb alludes to, your compression ratio is likely to actually drop, therefore it will be substantially lower than the "euro" compression ratio.
You would want to use the complete "euro" top end as the manifolds are larger, in theory you should be able to see a larger flow improvement on a 4.5 litre than on a 4.7, as the Euro top end was designed for the 4.7 therefore it is slightly oversized for a 4.5.
I'd be curious to see what improvement would be seen by simply fitting "euro" cams to your engine?
Cheers Roy
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From: N NJ
C/R would remain the same installing Euro heads. The pistons don't need flycutting for the valve relief. And yes you need the whole package to see some gains: heads, cams, intake, then exhaust.
A healthy 4.5L with this combo might see 260-270HP. If your after raw power consider an S/C.
A healthy 4.5L with this combo might see 260-270HP. If your after raw power consider an S/C.
Thread Starter
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From: Woodstock Ga.
I am thinking of this in stages. At this point I am thinking of doing cam's first. Then get her dyno'd.
2nd mod would be Euro heads and then get it dyno'd.
The last step would be euro intake,tb,etc and get it dyno'd
Then boost!
Stephen
2nd mod would be Euro heads and then get it dyno'd.
The last step would be euro intake,tb,etc and get it dyno'd
Then boost!
Stephen
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From: Philly PA
Steve you will be better off doing as others have instructed get a 4.7 L Euro S engine and drop it in then your starting off with a 300HP engine, replace the head gaskets before you put the engine in
Thread Starter
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From: Woodstock Ga.
Mrmerlin I believe that the advice you and others are giving is the best hp/$ ratio. That said I just want to see what I can do with the car the way she came. I feel like if I just swap motors she won't be the same car. If a car has a soul(lol) she will be gone.
I am by no means trying to set any hp records. It is a 4.5L I do believe that it is a wonderful motor and she is a blast to drive w/ headers and a duel exhuast. I want to she what I, we can coax out of her.
I can buy a set of used heads and cam's w/ my tax return and I will have money for paint by then. So she will be in pretty good shape.
I might not even end up boosting her as the power level that I will get from a euro top end will be should be noticable and a lot of fun having the extra ponies. But then again it won't reach my target goal of 350rwhp.
4.5L motors are cheap in comparison to be had, they have a great CR if you do decide to boost and having one is a little from the norm which I also like. I don't have the funds to just boost her but I do have the funds to buy a set of cams and she what happens. It is all in the journey for me not just the end result.
Stephen
I am by no means trying to set any hp records. It is a 4.5L I do believe that it is a wonderful motor and she is a blast to drive w/ headers and a duel exhuast. I want to she what I, we can coax out of her.
I can buy a set of used heads and cam's w/ my tax return and I will have money for paint by then. So she will be in pretty good shape.
I might not even end up boosting her as the power level that I will get from a euro top end will be should be noticable and a lot of fun having the extra ponies. But then again it won't reach my target goal of 350rwhp.
4.5L motors are cheap in comparison to be had, they have a great CR if you do decide to boost and having one is a little from the norm which I also like. I don't have the funds to just boost her but I do have the funds to buy a set of cams and she what happens. It is all in the journey for me not just the end result.
Stephen
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From: Stockton, CA
with a goal of 350whp....it will be difficult to reach with a 16V normally aspirated engine without significant changes... A 5.0L bottom end with euro heads-valves-cams-intake will make 300whp with ease....but if you want the extra 50whp...it will take some pricey parts..like overbore block-pistons, stroker crank,etc....all are proven, but none are cheap...
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From: Cambridge, Ontario, Canada
From what I heard, only changing to Euro cam will move the torque ban up about a 1000. So you will feel a loss off power in the middle of the rpm range and a bit of boost at the top. For street use, you are better off keeping the stock cams. Or buy the cams now and when you have enough money, buy the heads and install both at the same time.