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Re: 4,6 Ltr with quad Weber power output
Posted: Fri Sep 07, 2018 9:25 am
by Darkspeed
dyno wrote: ↑Thu Sep 06, 2018 8:05 pm
The inlet manifold I got in the workshop for DCOE is an alloy cross over, so no bents at all and nice long runner . (good for lower RPM). The swan neck manifolds, I don't like at all. Would never try them.
Swan neck would be the only one I would use if I had to use a crossover - The centre ports in the head are so close it is the best way to get a decent diameter of runner to them plus all the other advantages of individual manifolds
Re: 4,6 Ltr with quad Weber power output
Posted: Sat Sep 08, 2018 9:26 am
by dyno
I can not compare with dyno numbers but the manifold I got is the one in this link. I don't think you can find anything better.
http://www.webcon.co.uk/shopexd.asp?id=15266
Re: 4,6 Ltr with quad Weber power output
Posted: Sat Sep 08, 2018 10:06 am
by Ian Anderson
Re: 4,6 Ltr with quad Weber power output
Posted: Sat Sep 08, 2018 4:41 pm
by dyno
From experiences with Pinto (and end few other) engine I do know this sharp turn send the air flow to the bottom of the inlet track. In a Pinto it means 160 Bhp with IDF and the same engine can make 175 - 180 Bhp. Nothing to do with the fact it is an IDF, it's the shape of the manifold.
I've never tested any of them on a Rover V8 but I would go for the lang straight manifold every time. Once we had a Suzuki 1300 on the dyno. It made nice torque and power but only with very long inlet trumpets (fuel injection ITB). Longer as the space we had in the car so we made 4 long turns in the manifold to the right (not even to the top). Power did drop about 5 Bhp and nothing we could do about it. Maybe the pulse tuning was not as strong anymore or the air was pushed to the wrong direction.
As far as I've ever tested, straight inlet tracks where always best.
I hope the IDF setup can make the same power and torque because in the Super 7 replica chassis I wil never find room for Quad DCOE.
Re: 4,6 Ltr with quad Weber power output
Posted: Sun Sep 09, 2018 8:10 am
by Darkspeed
As far as cross-over manifolds go that's probably the best - but it is not the best of inlet manifolds for an RV8 as the numbers come with the downdrafts. It should be good for torque though.
Then again, if being used with stock valve sizes and going the 5000 rpm route there will be nothing to choose but the low end torque may be better with the long runners.
Re: 4,6 Ltr with quad Weber power output
Posted: Mon Sep 10, 2018 11:20 am
by dyno
I would like to know someone who did tested downdraught versus DCOE on a medium or full tuned Rover V8. That would be interesting data.
Hope someone ever done this.