405 sri 2.0 downdraft head tuning

[pug 405 sri x4 0]

hi too all im building a specific engine with various parts from various engines im wondering if there is anybody on here that tunes this perticular cylinder head and what can they do and cost. thanks in advance chris.

[calvinhorse 870]

Isn’t this the 1.9 ally block? 

 

If so some people have used the 2.0 8v head as they have larger valves and bigger ports as standard, they need a fairly large skim to get the compression up but there has been some good results with a mild cam.

[pug 405 sri x4 0]

hi fella my plan is to use the xu10j2te block xud11 crank forged rods/pistons 405 sri 2.0 head inlet, turbo technics manifold a gtx 2871r turbo. i chose the head beacause of its down draft configuration. i found a post on the web thats on this site but ive searched the site n can not find it. so i made a new post hoping some1 would cherp up but no success yet.

[SRDT 146]

Here:

 

[pug 405 sri x4 0]

yes fella i found that post on the web im trying too find out who can tune the head and what they can do and price.  i typed in the exact post title but still gives me nothing lol just 900 plus pages too search . just looking at it now maybe its cuz im not using cap on some of the txt ill give it another go now.

Edited September 7, 2019 by pug 405 sri x4

[jackherer 543]

Click the link above or copy and paste this text:

 

www.205gtidrivers.com/forums/topic/57408-downdraft-sri-head-vs-205gti-head/

 

 

[pug 405 sri x4 0]

 fella i found that post on the web im trying too find out who can tune the head and what they can do and price.  

[pug 405 sri x4 0]

heres a dummy build of the motor but using the ally mi16 4x4 block

[pug 405 sri x4 0]

turbo manifold, turbo hotside. camshaft cover and inlet plenum will be hpc coated so it`ll look sweet and have purpose

 

Edited September 15, 2019 by pug 405 sri x4

[wicked 103 3 Cars]

What's your target? High big end power or nice flat lined torque engine?
And in which car? If you mount the gtx2871r with TT manifold in a 205, it will hit your bulkhead, but think it will be in a 405?

 

For high end power, you  have the wrong manifold. The TT manifold has some good properties, but on high power it will rocket your EGT and on my engine with smaller TD04HL, you'll get too much back pressure and engine will start to knock.  So the head itself will not be the first limiting factor in that scenario. Your cam and exhaust manifold will be the weakest links. 

 

For a nice flat lined torque engine, it's a great manifold; zero lag, compact form factor, cast... etc But then also the cam might be the better choice to invest into and would pick probably the smaller GT28R/GT2560R or GT28RS to have more low down torque. 

Edited September 17, 2019 by wicked

[welshpug 1,621]

needs more valves!

 

dont forget the height difference between aluminium and steel block xu's.

[petert 549]

Please don’t waste the Mi16x4 block. It’s rare as rocking horse poo.

[SweetBadger 91]

19 hours ago, petert said:

Please don’t waste the Mi16x4 block. It’s rare as rocking horse poo.

Interesting - I think I have one sitting in my garage doing nothing.

 

Thought the only difference was one rear engine mount lug is shallower on the mi16x4 block? 

[petert 549]

I think two lugs are missing, allowing clearance for the transfer case. Otherwise identical.

[Sandy 189]

Mark Shillaber (SRD Ltd) did a 1.8 race engine with the downdraught 405 1.9 head about 20 years ago for a hillclimb 306; it was good than and is still going in a 205 now, a couple rebuilds later. There was a picture in Dave Walkers Engine Management book and it was featured in CCC I think too. It had near vertical induction through the bonnet, until someone pointed out the "silhouette" rule infringement and then a curved fabricated inlet. Getting the induction right under the bonnet is tricky, the chamber is a lot bigger than the XU9 and the ports can only be worked out to about 34.5mm bore IIRC, but it's a nice port shape.