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Reviving Old thread: 4.5 Stroker love it but want more power
Posted: March 23rd, 2010, 7:43 pm
by daccarettfletez
I can't stand the lack of power so I've decided to tear down the engine and shave the block:
This is my setup:
1993 4.0 block/ obd1
Stock pistons dished to 23 cc
no overbore
no block shaving
4.2 crankshaft and rods
Hi volume oil pump
Stock camshaft
victor reinz head gasket
Ford 24lb injectors
I won't rebuild it again(read no $$$$), just tear down, shave the block, put in a new head gasket, and be done.
Do you think the deck shaving will make a significant difference, I live at sea level, with my current setup I get no pinging...but very little power...
How much should I shave? I was thinking .030-.040, which head gasket?
Re: Reviving Old thread: 4.5 Stroker love it but want more power
Posted: March 24th, 2010, 12:35 pm
by Cheromaniac
daccarettfletez wrote:How much should I shave? I was thinking .030-.040, which head gasket?
Shave 0.030" and get the Victor Reinz 0.043" head gasket. Don't forget to shim the rockers as I mentioned earlier.
Re: 4.5 Stroker I love it but want more power....
Posted: March 24th, 2010, 12:41 pm
by daccarettfletez
yOU think I'll feel the difference? regards
Re: 4.5 Stroker I love it but want more power....
Posted: March 25th, 2010, 11:53 am
by Cheromaniac
Going from an 8.9 CR to a 9.5 CR will net you a 2.5% gain in HP/TQ. You'll hardly feel it but I only suggested it if you also swapped in a Compcams 68-231-4. Otherwise it's not worth it if you keep the stock cam.
Re: 4.5 Stroker I love it but want more power....
Posted: May 4th, 2010, 2:32 pm
by daccarettfletez
Ok getting ready to do online shopping to fix my stroker:
shave .030 of the block
mopar performance headgasket .043
Compcams 68-231-4 cam
Mopar Performance 5249464 valve springs
as suggested by cheromaniac....
Question, and please pardon my ignorance, how many valve springs? 6,12???
can i get away without the roller rockers and pushrods?
Do you think there will be a significant power gain?
Do I also shave the head?
What am I missing or overlooking?
I`ll be retaining same pistons, and bearings....
Re: 4.5 Stroker I love it but want more power....
Posted: May 4th, 2010, 3:13 pm
by amcinstaller
youll need 12. 6 for intake and 6 for exhaust. perhaps look into which locks and retainers youll need with the new springs. i havent paid much attention if the stock ones still work with those springs.
Re: 4.5 Stroker I love it but want more power....
Posted: May 4th, 2010, 3:52 pm
by gradon
I went with the P4452032 chrome-moly retainers and P4529218 keepers with the P5249464 springs. If I ever have to take the head off mine, I'll use the .043" HG.
Re: 4.5 Stroker I love it but want more power....
Posted: May 4th, 2010, 7:03 pm
by daccarettfletez
would stock springs work with the new cam option? Or would the stock keepers and retainers work with the mopar springs? (retainers and springs are worth more than the cam...) howabout the rockers?
Re: 4.5 Stroker I love it but want more power....
Posted: May 5th, 2010, 12:25 pm
by Cheromaniac
daccarettfletez wrote:would stock springs work with the new cam option? Or would the stock keepers and retainers work with the mopar springs? (retainers and springs are worth more than the cam...) howabout the rockers?
It might be a good idea to use the softer stock springs/retainers/keepers for the cam break-in and then swap in the Mopar Performance stuff (you can't mix stock retainers/keepers with Mopar springs).
With stiffer springs it's better to use roller rockers instead of the stock units. Stock pushrods will be fine though chromemoly hardened units are better and pretty cheap anyway.
With the CompCams cam and higher CR, you should gain around 15-20hp.
Re: 4.5 Stroker I love it but want more power....
Posted: May 9th, 2010, 7:49 pm
by daccarettfletez
Ok so I ordered the cam, now a couple more questions:
1. If I shave the block .030 that would give me 0 deck clearance?
2. SCR 9.38 and DCR 8.21, Quench height.043 would this work for me at sealevel with premium gas?
3. What if I just shave .020? I'm kind of concerned for the pinging....
4. The shims you suggest for the rockers, can I buy them, or do I make them?
Sorry for all the questions but I don't want to mess it up again?
Re: 4.5 Stroker I love it but want more power....
Posted: May 11th, 2010, 6:27 am
by Cheromaniac
Cheromaniac wrote:
According to my calculations, the SCR of your engine is only 8.9:1 so that's going to blunt performance a bit but you should be able to run 87 octane fuel.
I suggest you go for a Compcams 68-231-4 cam, upgrade to Mopar Performance 5249464 valve springs with matching retainers/locks, shave 0.030" from the block deck to increase the SCR to 9.5:1 (you'll end up with roughly zero deck clearance and a 0.043" quench), and add 0.030" thick shims under the rocker arm bridges to compensate for the increased lifter preload from the block shave.
While you're there, it wouldn't be a bad idea to replace the pushrods with Crower chromemoly hardened units and swap in a set of Yella Terra YT6627 shaft-mounted roller rockers to add stability to the valvetrain.
The YT roller rockers include a set of shims that you can insert under the rocker arm bridges if required.
You should be able to run 91 octane gas at sea level without pinging. Just make sure the engine runs cool. My cooling system combo is stock 2-row HD radiator, dual electric fans, 180* t'stat, and Flowkooler water pump. The engine's as cool as a cucumber even when it's over 110*F outside.
Re: 4.5 Stroker I love it but want more power....
Posted: May 11th, 2010, 8:27 am
by Don H Jr
With no overbore, I suspect ring sealing problems, thus low power.
Re: 4.5 Stroker I love it but want more power....
Posted: May 11th, 2010, 3:27 pm
by gradon
Before you have the block decked, take your head off, then measure the deck clearance for each piston at TDC(or have your machinist do this). Use the amount from the cylinder with the least clearance to determine what to tell your machinist to deck it.
Re: 4.5 Stroker I love it but want more power....
Posted: May 11th, 2010, 3:44 pm
by daccarettfletez
Thanks! I'll keep that in mind!