Replaced Head - Now a couple issues

[IA_Chiefs_fan]

My son's 01 SPI was running fine but we decided to replace the head proactively. I bought him a new, aftermarket head. The install went fine, and it even seems to have a little more power now, but it also "rattles" or "taps" under acceleration now. If I rev it a little bit, while in neutral, it will also backfire; not a loud backfire, maybe even more of a gurgle. Any advice as to what we should look at??

[Sponsor]

[a_2000_se]

Check your timing to be sure the marks didn't move, TDC on compression stroke, after you put the belt on.

Your hydraulic lifters seem firm when you try to push down on each one - not soft or spongy?

It looks like you didn't have your original head reworked but rather got a used reworked head with unknown mileage?

[IA_Chiefs_fan]

Originally Posted by a_2000_se

Check your timing to be sure the marks didn't move, TDC on compression stroke, after you put the belt on.

Your hydraulic lifters seem firm when you try to push down on each one - not soft or spongy?

It looks like you didn't have your original head reworked but rather got a used reworked head with unknown mileage?

Thank you for the response. Timing marks were good afterwards. We will check the lifters. And I bought a brand new, aftermarket head with 0 miles.

[a_2000_se]

Ok - I remember you mentioning going the aftermarket route on another thread. Hopefully this isn't a bad sign of things to come.

But the internals were used parts though?

[IA_Chiefs_fan]

Originally Posted by a_2000_se

Ok - I remember you mentioning going the aftermarket route on another thread. Hopefully this isn't a bad sign of things to come.

But the internals were used parts though?

The entire thing appeared to be brand new. I will add that it idles quiet and smooth. The only time I get noise is when I accelerate.

[Djzx3]

What cam are you using, and what internals are in the head?

[IA_Chiefs_fan]

This is the head I bought. http://www.ebay.com/itm/270789723839...ht_1681wt_1163
They've sold over 30 of these, each with positive feedback.
We're going to check the lifters tomorrow night.
I can hold the car at any RPM level and it is silent. However, I can accelerate and get the noise every time. It doesn't matter if I'm only accelerating from 800 rpms; I still get the noise if I'm feeding it additional gas.

[a_2000_se]

Maybe 'that' head needs a higher octane if nothing else is wrong. A ping or knock when accelerating?

That's a good price for a complete head. I'm skeptical that all the valves/lifters/rockers/springs/clips/cam are new too though.

Have you mailed back your 'old' one yet? If not consider keeping it and finding a complete salvaged/damaged one to mail back - if they take damaged heads.

[IA_Chiefs_fan]

Originally Posted by a_2000_se

Maybe 'that' head needs a higher octane if nothing else is wrong. A ping or knock when accelerating?

That's a good price for a complete head. I'm skeptical that all the valves/lifters/rockers/springs/clips/cam are new too though.

Have you mailed back your 'old' one yet? If not consider keeping it and finding a complete salvaged/damaged one to mail back - if they take damaged heads.

I have not shipped back the old head, and your idea is a good one. They do accept damaged heads. I spoke with the seller today and they agreed it would make sense to try the lifters first. I told them we planned to pull the cover off and check them this week and they offered to send all new lifters so we could just replace them all while I had it apart the next time. I'll keep everyone posted. The seller seemed very concerned and provided good customer service so I'm hopeful this will have a positive outcome. I was fearful they'd just take the money and run. Hopefully it is just a lifter but we will see...

[a_2000_se]

It probably wouldn't hurt to do a compression check on all cylinders before you swap/ disassemble anything. That might tell something. Did you happen to do a compression check on the old original head - maybe compare numbers also.

Plus I'm sure many would be curious what your compression numbers are now too.