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V8 now to rebuild

3K views 23 replies 7 participants last post by  AndyH 
#1 ·
I managed to source a 305 TPI motor locally and am about to embark on the rebuild.
I know many of you think (as i once did) why build a 305 instead of a 350 or 383?
Its a simple matter of what is available here in the UK, what parts are available here and in the US.
Doing the research i found the 305 is capable of an easy 370 to 400hp without force feeding it, although i have a very nice Garrett charger under my bench at the moment im resisting using it on the Astro build.
I couldnt afford to go the LS route either, expensive to buy and more so to build, yes its lighter, yes more HP out of the box...but HOW F****G MUCH????? so thats out of the question

Firstly i needed proper sequential injection which the TPI can give me, it can be modified to run LPG with consummate ease which is very important when you consider our gas prices here.
Secondly i wanted external injectors so i could bin the uber SHITE spider.
Must be older style to mate to my R700 or 4L60E gearbox.

So with the engine bought (very cheap) and only covered 70K miles, she is stripped and off for crack testing and machine work, decking, bearings and line boreing.
I am ordering a set of Trick Flow super 23 175 ally heads from Summit racing, a Comp Cams XM280HR with 0.495/0.502 lift split, a 218/224 duration split and a 112-degree lobe separation angle, usual ARP bolts, Pro Comp roller 1.5 rockers etc.
Im not bothered by Cubic Inches and the search for ultimate power, anything that gives me above 350 usable HP will suit the UK roads well enough, if i go much higher the LPG system will need completely re designing, and i aint gonna do that!!!

I have eventually given up on trying to fix the POS V6 and its constant miss-fire, time to sell it and get some of my money back.

The only thing that isnt 100% clear is if i should stick with the 4L60 or drop in a R700 to dump the electronics.
 
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#3 ·
I think you would better off getting an LT1 full roller cam from a junk yard out of a 90's caprice or buick roadmaster but if you already bought the cam then go with it. If you use a 4l60e you can get a stand alone computer to run it or find out if the engine computer can run it.
 
#4 ·
The motor comes with 2 ECU's however im using a Motec M84. No it wont control the gearbox.
The engine is a roller cam version from a 92 Camaro. After looking at all my choices and doing the extensive research on SuperChevy.com it would seem my choices were pretty spot on as they already built a very similar motor a few years ago.

LT1 was a reverse cooled motor with that god awful distributor arrangement under the front pulley....i hate that design with a pasion, just looks so wrong !!!!

My project is removing the distributor and using LS style coils, 1 per cylinder and true sequential injection for more precise fuelling. Im not going with the MAF sensor either, im going to use the MAP, a CPS and the lower part of the distributor for the CAM sensor.

There are issues with using the GMPP controller (Cost is the main thing @ over $1000 USD) its expensive for what it is. I know there are cheaper ones on the market so ill be looking into those, but with the GB puond to USD rate, the less i buy from the states the better :)
R700 seems a more likely cost effective choice providing it all fits easy enough with few mods, the Motec can supply various speed signals via CAN or hardwire. I need to figure the speed signal out, maybe a speed-healer unit.

Its all falling into place now.
 
#10 ·
UPDATE.

Right so far i have done a fair bit (pics to follow)

The engine is now striped and off for machining, the crank was absolutely immaculate, however its getting a check over and polish at the machine shop.
Block is there and getting a .30 thou re-bore chem clean and decked.

Summit racing now have the following order placed (just waiting for the cam to come in stock before they will ship the whole order)

Trick Flow heads
Crane XM Cam
Crane 1:1.5 solid alloy roller rockers
ARP Head bolt set
Keith Black + 0.30 thou Hypereutectic pistons + rings, no +CC so high compression (11:1) :eek:
New rod and main bearings
Fel Pro TPI manifold gasket set
Fel Pro Engine set bottom end gasket set
Moroso solid fuel pump blank plate
AEM distributor replacement module (you will see why soon) to give cam ref signal
Headman headers
New HC oil pump

Parts already here:

Motec M84 engine ECU with data logger
Motec CDL3 track dash with data logger
Chevrolet 58-2 crank signal trigger kit with new timing chain, sprockets, Modified Vortec timng cover.
Jaguar XJ220 race fuel injectors.
Aeromotive HP HC fuel pump
Aeromotive adjustable fuel pressure regulator
New 3" I/O SS hi flow Cat from the same XJ220 race car spares kit (great when you work for Jaguar design) :banana:
R700 gearbox from the same donor as the engine (1990 Camaro TPI) with less than 30K on it. Im going to rebuild it to 650+ HP spec....so i dont bust the bloody thing when im acting the muppet :dance:
JEGS V8 conversion engine mounts
Wiring kit for the motor.

Yet to order:
LS coil packs x 8
Patriot Side pipe kit.
58mm throttle body kit.

Yep, its not a big cubic inch build, but its still a 400 HP motor (Superchevy built one similar to it without the fuel injection and got 395) so im expecting 400-430 with the modded fuel system and ignition.

As the parts arrive from the machine shop i will start taking pictures during the build.
 
#13 ·
Today was the real start of the build, trying to figure our how to modify the fuel rails on the TPI inlet system.

The problem is that the original fuel lines run from the front of the engine on the F body cars (mine came from a 88 Camaro)
Several problems with the original design are:

Wrong fuel injectors for a high performance build as they are way too small flow rate.
Wrong flow and return connection point
Pressure regulator aint up to the job and is non adjustable.

So i think i have a solution, use an Aeromotive adjustable regulator, fit larger race injectors from a Jaguar XJ220 race car, and re-plumb the manifold using Earls connectors.

Here is some of the work so far:

You can just see on the front rail, i have machined in a blank to block off the original inlet port.

20161112_160818.jpg


This is where im thinking of putting the FPR, as im not using the distributor per-se (im fitting a sensor unit for CPS) so there is a bit more room on the back of the motor.

20161112_160841.jpg
 
#15 ·
A bit of a strange day today (still twiddling the thumbs waiting for my order to be delivered from Summit) another week before it arrives :(

So i thought i would power up the Motec electronics, dash and ECU to start the config files, set parameters for electric water pump, air con, idle control etc etc, and to make sure my laptop can communicate with all the good shizzle :)
I also started work on the dash panel to mount the Motec display.

Here are some pics:

ECU fired up on power supply and talking via CAN :banana:

20161113_174538.jpg


20161113_174622.jpg


Dash now talking to ECU :dance:

20161113_015307.jpg
 
#19 ·
WOW! Christmas came early for you. Must have been a good boy...

-Andrew
 
#21 ·
You said you did a lot of research but I have never heard of anyone successfully using an electric water pump on the street, just a thought, not cutting your project down I just think you may wish to look into that a bit more as I have read it just does not keep up for stop and go traffic. The TPI your using is it factory or aftermarket? Just curious cause the do make a better a better after market one.
 
#23 ·
In 07 BMW started using electric water pumps, lots of models. Toyota Prius uses an electric water pump. I'm sure there are more out there as well. Being able to control the flow regardless of RPM, different mounting options, letting it run after the engine stops, I think you will see more and more as time goes on.
 
#24 ·
Will, you nailed it mate.

An electric pump is PWM controlled which basically means you can control its speed via electronics which match up your engine temp. speed and cooling requirements, keep it running when its switched off allowing it to cool properly and not allowing hot spots to occur deep in the block.
Its way more efficient and allows for less emissions as its not taking HP from the engine to drive it, and it hardly runs at full speed either.

Its win win all round, yep, i agree the early ones were a bit pants, but the new generation of pumps are bloody amazing, also EPAS systems are way better than standard PAS as they are PWM speed controlled too.

Its the 21st century guys :)

(he says, building a V8 for the van) haha
 
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