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Motor rebuild question

deez

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Joined
May 29, 2004
Messages
1,150
Location
Chico, CA
I am thinking of building a motor for the car, now that it looks like I am keeping it. gotta love the girlfriend that encourages keeping such a car and not getting something more practical /ubbthreads/images/graemlins/smile.gif She enables my addictions. One gripe that I have is how the car runs with the AC running, the car really gets bogged down. So with building a motor, I was wondering if there was a way to build it to have more off boost power? That might help a bit. I looked into stroker motors, but that looks to be a pain in the a**. Any thoughts? And for buying a built head, any suggestions other than Buschur? My last dealing with him left me bitter.
 

TylerAdamson

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Dec 26, 2007
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1,034
Location
Iowa City, Iowa
Others might be more versed in this than I am, but I think a stroker is going to be your best bet if you're wanting better off boost performance.

As for a heads, nearly every shop has a head package available with different options. AMS, Slowboy, Buschur, Magnus, Fox Lake Machine, Modern Automotive Performance, and even a member here does port work. Just do your research and pick the best options that will fit your budget.
 

CarRacer

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Jun 28, 2007
Messages
4,371
Location
Shakopee, MN
Instead of a stroker motor you could look into higher compression. It'll require new pistons but be cheaper than a stroker. E85 would be sweet with a nice compression but not sure of the availability near you.
 

deez

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May 29, 2004
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Chico, CA
We don't have E85 here in Cali. Higher compression may be an option, but how high can you go before it becomes a bitch to tune?
 

TurboTrader

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Joined
Jan 30, 2009
Messages
161
Location
Pemberton, NJ
With the aggressive timing ramp that our stock ECU's put out, without going with ECMLink or a standalone, my recommendation would be stock 2g pistons at 8.5:1 as opposed to the standard 7.8:1.

I've experienced 2g pistons with the stock head, and it makes for some very nice off boost torque without bumping the compression high enough that you will see bad knock with the stock timing ramp.

Anything more than 8.5:1 and you will experience issues with stock timing.
 

Use the 9:1 comp Wiseco pistons. Jeff can compensate for them with a chip so that's not an issue.
 

prove_it

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Jul 3, 2008
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4,201
Location
Sioux Falls, SD
Just be sure to remember that since your rebuilding the engine you will most likely need to shave the head and/or block. Doing this will also raise compression. I put in 8.5:1 pistons and my overall compression is around 8.7:1 after machining the head and block.

You can run 8.5:1 pistons without a chip but I don't recommend more boost or a big turbo. The timing map is very aggressive and has a huge advance spike around 6k. 9.1:1 comp pistons will not work with the stock timing curve unless your running E85 or race fuel.

In my opinion raising compression is the best bang for your buck. Increased low end torque, quicker spool-up, and better fuel economy are the perks.
 

deez

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May 29, 2004
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1,150
Location
Chico, CA
So running 2G pistons with an Evo 16G @ 25psi would be okay? And its a noticeable increase in off boost torque?
 

Ed,
For the price of the 2g pistons + machine work, just get yourself a set of Wiseco 9:1. Unless you can get the pistons free, machine work free I would pass on the stock 2g pistons.
 

prove_it

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Jul 3, 2008
Messages
4,201
Location
Sioux Falls, SD
^1 That's why I went with wiseco/eagle. It only ended up costing me about 150 more. Can't beat it.

No, with a stock timing map and a 16g running 25psi with 8.5:1 compression will not work. It will knock. The map will try to push around 20-25 degrees timing. Big no no.

You will NEED a chip or link.

I build 10 psi by 2600 with my 8.5:1's and a 14b with a stock intake and intercooler. Boost is very responsive and easy to drive. It's great since I auto-cross and I have pretty much no lag. With a 16g you should see about the same, pending on your intercooler size, intake piping and exhaust.
 

deez

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May 29, 2004
Messages
1,150
Location
Chico, CA
So with that setup then, Keydiver can make a chip to compensate for the compression and call it good, correct? And while on topic, what about rings. Are some rings better than others for turbo motors?
 

Ok, last year I spun a bearing and decided to build a Stroker. I also wanted good off-boost response like you, so I went with 9.5:1 pistons also. I was confident goin this route having previous experience using USDM SR20's (9.5:1comp) and T3/T4's at 20psi. They held up great. Yes I had Jeff customize the chip for timing and he did a great job. Ive seen 20psi (Ive pegged my 20psi gauge a couple times so who knows what actual boost was) and no knock.

Off the top of my head the I think I spent about 1500 for everything. I bought rods even though I didnt have to and assembled and machined the block myself saving me some money. All in all I couldnt be happier. Im only goin for a quick street car, I dont plan on doing a whole lot of Drag racing, if any. Im throwin a 3052 in the mix shortly and that should really wake her up.
 

ApexHunter

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Joined
Apr 25, 2007
Messages
1,992
Location
Marysville, WA
Quoting deez:
We don't have E85 here in Cali.



We do. Unfortunately i think the closest source i could find for you though is about 2 hrs south in the sacramento area.....

FWIW my buddy uses e85, and since he lives about an hour from the closest pump he bought a large reservoir he could keep at his house. It would be a huge bitch though if it was for anything other than a toy/weekend/race car and even then you are obviously severely limited in range when you factor this in plus the fact that a tank of gas will only go
 
Last edited:

uncleben4rice

Well-known member
Joined
Apr 17, 2007
Messages
296
Location
antioch ca,
Deez,

Call this guy, His name is Dan, He built my motor, he has lots of DSM engine building experience and is a well known builder in the bay. I have not had any problems for three years with over 40,000 miles on the motor. It has good torque. When I had air, the motor always ran fine even at idle. He could tell you what rings and piston work best. Hope to see you soon.

Peace,


Name: Amaral's Engine Parts & Machine
Street: 45405 Industrial Pl
Postal address: 94538- 6449 Fremont, CA
Phone: 510- 656-9351
 

GVR-4

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Joined
Apr 22, 2002
Messages
2,610
Location
Asheville, NC USA
I'm looking for better low end drivability too. I've been thinking about it for a while and I've come up with seven things that I think will help. I hope to do all of them eventually. I put them in the order I will implement them:

Things to Improve Low-end Drivability

1. cyclone intake manifold
2. liquid to air intercooler (short route intercooler plumbing)

3. higher compression ratio engine
4. bigger displacement engine

5. ball bearing turbo
6. twin scroll turbine housing
7. extended tip comp wheel
 

prove_it

Well-known member
Joined
Jul 3, 2008
Messages
4,201
Location
Sioux Falls, SD
You don't need all that. I'm making about 250ft-lbs torque around 3k with stock 14b/stock boost. Stock intake piping. 2.5inch exhaust.
all I did is 8.5:1 pistons. I do have a cyclone manifold. Those two items made a huge difference. It pulls hard from 2500rpms and I have no issues breaking tires loose.

Compression makes a huge difference. In my opinion strokers are not worth the trouble. It does help the low end, but you'll lose the high end.

Twin scroll turbos tend to crack more easily and in my opinion do not work well for a daily driver because of that.

If your worried about IC piping causing boost lag, then use mandrel bent 2.25" or even 2" instead. Don't use a huge core either. I used a starion intercooler before with 2.5" piping and boost built by 3k easily.
Front mounts are easier to install than a liquid to air cooler.

Well that's my two cents. I really think your worrying too much about this. If your running a turbo around the size of a 16g to a 50 trim you'll still get 400 wheel horse and boost by 3500rpm, even with big pipes and a 2.0L.
 

G

Staff member
Joined
Feb 24, 2004
Messages
8,896
Location
zompton
These guys I hear do pretty good work >> click
 
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