CQ center armrest installed. pic

[3bAudios]

could i get some more info on this seadoo? pics perhaps? sounds like a cool machine!!

[speedydtp247]

:bump: its back up and running

[SteveAngry]

:bump: its back up and running

Any other news?

Did he figure out the boost issue?

Steve

[speedydtp247]

:bump: its back up and running

Any other news?

Did he figure out the boost issue?

Steve

yes he figured out the boost issue. i'll let him explain what he found

[pkw]

So the car developed a boost issue- a rather mysterious one. I tore the thing apart and found that the flow diverters, of the exhaust at the crotches of runners 1 & 2 and 2 & 3 failed.....these diverters were continuations of the runner walls and directed the flow inside of the collector area towards the t3 flange....THE DRAWING CLEARLY SHOWS THESE TO BE WELDED TOP AND BOTTOM, but they were not :slap: so they could not transfer their heat to the top and bottom plates and they could move like a fluttering reed from exhaust/ blow-torch like pulses, until they fatigued themselves enough to break off and partially block the opening of my t3 flange....these pieces were too big to enter the turbine. I guess I got what I payed for from my welder buddy. . so now it is up an running and doing okay. Only 25 psi for today but tomorrow could bring 30+. I am really not seeing any signs of being close to the edge yet. So the manifold seems to be holding up fine and looking good other than ridding itself of the above mentioned "unneeded" design features. I really am pretty happy with the power delivery of this engine. the whole combo is pretty sweet. IMHO

[pkw]

manifold and the turbo support bracket. I figured the mani would grow about .09" from EGT. I made a bracket to support the weight of the turbo in a vertical plane (compression so it would not require a thick plate) and mounted it to the engine mounting arm. It used a piece of thicker bar for a base with a thinner piece of sheet steel welded to it that can act as a reed. It is then mounted with .045 preload while the manifold is cold so that it can flex plus/minus .045 max. from its static position as the manifold temp goes between full hot and full cold....at least in theory that is all figured out :wink:

[pkw]

pic

Attachment ( 18545 ) : parts 002.jpg

[pkw]

bracket pic will follow when Speedy sends it to me again but in a less than 2mb version so that i can upload it. Anyway, today Paul (speedydtp247)and his friend Joel stopped over to look at some cars and we took the coupe and some other little black car out to damage the neighborhood. We had some fun. I really want Joel to bring his urs6 with 3071 over so I can test drive it.

[SteveAngry]

I wish I didn't have to work or I would have stopped by also. :(

Steve

[speedydtp247]

bracket pic will follow when Speedy sends it to me again but in a less than 2mb version so that i can upload it. Anyway, today Paul (speedydtp247)and his friend Joel stopped over to look at some cars and we took the coupe and some other little black car out to damage the neighborhood. We had some fun. I really want Joel to bring his urs6 with 3071 over so I can test drive it.

pics too big!? you fogot to mention that you fixed that mani plug. is it running 30 psi now?

[bimmerboy]

What're you running for a redline, I imagine the short rods and heavy rotating assembly limit that bit?(not enough to really make it not worth though!) And have you dyno'd yet?

[pkw]

What're you running for a redline, I imagine the short rods and heavy rotating assembly limit that bit?(not enough to really make it not worth though!) And have you dyno'd yet?

I am sure. Once at target boost the shape of the powerband is the same as a 7a but with 2 or more times the tq at the points. When I have time to shift, 7k works well and is my fav. point, but is it not very picky 6500-7200 is all good.

[pkw]

bracket pic will follow when Speedy sends it to me again but in a less than 2mb version so that i can upload it. Anyway, today Paul (speedydtp247)and his friend Joel stopped over to look at some cars and we took the coupe and some other little black car out to damage the neighborhood. We had some fun. I really want Joel to bring his urs6 with 3071 over so I can test drive it.

pics too big!? you fogot to mention that you fixed that mani plug. is it running 30 psi now?

shrug, gauge only reads up to 30 psi.

[pkw]

And have you dyno'd yet?

butt dyno says 150hp more than pauls 20vt cq. :wink:

[bimmerboy]

Wow. Overall sounds like the way to do if you don't need an all out build. And plus you can break it without losing much!

[pkw]

yes, to me it made too much sense - I had to do it. If anyone is in the area and wants to take it for a drive (maybe not my neighborhood this time) that is fine. Paul, Joel & Larry have had their way with her.

[speedydtp247]

shrug, gauge only reads up to 30 psi.

time for a new gauge!

And have you dyno'd yet?

butt dyno says 150hp more than pauls 20vt cq. :wink:

150hp? your being a bit conservative. the last time i was in you cq it felt like 200hp more.

we need to make a little vid clip of your cq.

maybe not my neighborhood this time

thats for sure. they must hate you by now? i think the industrial park area near the highway is a good location i think.

[Noisy Cricket]

Okay, maybe I'm just slow... 7A top end, MC2 shortblock, and the pistons are just machined for proper piston-deck clearance and valve clearance?

That's unreal. And awesome.

[pkw]

Noisy Cricket wrote:[/quote]

Okay, maybe I'm just slow... 7A top end, MC2 shortblock, and the pistons are just machined for proper piston-deck clearance and valve clearance?

That's unreal. And awesome.[/quote]...pretty much and the block was machined the same amount as the pistons too....the idea was just to eliminate some of the huge dish. Plenty of material above the top ring land to do so.

[parkerAAN]

Noisy Cricket wrote:

Okay, maybe I'm just slow... 7A top end, MC2 shortblock, and the pistons are just machined for proper piston-deck clearance and valve clearance?

That's unreal. And awesome.[/quote]...pretty much and the block was machined the same amount as the pistons too....the idea was just to eliminate some of the huge dish. Plenty of material above the top ring land to do so.[/quote]

could it work as is? the reason i ask is that a friend of mine is using the mc1 pistons/rods in his vw 1.8 16v turbo and aside from the very low compression ratio, it has been running great for years...

[pkw]

Noisy Cricket wrote:

Okay, maybe I'm just slow... 7A top end, MC2 shortblock, and the pistons are just machined for proper piston-deck clearance and valve clearance?

That's unreal. And awesome.

...pretty much and the block was machined the same amount as the pistons too....the idea was just to eliminate some of the huge dish. Plenty of material above the top ring land to do so.[/quote]

could it work as is? the reason i ask is that a friend of mine is using the mc1 pistons/rods in his vw 1.8 16v turbo and aside from the very low compression ratio, it has been running great for years...[/quote] i think that you answered your own question. the mc2/7a combo gives about 6.8-7.0:1 cr iirc. It was worth it to me to try for something a little better cr wise but even as is it should be worth doing. I would not bother using mc1 stuff though. Mine is a little soft off of boost but it comes on quickly and has better usable power than a stock 7a even if making the comparison at sub 4000rpm levels. 7As are doggy at all rpm, at least mine starts to go somewhere as low as 2500-3000 rpm.
remember though that I still use the 7a intake with its long runners for helping low rpm power. If I had given that up I may be less happy with this combo...they probably cost me 5% up top though. I will try to sleep at night.

[pkw]

BTW...thumbs up to the 7a throttle body making this power easy to control in corners too. The best high output turbo car I have driven without any electronic computer controled crap trying to help it.

[parkerAAN]

if i remember correctly, it was 6.8 with a MC1 and 7.4 MC2... 7.4 is not great but not that bad. the 16vt that my friend has is really not that bad to drive even with the MC1 pistons, he has a t4 on it right now i think. it was making low 300's at the wheels last time he had it on the dyno

[pkw]

Just a data point... c5 auto vette racing from its not sweet spot at 40mph which happens to be my sweet spot...raced a couple of time and eveybody agrees it really was not that close. I backed off at probably like 110 but I am sure that the vettes strong point is at higher speeds. I am not sure how things would have gone if we would have taken off at 90mph..vettes other sweet spots are at 30, 65 and probably at some point beyond that again. They are rated at an honest 345hp fwiw.
just a data point
my cq is running 27-30 psi at the moment

[pkw]

... fwiw lets say 360ish hp for my CQ