Boxster V8

[mikeman]

Originally Posted by Pdwight

2005 Chevrolet 5 3 L33 Vortec Engine with Computer and Wiring LS1 LS2 LSX | eBay

Less than 350HP

yeh stock...
good little thread over here:

L33 5.3 na performance build recipe - LS1TECH

Here is my aluminum 5.3 build:

18K mile 2007 LS4 (aluminum 5.3 w/799 heads): $1000 for engine transmission/harness/ecm.
LS7 MAF: $60 for sensor and pigtail
LS2 TB, Intake, & Injectors: $375
224/232 DoD camshaft, springs, pushrods: $750
LS7 exhaust manifolds: $150
Reworked stock harness: $50 (for pins and heat shrink)

Never pulled the heads or did any porting, just bolted together and tuned.
So $2385 for the basics, or $1810 after I sold the transmission for $575. Best part is when I break it, I can just get another LS4 engine, swap over the parts and do it again. Resulted in 382whp at 6800 rpm and 335 wtq at 5000

and CarCraft..

Dyno Numbers
Test 1 was the baseline test for the stock 5.3L with a GM Performance Parts single-plane intake manifold, a Holley 750-cfm carburetor, and a set of Hooker 13/4-inch headers complete with a 21/2-inch exhaust system and Flowmaster Super 44 mufflers.

Test 2 was the same engine with the only addition being the Comp Thumper hydraulic roller camshaft.

*snip*

TEST 2
peak HP 433@6800rpm
peak TQ 381@5400-5600rpm

Read more: 325 Chevy Small Block Engine - Bolt On A Cam And Heads And Add 120+HP - Car Craft Magazine

[Pdwight]

That sounds as antiquated as a 8-Track player...Fuel Injection would be the only way to go IMHO

[mikeman]

Originally Posted by Pdwight

That sounds as antiquated as a 8-Track player...Fuel Injection would be the only way to go IMHO

Of course..
for engine dyno testing purposes, as in the article, it keeps it simple and repeatable.

[jb92563]

I like where this project is going and it may just make those rollers worth a bit more with a nice power boost as well.

I have an S and think that by the time you get this all worked out, I might want to consider this option as the engine ages and needs major repairs.

The plug and play wiring and tranny connection aspect is very good.

If you can get the price around $6k or less I think you will have a real winner as all the aging Boxsters start looking for new engines.

I'm curious now and looking for info on this engine and found this:
http://www.clubgti.com/showthread.php?244292-Audi-32v-4-2l-V8-engine

Of Note: Lower Reving ~6800? , Good torque midrange

[Pdwight]

Originally Posted by jb92563

I like where this project is going and it may just make those rollers worth a bit more with a nice power boost as well.

I have an S and think that by the time you get this all worked out, I might want to consider this option as the engine ages and needs major repairs.

The plug and play wiring and tranny connection aspect is very good.

If you can get the price around $6k or less I think you will have a real winner as all the aging Boxsters start looking for new engines.

Totally agree, at 5K or just under it becomes very very attractive...350HP would be plenty for me....my mostly stock S has enough power for me

[kcpaz]

I admire your ambition, but coming from someone who has done what you are talking about doing, I think you have a LOT to learn. Just a few things that come to mind...

- The Audi 4.2 V8 did not start maiking anything close to 350hp until mid/late 2000's, and those engines are pretty expensive to buy still. When you say that you will be using engines from a "similar era" as the 2.5 Boxsters, I assume you are talking about the ABZ engines which are indeed very cheap to purchase, but will NOT make that sort of horsepower without doing a custom build or forced induction.

- There is absolutely no reason to make a custom oil pan or to convert the oiling system to dry sump. Besides, where on earth do you plan on mounting an oil tank? Also, the cost of a custom, low production billet oil pan is going to drive up the cost of the conversion considerably, as well as the oiling system with the pump and all of the plumbing.

- How much research have you done into the chassis wiring integration? It's a lot more involved than cutting and splicing a few wires... a LOT MORE...

- What is your plan for a throttle body? If you've looked an the Audi intake/throttle body set up, then it should be obvious that there is no room in the Boxster chassis for the stock set-up. At best, you could completely gut the variable geometry intake system and machine an adapter to move the throttle body to the front of the engine... but even there, you will find that there is no room for the stock throttle body in that location either. Which brings me to engine management. What is your plan there? Using the stock Audi system? It's a fairly simple system to retrofit, but as soon as you start talking about mismatching throttle bodies, then you are talking about an aftermarket system, which will be a deal breaker for people who live in states that have strict emissions laws.

I'm not trying to poopoo on your parade, but I've been down this path before and there is no way you can turn this idea into a profitable one unless you can find people who are willing to spend $15K at a minimum for a conversion that doesn't make that much more power than a Porsche 3.2 or 3.4 engine that doesn't require jumping through so many hoops.

Proof that I know what I'm talking about... http://986forum.com/forums/general-discussions/25697-boxster-subaru-conversion-interest.html which also has pictures of the Audi ABZ set up

and... http://986forum.com/forums/general-discussions/37531-subaru-powered-boxster-street-version.html

[mikesz]

Probably VERY difficult to do and not practical, probably defies all rational thought. But really, does anyone know a RATIONAL car guy? A V-8 in a Boxster, this sounds very cool. I remember guys putting Chevy 350's in 914's and there was company in Maine called Kit and Kabootle that sold coversion kits to mount Mazda Rotary engines to Beetle transaxles. I am not affiliated with anybody just another crazy car guy. Keep us posted!

[chromecarz00]

Any updates on this? Really interested and could use it, yesterday.